Height and risk of colorectal cancer: a meta-analysis
Several epidemiological studies have investigated the relationship between height and risk of colorectal cancer (CRC), but the results were inconsistent. Thus, a meta-analysis of observational studies was carried out to clarify this association. A literature search was performed in PubMed and Web of Science databases for all relevant studies up to 25 May 2016. The random-effects model was used to calculate the pooled relative risks (RRs) and restricted cubic spline model was adopted for the dose–response analysis. A total of 31 studies involving 13 077 848 participants with 93 818 cases were included. The pooled RR (95% confidence interval) of CRC for the highest versus the lowest category of height was 1.25 (1.18–1.32); the pooled RR was 1.32 (1.22–1.43) for colon cancer and 1.12 (1.05–1.19) for rectal cancer for the highest versus the lowest category of height. A nonlinear relationship was found between height and the risk of CRC in the dose–response analysis (Pnonlinearity=0.0024). This meta-analysis indicates that height is associated with an increased risk of CRC.