INFLUENCE OF STRESS AND BLOOD-TYPE ON TOXICITY-PREVENTING ACTIVITY AND OTHER CARDIAC RISK-FACTORS

ABO blood type has been shown to be associated with both cardiovascula r risk and toxicity-preventing activity (TxPA) stress response in elde rly males. Twenty middle-aged, healthy males, 14 blood type A and six blood type O, were involved in this project. Volunteers completed a ba ttery of psychological assessments, then gave blood and had several ps ychophysiological measures taken prior to during and after two stresso rs. The stressors consisted of mental arithmetic tasks plus audiotapes of combat sounds and a baby crying. The anger-out and hard-driving sc ores of blood type O subjects were significantly higher than the blood type A means. TxPA decreased significantly as a function of stress an d some suggestive blood type effects of TxPA were found. Plasma protei n, microhematocrit, plasma cortisol, finger temperature, skin conducta nce, blood pressure and two facial electromyograph (EMG) variables wer e also significantly affected by stressors but not by the blood type f actor. No significant differences of any kind were found for total cho lesterol, high-density lipoprotein or pulse variables. The importance of age and other individual subject characteristics was discussed.