Abstract
IMPORTANCE: Breast cancer surgery, the most common cancer operation performed in nursing home residents, is viewed as a low-risk surgical intervention. However, outcomes in patients with high functional dependence and limited life expectancy are poorly understood. OBJECTIVE: To assess the overall survival and functional status changes after breast cancer surgery in female nursing home residents stratified by surgery type. DESIGN, SETTING, AND PARTICIPANTS: This study used Medicare claims from 2003 to 2013 to identify 5969 US nursing home residents who underwent inpatient breast cancer surgery. Using the Minimum Data Set Activities of Daily Living (MDS-ADL) summary score, this study examined preoperative and postoperative function and identified patient characteristics associated with 30-day and 1-year mortality and 1-year functional decline after surgery. Cox proportional hazards regression was used to estimate unadjusted and adjusted hazard ratios (HRs) of mortality. Fine-Gray competing risks regression was used to estimate unadjusted and adjusted subhazard ratios (sHRs) of functional decline. Statistical analysis was performed from January 2016 to January 2018. MAIN OUTCOMES AND MEASURES: Functional status and death. RESULTS: From 2003 to 2013, a total of 5969 female nursing home residents (mean [SD] age, 82 [7] years; 4960 [83.1%] white) underwent breast cancer surgery: 666 (11.2%) underwent lumpectomy, 1642 (27.5%) underwent mastectomy, and 3661 (61.3%) underwent lumpectomy or mastectomy with axillary lymph node dissection (ALND). The 30-day mortality rates were 8% after lumpectomy, 4% after mastectomy, and 2% after ALND. The 1-year mortality rates were 41% after lumpectomy, 30% after mastectomy, and 29% after ALND. Among 1-year survivors, the functional decline rate was 56% to 60%. The mean MDS-ADL score increased (signifying greater dependency) by 3 points for lumpectomy, 4 points for mastectomy, and 5 points for ALND. In multivariate analysis, poor baseline MDS-ADL score (range, 20-28) was associated with a higher 1-year mortality risk (lumpectomy: HR, 1.92 [95% CI, 1.23-3.00], P = .004; mastectomy: HR, 1.80 [95% CI, 1.35-2.39], P < .001; and ALND: HR, 1.77 [95% CI, 1.46-2.15], P < .001). After multivariate adjustment, preoperative decline in MDS-ADL score (lumpectomy: sHR, 1.59 [95% CI, 1.25-2.03], P < .001; mastectomy: sHR, 1.79; [95% CI, 1.52-2.09], P < .001; and ALND: sHR, 1.72 [95% CI, 1.56-1.91], P < .001) and cognitive impairment (lumpectomy: sHR, 1.27 [95% CI, 1.03-1.56], P = .02; mastectomy: sHR, 1.26 [95% CI, 1.09-1.45], P = .002; and ALND: sHR, 1.14 [95% CI, 1.04-1.24], P = .003) were significantly associated with 1-year functional decline across all breast cancer surgery groups. CONCLUSIONS AND RELEVANCE: For female nursing home residents who underwent breast cancer surgery, 30-day mortality and survival as well as 1-year mortality and functional decline were high. The 1-year survivors had significant functional decline. This study's findings suggest that this information should be incorporated into collaborative surgical decision-making processes.