Trends and socioeconomic inequalities in amenable mortality in Switzerland with international comparisons

BACKGROUND Amenable mortality is a composite measure of deaths from conditions that might be avoided by timely and effective healthcare. It was developed as an indicator to study health care quality. METHODS We calculated mortality rates for the population aged 0-74 years for the time-period 1996-2010 and the following groups of causes of death: amenable conditions, ischaemic heart diseases (IHD, defined as partly amenable) and remaining conditions. We compared the Swiss results with those published for 16 other high-income countries. To examine the association between amenable mortality and socioeconomic position, we calculated hazard ratios (HRs) by using Cox regression. RESULTS Amenable mortality fell from 49.5 (95% confidence interval [CI] 48.2-51.0) to 35.7 (34.6-36.9) in males and from 55.0 (53.6-56.4) to 43.4 (42.2-44.6) per 100 000 person-years in females, when 1996-1998 was compared with 2008-2010. IHD mortality declined from 64.7 (95% CI 63.1-66.3) to 33.8 (32.8-34.8) in males and from 18.0 (17.2-18.7) to 8.5 (8.0-9.0) in females. However, between 1996-1998 and 2008-2010 the proportion of all-cause mortality attributed to amenable causes remained stable in both sexes (around 12% in males and 26% in females). Compared with 16 other high-income countries, Switzerland had the lowest rates of amenable mortality and ranked among the top five with the lowest ischaemic heart disease mortality. HRs of amenable causes in the lowest socioeconomic position quintile were 1.77 (95% CI 1.66-1.90) for males and 1.78 (1.47-2.16) for females compared with 1.62 (1.58-1.66) and 1.38 (1.33-1.43) for unamenable mortality. For ischaemic heart disease, HRs in the lowest socioeconomic position quintile were 1.76 (95% CI 1.66-1.87) for males and 2.33 (2.07-2.62) for females. CONCLUSIONS Amenable mortality declined substantially in Switzerland with comparably low death rates for amenable causes. Similar to previous international studies, these Swiss results showed substantial socioeconomic inequalities in amenable mortality. Proportions of amenable mortality remained constant over time and patterns of inequalities observed for amenable causes in men did not substantially differ from those observed for non-amenable causes of death. Additional amenable mortality research is needed to better understand the factors contributing to mortality changes and social inequalities including information on disease characteristics and health care supply measures.