Trends in occurrence and 30-day mortality of infective endocarditis in adults: population-based registry study in Finland.

Objectives: Infective endocarditis (IE) is a life-threatening disease associated with significant mortality. We studied recent temporal trends and age and sex differences in the occurrence and short-term mortality of IE.

Design: Population based retrospective cohort study.

Setting: Data of IE hospital admissions in patients aged ≥18 years in Finland during 2005-2014 and 30-day all-cause mortality data were retrospectively collected from mandatory nationwide registries from 38 hospitals.

Outcomes: Trends and age and sex differences in occurrence. Thirty-day mortality.

Results: There were 2611 cases of IE during the study period (68.2% men, mean age 60 years). Female patients were significantly older than males (62.0 vs 59.0 years, p=0.0004). Total standardised annual incidence rate of IE admission was 6.33/100 000 person-years. Men had significantly higher risk of IE compared with women (9.5 vs 3.7/100 000; incidence rate ratios [IRR] 2.49; p<0.0001) and difference was most prominent at age 40-59 years (IRR 4.49; p<0.0001). Incidence rate varied from 5.7/100 000 in 2005 to 7.1/100 000 in 2012 with estimated average 2.1% increase per year (p=0.036) and similar trends in both sexes. Significant increasing trend was observed in patients aged 18-29 years and 30-39 years (estimated annual increase 7.6% and 7.2%, p=0.002) and borderline in patients aged 40-49 years (annual increase 3.8%, p=0.08). In older population, IE incidence rate remained stable. The overall 30-day mortality after IE admission was 11.3%. Mortality was similar between sexes, increased with ageing, and remained similar during the study period.

Conclusions: Occurrence of IE is increasing in young adults in Finland. Men, especially middle-aged, are at higher risk for IE compared with women. Thirty-day mortality has remained stable at 11%, increased with ageing, and was similar between sexes.