Suicide and Types of Agriculture: A Time-Series Analysis in Japan

Spatial statistical analysis of regional disparities in suicide among policy units in Japan: Using the Bayesian hierarchical model

Suicide prevention is a crucial policy issue in Japan to be addressed nationally. Nevertheless, if there are regional differences in suicide, even in adjacent sub-regions, measures may need to be taken at the sub-regional level. Previous studies have not compared regional differences in suicide based on the size of policy units, such as prefectures, secondary medical areas, and municipalities. This study used the number of suicides from open data for 10 years from 2009 to 2018 to obtain shrinkage estimates of the standardized mortality ratio (SMR) using the Bayesian hierarchical model. We visualized and compared the regional disparities in suicide for each policy unit. For each gender and policy unit, adjacent regions had similar clusters of SMRs and positive spatial autocorrelation of global Moran's I (p < 0.001 for each). Comparisons between each policy unit showed that even if the SMR was low for the prefectural units, there were regions with high SMRs in municipalities and secondary medical areas, and vice versa. It was found that assessing suicide solely on a prefecture-by-prefecture basis may overlook regional disparities in suicide. This research emphasizes the need to establish suicide indicators at the secondary medical or municipal level and execute individual suicide prevention interventions in neighboring communities. Prefectures can also play a role in developing collaborative cooperation between neighboring regions by acting as actors.

Relationships between management factors in dairy production systems and mental health of farm managers in Japan

To facilitate sustainable dairy farming, it is essential to assess and support the mental health of dairy farm workers, which is affected more than that of workers in other industries, as indicated by the relatively few studies to date. In addition, the limited investigations on mental health in dairy workers minimize the opportunities to suggest practical approaches of improvement of their mental health. Therefore, further data acquisition and analysis is required. In the present study, we undertook quantitative surveys on 17 management factors and administered a mental health questionnaire to 81 dairy farm managers (80 male, 1 female) in Hokkaido, northern Japan. The management factors were categorized into 3 groups: production input, production output, and facility indicator; mental health was evaluated based on the Center for Epidemiologic Studies Depression Scale (CES-D). Principal component analysis assigned the factors into 2 groups: intensiveness factors of dairy production systems (PC1: livestock care cost, fat- and protein-corrected milk, stocking density, medical consultation fee per unit time per animal unit, nonfamily wages, fertilizer and pesticide expenses, and net agricultural income ratio) and basic dairy management factors (PC2: net agricultural income ratio, quantity of concentrate feed, and milk quality variable). The depression symptoms of dairy farm managers were not significantly associated with PC1 and milking methods; however, they were significantly negatively associated with PC2, which integrated 3 management factors, including factors related to finances, feeding, and milk quality. According to the findings of the present study, the efforts needed for stable economic farm management, adequate feed supply, and milk quality maintenance may increase the depression levels of dairy farm managers and negatively affect their mental health. These findings could be the basis for future studies on the relationship between the mental health of farm managers and sustainable dairy farm management and production.

Suicide mortality rates in farm-related occupations and the agriculture industry in the United States

BACKGROUND

Studies suggest that agricultural workers and rural residents may have an elevated suicide risk. However, suicide is relatively rare, and rural and farming populations have significantly declined, limiting their representation in national surveys. Many studies have inadequate samples for meaningful analysis.

METHODS

We pooled 29 years of data from the Mortality-Linked National Health Interview Survey, 1986-2014, then measured suicide mortality in groups including agriculture workers, and variation in suicide across rural and urban areas. Exposure variables indicated whether participants worked in a farm-related occupation or industry, or lived in a rural area. We used survey-weighted Poisson regression to estimate suicide mortality rates and rate ratios.

RESULTS

Age-adjusted suicide mortality rate per 100,000 was: 22.3 for farmers and farm managers; 21.6 for farmworkers; 28.7 in farming, forestry, and fishing; 15.3 across all other occupations; 16.1 among rural residents. Among farmworkers, age-adjusted rates were 28.3 in rural areas, 17.1 in urban areas (not significantly different). The age-adjusted suicide mortality rate ratio (RR) comparing workers in the agriculture, forestry, and fishery industries to those in all other industries was 1.34 (95% confidence interval, [CI]: 1.05-1.72) (not statistically significant after further adjustment for demographic characteristics). Age-adjusted results were consistent with a higher suicide risk for workers in forestry and fishing than in all other occupations (RR: 1.88, 95% CI: 0.79-4.46).

CONCLUSION

Workers in agriculture, forestry, and fishing may have an elevated suicide risk. National surveys should consider oversampling of rural residents, who have increased morbidity and mortality risks.

Factors Associated with Suicidal Behavior in Farmers: A Systematic Review

This review aimed to investigate the factors associated with suicidal behavior in farmers in the scientific literature. Two researchers participated independently in searching databases, specifically PubMed/MEDLINE, LILACS, Web of Science, Scopus, PsycINFO, and SciELO. Only observational studies were included. The quality of the selected studies was assessed with a critical assessment checklist for cross-sectional analytical and case-control studies, prepared by the Joanna Briggs Institute. Data related to the publication were collected (author and year; city/country); methodological design; sample/population (gender; average age), outcome, measuring instrument and factors associated with suicidal behavior. A total of 14 studies were included in the systematic review, and factors associated with farmers' behavior in mental health (depression), seasonal impacts (drought), and work exposures (herbicides and insecticides) were identified. However, heterogeneity was found in terms of the method, measurement of suicidal behavior, and associated factors, which indicates the need for further studies.

Neighborhood farm density, types of agriculture, and depressive symptoms among older farmers: a cross-sectional study

BACKGROUND

Farmers may have an increased risk for poor mental health. In connection with this, factors specific to the neighborhood environment such as farm density and the type of agriculture, might be important for mental wellbeing. In this study we aimed to clarify the cross-level interaction on depressive symptoms between farm density at the neighborhood level by type of agriculture and the longest occupation of individuals (farmer or non-farmer).

METHODS

Data came from the 2016 wave of the Japan Gerontological Evaluation Study (JAGES) that were linked to governmental agricultural data. Information was analyzed from 147,549 respondents aged 65 years or older, residing in 1024 neighborhoods in 39 municipalities. We calculated farm (crop or animal husbandry) density at the neighborhood level, dividing the number of agricultural management entities by the population. Three-level (individual, neighborhood, and municipality) Poisson regression analysis was used to calculate the prevalence rate ratios of depressive symptoms.

RESULTS

The prevalence of depressive symptoms was higher among individuals whose longest occupation was farmer compared to non-farmer. The estimated probability of depressive symptoms by a cross-level interaction analysis showed that among farmers of both genders, those who were residing in neighborhoods where the farm density was low had a higher prevalence of depressive symptoms, regardless of the type of agriculture. The slope of the relationship between depressive symptoms and animal husbandry farm density varied by occupation, with a higher prevalence of depressive symptoms observed in male farmers compared to male non-farmers.

CONCLUSIONS

The high prevalence of depressive symptoms among farmers in neighborhoods with a low farm density may reflect a scarcity of formal and informal social support in such communities. The health effects of the neighborhood environment on farmers, such as farm density, which may vary by the type of agriculture, should be further researched.