Prevalence of hypothyroidism in adults: An epidemiological study in eight cities of India

Abstract

Background:Hypothyroidism is believed to be a common health issue in India, as it is worldwide. However, there is a paucity of data on the prevalence of hypothyroidism in adult population of India.Materials and Methods:A cross-sectional, multi-centre, epidemiological study was conducted in eight major cities (Bangalore, Chennai, Delhi, Goa, Mumbai, Hyderabad, Ahmedabad and Kolkata) of India to study the prevalence of hypothyroidism among adult population. Thyroid abnormalities were diagnosed on the basis of laboratory results (serum FT3, FT4 and Thyroid Stimulating Hormone [TSH]). Patients with history of hypothyroidism and receiving levothyroxine therapy or those with serum free T4 <0.89 ng/dl and TSH >5.50 μU/ml, were categorized as hypothyroid. The prevalence of self reported and undetected hypothyroidism, and anti-thyroid peroxidase (anti-TPO) antibody positivity was assessed.Results:A total of 5376 adult male or non-pregnant female participants ≥18 years of age were enrolled, of which 5360 (mean age: 46 ± 14.68 years; 53.70% females) were evaluated. The overall prevalence of hypothyroidism was 10.95% (n = 587, 95% CI, 10.11-11.78) of which 7.48% (n = 401) patients self reported the condition, whereas 3.47% (n = 186) were previously undetected. Inland cities showed a higher prevalence of hypothyroidism as compared to coastal cities. A significantly higher (P < 0.05) proportion of females vs. males (15.86% vs 5.02%) and older vs. younger (13.11% vs 7.53%), adults were diagnosed with hypothyroidism. Additionally, 8.02% (n = 430) patients were diagnosed to have subclinical hypothyroidism (normal serum free T4 and TSH >5.50 μIU/ml). Anti – TPO antibodies suggesting autoimmunity were detected in 21.85% (n = 1171) patients.Conclusion:The prevalence of hypothyroidism was high, affecting approximately one in 10 adults in the study population. Female gender and older age were found to have significant association with hypothyroidism. Subclinical hypothyroidism and anti-TPO antibody positivity were the other common observations.

Effects of thyroid hormone replacement on glycated hemoglobin levels in non diabetic subjects with overt hypothyroidism

“…Indeed studies in our country show that overt hypothyroidism is found in 3.9% to 10.95% of the general population (16,17). These prevalence rates are much higher than that found in the Western population, where the prevalence of overt hypothyroidism is only 0.3-0.4% of the adult population (18,19).…”

Study of Antithyroid Peroxidase Antibodies in People with Normal Range Thyroid Stimulating Hormone

“…This gives evidence that autoimmune mechanisms appear to play an etiological role in a significant proportion of patients. 16 There is also another study which is similar to the present study in which they selected a group of people with high normal and low normal TSH to study the TPOAb levels, and found out that around 3% of the low normal TSH group was anti TPO positive, while 18.6% of the high normal TSH group had a positive test for antiTPO. 17 And from their study they suggested to lower the upper limit of TSH to 3.49 IU/ml so that about 20% more patients can be identified as hypothyroid with the help of suggesting TPOAb check.…”

“…16 And in their study the prevalence of hypothyroidism was high, affecting approximately one in 10 adults in the study population. Subclinical hypothyroidism and anti-TPO antibody positivity were observed in their study.…”

Thyroid Function Status in Indian Adult Nonpregnant Females in Ranchi, India

“…4 In a recent multicity study, the prevalence of overt undiagnosed clinical hypothyroidism was 3.5% and that of subclinical hypothyroidism was 8.5%. 16 In the Puducherry study, 12.5% of women who are in the age group above 55 years had subclinical hypothyroidism. 4 In our study, 13% of the women who are above 40 years of age showed biochemical evidence of subclinical hypothyroidism.…”