May 10, 2006

What a Drag: Smoking and HAART Butt Heads

Smoking is bad for your health—that’s not news. But the nearly 70% of people with HIV who light up on a regular basis might be interested to know about a new study showing that smoking may also reduce the benefits of HIV meds. “It’s not uncommon to resort to smoking to deal with the stresses of life with HIV,” says lead investigator Joseph Feldman, DrPH, of SUNY Downstate Medical Center in Brooklyn. “But women who were smoking tended to have a less favorable result from being on HIV treatment.”

The new findings, involving 924 women enrolled in the ongoing Women’s Interagency HIV Study (WIHS), showed that positive women who smoked while on treatment had inferior immune responses after more than seven years on treatment and were 36% more likely to get AIDS-related diseases than their non-smoking peers. While the risk of AIDS-related death was no different, the smokers were 53% more likely to die overall.

The effects of smoking on people with HIV haven’t gone unnoticed in the past. Earlier research blamed cigarettes for weakened immune systems—not to mention the higher risks of lung cancer, heart disease, osteoporosis in women and impotence in men that affect negatives too. But the new analysis, reported in the June 2006 issue of The American Journal of Public Health, is believed to be the first to specifically examine the impact on highly active antiretroviral therapy (HAART), the “combos” of current HIV treatment.

So how does smoking sabotage the benefits of HIV treatment? The researchers believe there’s a medical explanation and hope to pinpoint it in further studies. But meantime, there are theories. “It may be that smoking just causes other problems—a sort of cumulative burden,” suggests Feldman, “or that smoking directly interferes with a mechanism of HAART and renders it less effective.”

The researchers corrected for factors that could otherwise have skewed their findings, such as the possibility that smokers might be “risk takers” and therefore likely to adhere to their meds or the fact that the smokers in the study were disproportionately injection-drug users, who often have extra health problems. Gender itself is not necessarily a factor; the new findings may apply to men as well. “The data suggests that the influence really is in the immune system,” says Kathy Anastos, MD, principal investigator of the Bronx, New York branch of WIHS.

Smoking is just one of a multitude of health isues that HIV researchers are looking at with greater concern as positive people live longer. “[People with HIV] are dying from non-HIV-related causes,” says Mardge Cohen, MD, a doctor in Chicago whose patients include smokers with HIV. “They’re much more than just the virus.”

Taking a broader view and studying health problems over the long term throws a different light on the value of preventing such problems—in this case, keeping positive people from starting smoking in the first place and helping all ages to quit. In fact, says Anastos, based on the findings of this study, “Providing treatment for smoking cessation is one of the most important things we can do for people who respond well to HAART.”