Background: Previous studies have shown an association between height and colorectal cancer (CRC). None of those studies adjusted the association for known risk factors, such as diabetes mellitus and chronic exposure to aspirin/NSAIDs. Only two studies evaluated the risk among male individuals.
Methods: We conducted a nested case-control study using a large population-based medical record database from the UK. Studied cases had any CRC code after the age of 40 years. Participants with a known family history of CRC syndromes or inflammatory bowel disease were excluded from the study. For every case, up to four eligible controls matched for age, sex, practice site, and duration of follow-up before the index date were selected by incidence-density sampling. Height was defined as the last measurement before the index date. The odds ratios (ORs) and 95% confidence intervals (CIs) for CRC were calculated for height quartiles, as well as for every 10-cm increase in height, using conditional logistic regression analysis, and adjusted for potential confounders.
Results: A total of 9978 cases and 26 847 controls were identified. The adjusted OR for CRC in the participants at the highest compared with the lowest height quartiles was 1.25 for male (95% CI 1.14-1.37) and 1.25 for female (95% CI 1.12-1.39) individuals. The adjusted OR associated with each 10-cm increase in height was 1.10 (95% CI 1.05-1.15) for male and 1.16 (95% CI 1.10-1.23) for female individuals. The risk remained persistent when analyzing different age groups.
Conclusion: Height is an independent risk factor for CRC in both male and female individuals.