A systematic review and meta-analysis of lifestyle risk factors for small intestine adenocarcinoma.

Authors

Bennett C, Veal PG, Cantwell MM, Murray LJ, Lau C and Coleman HG.

Departments / Institutions

Cancer Epidemiology & Health Services Research Group, Centre for Public Health, Queens University Belfast, Northern Ireland.

Publication Date

Spring 2014

Introduction

Although the incidence of small intestinal adenocarcinoma (SIA) is low, rates are increasing and very little information regarding modifiable lifestyle risk factors is available. The aim of this study was to provide a systematic review of the evidence to date regarding lifestyle factors and SIA risk. Ovid MEDLINE, EMBASE and WEB OF SCIENCE were searched from 1950 to Week 1 October 2013 for relevant literature. Ten publications that reported on SIA risk in relation to alcohol intake (n=6), tobacco smoking (n=6), diet (n=5), BMI (n=3), and/or socioeconomic status (n=3) were retrieved. Results from studies examining alcohol, smoking and SIA risk were pooled using random-effects meta-analyses to produce relative risks (RR) and 95% confidence intervals (CI). The pooled SIA risk estimate for individuals in the highest versus lowest category of smoking was 1.24 (95% CI 0.71-2.17); n=5 studies. The summary risk estimate for individuals consuming the highest versus lowest category of alcohol intake was 1.51 (95% CI 0.83-2.75; n=5 studies) with significant increased risks emerging in sensitivity analysis with reduced heterogeneity (RR: 1.82, 95% CI: 1.05-3.15). With regards to nutritional factors, protective effects were suggested for high vegetable intake and maintaining a normal body weight, while increased risks were observed for those consuming the highest intakes of red meat and sugary drinks. Evidence on socio-economic status and SIA risk was equivocal. Further investigation of modifiable and lifestyle factors, particularly alcohol, smoking and diet, involved in the aetiology of this cancer is warranted in large consortial studies.