INFLUENCE OF INCREASED ADRENERGIC ACTIVITY AND MAGNESIUM DEPLETION ONCARDIAC-RHYTHM IN ALCOHOL-WITHDRAWAL

Objective-To investigate the prevalence of arrhythmias in alcoholic me n during disturbances. and its relation to neuroendocrine activation a nd electrolyte disturbances. Design-Consecutive case-control study. Se tting-Primary and secondary care, detoxification ward. Patients and co ntrols-19 otherwise healthy alcoholic men (DSM-III-R) with withdrawal symptoms necessitating detoxification in hospital. 19 age matched, hea lthy non-alcoholic men as controls for Holter recordings. Intervention s-Treatment with chlomethiazole; additional treatment with carbamazepi ne in patients with previous seizures. Main outcome measures-Computer based analyses of mean heart rate and arrhythmias from 24 hour Holter recordings, 24 hour urinary excretion of adrenaline and noradrenaline, magnesium retention measured by means of intravenous loading test, an d serum concentrations of electrolytes. Results-The 24 hour mean heart rate was higher in the alcoholic men (97.4 beats/minute, 95% confiden ce interval (CI) 91.2 to 103.6) than in the controls (69.6 beats/minut e, 95% CI 65.4 to 73.8, P < 0.001). However, there was no difference i n diurnal heart rate variation. The prevalence of premature supraventr icular depolarisations was lower in the alcoholic men (P < 0.05). Neit her atrial fibrillation nor malignant ventricular arrhythmias occurred . The sinus tachycardia in the alcoholic men correlated with the conco mitant urinary excretion of catecholamines (P < 0.05). The mean serum magnesium concentration was 0.78 mmol/l (95% CI 0.73 to 0.83) in the a lcoholic men and 0.83 mmol/l (95% CI 0.81 to 0.85) in a reference popu lation of 55 men aged 40. Magnesium depletion (defined as magnesium re tention > 30%) was detected in 10 alcoholic men (53%). Three alcoholic men had serum potassium concentrations less than or equal to 3.3 mmol /l on admission. Conclusion-increased adrenergic activity, magnesium d epletion, and kalaemia are often seen after drinking, but in alcoholic men without clinical heart disease these changes were not accompanied by arrhythmias other than sinus tachycardia during detoxification in hospital.