[Disability-free life expectancy among 60-year-olds in Denmark]

Life expectancy can be expressed as average expected lifetime in different health states. The purpose of the study was to estimate disability-free life expectancy, i.e. average lifetime without disabilities, in Denmark and in the counties of Denmark and evaluate the relation between life expectancy and the proportion of disability-free life expectancy.

Prevalence rates of disability (in terms of walking, walking on stairs, carrying 5 kg, reading, hearing and speaking) derived from the Danish Health Interview Survey 2000 were combined with life-table data and disability-free life expectancy was calculated by Sullivan's method.

In 2000 expected lifetime of 60-year-old men and women was 18.8 years and 22.0 years respectively and disability-free life expectancy was 14.7 years for both sexes corresponding to 78.4% and 66.6% of the remaining lifetime for men and women respectively. Differences in disability-free life expectancy between counties ranged from zero to three years. In counties with the highest life expectancy among women they tended to have a higher proportion of life years with disabilities, but there was no correlation between life expectancy and the proportion of disability-free life expectancy for men.

The results may illustrate theories about the relation between increased lifetime and quality of life in terms of health. Increased total lifetime for women prolongs the proportion of expected lifetime with disability ("expansion of morbidity"), whereas for men no correlation was found ("dynamic equilibrium").