Comorbidity patterns and the risk of injurious falls in older people with atrial fibrillation: Findings from a Swedish nation-wide population-based study

Background: Atrial fibrillation (AF) is associated with an increased fall risk, partly due to AF-related comorbidities. We investigated the impact of different comorbidity patterns on fall risk in older adults with AF. Methods: Using the Swedish National Patient Register, we identified 203,042 adults (45 % females) with AF and at least one comorbidity, aged 65 years or older, on 01/01/2017. The primary study outcome was any fall requiring medical attention. Secondary outcomes were falls with fractures, falls with hip fractures, and falls with head trauma. Comorbidity patterns were identified through latent class analysis, and their association with 3-year fall risk was tested through Cox regressions. Results: The sample mean age was 79.6 (SD: 7.9) years, and the mean number of chronic diseases was 6.6 (SD 3.2). We identified one unspecific (34.2 %) and six specific comorbidity patterns characterized by neuropsychiatric (6.6 %), eye (17.4 %), musculoskeletal (7.2 %), metabolic (15.8 %), cardiovascular (7.4 %), and complex (11.3 %) chronic conditions coexisting with AF. Older adults with AF and complex (HR=1.63, 95 %CI: 1.56-1.70), neuropsychiatric (HR=1.48, 95 %CI: 1.41-1.56), cardiovascular (HR=1.21, 95 %CI: 1.15-1.27), eye (HR=1.16, 95 %CI: 1.12-1.20), and musculoskeletal (HR=1.07, 95 %CI: 1.01-1.13) comorbidity had an increased fall risk compared to those with unspecific comorbidity. The highest risk of falls with fractures or head trauma was found in older adults displaying a complex or neuropsychiatric disease pattern, respectively. Higher estimates emerged in males and those aged <80 years. Conclusions: Evaluating comorbidity patterns in older AF patients could help stratify the risk of falls in this population and support targeted preventive interventions.