The enduring effect of education-socioeconomic differences in disability trajectories from age 85 years in the Newcastle 85+ Study.
OBJECTIVE
Little is known about disability progression in very old age despite this being vital for care planning. We investigate whether distinct trajectories of disability are evident from age 85 to 90 and their association with socio-economic status (SES).


METHODS
The Newcastle 85+ Study recruited people born in 1921 through participating general practices in Newcastle and North Tyneside. Participants underwent a health assessment (HA) at baseline, 18, 36 and 60 months and a GP record review (GPRR) at baseline, 36 and 60 months. Disability was measured via difficulty in 17 Activities of Daily Living. Trajectory identification was assessed by gender stratified, mortality adjusted, group-based trajectory modelling (GBTM) and the impact of life-course SES (level of education; occupational class; deprivation) on trajectory membership evaluated (adjusting for confounding variables).


RESULTS
851 participants agreed to HA and GPRR, 840 (98.7%) with complete disability data. Four distinct trajectories were evident for both sexes. A disability-free trajectory between age 85 and 90 was identified in men only (9% of the sample). The most disabled trajectories had severe disability at age 85 progressing to profound disability by age 90. After adjusting for confounders education remained significant; men and women with most education being less likely to be in the most disabled trajectory (Men: OR=0.80, 95% CI 0.65-0.98; women: OR=0.59, 95% CI 0.42-0.83).


CONCLUSIONS
Distinct disability trajectories are evident in the very old and these are influenced by education, suggesting SES disadvantages cumulate throughout the life-course to create health and mortality inequalities later.
Institute of Health and Society, Newcastle University, Baddiley-Clark Building, Richardson Road, Newcastle upon Tyne NE2 4AX, United Kingdom. Electronic address: andrew.kingston@ncl.ac.uk.
Andrew
A
Kingston
Institute of Health and Society, Newcastle University, Baddiley-Clark Building, Richardson Road, Newcastle upon Tyne NE2 4AX, United Kingdom.
Karen
K
Davies
Institute of Health and Society, Newcastle University, Baddiley-Clark Building, Richardson Road, Newcastle upon Tyne NE2 4AX, United Kingdom.
Joanna
J
Collerton
Institute of Health and Society, Newcastle University, Baddiley-Clark Building, Richardson Road, Newcastle upon Tyne NE2 4AX, United Kingdom.
Louise
L
Robinson
Institute of Health and Society, Newcastle University, Baddiley-Clark Building, Richardson Road, Newcastle upon Tyne NE2 4AX, United Kingdom.
Rachel
R
Duncan
Insititue of Cellular Medicine, William Leech Building, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom.
Thomas B L
TB
Kirkwood
Institute of Health and Society, Newcastle University, Baddiley-Clark Building, Richardson Road, Newcastle upon Tyne NE2 4AX, United Kingdom. Electronic address: carol.jagger@ncl.ac.uk.
Carol
C
Jagger
D000203:Activities of Daily Living; D000369:Aged, 80 and over; D006233:Persons with Disabilities; D018450:Disease Progression; D004522:Educational Status; D005260:Female; D015577:Geriatric Assessment; D006801:Humans; D008297:Male; D012923:Social Class
Disability; Education; Longitudinal studies; Newcastle 85+ Study; The very old; Trajectories