[Increase in hospital services utilization by persons aged 55 years or older: population ageing and response of the health system].

Objectives: To examine changes in hospital service utilization between 1985 and 1994 in Spain and Andalucía and to estimate the proportion of change due to population ageing.
Methods: The increase in hospitalization rates between 1985 and 1994 was calculated. Expected hospital discharges in 1994, were calculated by multiplying hospital discharge rates in 1985 by the population in 1994 for each age group.
Results: Between 1985 and 1994 hospitalization rates increased among persons aged 55 years old order. The increase ranged from 20.01% (55-64 years old) to 52% (more than 75 years old). The percentage of this increase due to population ageing was slight (range: 2.8 to 14.8%).
Conclusions: The increase in hospitalization rates among persons aged 55 years old or older is only partially explained by population ageing, which can be attributed to supply and demand of services.