Meta-analysis of the association between health literacy and smoking

Introduction Numerous studies have reported associations between health literacy and smoking-related behaviors or issues. However, no literature review has been conducted to synthesize these associations. Therefore, this review aimed to assess the associations between health literacy and smoking-related behaviors or issues. Material and Methods We searched published literature in four electronic databases (PubMed, CINAHL Plus, Scopus, and Web of Science) from inception to 22 February 2021. The search was limited to articles written in English and published in scientific journals. The reference lists of identified articles and Google Scholar were also manually searched. The extracted data regarding the association between health literacy and smoking was subjected to meta-analysis using Review Manager software (Review Manager, version 5.4.1). The results of the meta-analysis are reported as a weighted odds ratios (ORs) with 95% confidence interval (CI). Heterogeneity and publication bias were assessed using the Cochrane chi-squared test and I 2 value, and the funnel plot, respectively. Results The initial database search yielded 1266 articles. Fourteen additional articles were obtained through a manual search. Finally, 66 articles were included in the analysis. The meta-analysis showed that 22 studies had a pooled OR (95% CI) for smoker of 1.49 (95% CI: 1.25–1.79) in the inadequate health literacy group, compared with the adequate health literacy group. There was a high heterogeneity (p<0.001, I 2 =80%). The visual inspection of the funnel plot showed evidence of publication bias. Moreover, previous studies reported that inadequate health literacy was significantly positively associated with a high possibility of current smoking compared with former smoking in those that had ever smoked and smoking relapse, and a low possibility of smoking cessation. Conclusions Improving health literacy may be useful to prevent smoking, promote smoking cessation, and avoid smoking relapse.