Temporal trends in the incidence of infective endocarditis in patients with a prosthetic heart valve

Abstract

Objective: The incidence of infective endocarditis (IE) is increasing, as is the insertion of prosthetic heart valves. We aimed to examine nationwide temporal trends in the incidence of IE in patients with a prosthetic heart valve in Denmark from 1999 to 2018.

Methods: Using the Danish nationwide registries, we identified patients who underwent heart valve implantation (for other reasons than IE) between 1999 and 2018. Crude incidence rates of IE per 1000 person-years (PY) were computed in 2-year intervals. IE incidences were compared using sex-adjusted and age-adjusted incidence rate ratios (IRR) using Poisson regression across calendar periods (1999-2003, 2004-2008, 2009-2013, and 2014-2018).

Results: We identified 26 604 patients with first-time prosthetic valve implantation (median age 71.7 years (IQR 62.7-78.0), 63% males). The median follow-up time was 5.4 years (IQR 2.4-9.6). Patients in the time period 2014-2018 were older (median age of 73.9 years (66.2:80.3)), and with a higher burden of comorbidities compared with the time period 1999-2003 (median age of 67.9 years (58.3:74.5)) at the time of implantation. A total of 1442 (5.4%) patients developed IE. The lowest IE incidence rate was 5.4/1000 PY (95% CI 3.9 to 7.4) in 2001-2002, and the highest incidence rate was 10.0/1000 PY (95% CI 8.8 to 11.1) in 2017-2018 with an unadjusted increase during the study period (p=0.003). We found an adjusted IRR of 1.04 (95% CI 1.02 to 1.06) (p<0.0007) per two calendar-years increments. Age-adjusted IRR for men were 1.04 (95% CI 1.01 to 1.07) (p=0.002) per two calendar years increment, and for women 1.03 (95% CI 0.99 to 1.07) (p=0.12), with p=0.32 for interaction.

Conclusion: In Denmark, the incidence of IE increased during the last 20 years in patients with prosthetic heart valves.

Keywords: Endocarditis; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation.

Figure 1

Flow chart. Flow chart of the patient selection. IE, infective endocarditis.

Figure 2

Incidence rate of IE. The figure shows the incidence rate of IE following heart valve implantation/1000 person-years (PY) by calendar year intervals of two for the overall population. Error bars indicate 95% CI. IE, infective endocarditi.

Figure 3

Incidence rate ratio of IE. The incidence rate ratio of IE following prosthetic valve implantation from 1999 to 2018 per 2-year intervals. IRR 1.04 (1.02; 1.06), (p=0.0007) per 2-year interval. Each year interval is in reference to the year interval: 1999–2000. IE, infective endocarditis; IRR, incidence rate ratio.

Figure 4

Incidence rate of IE stratified by sex. The figure shows the incidence rate of IE following heart valve implantation/1000 PY by calendar year intervals of two subdivided by sex. Error bars indicate 95% CIs. IE, infective endocarditis, PY, person-year.

Figure 5

Incidence rate of IE stratified by age. The figure shows the incidence rate IE /1000 PY by calendar year intervals of two stratified by age group <70 and ≥70. Error bars indicate 95% CI. IE, infective endocarditis; PY, person-year.

Figure 6

Incidence rate of IE stratified by heart valve type. The figure shows the incidence rate IE /1000 PY by calendar year intervals of two stratified by mechanical and biological heart valves. Error bars indicate 95% CI. IE, infective endocarditis, PY, person-year.