March 11, 2003
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 ages 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.
Cases had more co-morbid conditions than controls (44.8 versus 15.5 percent); 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 percent of the cases and 79 percent 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 percent of cases and 72 percent of controls. Sixty-four percent of cases and 62 percent 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."
01.03.03; Vol. 17; No. 1: P. 128-131; Mario Tumbarello; Ricardo Rabagliati; Katleen de Gaetano Donati; Silvia Bertagnolio; Enrica Tamburrini; Evelina Tacconelli; Roberto Cauda