Thyroid dysfunction and its association with microvascular complications in patients with type 2 diabetes mellitus in south India

Background and aims: To study the prevalence of thyroid disorders and their association with microvascular complications among adult type 2 diabetes mellitus (T2DM) patients from south-coastal Andhra Pradesh, India METHODS: This cross-sectional study included 500 subjects with T2DM and was conducted in a tertiary health care center from south-coastal Andhra Pradesh. Participants previously diagnosed with thyroid disorders were excluded from the study.

Results: Thyroid dysfunction was observed in 98 (19.6%) subjects of which subclinical hypothyroidism (n = 66, 13.2%) was the most common. Subclinical hypothyroidism (SCH) was more frequent in obese patients (16.2% vs 7.6%, p = 0.007) and metformin users (9.6% vs 18.7%, p = 0.0044). Diabetic retinopathy (27.3% vs 8.9%, p = 0.001) was significantly more frequent in SCH patients than euthyroid T2DM patients.

Conclusion: Among T2DM patients from south-coastal Andhra Pradesh the prevalence of thyroid dysfunction, especially that of SCH was high; SCH was more frequent among obese and nonmetformin users and was associated was associated with increased risk of diabetic retinopathy.