ObjectivesWith HIV treatment prolonging survival and HIV infection now managed as a chronic illness, quality of life (QOL) is important to evaluate in persons living with HIV (PLWH). We assessed at study entry the QOL of antiretroviral-naive PLWH with CD4 counts >500 cells/L in the Strategic Timing of AntiRetroviral Treatment (START) clinical trial. MethodsQOL was assessed with: (1) a visual analogue scale (VAS) for self-assessment of overall current health; (2) the Short-Form 12-Item Version 2 Health Survey((R)) (SF-12V2), for which responses are summarized into eight individual QOL domains plus component summary scores for physical health [the Physical Health Component Summary (PCS)] and mental health [the Mental Health Component Summary (MCS)]. The VAS and eight domain scores were scaled from 0 to 100. Mean QOL measures were calculated overall and by demographic, clinical and behavioural factors. ResultsA total of 4631 participants completed the VAS and 4119 the SF-12. The mean VAS score (with standard deviation) was 80.915.7. Mean SF-12 domain scores were lowest for vitality (66.3 +/- 26.4) and mental health (68.6 +/- 21.4), and highest for physical functioning (89.3 +/- 23.0) and bodily pain (88.0 +/- 21.4). Using multiple linear regression, PCS scores were lower (P<0.001) for Asians, North Americans, female participants, older participants, and those with less education, longer duration of known HIV infection, alcoholism/substance dependence and body mass index 30kg/m(2). MCS scores were highest (P<0.001) for Africans, South Americans and older participants, and lowest for female participants, current smokers and those with alcoholism/substance dependence. ConclusionsIn this primarily healthy population, QOL was mostly favourable, emphasizing that it is important that HIV treatments do not negatively impact QOL. Self-assessed physical health summary scores were higher than mental health scores. Factors such as older age and geographical region had different effects on perceived physical and mental health.