Pulmonary functions in patients with subclinical hypothyroidism

Objective: To determine whether alterations in pulmonary function takes place in subclinical hypothyroidism by examining the diffusion lung capacity and muscle strength of such patients. Methods: This is a descriptive study conducted in 2009 at Haseki Training and Research Hospital, Istanbul, Turkey. Hundred and twenty-six patients with subclinical hypothyroidism and 58 age and sex matched individuals were recruited. Simple spirometry tests were performed, and pulmonary diffusion capacity (DLco) and muscle strength were measured. Results: ScH patients showed a significant reduciton of the following pulmonary function tests (% predicted value) as compared with control subjects: FVC, FEV1, FEV1 %, FEF25-75, FEF25-75%, DLCO, DLCO/VA, Pimax, Pimax% and Pemax%. Conclusion: These data indicate that pulmonary functions are effected in subclinical hypothyrodism. Therefore patients with or who are at high risk of having subclinical hypothyroidism, should be suubjected to evalutaion of pulmonary functions with simple spirometry.