Associated mortality and time spent in hospital following mitral valve intervention for mitral regurgitation according to frailty status: a nationwide Danish study

AIMS: Little is known about how patient frailty affects mortality and hospitalization following mitral valve intervention for mitral regurgitation (MR).

METHODS AND RESULTS: Using Danish nationwide registries, we identified patients undergoing first-time mitral valve intervention for MR during the period 1996-2022. Patients were categorized as frail or non-frail based on the Hospital Frailty Risk Score. We assessed 1 year mortality with the reverse Kaplan-Meier estimator, and adjusted comparisons were computed using multivariable-adjusted Cox regression analysis. A composite outcome of death or time in hospital >14 days within 1 year was examined using multivariable-adjusted logistic regression analysis. A total of 7000 patients (90.0%) were considered non-frail (median age 67.0 years, 66.3% male) and 782 (10.0%) were considered frail (median age 71.0 years, 56.3% male). One year mortality was 8.2% among non-frail patients and 13.4% among frail patients (P-value <0.0001), but no statistically significant difference was observed [hazard ratio = 1.16, 95% confidence interval (CI): 0.88-1.54, reference: non-frail patients] in the adjusted analysis. Within the first year after mitral valve intervention, 42.8% of non-frail patients were never admitted, 42.1% were admitted for 1-14 days, 6.2% for 14-28 days, and 5.1% for >28 days. Among frail patients, the corresponding proportions were 26.6%, 46.3%, 9.1%, and 9.8%. In the adjusted analysis, frail patients were associated with higher odds of the composite outcome [odds ratio = 1.65 (95% CI: 1.37-2.00)].

CONCLUSION: Frail patients were associated with more time spent in hospital within the first year following surgery compared with non-frail patients, but no statistically significant difference was found in the 1 year mortality according to frailty status in adjusted analysis.