A case-control study of lung cancer in Casablanca,Morocco

Objective: To evaluate etiologic risk factors for lung cancer in Casablanca, Morocco. Methods: We conducted a hospital-based case–control study that included 118 incident lung cancer cases and 235 age-, sex- and residence-matched controls. We analyzed the data using matched univariate and matched and unmatched multivariate logistic regression analyses. Results: Active tobacco smoking and history of chronic bronchitis were the strongest risk factors for lung cancer in the matched logistic regression model. Multivariate odds ratio (OR) and 95% confidence intervals varied from 1.79 (0.47–6.79) for former light smokers to 26.07 (6.58–103.27) for current heavy tobacco smokers at the time of disease occurrence. Combined use of hashish/kiff and snuff had an OR of 6.67 (1.65–26.90), whereas the OR for hashish/kiff (without snuff) was 1.93 (0.57–6.58). History of chronic bronchitis had an OR of 4.16 (1.76–9.85). Other slightly increased risks of lung cancer were found for exposure to passive smoking (1.36; 0.71–2.62), occupational exposures (1.75; 0.84–3.63), use of candles for lighting (1.44; 0.42–5.01), and poor ventilation of the kitchen (1.22; 0.57–2.58). Conclusions: This study confirms known risk factors for lung cancer and uncovers potential new etiologic ones such as the role of hashish/kiff.