The Epidemiology of Endocarditis in Manitoba: A Retrospective Study.

BACKGROUND

Recently, anecdotal evidence suggested an increase in infective endocarditis (IE) in Manitoba driven by an increasing proportion of patients with intravenous drug use (IVDU)-associated endocarditis. This study aimed to characterize the observed changing incidence and epidemiology of IE.

METHODS

This retrospective study evaluated consecutive patients >18 years old with an International Classification of Disease-10 diagnosis of IE who presented to a tertiary referral center in Winnipeg, Manitoba between January 1, 2004 and December 31, 2018. Data were obtained by individual review of paper and electronic medical records and entered into the Research Electronic Data Capture database. Mortality and hospital readmission data were acquired by linking Research Electronic Data Capture data to the Manitoba Centre for Health Policy, which prospectively maintains a comprehensive population-based health database.

RESULTS

A total of 612 cases of IE were identified. The incidence of IE increased from 2.03 per 100,000 in 2004 to 5.16 per 100,000 in 2018, with IVDU-associated cases increasing from 0.11 to 2.87 per 100,000. Left heart vegetations were most common in the non-IVDU group, whereas right-sided vegetations dominated in the IVDU group. All-cause mortality did not differ between IVDU and non-IVDU IE, despite a significantly younger age in patients with IVDU. The IVDU group showed a higher rate of endocarditis recurrence.

CONCLUSIONS

In this first study to examine the longitudinal incidence of IE in Manitoba, we showed that the incidence of IE has significantly increased over the last 15 years, with a contribution of IVDU-associated IE that has a high rate of mortality and disease recurrence.