Risk factors of colorectal cancer among Saudi Population: Case-control study

Colorectal cancer (CRC) incidence and related mortalities have been steadily increasing in KSA over the past 20 years. CRC in the Kingdom of Saudi Arabia (KSA) population presents in younger ages and in more advanced disease states as compared to other countries. This study was aimed to determine factors (demographic, habitual, environmental, nutritional, and genetic) associated with CRC in Riyadh, KSA.

A matched case-control study conducted in the major hospitals in Riyadh (King Khalid university Hospital, King Faisal Specialist Hospital, Riyadh Military Hospital, Security Force Hospital, King Fahd Medical City). Here most of CRC cases are managed. The cases (n = 121) group included all recently diagnosed and pathologically confirmed Saudi cases of CRC identified during the period 1^st of January 2017 till 31^st of December 2018 who agreed to participate and fulfilled the inclusion criteria. A similar number of controls attending the study settings were selected consecutively from the clinics where cases were managed and matched on a 1:1 basis with cases based on age (+/-3 years) and gender. Data were collected using a structured questionnaire. Conditional logistic regression models were fitted to determine factors associated with risk of CRC.

This study included similar number of males and females in both groups: males 69 (57%) and females 52 (43%) in each group (Chi-square test P = 1.0). The mean (S.D) age in the cases group was 53.6 (S.D = 12.9) and 53.3 (S.D = 12.9) in the controls group (Student test P = 0.86). In the final multivariate conditional logistic regression model, variables independently associated with risk of colorectal cancer were body mass index (OR = 0.93; 95% CI 0.87-0.98; P = 0.011) employment status (inverse relation: OR = 0.33; 95% CI 0.14-0.77; P = 0.010), colon polyps (OR = 4.09; 95% CI 1.06-15.82; P = 0.041), and constipation (OR = 4.98; 95% CI 1.91-15.99; P = 0.001).

Factors associated with CRC in the major referral hospitals in KSA were colon polyps, chronic constipation, and unemployment. These factors should be considered when screening for patients at risk for CRC.