Incidence and survival of haemophagocytic lymphohistiocytosis: A population‐based cohort study from England

West, Joe; Card, Tim R.; Bishton, Mark J.; Lanyon, Peter; Ban, Lu; Bythell, Mary; Elliss-Brookes, Lucy; Manson, Jessica J.; Nanduri, Vasanta; Rankin, Judith; Tattersall, Rachel S.; Crooks, Colin J.

Abstract

Background: Haemophagocytic lymphohistiocytosis (HLH) is a rare hyper-inflammatory condition with poor outcomes. Objectives: Few population-based estimates of the incidence and survival in adults exist. We aimed to provide these data for England. Methods: We used population-based linked data from primary care, secondary care, cancer registries and mortality databases in England to identify people diagnosed with HLH between 1 January 2000 and 31 December 2016. We calculated annual incidence rates by age and sex, modelled change in incidence over time with Poisson regression, calculated overall 1-year survival using Kaplan–Meier methods and estimated adjusted hazard ratios (HRs) of death using a Cox proportional hazards model. Results: We identified 214 patients with HLH. The reported age and sex-adjusted incidence increased twofold over the period, from around one to around two per million. Incidence was highest in those below 1 year (14.6 per million) and ≥75 years (2.2 per million), and lowest in those aged 15–44 years (0.8 per million). One-year survival varied by age and sex from 77% (95% confidence interval [CI] 63%–86%) in those <15 years to 30% (95% CI 14%–49%) in those ≥75. In patients with haematological cancer, the adjusted HR for death was 2.60 (95% CI 1.45–4.66) compared to patients with no malignant or rheumatological disease. Conclusion: The incidence of HLH diagnosis in England has increased between 2000 and 2016 and occurs in all ages with varying underlying diseases. One-year survival varies substantially, being particularly poor in those aged over 75 years and those with haematological malignancy.

• Journal Article Type: Article
• Acceptance Date: Dec 7, 2021
• Online Publication Date: Dec 22, 2021
• Publication Date: Apr 1, 2022
• Deposit Date: Nov 23, 2021
• Publicly Available Date: Dec 23, 2022
• Journal: Journal of Internal Medicine
• Print ISSN: 0954-6820
• Electronic ISSN: 1365-2796
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 291
• Issue: 4
• Pages: 493-504
• DOI: https://doi.org/10.1111/joim.13432
• Keywords: HLH; epidemiology; incidence; survival
• Public URL: https://nottingham-repository.worktribe.com/output/6785089
• Publisher URL: https://onlinelibrary.wiley.com/doi/10.1111/joim.13432
• Additional Information: Published: 2021-12-22