High burden of neurological disease in the older general population: results from the Canadian Longitudinal Study on Aging

Background and purpose: Our objective was to study the association between the presence of a neurological disease and the comorbidity burden as well as healthcare utilization (HCU).

Methods: Using baseline data from the Canadian Longitudinal Study on Aging (CLSA), we examined the burden of five neurological conditions. The CLSA is a population-based study of approximately 50 000 individuals, aged 45-85 years at baseline. We used multivariable Poisson regression to identify correlates of comorbidity burden and HCU.

Results: The lifetime prevalence of five neurological diseases is presented: epilepsy, Parkinson's disease/parkinsonism, stroke/transient ischaemic attack, multiple sclerosis and migraine. We found the somatic and psychiatric comorbidity burden to be higher in those individuals with a neurological disease (an 18-45% mean increase in the number of chronic conditions) as compared with the comparison group without a neurological disease, except for Parkinson's disease/parkinsonism. The presence of a neurological disease was associated with only a modest increase in the probability of visiting a general practitioner but was associated with a greatly increased probability of visiting a medical specialist (up to 68% more likely) or an emergency department (up to 79% more likely) and an overnight hospitalization (up to 108% more likely).

Conclusions: We found striking associations between our neurological diseases and increased comorbidity burdens and HCU. These findings are important for informing public policy planning as well as driving avenues for future research. The present study established the CLSA as an important research platform for the study of neurological conditions in an aging general population.