UB Study Finds Connection Between Level of Social Interaction and Lower Blood Pressure

BUFFALO, N.Y. -- A study of social interaction and its relationship to blood pressure conducted at the State University of New York at Buffalo shows that people with an extensive social network have lower blood pressure than people with little social contact.

And while connections with others in general were associated with lower blood pressure, certain aspects in particular -- number of siblings for women and household size and club participation in the case of men -- appeared to affect blood pressure more than others.

The study was conducted by researchers in the University at Buffalo's Department of Social and Preventive Medicine, headed by Maurizio Trevisan, M.D., using data from the 1960 Buffalo Blood Pressure Study. Results of the research were published in the November-December issue of Psychosomatic Medicine .

To assess the effect of social interaction on blood pressure, researchers selected five categories of social encounters -- household size, number of siblings, participation in clubs and meetings, religious service attendance and marital status -- and compared them with adjusted mean blood pressure levels for the 656 men and 753 women in the study group.

Among women, the only category that showed a significant relationship to blood pressure was number of siblings. Those with six or more brothers and sisters had significantly lower blood pressure than those having five or less. Among men, significant correlations with blood pressure showed up only with size of household -- the larger the better -- and club participation -- the more active the better.

The authors speculate that the connection between number of siblings and lower blood pressure in women stems from the fact that women generally are more connected to kin throughout their lives than men. "It is possible," they state," that these siblings are a part of these females' daily lives, serving as a buffer in mediating stresses such as child rearing and care of elderly parents."

The finding that individuals, especially men, living in larger households had lower blood pressure suggests to the authors that while crowding in some circumstances creates conflict and stress, increased contact with loved ones is calming.

The researchers were surprised to find no significant relationship between blood pressure and church attendance, since other research has shown an association between attendance at religious services and longer life, less hypertension, and better health, in at least some segments of the populations studied.

The authors raise the possibility that for these people at that point in time, attending church was not a social event.

Susan H. Bland, M.A., doctoral candidate in the Department of Social and Preventive Medicine, is principal author of the study. The coauthors are Vittorio Krogh, M.D., UB research instructor; Warren Winkelstein, M.D., professor and dean of the School of Public Health at the University of California at Berkeley, and Maurizio Trevisan, M.D., associate professor and interim chair of the UB Department of Social and Preventive Medicine.