Surasak WiboonchutikulSomnuek SungkanuparphSasisopin KiertiburanakulLa Or ChailurkitAngkana CharoenyingwattanaWittaya WangsomboonsiriWasun ChantratitaBoonsong OngphiphadhanakulMahidol UniversitySawanpracharak Hospital2018-06-112018-06-112012-09-01Journal of the International Association of Physicians in AIDS Care. Vol.11, No.5 (2012), 305-31015570886154510972-s2.0-84867003886https://repository.li.mahidol.ac.th/handle/20.500.14594/14273Vitamin D plays role in bone health and the regulation of the immune system. A cross-sectional study of serum 25-hydroxyvitamin D (25[OH]D) levels was conducted among HIV-1-infected Thai patients to determine the prevalence and associated factors of low vitamin D levels (25[OH] D < 30 ng/mL) in tropical setting. 25-Hydroxyvitamin D was measured by liquid chromatography/tandem mass spectrometry. Of 178 patients, 58% received antiretroviral therapy at median (interquartile range [IQR]) duration of 7.4 (5.9-8.5) years. The prevalence of 25(OH)D deficiency ( < 20 ng/mL) and insufficiency (20-29.9 ng/mL) was 26.8% and 44.9%, respectively. Multivariate analysis showed that receiving efavirenz (EFV) was significantly associated with low vitamin D status (odds ratio = 3.60; 95% confidence interval, 1.06-12.15, P < .05). The mean (±standard deviation) level of 25(OH)D in patients receiving and not receiving EFV was 22.9 (6.6) and 28.6 (10.7) ng/mL, respectively, (P < .05). Low vitamin D status is common and needs to be assessed among HIV-infected patients including tropical residents especially when EFV is used. © SAGE Publications 2011.Mahidol UniversityImmunology and MicrobiologyMedicineArticleSCOPUS10.1177/1545109711432142