# Association Between Physical Activity, Sedentary Behavior and Breast Cancer Risk Among Moroccan Women: A Multicenter Case–Control Study

## TL;DR

This study finds that higher levels of physical activity are linked to a lower risk of breast cancer in Moroccan women.

## Contribution

The study provides region-specific evidence on the association between physical activity and breast cancer risk in Moroccan women.

## Key findings

- Moderate physical activity is inversely associated with breast cancer risk, with a clear dose–response relationship.
- Active daily habits like walking and stair climbing are linked to lower odds of breast cancer.
- Frequent occupational fatigue and sweating are associated with increased breast cancer risk.

## Abstract

Purpose: Breast cancer (BC) incidence has been increasing rapidly in North Africa, including Morocco, yet evidence regarding modifiable lifestyle factors remains limited. This study aimed to assess the associations between physical activity, sedentary behavior, daily work habits, and BC risk among Moroccan women, addressing an important gap in regional data. Methods: We conducted a case–control study between 2019 and 2023, including 1400 histologically confirmed incident BC cases and 1400 matched controls. Physical activity was assessed across the lifespan, considering type, intensity, and duration. Associations with BC risk were estimated using adjusted odds ratios (aORs) and 95% confidence intervals (CIs). Results: Moderate physical activity was inversely associated with BC risk, showing a clear dose–response relationship. Compared with the lowest physical activity level, the highest quartile showed significantly lower odds of BC (aOR = 0.37 (95% CI: 0.29–0.47). Vigorous physical activity during young adulthood and mid-adulthood was similarly linked to reduced risk. Active daily habits, such as walking and regular stair climbing, were associated with lower odds, whereas frequent occupational fatigue and sweating were linked to increased risk. Conclusions: Our findings highlight a significant inverse association between physical activity and BC risk among Moroccan women. Notably, moderate PA and active daily habits like brisk walking are linked to lower odds of the disease. While these findings support the role of physical activity as an important factor associated with breast cancer prevention, the retrospective design of the study limits causal inference.