Sex-specific analysis of haemodialysis prevalence, practices and mortality over time: the Austrian Dialysis Registry from 1965 to 2014

Background Despite a higher prevalence of chronic kidney disease among women, more men than women start renal replacement therapy (RRT). We hypothesized that gender differences in health care access exist and therefore aimed at determining whether characteristics and outcomes of haemodialysis patients over time differ by sex. Methods We studied all 28323 adults who began haemodialysis during 1965-2014 in the Austrian Dialysis Registry, analysing trends in patient characteristics by sex and decade with mortality (via Cox regression), which was compared with the mortality of the Austrian general population. Results More men than women started haemodialysis (60.1% men versus 39.9% women overall), with minor differences among decades and age groups. The male:female mortality rate ratio in the general population ranged from 1.2 to 2.4 for age groups >18years and in haemodialysis patients ranged from 0.80 to 1.3 (closer to 1 than in the general population, but consistently >1 in Decades 3-5). In recent decades, diabetes and hypertension replaced glomerulonephritis as the primary cause of end-stage renal disease in both men and women. Interaction analyses showed the mortality risk associated with haemodialysis access (only recorded in Decade 5) was significantly lower for men than for women. Conclusions The male:female mortality rate ratio and the proportion of women starting haemodialysis were remarkably stable, which does not support the hypothesis of gender differences in health care/haemodialysis access or could imply that such differences might have persisted over decades. Future research should expand to other countries and other forms of RRT.