Risk factors associated with older age in treatment-naive HIV-positive patients.

BACKGROUND Older HIV patients are defined as aged 50 years and older. This group is a growing population in developed countries. In order to improve care for older HIV patients, we intended to gain insight into the specific features of transmission, epidemiology, immunology and antiretroviral treatment (ART) of this population. PATIENTS AND METHODS All patients from the RESINA cohort were analyzed, comprising 2,085 individuals at the beginning of 2010. RESINA is an ongoing study analyzing epidemiological and immunological data, resistance patterns and therapeutic data in treatment-naive HIV-positive patients from North Rhine-Westphalia, Germany. Patients are included in the RESINA cohort at the time of the intended start of ART. For statistical evaluation, we used χ(2) and Mann-Whitney U tests. RESULTS A total of 14.6% of patients in our cohort was above 50 years. Men were significantly more prevalent among older patients (86.8 vs. 78.6%; p < 0.001). The proportion of older patients was significantly higher in the heterosexual group (30%) as compared to bisexual (20%), homosexual (13%) and intravenous drug user (4%) modes of transmission (p < 0.001). When comparing ethnic groups, older patients were most often found among Caucasians (17 vs. 4% in other groups, p < 0.001). No significant difference for transmitted drug resistance patterns was found. The proportion of older patients with CDC stage A was significantly lower than with stages B or C (10 vs. 21 vs. 21%, p < 0.001). In older patients, changes of ART regimes were more frequent (p = 0.015) and the median CD4 cell count at the start of treatment was lower (176 vs. 200/μl, p = 0.017). After 72 weeks of ART, the relative increase of CD4 cells was significantly lower in older as compared to younger patients (200 vs. 231/μl, p = 0.017). CONCLUSIONS Our results provide insight into the epidemiology of HIV in the elderly. In our cohort, the typical older patient was a Caucasian male who had acquired HIV through heterosexual contact. The prognosis in older patients is worsened as a result of several unfavorable circumstances, such as delayed start of ART, more frequent treatment changes and diminished immune reconstitution. As a consequence, better strategies for more frequent HIV testing in patients at risk for HIV are needed, and ART should be offered to older patients at earlier time points and higher CD4 cell counts.