Association between chronic diseases and disability in elderly subjects with

low and high income: the Leiden 85-plus Study

Bootsma et al European J of Public Health 2005

JM Feron

Journal Club 30.6.2006

Known association between low income and :

• Higher prevalence of chronic diseases

• More disabilities

• Shorter life expectancy

• Diseases presented at later and more severe stage

• Less access to therapeutic interventions

But what about the oldest old ?

3 hypotheses: in elderly with low income

1. Higher prevalence of disabilities in ADL

2. Higher prevalence of chronic diseases

3. Stronger association between chronic diseases and disabilities

Method

• Income: net amount for each source of income; categorisation in 2 strata around the median

• Disability: Groningen Activity Restriction Scale

• Chronic diseases: semi structured interviews with carers + medical files + data on medications + ECG

Data analysismostly by odds ratios with 95% CI

M+E+ X M-E-

OR = -----------------------

M+E- X M-E+

Results

1. Two-fold increased risk of disabilities in low income group OR 2,2 (95% CI 1,4-3,5)

First hypothese confirmed

Results

2. Prevalence of various chronic diseases equal in both groups, exept for dementia and multi morbidity

Second hypothese false

Results

3. In both strata of income, stroke, Parkinson’s disease and dementia strongly associated with disability

Third hypothese false

Results : dementia

• Higher prevalence in low income group (14% versus 6%)

• And stronger association between dementia and disability in high income group

(OR 22.7 versus 6.4)

High income people better hide their incompetence and thus are diagnosed later.

Results: myocardial infarct

Prevalence of undiagnosed myocardial infarct higher in low income group

16% versus 10 % (P = 0.05)

Discussion:in elderly with low income

1. Higher prevalence of disabilities in ADL Yes

2. Higher prevalence of chronic diseases No, but…

3. Stronger association between chronic diseases and disabilities

No So what ?