Mortality in narcolepsy and other sleep clinic patients: a 25-year propensity-matched VA cohort study

Abstract

Importance Prior research shows increased mortality in patients with narcolepsy compared to the general population; overall, the evidence remains highly controversial and comparative data with general sleep clinic populations remains limited. Objective We examined mortality and healthcare utilization among patients with narcolepsy compared to a general sleep clinic (GSC) cohort in the Veterans Affairs (VA) health system. Design Retrospective cohort study. Setting Nationwide Veterans Health Administration (VHA) data from October 1999 through March 2025. Participants The study used relevant ICD-9/10 codes. We defined narcolepsy 1 (NT1) as patients with at least two NT1 ICD-9/10 codes. We constructed two propensity-matched (on age at index date, sex, race/ethnicity, and diagnosis year) comparison groups: (i) General Sleep Clinic (GSC; with no central disorders of hypersomnia ICD codes), matched 1:3 and (ii) other narcolepsy (ON) group as patients with at least two narcolepsy ICD-9/10 codes but no NT1-specific codes, matched 1:1 to NT1 group. Main outcomes and measures The primary outcome was all-cause mortality. Secondary outcomes included all-cause hospitalization and emergency department/urgent care (ED/UC) visits. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were estimated using multivariable logistic regression in the propensity score-matched cohorts, with GSC as the reference group and adjustment for age, body mass index, and Charlson Comorbidity Index. Results The cohort included 4161 NT1, 4161 ON, and 12,843 GSC participants. The mean age differed in the groups (48.0, 47.6, and 43.8 years for NT1, ON, and GSC, respectively). All-cause mortality was more frequent in NT1 and ON compared to GSC (24.7%, 29.1%, and 15.0% in NT1, ON, and GSC, respectively). Compared with GSC, aOR was higher in NT1 (aOR 1.64, 95% CI 1.47-1.82) and ON (aOR 2.40, 95% CI 2.16-2.66). In contrast, increased aOR of all-cause hospitalization was observed only in NT1 (aOR 1.13, 95% CI 1.05-1.22) compared to GSC. Conclusions and relevance Among veterans referred for sleep evaluation, adjusted OR of all-cause mortality was higher in narcolepsy patients compared to patients with other sleep disorders. The generalizability to non-VA populations remains uncertain. Future studies should identify cause-specific mortality and modifiable risk factors for prevention.