NFSIJ.MS.ID.555875

Abstract

Introduction: Coffee and its caffeine are commonly central nervous system stimulants and the most frequently known psychoactive substances that have hazardous health problems. Stress is a state of worry or mental tension caused by a difficult situation with a range of emotions, including anxiety and irritability. The research objectives: The study aimed to evaluate the hypothesis that a single cup of coffee consumed daily can result in “Yasser’s cup of coffee stress syndrome (Single cup of coffee stress syndrome)” when exposed to stress.

Methods: Retrospectively and observational, reported 43 case series of patients drinking a single daily coffee with incidental stress exposure were reported. The study was conducted in Kafr El-Bateekh Central Hospital, Fraskour Central Hospital, and a physician outpatient clinic over nearly 5 years and 2 months, starting on August 08, 2019, and ending on October 25, 2024. Naranjo Algorithm-Adverse Drug Reaction was used for the assessment of this syndrome.

Results: A total of 43 patients are included in this study with a slight male sex predominance (51.16%). The mean age of the cases was 37.07 years (range; 14 -70). The most common occupation in the study was housewife; 30.23%. Latent tetany was (83.72%) reported. Wavy triple sign (WTS) was the most frequent ECG sign (62.79%), Wavy double sign (WDS; 11.36%), and combined WTS and WDS (2.33%). Fine tremor (100%), fatigue (58%), palpitations (47%), tachypnea (49%), frontal headaches (42%), dizziness (30%), sense of body tremor with instability (88%), blurred vision (49%), sense of stone in the stomach area 42%), numbness (58%), and non-specific chest pain (16%) were the reported components.

Conclusion: Yasser’s Cup of Coffee Syndrome (Single Cup of Coffee Stress Syndrome) is a newly described syndrome with a constellation of fine tremors, fatigue, palpitations, tachypnea, frontal headaches, dizziness, a sense of body tremor with instability, blurred vision, a sense of stone in the stomach area, numbness, and non-specific chest pain in variant percentages. Clinical tetany and hypocalcemia in ECG were evident. The syndrome happens when patients are incidentally exposed to stress on a single daily cup of coffee. The management of the syndrome was symptomatic and conservative.

Keywords:Coffee; Caffeine; Stimulants; Yasser’s cup of coffee stress syndrome; Single cup of coffee stress syndrome; Syndrome; Cup of coffee

Abbreviations:ADR: Naranjo Algorithm-Adverse Drug Reaction; Ca++: Calcium; CHTW: Camel Hump T-waves; ED: Emergency Department; ECG: Electrocardiography; HR: Heart rate; NSR: Normal Sinus Rhythm; O2: Oxygen; PDE: Phosphodiesterase; POC: Physician Outpatient Clinic; PVCs: Premature Ventricular Complexes; TPS: Tee-Pee sign; WDS: Wavy Double sign; WTS: Wavy Triple sign; BP: Blood pressure; Bru S: Brugada Syndrome; CSAS: Connected Squadron Aircraft sign; DBP: Diastolic Blood Pressure; PVCs: Premature Ventricular Complexes; SA: Sinus Arrhythmia; SBP: Systolic Blood Pressure; RR: Respiratory Rate; ST: Sinus Tachycardia; TPS: Tee-Pee Sign; TWI: T Wave Inversion; UA: Unavailable; WDS: Wavy Double Sign; WTS: Wavy Triple Sign

Introduction

Coffee

Introduction and History: Coffee is one of the three most used beverages in the world after water and tea. Coffea arabica and C. canephora are species of coffee plants that supply the world’s needs. C arabica has a milder but more flavourful and aromatic flavor than C. canephora. C. canephora has double the caffeine content of C. arabica. Wild coffee plants were transported from Kefa in Ethiopia to southern Arabia and cultivated in the 15th century. Kaldi legend, an Arab goatherd who was puzzled by the strange antics of his flock is the base of the discovery of coffee. In 850 CE, Kaldi sampled a berry of evergreen for the feeding goats experiencing a sense of exhilaration. Then he declared his discovery to the world. Coffee drinking was widely spread among Arabs and their neighbors and then into European countries (16th, and 17th, centuries). The coffeehouses flourished across Britain, the British colonies in America, and continental Europe. Yemen and southern Arabia by the end of the 17th century had a pivotal role in Coffee obtaining to the world’s supply, then, to Java, Indonesian archipelago islands, then the Americas (the 18th century), and in the Hawaiian Islands (in 1825) [1].

Decaffeination: Decaffeinated coffee may strike some as an oxymoron. However, several drinkers enjoy with taste of coffee but cannot tolerate the caffeine. In decaffeinated coffee, the caffeine is removed from the green bean before the roasting of coffee. With adulteration of the coffee bean, there is no case of 100 percent caffeine removal. [1].

