The interaction effect of grip strength and lung function (especially FVC) on cardiovascular diseases: a prospective cohort study in Jiangsu Province, China.

OBJECTIVE Lung function and grip strength (GS) are associated with cardiovascular disease (CVD), but whether these risk factors interact to affect CVD is unknown. This study aimed to explore the interactions between lung function and GS with major CVD (defined as fatal/non-fatal myocardial infarction, stroke, and heart failure) incidence. METHODS We conducted a prospective cohort study on the Chinese population in Jiangsu Province. Cox proportional hazards models were used to explore the associations between GS, lung function, and major CVD incidence. RESULTS A total of 5967 participants were included in our study; among them, 182 participants developed major CVD. Participants with low forced vital capacity (FVC) had a higher risk of major CVD (hazard ratio (HR) = 1.45; 95% confidence interval (CI): 1.05-2.01; P < 0.05) compared with normal FVC. The risk of major CVD incidence (HR = 0.54; 95% CI: 0.35-0.83; P < 0.01) was significantly lower in participants with high GS than in individuals with low GS. The interaction between FVC and GS for major CVD incidence (P = 0.006) was statistically significant. Compared with normal FVC participants with high GS, low FVC participants with low GS had the highest risk of major CVD incidence (HR = 2.50; 95% CI: 1.43-4.36; P < 0.01). CONCLUSION Among people with low FVC, the risk of major CVD is lower with high GS. Participants with low FVC and low GS have the highest risk of major CVD. Therefore, more attention should be paid to the incidence of major CVD in individuals with low FVC, especially those who have lower GS.