HIV-positive women taking highly active antiretroviral therapy (HAART) receive less benefit from the drugs if they smoke, no matter how much they smoke, according to a new study.

Dr. Joseph Feldman of State University of New York Downstate Medical Center and colleagues studied 924 U.S. women during an almost eight-year period. Those who smoked were 53 percent more likely than non-smokers to die during the study period. The smokers also had higher viral loads and lower CD4 counts. Compared with the non-smokers, the smokers were 36 percent more likely to be diagnosed with an AIDS-related illness like wasting syndrome or non-Hodgkin's lymphoma.

"Smoking had a fairly pervasive impact on the effect of HAART," said Feldman. A large proportion of women with HIV are smokers, he said, giving the findings widespread significance.

The study noted that smoking is much more common among people who are poor and have less education, the same groups that are at greatest risk of acquiring HIV in the United States.

"Smokers may be risk-takers who may not take the medication as carefully as non-smokers," Feldman said. "That was something we tried to piece out of the data, [but] even after we adjusted for risk-taking, smokers did less well on HAART." The study did not determine the link between smoking and AIDS drugs.

The study points up the need for smoking cessation efforts targeting women with AIDS, Feldman said.

The full study, "The Association of Cigarette Smoking with HIV Prognosis Among Women in the HAART Era -- A Report from the Women's Interagency HIV Study," is published in the American Journal of Public Health (2006;96.doi:10.2105/AJPH.2005.062745).