Long-term Exposure to Walkable Residential Neighborhoods Reduces the Risk of Obesity-related Cancer in Women

Background and Aim Living in neighborhoods with higher levels of walkability has been associated with a reduced risk of obesity and higher levels of physical activity. Obesity has been linked to increased risk of 13 cancers in women. However, long-term prospective studies of neighborhood walkability (NW) and risk for obesity-related cancer are scarce. In this prospective study, we evaluated the association between average NW and risk of cancer. Methods In the New York University Women’s Health Study (NYUWHS), a prospective cohort with 14,274 women recruited between 1985 and 1991 in New York City and followed over nearly three decades, we geocoded residential addresses for each participant throughout follow-up. We calculated an average annual measure of neighborhood walkability across years of follow-up using data on population density and accessibility to destinations associated with geocoded residential addresses. We employed Cox proportional hazards models to assess the association between average NW and risk of overall and site-specific obesity-related cancers over a period of nearly three decades. Results Residing in neighborhoods with a higher walkability level was associated with a reduced risk of overall and site-specific obesity-related cancers. The hazards ratio (95% CIs) associated with a standard deviation increase in average annual neighborhood walkability was 0.88 (0.85-0.93) for overall obesity-related cancer, 0.89 (0.84-0.95) for postmenopausal breast cancer, 0.82 (0.68-0.99) for ovarian cancer, 0.87 (0.76-0.99) for endometrial cancer, and 0.68 (0.49-0.94) for multiple myeloma, adjusting for potential confounders at both the individual and neighborhood level. The association between NW and risk of overall obesity-related cancer was stronger among women living in neighborhoods with higher levels of poverty compared to women living in areas with lower poverty levels (p-value, interaction=0.006). Conclusions Our study highlights a potential protective role of NW in preventing obesity-related cancers in women. Keywords Neighborhood walkability, urban health, women's health, obesity-related cancer.