Increase in stroke risk in patients with head and neck cancer: a retrospective cohort study.

<bold>Background: </bold>This study investigated the stroke risk in patients with head and neck cancers (HNCs) using population-based data.<bold>Methods: </bold>From claims collected in the Taiwan National Health Insurance database, we identified 13,390 HNC patients with diagnosis made in 2000-2002. A reference cohort of 53,517 non-cancer individuals matched for age, gender, and stroke risk factors was used for assessing stroke risk in follow-up to 2008.<bold>Results: </bold>The overall stroke incidence was 1.44-fold higher in the HNC than in the reference cohort (11.4 vs 7.9 per 1000 person-years). Adjusted hazard ratios (HRs) were 1.54 (95% confidence interval (CI): 1.40-1.68) for ischaemic stroke and 1.36 (95% CI: 1.09-1.69) for haemorrhagic stroke. The cancer-to-reference stroke incidence rate ratio was age dependent and the highest in the age group younger than 40 years (5.45, 95% CI: 3.78-7.87) and decreased with aging. Comparing different therapeutic modalities, HNC patients receiving both radiotherapy (RT) and chemotherapy (CT) had the highest stroke risk (HR: 1.46, 95% CI: 1.22-1.74), followed in sequence by those who had CT alone, RT alone, and without therapy.<bold>Conclusion: </bold>Patients with HNC are at increased risk of developing stroke, especially in the young age group and in those who received both RT and CT. [ABSTRACT FROM AUTHOR]