Thyroid dysfunction in patients on antiretroviral therapy: A perspective from southern India

Thyroid dysfunction in patients with human retroviral infection has been reported but the prevalence of thyroid function abnormalities in patients on highly active antiretroviral therapy (HAART) has not been studied. We aimed to assess the prevalence of thyroid dysfunction and autoimmunity (antithyroid peroxidase auto-antibodies [TPO-Ab]) in patients on first-line HAART, identify risk factors for thyroid dysfunction and determine any association of thyroid dysfunction with HAART.

We screened and enrolled consecutive patients from the outpatient department if they were (i) diagnosed with HIV infection (enzyme-linked immunosorbent assay); (ii) aged more than 18 years; (iii) on HAART for 1 year or more; and (iv) clinically stable with no evidence of any acute illness in the past 2 months. We excluded patients who were on drugs that affect thyroid function. Thyroid function tests and CD4 counts were done.

A total of 159 patients on firstline HAART were included in the study. Their mean (SD) age was 43.3 (10) years and duration of HAART was 44.4 (33.54) months. The mean CD4 count was 502.8 (274.45). Forty-seven patients (29.6%) had thyroid dysfunction. TPO-Ab positivity was noted in 6 patients. No association was seen between thyroid dysfunction and any type of regimen or drug. There was a significant negative correlation between CD4 counts and thyroid-stimulating harmone (TSH) suggesting that thyroid dysfunction may be more prevalent when immunity is low.

There is a high prevalence of thyroid dysfunction, predominantly subclinical hypothyroidism, in patients on HAART. Thyroid autoimmunity is low in this subset of patients. Lower immunity is associated with higher TSH levels. Larger longitudinal studies are required to determine the course of hypothyroidism in patients on HAART.