AIDS Survival: Major Improvement Documented
A study of 1255 patients with at least one CD4 count under 100, published last week in The New England Journal of Medicine, found that by the second quarter of 1997, the AIDS death rate had decreased to less than a third of what it had been in 1995; opportunistic infection rates decreased even more.1 During this time the use of prophylaxis against opportunistic infections did not change much, but combination therapy including a protease inhibitor increased from 2% to 82%. Various statistical analyses all pointed to the change of treatment, especially combination regimens with protease inhibitors, as the reason for the decreased death and illness. (For example, when differences in treatment were included in the statistical model, the calendar year no longer predicted survival differences--indicating that treatment, not other factors that may also have changed over time, most likely accounted for the survival difference.)This study did not analyze the effect of NNRTIs such as nevirapine or delavirdine, which were not widely used when most of these data were being collected.
Other findings:
Patients with private insurance were more likely to get the protease inhibitor combination treatments, and they had better survival, than those who were covered by public programs or who paid for treatment themselves. This difference lessened over time, apparently as public clinics also began using protease inhibitors. In 1995, the death rate per 100 person years (for these patients who had at least one CD4 count under 100) was 46.9 for persons with Medicaid, vs. 24.4 for those with private insurance; by the second quarter of 1997, these death rates had fallen to 9.2 with Medicaid vs. 7.7 with private insurance.
Among patients who did receive combination therapy, the death rate was 1.5 times as much (50% higher) for those whose combinations did not include a protease inhibitor, than for those whose combinations did. (Patients on monotherapy did worse, and those with no antiretroviral therapy had the worst survival of all.)
Different sites varied greatly in how rapidly they began to use protease inhibitors. Among the nine sites in eight U.S. cities analyzed for this study, the difference was greatest in the first quarter of 1996, when 6% of the patients at one site were using protease inhibitors, vs. 71% at another site. (By the second quarter of 1997 the difference had narrowed to a low of 40% vs. a high of 95% use of protease inhibitors in these patients.)
The use of protease inhibitors did not differ significantly by race, sex, ethnic group, or age. However, injection drug users were less likely to receive them.
The authors believe the patients in this study are "reasonably representative of patients with HIV in the United States." They conclude, "Our data suggest that an intensive combination drug-therapy regimen that includes a protease inhibitor should be considered the standard of care for patients with advanced HIV infection."
References
1. Palella FJ, Delaney KM, Moorman AC, and others. Declining morbidity and mortality among patients with advanced human immunodeficiency virus infection. The New England Journal of Medicine. March 26, 1998; volume 338, number 13, pages 853-860.
