Waterpipe use among people who smoke in rural Vietnam: Secondary analysis from the M2Q2 randomized clinical trial

Waterpipe (WTP) tobacco smoking is highly prevalent in Vietnam. WTP use is associated with higher nicotine exposure and increased risk of pulmonary and cardiovascular diseases. The aim of this study is to understand WTP use and how it may influence smoking behaviors and cessation.

We conducted a secondary analysis of data from the mHealth Messaging to Motivate Quitline Use and Quitting (M2Q2) randomized trial, which evaluated a mobile health peer-texting intervention in Northern Vietnam. Logistic and mixed-effects logistic regression was used to assess the association between WTP, CO-verified cessation, and Quitline use, after accounting for commune-level clustering and adjusting for demographic factors and randomization.

Among 749 male smokers (mean age: 42.7 years), 53% reported WTP use. Higher education (high school: adjusted odds ratio, AOR=0.61; CI: 0.43-0.86, college: AOR=0.47; CI: 0.30 - 0.73), and age >60 years (AOR=0.53; CI: 0.28-0.99) were inversely associated with WTP use, compared to smokers who only completed secondary school, and were aged <30 years, respectively. Compared to non-WTP users, WTP users smoked fewer cigarettes daily (p<0.001), smoked sooner after waking (p<0.001), spent more money weekly on tobacco products (p<0.001), and began smoking at an earlier age (p=0.02). WTP was not significantly associated with CO-verified cessation, and users had lower non-significant Quitline use.

WTP users differed from non-WTP users in demographic and smoking behaviors. WTP did not significantly affect CO-verified cessation, with a non-significant trend of reduced Quitline use, suggesting barriers to treatment uptake. Tailored cessation strategies that address WTP-specific challenges are needed to improve outcomes in this high-risk group.