Research article

Lewy bodies and neuronal loss in subcortical areas and disability in non-demented older people: a population based neuropathological cohort study

M Byford¹ , C Brayne¹ , I McKeith² , M Chatfield¹ , PG Ince³ , FE Matthews⁴ and MRC CFAS Neuropathology group

¹  Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK

²  Institute for Ageing and Health, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne UK

³  Academic Unit of Pathology, University of Sheffield Medical School, Sheffield UK

⁴  MRC Biostatistics Unit, Cambridge, UK

author email corresponding author email

BMC Geriatrics 2009, 9:22doi:10.1186/1471-2318-9-22

Published:	15 June 2009

Abstract

Background

Functional disability, the loss of ability to carry out daily tasks unaided, is a major adverse outcome more common with increasing age. The potential contribution of neuropathological changes in subcortical areas of the brain associated with normal ageing may be a contributing factor to this loss of function. This study investigates the clinicopathological relationship between functional ability during life and pathological correlates identified at post mortem in an UK population of older people (66–102 years).

The aim is to examine the clinicopathological correlates of functional disability in subcortical neuronal populations of non-demented elderly individuals.

Methods

156 non-demented participants in the brain donation programme of the Medical Research Council Cognitive Function and Ageing Study (MRC-CFAS) were included in this study. Neuropathological examination was based on the CERAD protocol; pathologies of interest were amyloid plaques, neurofibrillary tangles, Lewy bodies, vascular disease and neuronal loss. Self-reported functional ability was scored according to a combined activities of daily living and instrumental activities of daily living scale.

Results

Functional disability was equally common in men and women over 65 years, and in both sexes disability was more common at older ages. Neuronal loss in several subcortical regions elevated the risk of functional disability by three-fold (95% CI 1.3–6.6). There was evidence for a relationship between Lewy bodies in the SN and functional disability.

Conclusion

Neuronal loss in subcortical regions is associated with functional disability in the older population. The causal relationships are not defined and require further investigation.