Caffeine Concentrations in Coffee: Caffeine present amounts in ground coffee ranging between 0.75 and 1.5 percent by weight. Each cup of coffee contains about 100 mg of caffeine. Caffeine is about 42% of coffee-flavored products. The caffeine concentrations are ranging from 3.3 μg/g to 703 μg/g [2]. More than 87% of U.S. adult citizens use regular caffeine consuming about 193 mg caffeine per day with 1.2 mg caffeine/kg BW/day. Coffee (71%), soft drinks (16%), and tea (12%) are known main sources of caffeine [3].

Coffee Chemistry: Caffeine is the main central nervous system stimulant and the most commonly known world psychoactive substance [4]. Caffeine (2-3%), tannin (3-5%), fixed oil (10-15%), and proteins (13%) with traces of carbohydrates are the main constituents of coffee. Caffeine may be present as a salt of Chlorogenic Acid (CGA) [5]. Coffee is considered an antioxidant and a good source of chromium and magnesium that help in controlling blood sugar and insulin. The aliphatic polyamines, putrescine, spermine, and spermidine are present in much in green coffee beans, but all will be decomposed during the roasting. Many lower molecular weight aliphatic compounds may be part of the roasted coffee aroma. There is a mixture of 9-compound in roasted coffee aroma containing isopentane, n-hexane, acetaldehyde, dimethyl sulfide, propanal, isobutanal, isopentanal, methanol, and 2-methylfuran. Despite the aromatic polycyclic hydrocarbons have a tar and soot formation during a firing or roasting process, fluoranthrene and pyrene may be present in green coffee. In coffee there is a series of phenolic compounds such as caffeic and ferulic acids [6].

Caffeine use, hazardous, safety, and withdrawal: Caffeine is the most commonly used drug in the world [7]. Consumption of low to moderate doses of caffeine is usually safe. Several clinical studies reported that some caffeine drinkers will be drug dependent with negative health consequences such as cardiovascular and perinatal complications on continued use [8-10]. Epidemiological research studies reported that coffee consumption may help prevent several chronic diseases such as type 2 diabetes mellitus, Parkinson’s disease, liver cirrhosis, and hepatocellular carcinoma. Despite several prospective cohort studies for coffee users showing no more significant increase in cardiovascular disease risk, it may be associated with hypertension and an increase in plasma homocysteine. There is little evidence to increase the risk of cancer [9].

The research data concluded that for the healthy adult population, moderate daily caffeine intake at a dose level up to 400 mg (-1), or 6 mg kg (-1) BW/day (-1) in a 65-kg person) has no general toxicity, cardiovascular effects, effects on bone status and calcium balance even with consumption of enough calcium, changes in adult behavior, increased incidence of cancer, and effects on male fertility [10]. However, hypertensive patients, children, adolescents, and the elderly are more vulnerable groups to the adverse effects of caffeine on consuming moderate amounts of coffee of daily 3-4 cups containing 300-400 mg/day of caffeine. There is little evidence of health problems vs some evidence of health benefits [9]. Abnormal behaviors were reported with caffeine consumption in a sample of young adults [11]. A study on 36 adolescents who daily consumed caffeine had caffeine dependence with 41.7% tolerance to caffeine, 77.8% withdrawal symptoms after cessation or reduction of caffeine intake, 38.9% desire or unsuccessful attempts to control use, and 16.7% endorsed use despite educational knowledge of caffeine problems [12]. Addiction and dependency on caffeine were reported in some studies for caffeine users [11]. Many caffeine users are unable to reduce consumption despite educational knowledge of caffeine problems. 80% had reported prior serious attempts to modify caffeine use, and 43% were advised to reduce or eliminate caffeine. 93% met the criteria have caffeine dependence based on DSM-IV-TR substance dependence criteria. 96% had endorsed criteria for withdrawal, 89% had persistent desire or failed attempts to control use, and 87% used despite educational knowledge of caffeine problems. 59% had reasons for wanting to modify caffeine use due to health-related and 35% did not want to be dependent on caffeine [13].

Caffeine and Neuropharmacology: Caffeine is an antagonist at adenosine receptors that block endogenous adenosine [14,15] resulting in a range of effects opposite those of adenosine with behavioral stimulant effects associated with the drug [16]. However, caffeine stimulates dopaminergic activity by removing the negative modulatory effects of adenosine at dopamine receptors. There is a debate about the predominant psychstimulant effects on different adenosine receptor subtypes and the role of pre- versus post-synaptic mechanisms of the effects of caffeine on the adenosine receptor antagonist [17]. Several negative and serious health problems such as anxiety, insomnia, hypertension, Myocardial Infarction (MI), bladder instability, Gastro-Esophageal Reflux (GERD), spontaneous abortion, and fetal growth retardation may happen with caffeine consumption [8].

Caffeine and clinical features: Caffeine generally has dosedependent effects with positive or desirable effects at lower doses (i.e., ≤ 400 mg) and undesirable effects at higher doses [18,19]. The following signs were noted at doses of 250 mg increased arousal, alertness, concentration, and well-being [18,20] but increasing tension, nervousness, anxiety, excitement, irritability, nausea, paresthesia, tremor, perspiration, palpitations, restlessness and possibly dizziness were noted at dose of 500 mg [20]. Unfortunately, chills, flushing, nausea, headache, palpitations, and tremors were noted at high sub-lethal doses (7-10 mg/kg) [18].

