Regional differences in disability pension and sickness absence with psychiatric diagnoses in Sweden and Norway 1980-2000. The influence of demography and access to psychiatric health care

Abstract

Background: Psychiatric diagnoses in sickness absence (SA) and disability pensions (DP) amongindividuals under 35 years and the proportion of SA and DP with psychiatric disorders have increased inseveral countries. SA and DP with psychiatric disorders show regional differences, and imply social andeconomic consequences for individuals and a high cost to employers and society.Aim: The overall purpose of this thesis was to describe regional differences in the occurrence of SA andDP with psychiatric diagnoses and to analyse whether these regional differences were associated with age,sex or access to psychiatric health care.Method: The thesis was based on four cross-sectional studies. The study base in Sweden was themunicipality of Göteborg and the county of Göteborg and Bohuslän (excluding the municipality ofGöteborg). For Norway, the study included the municipality of Oslo and the counties Östfold, Telemark,Vestfold, Aust-Agder and Vest-Agder. Sweden and Norway as a whole were used as references, and thestudied years in Sweden were 1980,1985,1990,1995, 1998 and in Norway 1988,1990,1995,2000.Aggregated data on individuals granted DP and SA were collected from the National Insurance Board inSweden and the National Insurance Administration in Norway. Data on access to psychiatric health care(staff and beds per 10 000) were collected from the Norwegian Special Health Service. Population datawere drawn from national statistics. Standardised mortality ratio (SMR), incidence rate ratio (IRR),cumulative incidence (95%confidence intervals) were used to analysed data.Results: There were regional differences in both DP and SA with psychiatric diagnoses in Sweden andNorway. These regional differences remained after controlling for age and sex. Both men and women inurban Göteborg in Sweden and men in urban Oslo showed increased risk ratios for DP with psychiatricdiagnoses compared to national data. For both sexes in certain semi-rural regions in Norway, especiallyAust-Agder and Vest-Agder, increased risks were also found. The regional differences in DP withpsychiatric diagnoses were found in all age groups in four regions, except for the oldest age groups.Access to psychiatric health care was associated with DP with psychiatric diagnoses in certain regions butdid not explain the regional differences. Physicians, psychologists and beds were positively associated withDP rates. The cumulative incidence of DP with psychiatric diagnoses increased in the youngest age groupsduring the period of study and the cumulative incidence of SA with psychiatric diagnoses was highest andalso showed the highest increase among women in urban Oslo.Conclusion: The regional differences in SA and DP with psychiatric diagnoses could not be explained bydifferences in the age and sex composition of the populations in the different regions or by regionaldifferences in access to psychiatric health care. Future studies need to focus on the distribution of accessto psychiatric and vocational rehabilitation, to possible differences in treatment and the influence of locallabour markets. There is also a need for more gender and diagnosis specific research on SA and DP.