Twin Studies of Cardiovascular Response to Psychological Challenge: A Review and Suggested Future Directions

Abstract

Abstract This review examines studies which have explored the origins of individual differences in cardiovascular response to psychological challenge by employing the classical twin study methodology. The studies discussed focus on heart rate and/or blood pressure responses. While the widely ranging analytical techniques, relatively small sample sizes, varying health status of subjects, and the use of mainly male samples make more definitive conclusions difficult to draw, the evidence suggests that reactivity to psychological stress is indeed moderately heritable. Further, it appears unlikely that non-genetic influences shared by siblings play any substantial or lasting role in determining individual differences in responsivity. Suggested future directions for research include the incorporation of a wider range of physiological parameters, adoption of some of the new generation of behavioral medicine tasks focusing on psychosocial or social situations, racial and gender group comparisons, and investigation of genetic influences on ambulatory cardiovascular parameters. Finally, the most recent advances in appropriate behavioral genetic analytical approaches are discussed, and path analysis is suggested as the technique of choice for research in this area. By combining the most recent advances in cardiovascular psychophysiology, behavioral medicine, and behavioral genetics, future studies adopting integrative research strategies should further our understanding of genetic influences on cardiovascular reactivity.