Children with Kawasaki Disease Face Long-Term Cardiovascular Risks

Children with Kawasaki Disease (KD) have a continued increased risk of cardiovascular events for more than 10 years after their indexed hospital care for the inflammatory disease.

In new data presented at the American College of Rheumatology (ACR) Convergence 2020, a team of Canadian investigators reported findings which would implicate the need for long-term cardiovascular screening in a pediatric population that may be increased in coming years.

Led by Cal Robinson, MD, BSc, Pediatric Nephrology Resident at The Hospital for Sick Children and the University of Toronto, investigators aimed to build off recent work which showed incidence of the pediatric vasculitis has been significantly increased in Ontario over the past 2 decades.

More acutely, the research was inspired by a conversation Robinson had with parents in his first year of pediatric residency.

“Their child had been diagnosed with KD and was almost ready to be discharged from the hospital,” Robinson said in a statement. “They asked me whether their child would be at risk of heart disease later in life.”

Uncertain of the answer, Robinson and colleagues pursued assessment of published literature around cardiovascular outcomes in patients with Kawasaki Disease. They sought to define risks and timing of long-term cardiovascular events, as per diagnoses and procedures, among survivors, and to determine their risk of all-cause mortality.

“It’s very important that we better understand the cardiovascular risk after childhood KD,” Robinson said. “Earlier diagnosis provides opportunities for intervention, which may mitigate the risk of heart disease later in life.”

Investigators identified children aged 0-18 years old who survived hospitalization with a KD diagnosis in Ontario anytime between 1995-2018 though a series of population health administrative database algorithms. Only the first eligible hospitalizations for patients were included, and children previously diagnosed with KD were excluded from assessment, as well as non-residents of the province.

Robinson and colleagues matched Kawasaki Disease cases to 100 non-exposed controls by age, sex, and index year. Follow-up continued until either patient death or to March 2019—a maximum of 24 years.

Incidence rates, per 1000 person-years, and unadjusted hazard ratios (HRs) for major adverse cardiovascular events (MACE) were determined in the comparison between patients with KD and control cohorts during time periods up to >10 years.

Among the observed 4597 survivors of Kawasaki Disease, 746 (16.2%) experienced cardiovascular events, 79 (1.7%) experienced MACE, and 9 (0.2%) died in the median 11.1-year follow-up period. Ischemic heart disease (231 patients, 4.6 events per 1000 patient-years), arrhythmias (22, 4.5 per 1000), and hypertension (159, 3.1 per 1000).

Survivors of Kawasaki Disease were observed to be at greater risk of MACE versus control children at the 0-1 year, 1-5 year, and 5-10 year follow-up periods. Cardiovascular events overall were observed at greater likelihood in the infected population at 10-plus years follow-up. Cardiovascular events were experienced sooner among children with Kawasaki Disease, with their risk of events highest in the first year post-discharge (HR, 14.13; 95% CI, 12.57-15.89).

Percutaneous coronary intervention (PCI) or coronary artery bypass grafting was also significantly more likely among infected children (HR, 14.68; 95% CI, 7.73-27.88).

Despite such cardiovascular risks, investigators also observed a lowered long-term mortality risk among children to have had Kawasaki Disease. Overall, though, the findings emphasize the need for surveillance and risk-reduction strategies for survivors of the inflammatory disease.

“Cardiovascular risk reduction strategies should be implemented for all KD survivors, including healthy active lifestyle counselling and early intervention when cardiovascular risk factors are identified,” Robinson said.

The study, “Late Cardiovascular Outcomes in Children with Kawasaki Disease: A Population-based Cohort Study,” was presented at ACR 2020.