Pre-Exposure Behavioral and Physiological Markers Predict Future Alcohol Consumption Under Free Choice in Rhesus...

The purpose of this study was to assess the utility of various behavioral and physiological parameters from the study in a nonhuman primate model as predictive biomarkers for future alcohol consumption.

The data were derived from 36 male rhesus monkeys (Macaca mulatta) that participated in a chronic oral alcohol self-administration experiment lasting 920 days. Seventeen indicators of spontaneous behavior were registered using the ethogram, and eight physiological parameters were obtained before animal exposure to ethanol. Subsequently, alcohol self-administration under free choice with water was initiated. The median value of ethanol consumption for each monkey was calculated from daily measurements collected over 55 days of unrestricted access to the ethanol solution (4% v/v). Discriminant analysis was performed using behavior and physiological parameters with the highest F coefficients of the canonical discriminant function. Five parameters of the discriminant function (two behavior indicators, total protein, serum cortisol, and body weight) were selected based on the results of several analysis cycles. A discriminant function equation separating two groups of animals was derived. A total of 36 study animals were divided into two groups based on the average value of 0.97 g/kg/day for the individual medians of 55-day ethanol consumption.

In all, 83.3% of the originally grouped observations were correctly classified using a discriminant function derived from behavioral and physiological parameters before ethanol exposure.

A discriminant model was derived that allows delineating future light drinkers from moderate and heavy drinkers with high accuracy before ethanol exposure in a free-choice ethanol consumption model.