Can access to psychiatric health care explain regional differences in disability pension with psychiatric disorders?

Psychiatric disorders are a serious public health problem, especially as many psychiatric disorders begin early in life. Disability pension (DP) with psychiatric diagnoses has, since the mid 1990s, increased in several European countries and regional differences within countries have emerged. It is not clear whether these regional differences are associated with differences in access to psychiatric health care.

The aim of this study was to investigate whether regional differences in DP with psychiatric diagnoses in Norway were associated with differences in psychiatric service provision (the number of staff employed and psychiatric beds available).

The study population consisted of individuals aged 16-67 years living in Norway (n = 4,348,410) and six southern regions. Included cases were individuals who were granted a DP with a psychiatric diagnosis between 1 January and 31 December 1990, 1995 or 2000. Mental retardation was excluded. Data on cases were collected from the National Insurance Administration and data on psychiatric health care staff and beds was collected from Specialist Health Service, Statistics Norway. Regression models were used to calculate incidence rate ratios (IRR) with 95% confidence intervals (CI) using Norway as reference.

Staffing levels (per 10,000 inhabitants) did not differ substantially between the regions, with the exception of Oslo that had about 70% higher numbers of staff employed. In regression analyses controlling for numbers of psychiatric staff and beds, regional differences in DP remained. Both men and women in the semi rural regions Aust-Agder and Vest-Agder were significantly more likely to receive a DP with a psychiatric diagnosis, while the IRR for DP was reduced in Ostfold. Different psychiatric staff groups were associated with increased or decreased rates of DP. The adjusted IRR between number of psychiatric staff (man-years of staff per 10,000 inhabitants) and DP with psychiatric diagnoses were: 1.23 (1.18-1.29) for psychologists, 1.13 (1.04-1.23) for physicians, 1.03 (1.00-1.07) for nurses and 0.84 (0.80-0.88) for auxiliary nurses. Furthermore, increased numbers of beds were associated with DP with a psychiatric diagnosis (IRR 2.86 (2.03-4.05) for 100 beds/10,000 population).

Psychiatric provision (in terms of both staff and beds) was associated with the incidence of DP with psychiatric diagnoses but regional differences in provision did not explain the regional differences in DP with a psychiatric diagnosis. Future work needs to examine whether differences in case detection and case management are associated with regional differences in DP with psychiatric diagnoses.