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