Effects of alcohol use and gender on the dynamics of EKG time-series data

Hurst analysis of EKG data obtained from a population of alcoholic (n = 13) and nonalcoholic (n = 48) subjects was undertaken. Potential subjects (n = 120) were screened using the Schedule for Affective Disorders and Schizoph renia and Structured Clinical Interview for DSM-III instruments. Data from subjects with a diagnosis of current alcohol dependence were analyzed. Subj ects with diagnoses such as major depression, bipolar disorder or schizophr enia (Axis I diagnoses), or personality disorders (Axis II diagnoses) were excluded from analysis. Subjects undergoing testing were free of alcohol an d illicit drugs. Alcoholic subjects had no clinical evidence of alcohol wit hdrawal symptoms at the time of testing. EKG data were obtained with eyes o pen or with eyes closed. Approximately 3.5 min of data were obtained for ea ch condition. Alcoholic subjects had less complex heart rate dynamics as ev idenced by higher values of H = 0.18 +/- 0.05 (mean +/- SEM), compared with healthy comparison subjects with H = 0.09 +/- 0.02, p < 0.014 for the eyes closed condition, and H = 0.17 +/- 0.05 (mean +/- SEM) compared with healt hy comparison subjects with H = 0.07 +/- 0.02, p < 0.011 for the eyes open condition. A gender effect was seen, with female subjects showing evidence of more complex heart rate dynamics than male subjects.