Prevalence of hypothyroidism in Assam: A clinic-based observational study

Introduction: Hypothyroidism is a common functional disorder of the thyroid gland. Despite extensive research, data on this subject are lacking from the northeastern part of India, which falls in the Sub-Himalayan goitrogenic belt. Therefore, we decided to study the profile of hypothyroidism in Assam, a northeastern state with the following objectives: to determine the prevalence of hypothyroidism and to describe the various modes of clinical presentation. Materials and Methods: The study was conducted at a clinic-cum-radioimmunoassay laboratory in Guwahati, Assam, from January to November 2011. Two thousand and four hundred fifty-six patients referred to our center from different parts of Assam were evaluated clinically and their thyroid profile was estimated. Antithyroid peroxidase (TPO) antibody was estimated in 1950 patients. Results: The prevalence of overt hypothyroidism was 10.9% (n = 267) and that of subclinical hypothyroidism was 13.1% (n = 321). Male:female ratio was 1:3. Among the cases of overt hypothyroidism, 247 (92.51%) were adult hypothyroids, 15 (5.62%) juvenile hypothyroids, and 5 (1.87%) cretins. The common presenting features of hypothyroidism were weakness (98%), lethargy (95%), dry and coarse skin (87%), and body ache (85%). Uncommon modes of presentation were pleural and pericardial effusion, low body weight, frequent motions, and palpitations. Postthyroidectomy and drug-induced hypothyroidism accounted for 2.38% cases each and postpartum hypothyroidism for 3.74% cases. Thirteen percent cases presented with goiter. The prevalence of anti-TPO antibody in the study population was 8.41%. Conclusion: Hypothyroidsm is no longer a rarity, and Assam is no exception to this phenomenon. A population-based epidemiological study of thyroid disorders in Northeast India is an urgent need.