Older HIV-positive patients in the era of HAART: changing of a scenario

Most of the epidemiological features of older HIV-infected patients were determined before the introduction of HAART in 1996. Since then, highly active antiretroviral therapy (HAART) has been reported to have a less beneficial effect on the immunological outcome in older patients, with an apparent reduction in the intensity and the rapidity of the immunological response in most older patients. However, older age did not appear to significantly affect the long-term virological outcome of HAART-treated patients.

The authors used a prospective case-control study to determine the impact of HAART on the virological and immunological response in a cohort of older HIV-positive patients when confounding variables – adherence to therapy, side effects and non-HIV-related co-morbidities – were evaluated.

Patients age 50 or older and patients aged 20-35 who were given HAART regularly, with a follow-up of at least six months, were included as cases and controls respectively, ratio 1:2. Controls were matched by sex, year of HIV diagnosis and the presence of AIDS-defining conditions. Patients were considered regularly HAART-treated if they had been taking HAART for at least three months.

The researchers considered three outcomes: immunological success; virological success; and viro-immunological success defined as a CD4 T-lymphocyte count greater than 200 cells/mm3 and an HIV viral load less than 50 copies/ml, both conditions together, respectively, at the end of the follow-up. Investigators used a modified version of the Charlson co-morbidity index to assess the significance of non-HIV-related conditions.

The study compared 58 cases with 116 controls. The median age for cases was 57.5, 30.9 for controls. Seventy-six percent of participants in both groups were men; 48 percent were in stage C of HIV infection. The mean of CD4 T cells was significantly lower in cases, the study reports, whereas the mean of the HIV viral log load was similar in the two groups.

Cases had more co-morbid conditions than controls (44.8% versus 15.5%); one-third had cardiovascular diseases. Cases also had a higher mean Charlson index than controls. Researchers observed no statistically significant differences between the two groups in the type, number and duration of HAART regimens. Both groups had a high adherence to HAART. Frequent adverse reactions included dyslipidemia, digestive intolerance and lipodystrophy.

The investigators found immunological success in 69% of the cases and 79% of the controls. They observed a statistically significant reduction in the HIV viral load in both cases and controls comparing baseline with the end of the follow- up values.

Virological success occurred in 79% of cases and 72% of controls. Sixty-four percent of cases and 62% of controls showed viro-immunological success. Comparing mean baseline with the end of follow-up values, the authors found a statistically significant increase in CD4 T-cell numbers. The authors’ multivariate analysis showed that after adjustment for sex and Charlson index, no statistically significant difference existed between cases and controls for immunological, virological and viro-immunological success. They obtained similar results when they added HIV- and HAART- related variables to the model.

“In conclusion,” they noted, “an early diagnosis of HIV infection in older patients is mandatory because the use of HAART allows them to achieve the same viro-immunological response as younger individuals.”