Mental health in Norwegian farmers: The HUNT Study

Abstract

Agriculture in industrialized countries has undergone major structural changes in recent decades. Farmers are exposed to a number of work-related stressors, such as high levels of work, unfavourable weather, financial difficulties, agricultural policies, and insecurities related to the future of their farms and of agriculture in general. These stressors may have an impact on the mental health of farmers, but the literature is inconclusive as to whether the mental health of farmers differs from that of people in other occupational groups. The Nord-Trøndelag Health Study (Helseundersøkelsen i Nord-Trøndelag, HUNT) is one of The world’s largest health studies to date. The HUNT Study is a total population-based study conducted in the county of Nord-Trøndelag, Norway, and consists of three cohorts: HUNT1 (1984-1986), HUNT2 (1995-1997), and HUNT3 (2006-2008). In total, more than 125,000 people have participated in the study, many of whom have had repeated measurements. We used data from all the three waves of the HUNT Study to investigate the mental health of Norwegian farmers. Paper I reports a cross-sectional study of occupationally active HUNT3 participants in the age group 19 – 66 years. We found that the levels of farmers’ anxiety symtoms were similar to those in other occupational groups. Farmers, in particular male farmers, had a higher mean level of symptoms of depression compared with other occupational groups, including other manual occupations with presumed lower socio-economic status. We also found that the difference in the mean level of depression symptoms between farmers and the occupationally active general population increased with increasing age. Paper II reports a prospective cohort study that included HUNT2 participants who were occupationally active and in the age group 19-62 years at baseline. We linked HUNT data with national registry data on disability and retirement pensions, and estimated the risk of receiving a disability pension for different occupational groups. We found that from a socioeconomic perspective farmers had an intermediate risk of being in receipt of a disability pension. We also investigated the association between symptoms of anxiety or depression in HUNT2 and the risk of receipt of a disability pension in the future. We found that symptoms of anxiety or depression at baseline were associated with a relatively similar absolute risk increase of receiving a disability pension in different occupational groups, with the possible exception of unskilled manual workers, who may have had a somewhat higher risk increase. For the research reported in Paper III, we used data from all three waves of the HUNT Study, using several different designs. In a prospective cohort study, we found that the farmers had similar odds of having symptoms of psychological distress and anxiety 11 years after the baseline occupational measurement as other manual occupational groups. Farmers had the highest prospective odds of having symptoms of depression, although the differences between farmers and other manual occupations were minor. We also used national registry data to compare the mental health of farmers with that of their siblings working in other occupations. We found that the farmers had higher odds of having symptoms of depression than their siblings in the periods 1995-1997 and 2006-2008. Regarding symptoms of anxiety, we did not find a difference between farmers and their siblings in the period 1995-1997, but there was a tendency for farmers to have higher odds of symptoms of anxiety than their siblings in the period 2006-2008. Further, we found that farmers appeared to follow the same general trends of symptoms of anxiety and depression as workers in other manual occupations, both over time and throughout their lifespan. We found that farmers, in particular men, had a high prevalence of symptoms of depression compared with other occupational groups. With the possible exception of the sibling study, there did not appear to be any differences in symptoms of anxiety between farmers and other occupational groups. Farmers appeared to follow the same general trends in mental health as other occupational groups, but the results of the sibling analysis suggested that working in agriculture may have an impact on mental health. Additionally, our results suggest that there is a need for preventive mental health efforts within the agricultural industry and in the health care system, and may be of importance for shaping future agricultural policy.