Subclinical Hypothyroidism refers to biochemical evidence of Thyroid hormone deficiency in patients who have few or no apparent clinical features of Hypothyroidism. In practical field, if the patients serum fT₄ is within normal limit but serum TSH is elevated then it is considered as Subclinical Hypothyroidism. So Subclinical Hypothyroidism resides in the same spectrum of clinical hypothyroidism In Hypothyroidism there is decreased muscle strength and this may affect Pulmonary functions accordingly.

Objective: To assess Pulmonary Functions in Subclinical Hypothyroidism cases to find out whether there is any significant impairment of lung functions.

Materials and Methods: The study was done in one of the Peripheral Medical Colleges of West Bengal. 100 subjects (50cases and 50 controls) were selected according to age BMI, Inclusion and exclusion criteria. Serum TSH and serum fT₄ were measured and spirometric measurement of lung functions were done.

Statistical analysis was done by SPSS-17 and P value < 0.001 was considered as statistically significant.

Result: All the spirometric parameters were significantly decreased in subclinical hypothyroidism as compared with the normal control group.

Keywords: subclinical hypothyroidism, serum TSH, serum fT_4, spirometric measurement of lung function.

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B Mukhopadhyay

Professor, Department of Physiology, Murshidabad Medical College, West Bengal, India