Gender difference in mitral valve disease: Where is the bias?

In the last decade, gender medicine has gained in importance in the management of cardiovascular disease, as several studies demonstrated substantial differences between men and women in terms of disease characteristics, response to treatment and prognosis. However, for most cardiovascular disease, it remains unclear whether this gender difference is due to true biological differences or to a sex bias in medical care, with which women would be less likely to receive appropriate screening and prevention strategies, timely diagnosis and guidelines-based therapy. In this volume of the European Journal of Preventive Cardiology, Kislitsina et al.1 compared general disease characteristics, treatment and outcome between men and women undergoing mitral valve surgery and included in the Cardiovascular Research Database of the Clinical Trial Unit of the Bluhm Cardiovascular Institute at Northwestern Memorial Hospital. It is therefore a single centre study, and specifically performed in a tertiary-care referral hospital, whose results might be less representative of the general medical practice as compared with data coming from multi-centre registries, which also reported trends in mitral valve surgery and in post-operative outcome.2,3 However, the study population was relatively large (N≈1500) and patients were included between 2004 and 2017, therefore well reflecting modern clinical practice and current standard of medical and surgical treatment. Previous studies in fact showed that in the last decades a significant shift in mitral valve disease aetiology has occurred, with less rheumatic mitral valve disease and more frequent degenerative as compared with ischaemic mitral regurgitation; furthermore, surgical techniques have substantially improved, with significantly better post-operative and long-term outcome.2,4 It is therefore of clinical importance to assess, as such as in the study of Kislitsina et al., whether gender disparities are still true in the current clinical scenario.