Diet, obesity and colorectal carcinoma risk: results from a national cancer registry-based middle-eastern study

Cancer of colon and rectum (colorectal) is one of the most common cancers worldwide. There is a scarcity of published data on the risk factors for colorectal cancer (CRC) from the Middle-Eastern countries specifically in Kuwait. Therefore, this matched case-control study sought to examine the risk factors associated with CRC in Kuwait.

One hundred and three histopathologically confirmed colorectal cancer cases were recruited from Kuwait Cancer Control Centre Registry. Two hundred and six controls matched with cases (2:1 ratio) on age, gender and nationality were selected from medical, ophthalmology, orthopedic and/ or surgical out-patient clinics at three main general hospitals in Kuwait. A structured questionnaire was used to collect the data from cases and controls through face-to-face interview. Adjusted matched odds ratios (mOR_adj) and their 95% confidence intervals (CI) were estimated using a multivariable conditional logistic regression model.

Multivariable conditional logistic regression model showed that cases were 4.3 times more likely to have had attainted obesity (BMI ≥ 30) in their lifetime compared to controls (mOR_adj = 4.3; 95% CI: 1.6-11.4). Compared to controls, cases rarely consumed fruits and vegetable (mOR_adj = 20.8; 95% CI: 4.4-99.5), tended to consume red meat 2-3 times a week (mOR_adj = 3.8; 95% CI: 1.6-8.7) or more than 4 times a week (mOR_adj = 9.4; 95% CI: 2.5-35.4). Reportedly cases compared to controls frequently (nearly every week) suffered from constipation (mOR_adj = 5.6; 95% CI: 1.9-16.5). However, CRC cases were less likely than controls to have been diagnosed in the past with hypercholesterolemia (mOR_adj = 0.3; 95% CI: 0.2-0.7) or diabetes mellitus type II (mOR_adj = 0.4; 95% CI: 0.2-0.8).

Obesity, excessive red meat consumption and infrequent fruits/vegetables intake were associated with an increased CRC risk. Overcoming identified pitfalls in dietary pattern and maintenance of healthy weight may help minimize CRC risk in Kuwait and perhaps other countries in the region. Further studies on genetic basis in conjunction with life styles and dietary factors may unravel their joint contributions to CRC risk and furnish tools for curtailing CRC risk in this and other similar populations.