Interventions targeting built environmental factors may encourage older people to engage in favorable behaviors and decrease dementia risk, but epidemiologic evidence is limited. This study investigated the association between neighborhood food environment and dementia incidence. A 3-year follow-up (2010-2013) was conducted among participants in the Japan Gerontological Evaluation Study, a population-based cohort study of older adults aged ≥65 years. Dementia incidence for 49,511 participants was assessed through the public long-term care insurance system. Availability of food stores (defined as the number of food stores selling fruits and vegetables within 500 meters or 1 kilometer of residence) was assessed for each participant using objective (GIS-based) and subjective (participant-reported) measurements. Data were analyzed from 2017 to 2018. A total of 3,162 cases of dementia occurred during the follow-up. Compared with the highest quartile for objective availability of food stores, the hazard ratio adjusting for age and sex was 1.60 (95% CI=1.43, 1.78) for the second-lowest quartile. Compared with the highest subjective availability of food stores, the hazard ratio was 1.74 (95% CI=1.49, 2.04) for the lowest category. After successive adjustment for sociodemographic characteristics, health status, and other geographic neighborhood factors (availability of restaurants, convenience stores, and community centers), the hazard ratio remained statistically significant. Lower food store availability was associated with increased dementia incidence. Given that food shopping is a routine activity and a main motive for going out among older adults, increasing the availability of food stores may contribute to dementia prevention.

Depression in older adults is a public health challenge. We aimed to clarify the relationship between depression in older adults and three types of neighborhood greenspaces: trees, grasslands, and fields. We utilized data from the Japan Gerontological Evaluation Study (JAGES) performed in 2016. Multilevel logistic regression analysis was used for non-stratified and stratified analyses for the urban–rural regions. The target population comprised 126,878 older adults (age ≥ 65 years) who responded to the depression questions and were living in 881 neighborhoods in Japan. Depression was diagnosed based on a Geriatric Depression Scale score ≥5, and 20.4% of the study population had depression. In the pre-stratification analysis, areas with more greenspaces revealed lower odds of depression (odds ratio (OR) 0.95, 95% confidence interval (CI) 0.85–0.95). In urban areas, more trees correlated with lower odds of depression (OR 0.94, 95% CI 0.89–1.00). In rural areas, moderate amounts of grassland were associated with lower odds of depression compared to areas with fewer grasslands (OR 0.91, 95% CI 0.83–1.00). We found that urban areas with higher tree density and rural areas with moderate amounts of grassland were associated with lower odds of depression.

Background: With the aim to prevent sick building syndrome and worsening of allergic symptoms, primarily resulting from the indoor environment, the relationships among people’s residential environment in recent years, their lifestyle habits, their awareness, and their symptoms were investigated using an online survey. Methods: In the survey, respondents experiencing symptoms specific to sick building syndrome, although they were not diagnosed with sick building syndrome, were categorized in the pre-sick building syndrome group. The relationships among individual characteristics, residential environment, and individual awareness were analyzed. Results: Results showed that the prevalence of pre-sick building syndrome was high among young (aged 20–29 years) population of both sexes. In addition, “condensation,” “moisture,” “musty odors” in the house, and the “use of deodorant and fragrance” were all significantly associated with pre-sick building syndrome. Conversely, there was no significant association with recently built “wooden” houses that are highly airtight and have thermal insulation. Conclusions: Efficient “ventilation” plans and “ventilation” improvement and air conditioning systems to prevent mold and condensation in rooms are necessary to maintain a good, indoor environment that is beneficial for health. Efforts should also be made to encourage individuals to regularly clean and effectively ventilate their homes.