Design: Systematic review and meta-analysis of cohort studies
Population: 39 cohorts: 536,399 CAYA cancer survivors and 1,810,572 cancer-free peers
Primary outcome: Incident cardiovascular disease
Effect: RR 1.99 (1.66–2.40); childhood cancer RR 2.48 (1.87–3.27); young adult RR 1.61 (1.37–1.88)

A meta-analysis in JAMA Pediatrics (28 September) pooled 39 cohort studies including 536,399 people who had cancer in childhood, adolescence or young adulthood and 1.8 million cancer-free peers.

Survivors had about twice the risk of cardiovascular disease overall (RR 1.99, 95% CI 1.66 to 2.40), an estimated 90 extra events per 1,000 survivors. The relative risk was higher for cancer in childhood (RR 2.48) than in young adulthood (RR 1.61). It narrowed with longer follow-up but remained raised beyond 20 years, and held in high-quality and population-based analyses.

For paediatricians and the GPs who inherit these patients, the message is that cardiovascular risk follows a childhood cancer into adult life. Survivorship care should include blood pressure, lipids, glucose and weight, and knowledge of which treatments — anthracyclines and chest radiation in particular — carry specific cardiac surveillance needs.

Keep a treatment summary for every childhood cancer survivor, including anthracycline dose and radiation fields.
Check blood pressure, lipids, glucose and weight regularly through survivorship.
Follow survivorship guidance for echocardiographic surveillance after cardiotoxic treatment.
Hand over cardiovascular risk explicitly at transition to adult care.

Why it matters

Risk persists for decades, well past the point when survivors leave paediatric follow-up.

The statistics, in plain English

A risk ratio of 1.99 means about double the rate. The 90 extra events per 1,000 is an absolute estimate over the studies' follow-up and depends on baseline risk. These are cohort data, so part of the excess may reflect factors other than the cancer treatment.