Cardiometabolic risk factors, physical activity, and postmenopausal breast cancer mortality: results from the Women\u2019s Health Initiative

Christina M Dieli-Conwright,Melinda L Irwin,Rowan T Chlebowski,Michael Lamonte,Aladdin H Shadyab,Joann E Manson,Rebecca A Nelson,Cynthia A Thomson,Michael S Simon,Candyce H Kroenke,Kerryn W Reding,Marian L Neuhouser,Lihing Qi,Rami Nassir,Joanne Mortimer,Kathy Pan,Tracy E Crane

doi:10.1186/s12905-022-01614-3

Abstract

BackgroundHigher physical activity levels are associated with lower breast cancer-specific mortality. In addition, the metabolic syndrome is associated with higher breast cancer-specific mortality. Whether the physical activity association with breast cancer mortality is modified by number of metabolic syndrome components (cardiometabolic risk factors) in postmenopausal women with early-stage breast cancer remains unknown.MethodsCardiovascular risk factors included high waist circumference, hypertension, high cholesterol, and diabetes. Breast cancers were verified by medical record review. Mortality finding were enhanced by serial National Death Index queries. Cox proportional hazards regression models were used to estimate associations between baseline physical activity and subsequent breast cancer-specific and overall mortality following breast cancer diagnosis in Women’s Health Initiative participants. These associations were examined after stratifying by cardiometabolic risk factor group.ResultsAmong 161,308 Women’s Health Initiative (WHI) participants, 8543 breast cancers occurred after 9.5 years (median) follow-up in women, additionally with information on cardiometabolic risk factors and physical activity at entry. In multi-variable analyses, as measured from cancer diagnosis, higher physical activity levels were associated with lower all-cause mortality risk (hazard ratio [HR] 0.86, 95% confidence interval [CI] 0.78–0.95, trend P < 0.001) but not with breast cancer-specific mortality (HR 0.85, 95% CI 0.70 to 1.04, trend P = 0.09). The physical activity and all-cause mortality association was not significantly modified by cardiometabolic risk factor number.ConclusionsAmong women with early-stage breast cancer, although higher antecedent physical activity was associated with lower risk of all-cause mortality, the association did not differ by cardiometabolic risk factor number.

Highlights

Higher physical activity levels are associated with lower breast cancer-specific mortality
We hypothesized that women with breast cancer having more metabolic syndrome components would be more likely to benefit from higher pre-diagnosis physical activity levels in terms of breast cancer mortality
Higher physical activity levels at entry were inversely associated with high waist circumference, history of diabetes, high blood pressure, and higher cardiometabolic composite scores (Table 2)

Summary

Introduction

Higher physical activity levels are associated with lower breast cancer-specific mortality. The metabolic syndrome is associated with higher breast cancer-specific mortality. Higher physical activity levels have been shown to influence the metabolic syndrome in women with breast cancer [5] and in other settings [6] where exercise programs significantly reduced metabolic syndrome components. It is unknown whether presence of the metabolic syndrome modifies the favorable physical activity influence on breast cancer. We hypothesized that women with breast cancer having more metabolic syndrome components would be more likely to benefit from higher pre-diagnosis physical activity levels in terms of breast cancer mortality

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Results

Discussion

Conclusion