AbstractsEconomics

Dementia and use of drugs : economic modelling and population-based studies

by Anders Sköldunger




Institution: Karolinska Institute
Department:
Year: 2015
Record ID: 1334843
Full text PDF: http://hdl.handle.net/10616/44463


Abstract

The overall aim of this thesis was to investigate epidemiological and health economic aspects of dementia and drug use in older people, through economic modelling and analyses of population-based studies. The major findings from the separate studies are summarized below. Study I We aimed to investigate whether dementia was associated with higher drug costs in 4,108 participants aged ≥ 60 years from the Swedish National Study on Aging and Care in Kungsholmen and Nordanstig (SNAC-K and SNAC-N). Overall, the average crude cost of drug use was 6,147 SEK per year for people with dementia and 3,810 SEK per year for people without dementia. The cost of nervous system drugs was more than five times higher in persons with dementia than without. However, the higher crude costs for drug use in people with dementia were confounded by comorbidities and residential setting. In fact, the strongest drug cost driver was comorbidity followed by residential setting. Study II We aimed to investigate inappropriate drug use (IDU) and risk of hospitalizations and mortality in older persons and in persons with dementia and to also estimate the costs of IDU-related hospitalizations. In this study, based on data from SNAC-K and SNAC-N, the National Patient Register and the Cause of Death Register, we used logistic and Cox regression models to analyse associations between IDU, hospitalizations and mortality in the whole study population and in the subpopulation of persons with dementia. We found a higher risk of hospitalization (adjusted OR=1.46; 95% CI 1.18-1.81) and mortality (adjusted HR=1.15; 95% CI 1.01-1.31) in the whole study population and with hospitalization (adjusted OR=1.88; 95% CI 1.03-3.43) in the subpopulation of persons with dementia, after adjustment for confounding factors. There was also a tendency for higher costs for hospitalizations with IDU than without IDU, although not statistically significant. Study III We aimed to describe the costs of an incident cohort of persons with dementia through simulation modelling. With input from epidemiological data, the Markov model estimated approximately 24,000 incident cases of dementia in Sweden in 2005. The incident cohort was run in the model for ten cycles of one year each. State specific costs were used and defined by the Clinical Dementia Rating scale. Results of the simulation showed that the total costs of the cohort were 27.7 billion SEK. The average annual cost of one person with dementia was 269,558 SEK. The severe state of dementia accounted for the largest proportion of costs for incident dementia cases. Costs of drugs in dementia only accounted for about 2% of the costs in the model. The main cost driver was institutional care, even for mild dementia. Study IV We aimed to introduce a hypothetical economic model of a disease modifying treatment (DMT) for Alzheimer’s disease (AD). We created a Markov model built on Swedish conditions with two arms; one representing the hypothetical treatment and the other arm representing no treatment. States and progression…