Gender differences in long-term survival of Medicare beneficiaries undergoing mitral valve operations

Background: Gender disparities in outcomes have been documented in cardiac surgery. Gender differences in long-term survival after mitral valve operations, especially in the elderly, are less well studied.

Methods: Using Centers for Medicare and Medicaid Services data, we identified 183,792 Medicare beneficiaries aged 65 years and older who underwent mitral valve repair or replacement from 2000 through 2009. The final study population included 47,602 Medicare fee-for-service beneficiaries undergoing isolated mitral valve operations. The outcomes studied were gender-specific operative mortality and long-term survival.

Results: Women were less likely to receive mitral valve repair (31.9% vs 44.0%, p < 0.0001). The hospital mortality rate was 7.7% for women vs 6.1% for men (p < 0.0001), reflective of a worse preoperative profile. Women undergoing repair had worse long-term survival than men (p = 0.0020) but survival was similar after risk adjustment (hazard ratio, 0.97; 95% confidence interval, 0.92 to 1.02, p = 0.2106). Compared with the United States population matched for age and sex, mitral repair restored life expectancy for men but not for women. Unadjusted and adjusted long-term survival was similar for men and women undergoing mitral valve replacement (p = 0.3653; hazard ratio, 0.99; 95% confidence interval, 0.96 to 1.02; p = 0.4847).

Conclusions: In this large comparative study of gender differences in mitral valve operations, elderly women had higher operative mortality and lower long-term survival. These differences appeared to be driven largely because women present for mitral valve operations later in the disease process. Mitral repair appeared to restore normal life expectancy for men but not for women. Future studies should examine the factors that influence physician referral to mitral valve operations for men and women.