TY - JOUR
T1 - Geographical variation in treated psychotic and other mental disorders in Finland by region and urbanicity
AU - Suokas, Kimmo
AU - Kurkela, Olli
AU - Nevalainen, Jaakko
AU - Suvisaari, Jaana
AU - Hakulinen, Christian
AU - Kampman, Olli
AU - Pirkola, Sami
N1 - Funding Information:
This study was funded by the Jalmari and Rauha Ahokas Foundation, European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant agreement No. 101040247 to CH), and the Finnish Psychiatric Association. The funding sources had no role in study design, data collection, analysis, interpretation, writing, or submission.
Funding Information:
Open access funding provided by Tampere University including Tampere University Hospital, Tampere University of Applied Sciences (TUNI). This study was funded by the Jalmari and Rauha Ahokas Foundation, European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant agreement No. 101040247 to CH), and the Finnish Psychiatric Association. The funding sources had no role in study design, data collection, analysis, interpretation, writing, or submission.
Publisher Copyright:
© 2023, The Author(s).
PY - 2023/6
Y1 - 2023/6
N2 - Purpose: In Finland, prevalence of schizophrenia is higher in the eastern and northern regions and co-occurs with the distribution of schizophrenia polygenic risk scores. Both genetic and environmental factors have been hypothesized to contribute to this variation. We aimed to examine the prevalence of psychotic and other mental disorders by region and degree of urbanicity, and the impacts of socio-economic adjustments on these associations. Methods: Nationwide population registers from 2011 to 2017 and healthcare registers from 1975 to 2017. We used 19 administrative and three aggregate regions based on the distribution of schizophrenia polygenic risk scores, and a seven-level urban–rural classification. Prevalence ratios (PRs) were calculated by Poisson regression models and adjusted for gender, age, and calendar year (basic adjustments), and Finnish origin, residential history, urbanicity, household income, economic activity, and physical comorbidity (additional adjustments) on an individual level. Average marginal effects were used to visualize interaction effects between region and urbanicity. Results: A total of 5,898,180 individuals were observed. All mental disorders were slightly more prevalent (PR 1.03 [95% CI, 1.02–1.03]), and psychotic disorders (1.11 [1.10–1.12]) and schizophrenia (1.19 [1.17–1.21]) considerably more prevalent in eastern and northern than in western coastal regions. After the additional adjustments, however, the PRs were 0.95 (0.95–0.96), 1.00 (0.99–1.01), and 1.03 (1.02–1.04), respectively. Urban residence was associated with increased prevalence of psychotic disorders across all regions (adjusted PR 1.21 [1.20–1.22]). Conclusion: After adjusting for socioeconomic and sociodemographic factors, the within-country distribution of mental disorders no longer followed the traditional east–west gradient. Urban–rural differences, on the other hand, persisted after the adjustments.
AB - Purpose: In Finland, prevalence of schizophrenia is higher in the eastern and northern regions and co-occurs with the distribution of schizophrenia polygenic risk scores. Both genetic and environmental factors have been hypothesized to contribute to this variation. We aimed to examine the prevalence of psychotic and other mental disorders by region and degree of urbanicity, and the impacts of socio-economic adjustments on these associations. Methods: Nationwide population registers from 2011 to 2017 and healthcare registers from 1975 to 2017. We used 19 administrative and three aggregate regions based on the distribution of schizophrenia polygenic risk scores, and a seven-level urban–rural classification. Prevalence ratios (PRs) were calculated by Poisson regression models and adjusted for gender, age, and calendar year (basic adjustments), and Finnish origin, residential history, urbanicity, household income, economic activity, and physical comorbidity (additional adjustments) on an individual level. Average marginal effects were used to visualize interaction effects between region and urbanicity. Results: A total of 5,898,180 individuals were observed. All mental disorders were slightly more prevalent (PR 1.03 [95% CI, 1.02–1.03]), and psychotic disorders (1.11 [1.10–1.12]) and schizophrenia (1.19 [1.17–1.21]) considerably more prevalent in eastern and northern than in western coastal regions. After the additional adjustments, however, the PRs were 0.95 (0.95–0.96), 1.00 (0.99–1.01), and 1.03 (1.02–1.04), respectively. Urban residence was associated with increased prevalence of psychotic disorders across all regions (adjusted PR 1.21 [1.20–1.22]). Conclusion: After adjusting for socioeconomic and sociodemographic factors, the within-country distribution of mental disorders no longer followed the traditional east–west gradient. Urban–rural differences, on the other hand, persisted after the adjustments.
KW - Geographical
KW - Mental disorders
KW - Prevalence
KW - Schizophrenia
KW - Social determinants
KW - Urbanicity
U2 - 10.1007/s00127-023-02516-x
DO - 10.1007/s00127-023-02516-x
M3 - Article
AN - SCOPUS:85161672543
SN - 0933-7954
JO - SOCIAL PSYCHIATRY AND PSYCHIATRIC EPIDEMIOLOGY
JF - SOCIAL PSYCHIATRY AND PSYCHIATRIC EPIDEMIOLOGY
ER -
