Muscle grip strength is associated to reduced pulmonary capacity in patients with diabetes

Aim This study investigates the role of muscle strength as a predictive factor for reduced pulmonary function in diabetes. Methods Data from the NHANES 2011–2012 were analyzed. Lung function was assessed with spirometry (FEV1, FVC). Diabetes was assessed with an oral glucose tolerance test (OGTT), glycated hemoglobin (HbA1c), or fasting plasma glucose (FPG). Muscle strength was measured by a grip test using a handgrip dynamometer. Results A total of 3521 people were suitable to be included for analysis in this study. Lung function was reduced in diabetes—after adjustment for covariates, the impact of diabetes on FVC was estimated as −331 mL (SE 48) for known diabetes and −282 mL (SE 41) for undiagnosed diabetes (P < 0.001). Grip strength was also reduced in diabetes. After adjustment for covariates, the impact of diabetes was estimated as −5.9 kg (SE 0.8) for known diabetes (P < 0.001). An association between lung capacity and grip strength in people with known diabetes was observed (R = 0.7, P < 0.001). The adjusted impact on FVC from grip strength was estimated as 13.1 mL (SE 3.4) per kg (P < 0.001). Conclusions Muscle strength appears to be reduced in people with known diabetes, and this seems to affect the respiratory muscles as an independent factor.