Association between social isolation and left ventricular mass

Social isolation is associated with progression of cardiovascular disease, with the most socially isolated patients being at increased risk. Increased left ventricular mass is a predictor of cardiovascular morbidity and mortality. It is not yet clear whether social isolation is a determinant of increased left ventricular mass.

We performed a cross-sectional study of Northern Manhattan Study participants who were free of clinical cardiovascular disease and had obtained transthoracic echocardiograms (n=2021) and a baseline questionnaire on social habits. Social isolation was defined as the lack of friendship networks (knowing fewer than 3 people well enough to visit within their homes). Echocardiographic left ventricular mass was indexed to height(2.7), analyzed as a continuous variable and compared between exposure groups.

The prevalence of social isolation was 13.5%. The average left ventricular mass was significantly higher (50.2 gm/m(2.7)) in those who were, as compared with those who were not (47.6 gm/m(2.7)), socially isolated (P<.05). Higher prevalence of social isolation was found among those less educated, uninsured, or unemployed. There were no significant race-ethnic differences in the prevalence of social isolation. In multivariate analysis, there was a trend toward an association between social isolation and increased left ventricular mass in the total cohort (P=.09). Among Hispanics, social isolation was significantly associated with greater left ventricular mass. Hispanics who were socially isolated averaged 3.9 gm/ht(2.7) higher left ventricular mass compared with those not socially isolated (P=.002). This relationship was not present among non-Hispanic blacks or whites.

In this urban tri-ethnic cohort, social isolation was prevalent and associated with indices of low socioeconomic status. Hispanics who were socially isolated had a greater risk for increased left ventricular mass.