Cigarette Smoking is Associated with Faster HIV Disease Progression in Women on HAART

Smoking tobacco is associated with accelerated HIV disease progression and poorer response to antiretroviral therapy among women in the HAART era, according to a report in the June 2006 American Journal of Public Health. 

Researchers assessed the link between cigarette smoking and the effectiveness of antiretroviral therapy among participants in the multi-site Women's Interagency HIV Study (WIHS). The analysis included data from 924 primarily low-in come women, representing 72% of all women who started HAART between July 1995 and September 2003. Participants were followed for up to 7.9 (median 5.2) years. 

Results

In the WIHS cohort as a whole, 56% were current smokers and 16% were former smokers; the average amount smoked was about one pack per day, and the median duration of smoking was about 12 years.  Women who smoked were more likely to be African-American, to use illicit drugs, to have hepatitis C virus (HCV) coinfection, and to have had a prior AIDS diagnosis.  In a Cox regression analysis controlling for potential confounding factors including age, race, HCV infection, illicit drug use, previous use of antiretroviral therapy, and previous AIDS diagnosis, smokers on HAART had poorer virological response (HR = 0.79; 95% CI 0.67-0.93).  Smokers were more likely to experience virological rebound compared with nonsmokers (HR = 1.39; 95% CI 1.06-1.69)  Smokers also had poorer immunological response to HAART (HR = 0.85; 95% CI 0.73-0.99), and were more likely to experience immunological failure (HR = 1.52; 95% CI 1.18-1.96).  CD4 cell counts among smokers were on average lower during the follow-up period, despite being significantly higher at baseline.  Smokers were more likely than nonsmokers to develop AIDS-defining illnesses or receive an AIDS diagnosis (HR = 1.36; 95% CI 1.07-1.72).  Women who smoked had a higher overall risk of death compared with nonsmokers (HR = 1.53; 95% CI 1.08-2.19), but there was no significant difference in the risk of death due to AIDS specifically.   Smokers were less likely than nonsmokers to achieve optimal adherence to antiretroviral therapy; however, in an analysis that included only women who reported at least 95% adherence, smokers still had a significantly higher risk of AIDS-defining illness and death.

Conclusion

 Women on HAART who smoked were 36% more likely to progress to AIDS and 53% more likely to die than nonsmoking women. The authors concluded that, “Some of the benefits provided by HAART are negated in cigarette smokers.” 

The researchers said they were unsure why smokers were not more likely to die of AIDS specifically, but suggested this might be because women who smoked died of other causes before they could succumb to AIDS. 

Another recent study found that HIV positive women smokers are more likely to develop bacterial pneumonia, and smoking is also associated with greater likelihood of human papillomavirus (HPV) infection and cervical dysplasia and cancer. In addition, smokers with hepatitis C appear to have a greater risk of liver fibrosis progression.

07/7/06

Reference

J G Feldman, H Minkoff, M F Schneider, and others. Association of cigarette smoking with HIV prognosis among women in the HAART era. American Journal of Public Health 96(6): 1060-1065. June 2006.