Hospital admissions by socio-economic status: does the 'inverse care law' apply to older Australians?

To investigate whether the 'inverse care law' applies to New South Wales (NSW) hospital admissions--especially to older people with high socio-economic status (SES).

Cross-sectional study analysing inequalities in public and private hospital admission rates by SES, defined in terms of age, sex and family income/size at the small geographic area level.

Admissions to NSW public and private hospitals in 1999-2000 (1.8 million admissions against a NSW population of 6.4 million).

Inequalities in hospitalisation rates were expressed as rate ratios across the most and least disadvantaged 20% of the NSW population.

Public hospital admission rates for people aged 0-60 years were 24-35% higher for the most disadvantaged 20% of the NSW population than for the least disadvantaged 20%. For 70+ year-olds the direction of this difference was reversed--being 14% lower for the most disadvantaged 20% of the population (5% higher for public patients). For private hospitals this reversal prevailed for all age groups (23-49% lower). For all hospitals it was 16% and 27% lower for 60-69 and 70+ year-olds respectively, with higher admission rates for top SES 60+ year-olds most pronounced for renal dialysis, chemotherapy, colonoscopies and other diagnostic scopes, rehabilitation and follow-up, and cataract operations.

While the 'inverse care law' did apply to 60+ year-olds, it did not apply either to younger NSW hospital users or to public patients in public hospitals.

Awareness of these SES-level differentials should result in greater equality of access to hospital services, especially by older people.