Endocrine Abstracts

Objective: Highly Active Antiretroviral therapy (HAART) has been associated with several endocrine abnormalities. Data concerning thyroid dysfunction in HIV are still controversial. The aim of this study was to investigate the prevalence of thyroid dysfunctions and their association with HAART and HIV-infection in a large cohort of HIV-infected patients.

Methods: A retrospective cross-sectional study was carried out involving HIV-infected patients whose thyroid-stimulating hormone (TSH) and thyroid hormones (fT3, fT4) were evaluated from 2007 to 2017. A large database containing clinical information was approved by the local ethical committee. Laboratory ranges were used to identify hypothyroid (TSH above the upper limit) and hyperthyroid patients (TSH below the lower limit). Age, sex, CD4 nadir and count, HAART and sodium levels were collected.

Results: Data from 1966 HIV-infected patients (69% males, 31% females; age 46±8 years; HIV-infection duration 31±9 years) were retrospectively analysed. Total hypothyroidism prevalence, including 70 patients already on levothyroxine therapy (3.6%), was 3.9%. Undiagnosed hypothyroidism was found in 89 (4.7%) patients (4.4% subclinical, 0.3% overt). Only 6 patients (0.4%) were hyperthyroid (0.3% subclinical, 0.1% overt). Hypothyroid subjects had been exposed to significantly longer HAART duration (P=0.02). TSH did not correlate with any of measured parameters.

Conclusions: Prevalence of undiagnosed thyroid dysfunctions in our cohort of HIV-infected patients seems to be lower compared to general population, except for subclinical hypothyroidism which is similar. Only HAART seems to be related to hypothyroidism even though TSH levels did not correlate with HAART duration. We speculate that disrupted immune competence can explain the reduced prevalence of thyroid dysfunctions, which are mainly due to autoimmune disease.