Background: The availability of several therapeutic regimens has transformed HIV infection from a life-threatening disease into a chronic condition. Older patients (>50 years old) with HIV infection constitute a new treatment challenge in terms of the cumulative effects of ageing and antiretroviral therapy (ART).
Methods: The immunovirological effects and metabolic interactions of 48 weeks of ART in older patients followed up in three Infectious Diseases Units in Milan, Italy since 1994 were compared with those in younger controls aged 25-35 years.
Results: The 159 older patients and 118 controls enrolled in the study were comparable for HIV stage, baseline CD4 cell count and viral load but differed for mode of HIV transmission, comorbid conditions and related chronic treatments. Mean viral load decreased after 48 weeks of treatment by 2.6 log(10) HIV RNA copies/mL and CD4 count increased by 137.5 cells/microL in older patients, and similar values for immunovirological effects were obtained in the young controls. The relative risk (RR) of an abnormal test in older patients was 7.33 [95% confidence interval (CI) 4.36-12.36] for glucose, 1.73 (95% CI 1.45-2.07) for total cholesterol, 1.56 (95% CI 1.22-2.0) for high-density lipoprotein cholesterol, 1.26 (95% CI 1.02-1.56) for triglycerides, 6.48 (95% CI 4.36-9.66) for serum creatinine, and 0.45 (95% CI 0.35-0.58) for ALT. Moderate/severe liver and renal toxicities were recorded in the older patients but not in the controls. The tolerability of ART did not differ between the older patients and the controls. Thirty-nine new cardiovascular, endocrine-metabolic and neuralgic disorders (24.52 per 100 person-years) were diagnosed in the older patients and four (3.39 per 100 person-years) in the controls (P<0.0001).
Conclusions: Diseases induced by, or related to, the toxic effects of antiretrovirals interact with age-specific health profiles, raising new questions and challenges. Comparative epidemiological studies, research studies addressing specific questions and surveillance are needed to answer the questions that arise in clinical monitoring.