Cancer Risk in Pulmonary Hypertension Patients

Henrik Toft Sørensen,1 Nils Skajaa,1 Frederikus Albertus Klok,2 Kristina Laugesen,1 Dóra Körmendiné Farkas1 1Department of Clinical Epidemiology, Aarhus University Hospital and Aarhus University, Aarhus N, DK-8200, Denmark; 2Department of Medicine - Thrombosis and Hemostasis, Leiden University Medical Center, Leiden, the NetherlandsCorrespondence: Henrik Toft Sørensen, Department of Clinical Epidemiology, Aarhus University, Olof Palmes Allé 43-45, Aarhus N, DK-8200, Denmark, Email hts@clin.au.dkBackground: Strong evidence indicates that venous thromboembolism is a presenting symptom of cancer. Cancer is a known cause of pulmonary hypertension; however, it remains unknown whether pulmonary hypertension is a marker of occult cancer. We examined the association between a pulmonary hypertension diagnosis and cancer risk in a cohort study using population-based data from the Danish health system.Patients and Methods: Using Danish nationwide registries, we identified 6335 patients with a pulmonary hypertension diagnosis and without a previous cancer diagnosis between 1995 and 2017. We computed the age-, sex-, and calendar year-standardized incidence ratio (SIR) as the ratio of observed to expected number of cancers using national incidence rates as the reference. We performed a subgroup analysis among patients with chronic thromboembolic pulmonary hypertension in the period in which a specific ICD-10 code was available (2006– 2017).Results: We identified 212 cancers within the first year of follow-up and 796 cancers thereafter. The one-year risk of cancer was 3.3% and the one-year SIR was 1.96 (95% confidence interval [CI]: 1.70– 2.23). In the second and subsequent years, the SIR remained elevated (SIR: 1.15 [95% CI: 1.08– 1.24]). In patients with chronic thromboembolic pulmonary hypertension, the one-year SIR was 1.41 (95% CI: 0.82– 2.25).Conclusion: Cancer risk was clearly higher in patients with pulmonary hypertension compared with the general population. The association was particularly strong in the first year of follow-up, but remained elevated thereafter. However, absolute risks were low, limiting the clinical relevance of pursuing early cancer detection in these patients.Keywords: pulmonary hypertension, chronic thromboembolic pulmonary hypertension, venous thrombosis, pulmonary embolism, cancer, cohort