Lung transfer components in hyperthyroidism.

ABSTRACT

Pulmonary functions were studied in twenty hyperthyroid non smoker patients. Their FVC, PEFR and MVV were significantly lowered while FEV1/FVC% and EFR25-75% were normal. Amongst the diffusion functions, Tlco, Dm and VA were reduced and VC increased, though these changes were not statistically significant. After the achievement of euthyroid state, statistically significant increase was seen in FVC, PEFR, MVV, Tlco120, Dm and VA with significant decrease in Vc from the basal levels. FEV1/FVC% and EFR25-75% were not affected. These observations suggest that the principal abnormalities in pulmonary functions in the hyperthyroid state are increased pulmonary capillary blood volume and respiratory myopathy, which are reversed as euthyroid state is achieved.