Paradoxical and toxic caffeine effects: Sometimes, paradoxical effects of caffeine were reported such as hypertensionhypotension and tachycardia-bradycardia. This may be due to divergent molecular targets based on the concentrations or divergent physiological responses to different exposure levels. So, hypertension may be induced by high catecholamine levels via presynaptic adenosine A1 antagonism, blockage of the adenosine A1 receptors of the adrenal medulla, and inhibition of the vasodilation effects of adenosine via adenosine A2 antagonism in cases of therapeutic serum caffeine [15, 21-25]. Conversely, hypotension may result in Phosphodiesterase (PDE) inhibition in cases of toxic or overdose concentrations [3]. While hypertension is usually due to increased catecholamine release via adenosine antagonism and direct vasoconstrictive response due to adenosine antagonism after intake of therapeutic amounts, it is interesting that hypotension is frequently noted in cases of severe overdose, mostly due to PDE inhibition [15,21,22,26-28]. Hypertension, hypotension, bradycardia, AV block, supraventricular tachycardia, ventricular tachycardia or ventricular fibrillation, myocardial ischemia, myocardial infarction, and cardiac arrest, nausea, vomiting, severe recurrent vomiting, abdominal pain, diarrhea, delusions, hallucinations anxiety, agitation, excitation, seizures, headache, cerebral edema, coma, hypokalemia, hyponatremia, hypocalcemia, metabolic acidosis, respiratory alkalosis, hyperglycemia, fever, weakness, rigidity, tremor, rhabdomyolysis, hyperventilation, respiratory failure, tinnitus, dizziness, diuresis, and death are reported features in caffeine intoxication [29- 36]. Hypertensive effects of caffeine diminish with chronic consumption [37-39]. Hypotension is commonly due to tachydysrhythmias due to caffeine subsequently causing low cardiac output, and increased catecholamine levels agonizing B2 receptors, via PDE inhibition, resulting in vasodilation [26,40- 42]. Hypokalemia is often noted in cases of overdose due to activation of the Na+/K + pump or Na+/K+ -ATPase. In cases of overdose, Caffeine-induced hypokalemia is due to B2 agonism from catecholamine release due to either adenosine antagonism or PDE inhibition [41-45]. Low or moderate doses of caffeine which don’t cause increases in plasma catecholamine levels still have low serum potassium [46,47].

Course and Management: Supportive care is the main line for the treatment of caffeine intoxication. Decontamination and increased elimination may be effective [33]. The approach for management is depending on the patient’s symptoms, physical status, and ingestion circumstances [8]. However, caffeine use disorder appears to be a chronic relapsing condition [8,13]. Some caffeine users adequately have a hard need to quit or reduce caffeine doses. Juliano and colleagues [13] reported that 47% of 258 caffeine users seeking treatment in the form of one-onone counseling, 12% were in the form of group counseling, 25% were in the form of a self-help booklet, and 4% were in the form of phone-based assistance [8]. Hypertensive effects of caffeine may be diminished with chronic consumption [37,38,29]. If there are tachydysrhythmias with a decreased cardiac output causing hypotension, a B1 antagonist will be effective [48]. Selective B1 blockers such as esmolol and metoprolol would not be expected to yield beneficial effects if it is due to B2 agonism [48,49]. Isotonic intravenous fluid is the drug of choice for hypotension. Vasopressors such as phenylephrine or epinephrine alternatively may be used. Unfortunately, beta antagonists such as esmolol or propranolol also have refractory hypotension [49].

Method of study and patients

My study was case series, observational, and retrospective for 43 cases. The study was conducted in the Physician Outpatient Clinic (POC), Kafr El-Bateekh Central Hospital, and Fraskour Central Hospital. The author reported 43 patients drinking a single daily cup of coffee over nearly 5 years and 2 months, starting on August 08, 2019, and, ending on October 25, 2024 (Table 1). A complete clinical and specifically neurological examination was done for all cases. CBC, liver enzymes, RBS, cardiac biomarkers, and renal function tests were done in selected cases. ECG tracing was provided for all cases. Ionized calcium was used in some cases. Clinical and laboratory data of all cases were collected (Tables 2 & 3).
• Suggesting hypothesis and research objectives: Suggesting hypothesis: Patients on a drink single daily cup of coffee can experience Yasser’s cup of coffee stress syndrome (Single cup of coffee stress syndrome) on exposure to stress. The research objectives to evaluate this hypothesis might include: What is Yasser’s cup of coffee stress syndrome (Single cup of coffee stress syndrome)? What is stress? How can a drink single daily cup of coffee result in Yasser’s cup of coffee stress syndrome (Single cup of coffee stress syndrome) on exposure to stress? Is the study supported by past publicized literature studies? Is there a relationship between syndrome and stress? What is the magnitude of Yasser’s cup of coffee stress syndrome (Single cup of coffee stress syndrome)?
• Assessment of treatment response was done with the presence of Naranjo Algorithm-Adverse Drug Reaction (ADR) was used for the assessment of the symptoms and signs of the syndrome in all cases in the current study (Tables 4 and 5). All the above criteria were also assessed in parallel to the clinical status. The patient’s informed consent was not taken. Ethical issues were considered. However, there was no approval due to the study was a retrospective, observational, case series.

