Social support and ambulatory blood pressure in older people.

OBJECTIVE: Social support has been associated with greater nocturnal decline (dipping) in blood pressure (BP) in younger and middle-aged individuals. However, it is uncertain if aggregated measures of social support are related to ambulatory SBP in older adults, where high SBP is frequent and clinically challenging.

METHODS: We studied 1047 community-living individuals aged at least 60 years in Spain. Twenty-four-hour ambulatory BP was determined under standardized conditions. Social support was assessed with a seven-item questionnaire on marital status, cohabitation, frequency of contact with relatives, or with friends and neighbors, emotional support, instrumental support, and outdoor companionship. A social support score was built by summing the values of the items that were significantly associated with SBP variables, such that the higher the score, the better the support.

RESULTS: Participants' mean age was 71.7 years (50.8% men). Being married, cohabiting, and being accompanied when out of home were the support items significantly associated with SBP variables. After adjustment for sociodemographic (age, sex, education), behavioral (BMI, alcohol, tobacco, salt consumption, physical activity, Mediterranean diet score), and clinical variables [sleep quality, mental stress, comorbidity, BP medication, and ambulatory BP levels and heart rate (HR)], one additional point in the social support score built with the abovementioned three support variables, was associated with a decrease of 0.93 mmHg in night-time SBP (P = 0.039), totaling 2.8 mmHg decrease for a score of 3 vs. 0. The three-item social support score was also inversely associated with the night/day SBP ratio (β = -0.006, P = 0.010).

CONCLUSION: In older adults, social support is independently associated with lower nocturnal SBP and greater SBP dipping. Further research is needed in prospective studies to confirm these results.