Pneumology - Original Articles
17 September 2025
Early Access
Proportion and number of chronic obstructive pulmonary disease cases attributable to potentially modifiable risk factors in Morocco
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All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.
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Chronic obstructive pulmonary disease (COPD) is a major global health issue, especially in low- and middle-income countries, with significant mortality and economic impact. The study focuses on estimating the population attributable fraction (PAF) for modifiable risk factors, including smoking, secondhand smoke, occupational dust exposure, underweight, and tuberculosis history. The study aims to provide a rigorous assessment of these factors' contributions to COPD onset. Using national prevalence data and relative risk estimates from high-quality studies, the study calculated the PAF for modifiable COPD risk factors, including smoking and occupational dust exposure, applying Levin’s and Smoking-Attributable Mortality, Morbidity, and Economic Costs formulas. Confidence intervals were determined through the simulated Wald interval method. In Morocco, the PAF for tobacco-related COPD was 47% for men and 5% for women, with over 1.2 million preventable cases in men and about 54,000 cases in women. The PAF for second-hand smoke at home was estimated at 4% in men and 5% in women. In the workplace, this fraction was higher in men (7%) than in women (4%). Occupational exposure to dust accounts for 13% of COPD cases in men and 12% in women, totaling 335,000 and 142,000 avoidable cases, respectively. Underweight contributes to 5% of cases in men and 2% in women, while tuberculosis accounts for over 1% of cases in both genders. COPD is largely influenced by modifiable risk factors like smoking and occupational exposure to dust. By targeting these risk factors, policymakers can significantly reduce future COPD cases.
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Ethics approval
As this study is based solely on the analysis of data from existing literature and does not involve human participants, formal ethical approval was not required.How to Cite
“Proportion and Number of Chronic Obstructive Pulmonary Disease Cases Attributable to Potentially Modifiable Risk Factors in Morocco”. 2025. Monaldi Archives for Chest Disease, September. https://doi.org/10.4081/monaldi.2025.3377.
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