Separation was achieved on a Gemini C18 column (4.6 × 100 mm, 3 μm, Phenomenex. Inc., Torrance, CA, USA) using a linear gradient elution program with a mobile phase containing solvent A (0.4%, v/v, formic acid in distilled deionized water) and solvent B (acetonitrile). Initially it started with a gradient of 18% B, changing to 32% in 15 min and finally to 50% in 40 min followed by washing for 25 min with a flow rate of 1.0 mL/ min. Sample injection volume was 10 μL and the resulting peaks were monitored at 280 nm. Identification of caffeic acid, caffeine and other compounds were achieved by comparing the retention time and absorption spectra of peaks to the external standard compounds.

Eligibility criteria

Inclusion criteria: All patients drinking a single daily cup of coffee. Exclusion criteria 1. Evidence of patients drinking several daily cups of coffee. 2. Patients drinking of decaffeinated coffee. 3. Patients drinking caffeinated soft drinks.

Case presentations

Case No. 1: A 20-year-old single male furniture painter an Egyptian patient was presented to the Emergency Department (ED) with palpitations. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, a sense of body tremor with instability, frontal headaches, blurred vision, and a sense of stone in the stomach area were associated symptoms. Naranjo Algorithm-Adverse Drug Reaction (ADR) Probability Scale was 9. He was tested for latent tetany which was positive. ECG tracing shows sinus tachycardia and a wavy triple sign of hypocalcemia (Figure 1). The patient was managed conservatively with a complete clinical recovery had happened. An oral calciumvitamin D tab was prescribed for two weeks.

Case No. 2: A 33-year-old married housewife female Egyptian patient was presented to the POC with psychogenic hyperventilation syndrome and palpitations. This happened after psychological stress with a single daily coffee drink. Fine tremors, fatigue, numbness, dizziness, a sense of body tremor with instability, frontal headaches, and a sense of stone in the stomach area were associated symptoms. There is a recent history of swallowing caffeinated paracetamol tablets. Naranjo Algorithm-ADR Probability Scale was 8. She was tested for latent tetany which was positive. ECG tracing shows sinus tachycardia, non-specific ST-segment depression, and a wavy triple sign of hypocalcemia (Figure 2). The patient was managed conservatively with a complete clinical recovery had happened. An oral calciumvitamin D tab was prescribed for two weeks.

Case No. 3: A 39-year-old divorced housewife female Egyptian patient was presented to the POC with tachypnea, numbness, and palpitations. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, a sense of body tremor with instability, fatigue, and dizziness were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. She was tested for latent tetany which was positive. ECG tracing shows Normal Sinus Rhythm (NSR), non-specific ST-segment depression, Tee-Pee sign, Camel hump T-waves, and a wavy triple sign of hypocalcemia (Figure 3). The patient was managed conservatively with a complete clinical recovery had happened. An oral calciumvitamin D tab was prescribed for two weeks.

Case No. 4: 50-year-old married male teacher an Egyptian patient was presented to the POC with tachypnea, fatigue, dizziness, and palpitations. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, numbness, sense of body tremor with instability, blurred vision, and frontal headaches were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. He was tested for latent tetany which was negative. ECG tracing shows NSR, Connected Squadron Aircraft sign, and prolonged PR interval (Figure 4). The patient was managed conservatively with a complete clinical recovery had happened.

Case No. 5: A 14-year-old adolescent male student Egyptian patient was presented to the POC with psychogenic hyperventilation syndrome, tetany, paresthesia, numbness, and palpitations. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, a sense of body tremor with instability, fatigue, and dizziness were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. ECG tracing shows NSR, Wavy triple sign, single beat and non-specific T-wave inversion (Figure 5). The patient was managed initially with IVB of calcium gluconate then conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 6: A 45-year-old married male carpenter Egyptian patient was presented to the ED with palpitations and pleurisy. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, a sense of body tremor with instability, blurred vision, and a sense of stone in the stomach area were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. He was tested for latent tetany which was positive. ECG tracing shows NSR, Brugada syndrome, and Wavy double sign (Figure 6). The patient was managed conservatively with a complete clinical recovery had happened.

