Abstract 11147: Associations of Physical and Mental-Health Related Quality of Life and Sleep Disturbance with Cardiovascular Disease Risk in Post-Menopausal Breast Cancer Survivors

Abstract

Introduction: Lower health-related quality of life (HRQoL) and greater sleep disturbance (SD) are associated with an increased risk of cardiovascular disease (CVD) in the general population. However, these associations may differ in breast cancer (BC) survivors who experience competing risks from cancer and its associated treatment. We examined whether physical or mental HRQoL (including individual subscales) or SD were associated with CVD risk in BC survivors. Methods: We conducted a longitudinal analysis in the Women’s Health Initiative (WHI) of post-menopausal women free of prevalent CVD at baseline and diagnosed with invasive BC during study follow-up from 1993 - 2010. CVD was defined as physician-adjudicated coronary heart disease or stroke. Physical and mental HRQoL, measured by the SF-36 Physical and Mental Component Scores (PCS and MCS, respectively), and SD, measured by the WHI Insomnia Rating Scale (IRS), were recorded post-BC diagnosis. Higher PCS and MCS scores indicate better HRQoL while higher IRS scores indicate worse SD. Time-dependent Cox proportional hazards models were used starting at BC diagnosis until 2010 or censoring adjusted for relevant confounders most proximal to or at BC diagnosis. Results: In 2,884 BC survivors, 157 developed CVD during a median follow-up of 9.5 years. After adjustment, higher PCS scores were significantly associated with a lower risk of CVD (Table). For a 5-unit difference, the risk of CVD was 9% lower for those with higher PCS scores (95% CI: 0.83, 0.99). Of the SF-36 sub-scales, higher scores on vitality, physical functioning, and general health were significantly associated with a lower risk of CVD (Table). Conclusions: In BC survivors, we found that better physical HRQoL was associated with lower CVD risk. While further research is needed to replicate these findings, our results support existing recommendations that women with breast cancer adopt health behaviors that promote physical health.