Cardiovascular risks of chemo-immunotherapy for lung cancer: A population-based cohort study

•PD-1 inhibitors (PD1i) are effective alone or with chemotherapy for lung cancer.•Cardiovascular safety of PD1i-chemotherapy regimen (chemo-immunotherapy) is unknown.•PD1i and chemo-immunotherapy were compared in 713 patients with lung cancer.•Incidence of major adverse cardiovascular events was not different between regimens.•Major adverse cardiovascular events were uncommon amongst these patients. Despite their proven efficacy for treating lung cancer, the cardiovascular risks associated with programmed cell death protein 1 (PD-1) inhibitors and their combinations with chemotherapy (chemo-immunotherapy) are unclear. This study aimed to investigate these associations. This retrospective cohort study included Hong Kong patients with lung cancer receiving PD-1 inhibitors during 2013–2021. Patients with non-concurrent use of PD-1 inhibitors and chemotherapy, any use of tyrosine kinase inhibitors or other immunotherapy agents, and those with prior stroke, heart failure, or myocardial infarction were excluded. PD-1 inhibitors and chemo-immunotherapy were compared for major adverse cardiovascular events (MACE), a composite of cardiovascular mortality, heart failure, stroke, and myocardial infarction. All patients were followed up until the end of 2021. Inverse probability of treatment weighting was used to balance covariates between the two treatment groups. In total, 713 patients (333 PD-1 inhibitors users and 380 chemo-immunotherapy users) were analysed. Over a mean follow-up of 1.4 ± 1.3 years, 24 had MACE, with an observed incidence of 2.8 [1.6–4.8] events per 100 person-year for patients on PD-1 inhibitors, and 2.1 [1.2–3.8] per 100 person-year for patients on chemo-immunotherapy. No significant between-group difference in MACE incidence was observed (log-rank p = 0.641). The cardiovascular risks associated with PD-1 inhibitors and chemo-immunotherapy may not be significantly different amongst patients with lung cancer. Cardiovascular events associated with either regimen may be uncommon.