Case No. 7: A 64-year-old married housewife female Egyptian patient was presented to the POC with palpitations. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, a sense of body tremor with instability, and a sense of stone in the stomach area were associated symptoms. There is a recent history of swallowing of caffeinated paracetamol tablets. Naranjo Algorithm-ADR Probability Scale was 8. She was tested for latent tetany which was positive. ECG tracing shows sinus tachycardia, non-specific ST-segment depression, and a wavy triple sign of hypocalcemia (Figure 7). The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 8: A 45-year-old married housewife female Egyptian patient was presented to the POC with palpitations, tetany, numbness, and tachypnea. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, fatigue, dizziness, a sense of body tremor with instability, blurred vision, frontal headaches, and a sense of stone in the stomach area were associated symptoms. There is a recent history of swallowing of caffeinated paracetamol tablets. Naranjo Algorithm-ADR Probability Scale was 8. ECG tracing shows sinus tachycardia, a wavy triple sign of hypocalcemia, and a wavy double sign of hypocalcemia (Figures 7-8). The patient was managed initially with IVB of calcium gluconate then conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 9: A 16-year-old adolescent female student Egyptian patient was presented to the POC with psychogenic hyperventilation syndrome, non-specific chest pain, paresthesia, numbness, and palpitations. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, frontal headaches, fatigue, dizziness, and a sense of body tremor with instability were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. She was tested for latent tetany which was positive. ECG tracing shows NSR and frequent multimorphic Premature Ventricular Complexes (PVCs) (Figure 9). The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 10: A 26-year-old married male officer an Egyptian patient was presented to the ED with palpitations and tachypnea. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, a sense of body tremor with instability, frontal headaches, fatigue, and dizziness were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. He was tested for latent tetany which was positive. ECG tracing shows sinus tachycardia and a wavy triple sign of hypocalcemia (Figure 10). The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 11: A 29-year-old married female housewife Egyptian patient was presented to the POC with numbness. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, a sense of body tremor with instability, and fatigue were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. She was tested for latent tetany which was positive. ECG tracing shows NSR and a wavy triple sign of hypocalcemia. The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 12: A 67-year-old married male farmer, Egyptian patient was presented to the POC with numbness and dizziness. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors with instability, and a sense of stone in the stomach area were associated symptoms. He was tested for latent tetany which was positive. Naranjo Algorithm-ADR Probability Scale was 9. ECG tracing shows NSR and a wavy double sign of hypocalcemia. The patient was managed conservatively with a complete clinical recovery had happened. An oral calciumvitamin D tab was prescribed for two weeks.

Case No. 13: A 28-year-old married farmer male, Egyptian patient was presented to the POC with non-specific chest pain and tachypnea. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, a sense of body tremor with instability, and blurred vision were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. He was tested for latent tetany which was positive. ECG tracing shows NSR. The patient was managed conservatively with a complete clinical recovery had happened.

Case No. 14: A 29-year-old married male teacher, Egyptian patient was presented to the POC with numbness and dizziness. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, a sense of body tremor with instability, fatigue, and blurred vision were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. He was tested for latent tetany which was positive. ECG tracing shows sinus arrhythmia and a wavy double sign of hypocalcemia. The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 15: 30-year-old married male worker, Egyptian patient was presented to the POC with dizziness. This happened after psychological stress with a single daily coffee drink. Fine tremors, a sense of body tremor with instability, frontal headaches, and a sense of stone in the stomach area were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. He was tested for latent tetany which was positive. ECG tracing shows NSR. The patient was managed conservatively with a complete clinical recovery had happened.

Case No. 16: An 18-year-old single student female, Egyptian patient was presented to the POC with non-specific chest pain, and tachypnea. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, a sense of body tremor with instability, numbness, frontal headaches, blurred vision, and a sense of stone in the stomach area were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. She was tested for latent tetany which was positive. ECG tracing shows NSR, a wavy triple sign of hypocalcemia, and S1S2S3 syndrome. The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 17: A 30-year-old married female Blacksmith, Egyptian patient was presented to the POC with dizziness and numbness. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, a sense of body tremor with instability, fatigue, and blurred vision were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. She was tested for latent tetany which was positive. ECG tracing shows NSR and a wavy triple sign of hypocalcemia. The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 18: A 45-year-old married female housewife, Egyptian patient was presented to the POC with tachypnea. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, a sense of body tremor with instability, and numbness were associated symptoms. Naranjo Algorithm- ADR Probability Scale was 9. She was tested for latent tetany which was positive. ECG tracing shows NSR and a wavy double sign of hypocalcemia. The patient was managed conservatively with a complete clinical recovery had happened. An oral calciumvitamin D tab was prescribed for two weeks.

