Inflammation in Relation to Intensity and Duration of Cigarette Smoking Among People Living with HIV

Both inflammation and smoking are independent predictors of morbidity and mortality among people living with HIV (PLHIV). As smoking burden is likely to exacerbate inflammation, we tested the hypothesis that higher intensity and longer duration of smoking are positively associated with C-reactive protein (CRP, an inflammatory marker) among 284 PLHIV in Kathmandu, Nepal. We measured smoking status, intensity of smoking, smoking duration, and CRP concentrations. In total, 22.9% of never smokers, 24.3% former smokers, and 34.1% current smokers had high CRP (> 3 mg/l). The median intensity and duration of smoking were 12 (cigarettes/day) and 19 years, respectively. Intensity of smoking (beta for increase in number of cigarettes/day: β = 0.245; p = 0.017), smoking duration (beta for 1-year increase in smoking: β = 0.341; p = 0.013), and pack-years of smoking (beta for 1-pack-years of smoking increase: β = 0.351; p = 0.002) were each positively associated with CRP concentrations. While quitting is important, reducing the intensity and duration of smoking until quitting might be helpful in reducing the levels of inflammation, thereby in mitigating HIV-related harms.