Development of a Medicare Health Outcomes Survey Deficit-Accumulation Frailty Index and Its Application to Older Patients With Newly Diagnosed Multiple Myeloma

Purpose: To develop a frailty index using the Rockwood Accumulation of Deficits approach for the Medicare Health Outcomes Survey (MHOS) and apply it in a subset of older patients with newly diagnosed multiple myeloma. Methods: Data from 2,692,361 patients without cancer, > 66 years of age, in SEER-MHOS linked databases between 1998 and 2009 were analyzed. A frailty index was constructed, resulting in a 25-item scale; cutoff values were created for individuals classified as frail. This frailty index was then applied to 305 patients with newly diagnosed myeloma in the database to predict overall survival. Results: In the derivation cohort of patients without cancer, the median age was 74 years and the mean frailty index was 0.23 (standard deviation, 0.17). Among patients without cancer, each 10% increase in frailty index (approximately three to four more deficits) was associated with a 40% increased risk for death (adjusted hazard ratio, 1.397; 95% CI, 1.396 to 1.399; P < .001). In the cohort of patients with newly diagnosed myeloma, the median age was 76 years an d the mean frailty index was 0.28 (standard deviation, 0.17). Each 10% increase in frailty index was associated with a 16% increased risk for death (adjusted hazard ratio, 1.159; 95% CI, 1.080 to 1.244; P < .001). Fifty-three percent of patients with multiple myeloma were considered frail. The estimated median overall survival of patients considered frail was 26.8 months, compared with 43.7 months (P = .015) for those who were not. Conclusion: The MHOS-based frailty index was prognostic for patients with multiple myeloma in predicting overall survival.