Case No. 19: A 55-year-old married male officer, Egyptian patient was presented to the ED with dizziness and numbness. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, a sense of body tremor with instability, and fatigue were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. He was tested for latent tetany which was positive. ECG tracing shows NSR. The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 20: A 33-year-old married female teacher, Egyptian patient was presented to the POC with tetany, non-specific chest pain, and tachypnea. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, numbness, a sense of body tremor with instability, fatigue, and dizziness were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. ECG tracing shows NSR and a wavy triple sign of hypocalcemia. The patient was managed initially with IVB of calcium gluconate then conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 21: A 44-year-old married male farmer Egyptian patient presented to the POC with dizziness and numbness. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, a sense of body tremor with instability, frontal headaches, and a sense of stone in the stomach area were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. He was tested for latent tetany which was positive. ECG tracing shows NSR and a wavy triple sign of hypocalcemia. The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 22: A 59-year-old married male worker Egyptian patient was presented to the POC with numbness. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, a sense of body tremor with instability, blurred vision, and frontal headaches were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. He was tested for latent tetany which was positive. ECG tracing shows NSR and a wavy triple sign of hypocalcemia. The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 23: A 36-year-old married male officer Egyptian patient was presented to the POC with tetany and tachypnea. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, fatigue, dizziness, numbness, a sense of body tremor with instability, and blurred vision were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. ECG tracing shows NSR and a wavy triple sign of hypocalcemia. The patient was managed initially with IVB of calcium gluconate then conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 24: A 31-year-old married female Doctor, Egyptian patient was presented to the POC with numbness and non-specific chest pain. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, a sense of body tremor with instability, frontal headaches, and blurred vision were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. He was tested for latent tetany which was positive. ECG tracing shows NSR and a wavy triple sign of hypocalcemia. The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 25: An 18-year-old adolescent male student Egyptian patient was presented to the POC with psychogenic hyperventilation syndrome, tetany, paresthesia, numbness, and palpitations. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, a sense of body tremor with instability, fatigue, dizziness, numbness, and a sense of stone in the stomach area were associated symptoms. Naranjo Algorithm- ADR Probability Scale was 9. ECG tracing shows sinus tachycardia and a wavy triple sign of hypocalcemia. The patient was managed initially with IVB of calcium gluconate then conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 26: A 50-year-old married male farmer Egyptian patient presented to the POC with fatigue, numbness, and palpitations. This happened after psychological stress with a single cup of coffee drink. Fine tremors, frontal headaches, and a sense of body tremor with instability were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. He was tested for latent tetany which was positive. ECG tracing shows sinus tachycardia, a wavy triple sign of hypocalcemia, and a wavy double sign of hypocalcemia. The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 27: A 70-year-old married male farmer Egyptian patient was presented to the POC with fatigue. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors with instability, and a sense of stone in the stomach area. Naranjo Algorithm-ADR Probability Scale was 9. He was tested for latent tetany which was positive. ECG tracing shows NSR and a wavy double sign of hypocalcemia. The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 28: A 37-year-old married male officer Egyptian patient was presented to the POC with palpitations, non-specific chest pain, and tachypnea. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, dizziness, sense of body tremor with instability, blurred vision, and numbness were associated symptoms. Naranjo Algorithm- ADR Probability Scale was 9. He was tested for latent tetany which was positive. ECG tracing shows sinus tachycardia, a wavy triple sign of hypocalcemia, and PVCs. The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 29: A 48-year-old married male carpenter Egyptian patient presented to the ED with palpitations and tachypnea. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, numbness, a sense of body tremor with instability, and blurred vision were associated symptoms. He was tested for latent tetany which was positive. . Naranjo Algorithm- ADR Probability Scale was 9. ECG tracing shows sinus tachycardia. The patient was managed conservatively with a complete clinical recovery had happened.

Case No. 30: A 28-year-old married female housewife Egyptian patient was presented to the POC with tachypnea. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, frontal headaches, a sense of body tremor with instability, fatigue, dizziness, blurred vision, and numbness were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. She was tested for latent tetany which was positive. ECG tracing shows NSR and a wavy triple sign of hypocalcemia. The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 31: A 23-year-old single female student Egyptian polio patient was presented to the POC with palpitations. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, a sense of body tremor with instability, fatigue, and a sense of stone in the stomach area were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. She was tested for latent tetany which was positive. ECG tracing shows sinus tachycardia. The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 32: A 35-year-old married male farmer Egyptian patient presented to the POC with numbness and tachypnea. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, numbness, and blurred vision were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. He was tested for latent tetany which was negative. ECG tracing shows NSR, a wavy triple sign of hypocalcemia, and an Incomplete Right Bundle Branch Block (IRBBB). The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 33: A 45-year-old married male farmer Egyptian patient presented to the POC with numbness and non-specific chest pain. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, frontal headaches, fatigue, dizziness, and blurred vision were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. He was tested for latent tetany which was positive. ECG tracing shows NSR and a wavy triple sign of hypocalcemia. The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 34: A 40-year-old married female housewife Egyptian patient was presented to the POC with numbness, tetany, and hyperventilation syndrome. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, a sense of body tremor with instability, fatigue, and a sense of stone in the stomach area were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. ECG tracing shows NSR and PVCs. The patient was managed initially with IVB of calcium gluconate then conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 35: A 33-year-old married female housewife Egyptian patient presented to the POC with palpitations and tachypnea. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, numbness, a sense of body tremor with instability, and blurred vision were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. She was tested for latent tetany which was positive. NSR and a wavy triple sign of hypocalcemia. The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 36: A 22-year-old married female housewife Egyptian patient was presented to the POC with tachypnea. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, fatigue, frontal headaches, a sense of body tremor with instability, and a sense of stone in the stomach area. Naranjo Algorithm-ADR Probability Scale was 9. She was tested for latent tetany which was positive. ECG tracing shows NSR and a wavy triple sign of hypocalcemia. The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 37: A 17-year-old single female student Egyptian patient was presented to the POC with fatigue. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, frontal headaches, blurred vision, and a sense of stone in the stomach area were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. She was tested for latent tetany which was negative. ECG tracing shows NSR. The patient was managed conservatively with a complete clinical recovery had happened.

