Behavioral, familial and comorbid illness risk factors of colorectal cancer: a case control study

Introduction: Though colorectal cancer is a disease of public health importance, there is little evidence about risk factors of colorectal cancer in South Asians.

Objectives: We aimed to determine the behavioral, familial and comorbid illness risk factors for colorectal cancer among Sri Lankan adults.

Methods: We conducted this study among 325 participants (65 incident colorectal cancer cases, 130 hospital and 130 community controls) in five major health care institutions and communities in areas with high incidence in Sri Lanka. Behavioral, genetic and comorbid risk factors were assessed through an interviewer administered questionnaire. Risk factors were evaluated using bivariate and multivariate logistic regression.

Results: Adjusted logistic regression showed that frequent consumption of red meat (OR 3.06, 95% CI 1.26-7.43) and deep fried food (OR 2.54, 95% CI 1.22-5.39), hypertension ≥ 10 years (OR 3.3, 95% CI 1.3-8.6), colorectal cancer (OR 4.91, 95% CI 1.70-14.18) and other cancers (OR 3.0, 95% CI 1.14-7.81) among first degree relatives and age >50 years (OR 2.6, 95% CI 1.1 to 5.9) were significant risk factors compared to hospital controls. Frequent consumption of deep fried food (OR 4.2, 95% CI 1.7-10.1), being an ever smoker (OR 3.2, 95% CI 1.1-9.3), a current or former drinker (OR 5.4, 95% CI 1.1-27.8) and hypertension ≥ 10 (OR 5.1, 95% CI 1.7-15.6) were risk factors compared to community controls.

Conclusion: The behavioral, familial and comorbid illness risk factors identified should be considered in designing preventive strategies and identifying high-risk individuals for screening for colorectal cancer.