# Valvular Heart Diseases in Swedish Males and Females: A National Cohort Study

## TL;DR

This study found that Swedish males had a higher overall risk of valvular heart diseases but a lower risk of specific valve disorders compared to females.

## Contribution

The study provides a nationwide analysis of sex differences in valvular heart diseases using comprehensive data from Sweden.

## Key findings

- Males had a higher overall incidence rate of valvular heart diseases compared to females.
- Males had a lower risk of rheumatic mitral and tricuspid valve disorders compared to females.
- Males had a higher risk of nonrheumatic aortic valve disorders compared to females.

## Abstract

Sex differences in valvular heart diseases have been examined but rarely using a nationwide, comprehensive approach.

The aim of this study was to analyze the risk of different types of valvular heart diseases among males and females in Sweden.

This was a nationwide Swedish study of all individuals (N = 9,984,758; 4,969,472 males and 5,015,286 females). Valvular heart diseases were defined as at least 1 registered diagnosis in the National Patient Register between January 1, 1998, and December 31, 2018. Cox regression analysis was used to estimate HRs with 95% CIs of incident valvular heart diseases in males vs females. The Cox regression models were adjusted for age, comorbidities, and sociodemographic factors.

There were 111,315 male cases and 107,527 female cases, corresponding to overall incidence rates per 100,000 person-years of 68.6 (95% CI: 67.5-69.8) among males and 51.3 (95% CI: 50.6-51.9) among females. The HRs (with 95% CI) for males compared to females were for rheumatic mitral valve disorders 0.50 (0.46-0.53), for rheumatic aortic valve disorders 1.08 (0.99-1.18), for rheumatic tricuspid valve disorders 0.61 (0.57-0.66), for nonrheumatic mitral valve disorders 1.08 (1.06-1.10), for nonrheumatic aortic valve disorders 1.25 (1.24-1.27), for nonrheumatic tricuspid valve disorders 0.72 (0.68-0.77), and for pulmonary valve disorders 0.82 (0.75-0.90).

We observed certain sex differences, with, in general, a higher incidence rate among males of valvular heart disease diagnoses, but a lower risk of specific valve disorders. The underlying factors for the sex differences are unclear and need further investigation.