Joint effect of fruit consumption with smoking and alcohol drinking on esophageal cancer: a case-control study

Objective To explore the join effect of fruit intake with smoking and alcohol drinking on esophageal cancer (EC) and to provide references for EC prevention.

Methods We conducted a hospital-based case-control study during a period from January 2010 through December 2016. Using a self-designed questionnaire, we surveyed a total of 1 181 pathologically diagnosed primary EC patients in Fujian Cancer Hospital and Zhangzhou Hospital Affiliated to Fujian Medical University and 1 196 gender and age frequency-matched non-tumor patients taking medical service in orthopedics departments of The First Hospital and Zhangzhou Hospital Affiliated to Fujian Medical University.

Results The results of multivariate unconditional logistic regression analysis demonstrated that fruit intake exerted a protective effect on EC, with a dose-response relationship between fruit intake frequency and the risk of EC (chi-square for trend = 193.60, P < 0.001) after adjusting for potential confounding factors such as gender, age, nationality, education level, marital status, and monthly income. The risk of EC decreased with the increment of fruit intake frequency (P < 0.001) regardless of smoking and alcohol drinking status. There was a multiplicative interaction between fruit intake and smoking and alcohol drinking (P = 0.040). For those neither smoking nor drinking alcohol, the participants eating fruit 1 – 3 times and 4 times or more per week had significantly decreased EC risks (odds ratio OR = 0.37, 95% confidence interval CI: 0.26 – 0.52 and OR = 0.16, 95% CI: 0.08 – 0.30) in contrast to the participants eating fruit less than one time per week. Compared with the non-smoker and non-alcohol drinker participants with the fruit intake less than one time per week, the smoker and alcohol drinker participants with the fruit intake less than one time and 1 – 3 times per week had significantly increased EC risks (OR = 6.28, 95% CI: 4.13 – 9.55 and OR = 1.68, 95% CI: 1.09 – 2.58). No significant difference in EC risk was observed between the smoker and alcohol drinker participants with the fruit 4 times or more per week and the non-smoker and non-alcohol drinker participants with the fruit intake less than one time per week (P > 0.05).

Conclusion Fruit intake is a protective factor against esophageal cancer. There is a multiplicative interaction between fruit intake and smoking and alcohol drinking and fruit intake could decrease esophageal cancer risk associated with smoking and alcohol drinking.