Mental Health and Environmental Factors in Adults: A Population-Based Network Analysis

Few studies have assessed the multifactorial nature of environmental influences on population mental health. In this large-scale, population-based study of adults, we applied network analysis to study the relationship between environmental factors and symptoms of depression, anxiety, and well-being. We estimated networks with overall mental health nodes and individual symptoms to assess both broad and fine-grained associations between environmental factors and mental health. Finally, we conducted an out-of-sample replication in an independent large-scale sample to assess the robustness of our results. Across 31,000 adults randomly sampled from the Norwegian population, we identified associations between numerous environmental characteristics and mental health. Recent discrimination and unsupportive social environments were strongly associated with lower population well-being and higher levels of mental illness symptoms, respectively. The most strongly connected variables in the networks were environmental factors, including perceived problems with crime, violence, or vandalism in the residential area, worrying about violence or threats when outside, and problems with noise or contamination at home. Substantial variation in population mental health was explained by environmental factors included in the networks. Replicability of the results was excellent and suggestive of strong robustness of the results across samples. Our findings are indicative of the importance of environmental factors, such as the social environment, housing satisfaction, and residential area characteristics, for multiple aspects of population mental health. We identify several environmental factors that represent potentially useful targets for future studies and public health efforts seeking to improve mental health in the general population.