Smoking as a risk factor for oral candidiasis in HIV-infected adults.

Abstract

We aimed to examine if smoking is an independent predictor of oral candidiasis (OC) among HIV-1 infected persons. The cross-sectional part of this study evaluated 631 adult dentate HIV-1 seropositive persons examined for OC from 1995-2000 at the University of North Carolina Hospitals in Chapel Hill, NC. In the second part, from the above sample, a total of 283 individuals who were free of HIV-associated oral diseases at baseline were followed up for 2years to assess incident OC events. Data collected from medical record review, interview questionnaires, and clinical examinations were analyzed using chi-squared tests and t-tests. Logistic regression models were developed for prevalent OC employing the likelihood ratio test, whereas Poisson regression models were developed for assessing cumulative incidence of OC. These models included a variety of independent variables to adjust for confounding. Thirteen percent of participants had OC only; 4.6% had OC with Oral Hairy Leukoplakia; and 69.7% had neither. Smoking was associated with OC in all models [prevalent OC - current smokers: logistic regression - Odd ratio (95% CI)=2.5 (1.3, 4.8); Incident OC - current smokers: Poisson regression (main effects model) - Incidence rate ratio (95% CI)=1.9 (1.1, 3.8)]. Other Poisson regression models suggested evidence for effect modification between CD4 cell count and incident OC by smoking. Smoking is an independent risk factor for the development of OC in HIV-1 infected persons, and the risk of OC is modified by CD4 cell count which measures strength of the immune system.