Effects of cigarette smoking and nicotine dependence on adherence to antiretroviral therapy among HIV-positive patients in Vietnam.

Cigarette smoking is increasingly recognized as an indicator for inferior adherence to antiretroviral therapy (ART) among HIV-positive patients. Given the limited body of work on this issue, we aimed to explore the relations between cigarette smoking, nicotine dependence, and ART adherence in Vietnam. A cross-sectional study of 1050 HIV-positive people was conducted from January to September 2013 in Hanoi (the capital) and Nam Dinh (a rural city). Adherence to ART during the last 30 days was measured by the 100-point visual analog scale (VAS). Smoking history and nicotine dependence (Fagerstrom Test of Nicotine Dependence) were self-reported by participants. Multiple logistic regression was performed to examine the association of current smoking and nicotine dependence with ART nonadherence. Using the established VAS cut point of 95 to indicate adequate adherence, the prevalence of ART nonadherence was 30.9%. Approximately 35.5% of the sample reported current smoking. No association between smoking status and ART nonadherence was found. However, participants with greater nicotine dependence (OR = 1.1, 95%CI = 1.0-1.2 per unit increase) were more likely to be nonadherent. Also, individuals who were female (OR = 1.70, 95%CI = 1.19-2.42), receiving ART in Nam Dinh (OR = 1.6, 95%CI = 1.1-2.4), and currently feeling anxiety (OR = 1.6, 95% CI = 1.2-2.1) had a higher likelihood of ART nonadherence. Additionally, current smokers reporting current pain (OR = 1.9, 95%CI = 1.2-3.1) were more likely to be nonadherent. Conversely, protective factors included living with a spouse/partner (OR = 0.5, 95%CI = 0.3-0.7) and having more than a high school education (OR = 0.4, 95%CI = 0.1-1.0). Given the high prevalence of suboptimal adherence and current smoking among HIV-positive patients, screening for smoking status and nicotine dependence during ART treatment may help to improve patients' adherence to medication. More efforts should be targeted to women, patients with mental health problems, and ART clinics in rural areas.