Deficits of respiratory-cardiac coupling in heavy drinkers

1. Physiological evidence of chronic alcohol abuse prior to the onset of cl inical signs of alcohol dependence is difficult to obtain. The purpose of t his study was to search for possible non-invasive indicators for chronic al cohol consumption yielding information in addition to conventional biologic al markers. 2. The authors investigated the relationship between respiratory-cardiac co upling and blood alcohol concentration (BAC) in male subjects who lost thei r driver's license from drunk driving. 3. We found that subjects who had a high BAC level (0.16-0.31% at the time of offense) show altered respiratory sinus arrhythmia (RSA) and, in particu lar, an altered heart-rare response to auditory stimulation and compared th em to a control group of social drinkers. Normal subjects showed a pronounc ed acoustic heart-rate response, i.e., particularly during expiration there was a difference between the interbeat-interval (IBI) traces with and with out auditory stimulation. Subjects who had lost their driver's license from drunk driving had an overall severely reduced heart-rate response, that wa s even absent particularly in the subgroup having high BAC values (0.21-0.3 1%). The authors also found some evidence that in the latter subgroup TBI, RSA, and acoustic heart-rate responses partially recover after a six-month period of abstinence. 4. Specific parameters of the acoustic heart-rate response are changed in o ur group of alcohol abusers presumably, due to impairment of vagal function . These parameters may therefore be useful to serve as a non-invasive measu re of alcohol abuse