Case No. 38: A 31-year-old married housewife female Egyptian patient was presented to the ED with tachypnea. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, numbness, a sense of body tremor with instability, and blurred vision were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. She was tested for latent tetany which was positive. ECG tracing shows NSR and a wavy triple sign of hypocalcemia. The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 39: A 17-year-old married female student Egyptian patient presented to the POC with numbness, musculoskeletal chest pain, palpitations, and hyperventilation. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, a sense of body tremor with instability, blurred vision, fatigue, and dizziness were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. She was tested for latent tetany which was positive. ECG tracing shows sinus arrhythmia and a wavy triple sign of hypocalcemia. The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 40: A 29-year-old married housewife female Egyptian patient presented to the POC with palpitations, numbness, and tachypnea. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, fatigue, dizziness, a sense of body tremor with instability, and blurred vision were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. She was tested for latent tetany which was positive. ECG tracing shows NSR and a wavy triple sign of hypocalcemia. The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 41: A 60-year-old married housewife female Egyptian patient presented to the POC with numbness and fatigue. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, frontal headaches, fatigue, blurred vision, and a sense of stone in the stomach area were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. She was tested for latent tetany which was positive. ECG tracing shows NSR and a wavy triple sign of hypocalcemia. The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 42: A 46-year-old married male carpenter Egyptian patient presented to the ED with palpitations and numbness. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, frontal headaches, and a sense of body tremor with instability were associated symptoms. Naranjo Algorithm-ADR Probability Scale was 9. He was tested for latent tetany which was positive. ECG tracing shows sinus tachycardia and a wavy triple sign of hypocalcemia. The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Case No. 43: A 33-year-old married male officer Egyptian patient was presented to the ED with dizziness and tachypnea. This happened after psychological stress with a single daily cup of coffee drink. Fine tremors, frontal headaches, a sense of body tremor with instability, numbness, fatigue, and a sense of stone in the stomach area were associated symptoms. Naranjo Algorithm- ADR Probability Scale was 9. He was tested for latent tetany which was positive. ECG tracing shows NSR and a wavy triple sign of hypocalcemia. The patient was managed conservatively with a complete clinical recovery had happened. An oral calcium-vitamin D tab was prescribed for two weeks.

Results

A total of 43 patients are included in this study. There is slight male sex predominance; 51.16% (n: 22) vs. 48.84% (n = 21) of the male patients. The mean age of the cases was 37.07 years (range; 14-70).

The most common occupation in the study was housewife was 30.23% (n = 21). Latent tetany was (83.72% n = 36), and manifested was (13.95% n = 6). Wavy triple sign (WTS) was the most frequent ECG sign (62.79% n = 27), Wavy double sign (WDS (11.36%; n = 5), combined WTS and WDS (2.33%; n = 1), normal (2.33%; n = 1), and others were (20.93%; n = 9). Fine tremor (100%; n = 43), fatigue (58%; n = 25), palpitations (47%; n = 20), tachypnea (49%; n = 21), frontal headaches (42%; n = 18), dizziness (30%; n = 13), sense of body tremor with instability (88%; n = 88), blurred vision (49%; n = 21), sense of stone in the stomach area (42%; n = 18), numbness (58%; n = 25), non-specific chest pain (16%; n = 6) clinical evidence of latent tetany: 83.7% (n = 36), clinical evidence of manifested tetany: 14% (n = 6), and ECG evidence of hypocalcemia: 81% (n = 35)were the reported components. The results of the study are summarized in (Figure 1, Tables 1-2). Naranjo Algorithm-Adverse Drug Reaction (ADR) in the current study was used for assessment of the symptoms and signs of the syndrome in all cases (Tables 4-5). Naranjo Algorithm- Adverse Drug Reaction (ADR) Probability Scale all cases except cases No. 2, 7, and 8. Naranjo’s probability scale in the current case study was +8 to +9. This means that there was a probable relationship between these adverse reactions and coffee drinking (Tables 4-5).

