EOAD Tied to Distinct Comorbidities, High Healthcare Use

TOPLINEIndividuals diagnosed with early-onset Alzheimer's disease (EOAD) had a significantly higher prevalence of vertigo, depression, headache, delirium, brain injuries, thyroid disorders, alcohol-related disorders, epilepsy, stroke, and otorhinolaryngologic diseases during the 1-5 years before diagnosis than matched control individuals, a study showed. Healthcare service use also increased markedly in the year prior to and the year of EOAD diagnosis.METHODOLOGYIn a population-based case-control study, researchers included 407 patients diagnosed with EOAD (defined as diagnosis at the age of ≤ 65 years) at two university hospitals in Finland between 2010 and 2021 and 4035 age- and sex-matched control individuals who lived in the same regions and had no progressive neurodegenerative disease. The mean age at diagnosis was 60.6 years in the EOAD group, and 58.5% of the participants were women in both groups.All cases were evaluated using structural MRI and comprehensive neuropsychological assessment. Cerebrospinal fluid biomarkers of Alzheimer's disease were analyzed or amyloid PET was performed when clinically indicated.Data on prior diagnoses and healthcare visits were obtained from nationwide health registers. Diagnostic codes were grouped into 23 predefined categories and analyzed across three intervals, namely 1-5 years, 6-10 years, and 11-15 years before EOAD diagnosis.Researchers also examined the number of healthcare service visits in the 15 years prior to EOAD diagnosis.TAKEAWAYIn the 1-5 years before EOAD diagnosis, the prevalence of vertigo (5.9% vs 2.1%), depression (5.7% vs 2.3%), headache (4.9% vs 1.6%), and delirium (1.5% vs 0.1%; all false discovery rate-adjusted P < .001) was significantly higher among patients with EOAD than among control individuals. Patients had more healthcare visits than control individuals in the year before diagnosis (mean, 3.3 vs 1.9; P < .001) and the year of diagnosis (mean, 6.3 vs 2.0; P < .001).Brain injuries (2.9% vs 0.9%; P = .002), thyroid disorders (2.5% vs 0.8%; P = .008), alcohol-related disorders (3.4% vs 1.4%; P = .009), epilepsy (2.2% vs 0.7%; P = .009), stroke (4.4% vs 2.0%; P = .008), and otorhinolaryngologic diseases (5.2% vs 2.9%; P = .027) were also significantly more prevalent among patients with EOAD than among control individuals 1-5 years before diagnosis.In the 6-10 years before diagnosis, only the prevalence of otorhinolaryngologic diseases (4.7% vs 2.1%; P = .036) differed significantly between the groups. No significant differences in the prevalence of any of the examined comorbidities were observed between the groups 11-15 years before EOAD diagnosis. Traditional cardiovascular risk factors, including hypertension and dyslipidemia, did not differ significantly between patients with EOAD and control individuals across all prediagnostic time intervals.IN PRACTICE"EOAD is preceded by recognizable patterns of morbidity and increased health-care use, which may support earlier detection," the authors wrote.SOURCEThe study was led by Laura Leppänen, Research Unit of Clinical Medicine, Neurology, University of Oulu, Oulu, Finland. It was published online on October 8 in Alzheimer's & Dementia.LIMITATIONSAs the study was observational, causal links could not be established and residual confounding was possible. Age at diagnosis, not symptom onset, was used to define EOAD. The researchers could not verify register diagnoses independently, so misclassification or missed entries were possible. The registers also lacked data on disease severity, functional status, and intensity of care. Additional limitations included a potential survivor bias and limited generalizability beyond Finland's health system.DISCLOSURESThe study is part of the DEGE-RWD project, which was funded by Roche Oy. This study was also funded by The Finnish Medical Foundation, Finnish Alzheimer's Disease Research Society, Finnish Brain Foundation, The Swedish Dementia Foundation, The Foundation for Geriatric Diseases at Karolinska Institutet, Uulo Arhio Foundation, The Research Council of Finland, Wihuri Foundation, Jane and Aatos Erkko Foundation, The State Research Funding, The Finnish Cultural Foundation, Päivikki & Sakari Sohlberg Foundation, and Sigrid Jusélius Foundation. Disclosure information for the study investigators is available in the original study publication.This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.