IAC: Older HIV Patients May Face More Adverse Effects

August 12, 2006

TORONTO -- HIV patients ages 50 and over do a better job controlling the virus but may need more help managing adverse effects and comorbidities.

TORONTO, Aug. 12 -- HIV patients ages 50 and over do a better job controlling the virus but may need more help managing adverse effects and co-morbidities, California researchers said here.

A year after starting highly active anti-retroviral therapy (HAART), those ages 50 and over are more likely to have fewer than 500 copies of viral RNA per milliliter of blood than patients ages 18 through 39, Michael Silverberg, Ph.D., of the Kaiser Permanente Medical Program in Oakland reported at the 16th International AIDS Conference.

At the same time, however, their immune system recovery - measured by the number of CD4-positive T-cells - tends to lag behind younger patients, Dr. Silverberg reported in two poster presentations analyzing more than 5,000 HIV-positive Kaiser Permanente health plan members who started HAART from 1995 through 2004.

Also, Dr. Silverberg and colleagues found, patients 50 and older are more likely to have metabolic, hematologic, and renal abnormalities than younger patients.

The better viral control is driven by better adherence to therapy, Dr. Silverberg said in an interview, but because older patients are taking medications faithfully, they're vulnerable to the associated adverse effects.

"Therapy adherence was really the only factor that explained the better virological control," Dr. Silverberg said. But because older patients were more adherent, they experienced more of the known side effects of the HAART drugs.

"It's a tricky balance they have to maintain," he said.

The findings came from a database analysis, reviewing the records of 5,079 patients who started HAART. Of those, 997 were 50 or older when they started therapy. The study found that, compared with those ages 18 to 39, those 50 and over:

  • Were more likely to have higher total cholesterol and glucose. The odds ratios were 1.63 and 2.91, respectively, with 95% confidence intervals ranging from 0.0 to 2.9 and from 1.94 to 5.0.
  • Had higher hemoglobin and neutrophil levels. The odds ratios were 1.79 and 1.51, respectively, with 95% confidence intervals ranging from 1.10 to 2.9 and from 1.01 to 2.2.
  • Had creatinine levels that were twice as high. The odds ratio was 2.14, with a 95% confidence interval ranging from 1.02 to 4.5.
  • Were more likely to have RNA viral levels of fewer than 500 copies per milliliter of blood a year after starting HAART. The odds ratio was 1.15, with a 95% confidence interval ranging from 1.05 to 1.27.

While the CD4 recovery lagged behind younger patients, Dr. Silverberg said, by the third year of therapy it had caught up. The delayed response, he said, is probably a function of the decline of the immune system with age.

While the study is retrospective, he said, it includes a large number of patients with detailed records over nearly a decade of treatment. Also, Dr. Silverberg said, it may contain the largest recorded cohort of patients starting HAART at the age of 50 or older.