The Epidemiology and Incidence of Cytomegalovirus Retinitis in the HIV Population in Singapore over 6 Years

Abstract

We report the epidemiologic trend of cytomegalovirus (CMV) retinitis among human immunodeficiency virus (HIV) patients in Singapore. Our study included a retrospective case series of HIV patients with newly diagnosed CMV retinitis (CMVR) at the Singapore CDC between 2005 and 2010. Demographics, symptoms, signs, and laboratory results, including CD4 counts, were collected. Prevalence and disease trends over time were measured. Of 224 new patients, 92.9% were male and 96.0% were on antiretroviral therapy (ART). Median age was 43.0 years, with a median CD4 count of 38.0 cells/μL at HIV diagnosis. There was a decline in CD4 counts at diagnosis, and median duration of ART initiation from HIV diagnosis generally was earlier. Overall incidence rate was 10.4 cases per 1000 person-years (PY) and the mortality rate was 19.4 per 1000 PY. Mean survival time was 160.2 months (95% confidence interval [CI] 150.3-170.2). The 25 patients who died during the study period were older at the time of CMVR diagnosis (P = 0.003) and had lower CD4 counts (P = 0.030). Worse prognoses were associated with older age (hazard ratio [HR] 1.06, 95% CI 1.02-1.10) and shorter time lag from HIV to CMVR diagnosis (HR 0.97, 95% CI 0.95-0.99). Patients who did not receive highly active antiretroviral treatment (HAART) had a higher mortality risk (HR 4.70, 95% CI 1.54-14.33). The incidence rate of CMVR was decreasing with earlier initiation of ART and lower CD4 counts at HIV diagnosis. Poor prognostic factors included older age, shorter time lag from HIV to CMVR diagnosis, and the absence of HAART. Constant ophthalmologic surveillance until immune reconstitution is recommended.