Age; Range: 14-70, Minimal; 14, maximal; 70, mean; 37.07, median: 33, and mode: 33 (Table 2). Sex; Male sex; 51.16% (22 cases) and female sex; 48.84% (21 cases) (Figure 11A). Occupation: Housewife; 30.23% (13 cases), farmer; 16.28% (7 cases), student; 16.28% (7 cases), worker; 4.65% (2 cases), teacher; 6.98% (3 cases), carpenter; 6.98% (3 cases), officer; 11.63% (5 cases), painter; 2.33% (1 case), blacksmith; 2.33% (1 case), and doctor; 2.33% (1 case) (Table 2) (Figure 11B). Clinical tetany: Latent; 83.72% (36 cases), manifested; 13.95% (6 cases), and negative; 2.33% (1 case) (Table 2) (Figure 11C). Signs of Hypocalcemia in ECG: WTS; 62.79% (27 cases), WDS; 11.36% (5 cases), WTS+WDS; 2.33% (1 case), normal; 2.33% (1 case), and others; 20.93% (9 cases) (Table 2) (Figure 11D). Components of syndrome: Fine tremor: 100% (43 cases), fatigue: 58% (25 cases), palpitations: 47% (20 cases), tachypnea: 49% (21 cases), frontal headaches: 42% (18 cases), dizziness: 30% (13 cases), sense of body tremor with instability: 88% (38 cases), blurred vision: 49% (21 cases), sense of stone in the stomach area: 42% (18 cases), numbness: 58% (25 cases), non-specific chest pain: 16% (6 cases), clinical evidence of latent tetany: 83.7% (36 cases), clinical evidence of manifested tetany: 13.95% (6 cases), and ECG evidence of hypocalcemia: 81% (35 cases) (Table 3) (Figure 11E).

Discussion

Past studies: There are no past literature publications, regarding the Yasser’s Cup of Coffee Syndrome (Single Cup of Coffee Stress Syndrome).

Assessment of the symptoms and signs of the syndrome: Naranjo Algorithm-Adverse Drug Reaction (ADR) was used in the current study for assessment of the symptoms and signs of the syndrome in all cases (Tables 4-5). Naranjo Algorithm-ADR Probability Scale for all cases except cases No. 2, 7, and 8 (93%) was 9 and the Scale for remaining cases (No. 2, 7, and 8) (7%) was 8. So, Naranjo’s algorithm-ADR probability scale in the current study was +8 to +9. A scale of 9 means a definite relationship between these adverse effects and single daily coffee drinking. But a scale of 8 means a probable relationship between these adverse effects and single daily coffee drinking [50]. This means that there was a probable relationship between these adverse effects and single daily coffee drinking (Tables 4-5).

The description of Yasser’s Cup of Coffee Stress Syndrome (Single Cup of Coffee Stress Syndrome): Yasser’s Cup of Coffee Stress Syndrome (Single Cup of Coffee Stress Syndrome) is a newly described syndrome with a constellation of fine tremors, fatigue, palpitations, tachypnea, frontal headaches, dizziness, a sense of body tremor with instability, blurred vision, a sense of stone in the stomach area, numbness, and non-specific chest pain in variant percentages. Clinical tetany and electrocardiographic evidence of hypocalcemia are common associated findings. Both constellations of the syndrome, symptoms, signs, clinical tetany, and electrocardiographic evidence of hypocalcemia represent the syndrome’s components. These components of the syndrome commonly happen for the drink persons who are exposed to emotional stress after a single daily cup of coffee (Figure 12).

Stress: Stress was a main risk factor in eliciting the symptoms and signs of Yasser’s Cup of Coffee Syndrome (Single Cup of Coffee Stress Syndrome). The stress was emotional or psychogenic. Stress is a state of worry or mental tension caused by a difficult situation with a range of emotions, including anxiety and irritability. Stressful situations can cause or exacerbate mental health conditions, especially, anxiety which needs access to health care. Everyone reacts differently to these stressful situations. The associated symptoms of stress surely vary from one to one. Chronic stress may worsen pre-existing health conditions. Patients may present with headaches, body pains, an upset stomach, or trouble sleeping [51].

Management: The management of Yasser’s Cup of Coffee Syndrome (Single Cup of Coffee Stress Syndrome) was symptomatic and conservative. The management varies according to the clinical status, severity of symptoms, and associated risk factors. Reassurance and calming the patients is the main therapy. IV fluids, tonics, calcium injections, and antihistamines are sometimes used.

Differential diagnosis: Panic attacks are the main differential diagnosis for Yasser’s Cup of Coffee Syndrome (Single Cup of Coffee Stress Syndrome). History and clinical status help in exclusion.

Limitations of the study: There were no known study limitations.

Conclusion and recommendations

Yasser’s Cup of Coffee Syndrome (Single Cup of Coffee Stress Syndrome) is a newly described syndrome with a constellation of fine tremors, fatigue, palpitations, tachypnea, frontal headaches, dizziness, a sense of body tremor with instability, blurred vision, a sense of stone in the stomach area, numbness, and non-specific chest pain in variant percentages. Clinical tetany and hypocalcemia in ECG were evident. The syndrome happens when patients are incidentally exposed to stress on a single daily cup of coffee. The management of the syndrome was symptomatic and conservative. Further widening the research is essential.

Conflicts of interest

There are no conflicts of interest.

Acknowledgment

I wish to thank the team nurses of the critical care unit in Kafr El-Bateekh Central Hospital who made extra-ECG copies to help me. I want to thank my wife for saving time and improving the conditions to support me.

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