NEW YORK (Reuters Health) – Patients with HIV who are not started on highly activate antiretroviral therapy (HAART) until their CD4+ cell count dips below 200 cells/mm³ may not achieve a normal CD4+ cell count, even after a decade of otherwise effective treatment, US investigators report in the March 15 issue of Clinical Infectious Diseases.

“A persistently low CD4+ cell count during treatment is associated with increased risk of both AIDS- and non-AIDS-related events (e.g., cardiovascular disease, liver disease, and cancer,” Dr. Steven G. Deeks at the University of California, San Francisco, and co-authors point out. Only after counts are maintained above 500 cells/mm³ is a patient considered to have a normalized immune status.

The research team evaluated 366 patients who had maintained plasma HIV RNA levels no higher than 1000 copies/mL for at least 4 years after starting therapy. Median follow-up was 7.5 years, with nearly a quarter of subjects followed for more than 10 years.

Almost all patients (95%) who started therapy with a CD4+ cell count at least 300 cell/mm³ were able to attain a CD4+ cell count at least 500 cell/mm³, the team reports. However, “44% of patients who started with a CD4+ cell count less than 100 cell/mm³ and 25% of patients who started therapy with a CD4+ cell count of 100-200 cell/mm³ were unable to achieve a CD4+ cell count greater than 500 cell/mm³.”

Dr. Deeks and colleagues say “novel immune-based therapeutic approaches may be necessary to restore immunocompetence in these individuals.”

In a related editorial, Drs. Boris Julg and Bruce D. Walker at Massachusetts General Hospital, Charlestown, note that major treatment guidelines recommend starting antiretroviral therapy when CD4+ cells counts fall below 350 cells/mm³ — difficult advice to follow in impoverished countries.

“However,” they predict, “adequate early therapy, leading to more-complete immune reconstitution, may save resources because of the resulting lower incidence of opportunistic infections and reduced need for medical care.”

Reference:
Clin Infect Dis 2009; 48:787-797.