Three-year effects of neighborhood social network intervention on mental and physical health of older adults

OBJECTIVES

Although neighborhood is considered to be a crucial source of social network to promote health among older adults, current findings are mostly derived from observational study designs. This study examined whether participations in event-based community programs could increase neighborhood social network and whether such increase could lead to desirable changes in mental and physical health among older adults.

METHOD

This study employed quasi-experimental design. A baseline questionnaire survey was sent to residents of Tsurukabuto community aged 60 years or more (n = 1769); 1,068 responded. Community events were implemented approximately once a month for three years. Then, a three-year follow-up survey questionnaire was sent to the respondents of the baseline survey. The total number of respondents in the latter survey was 662; of the total, 173 participated in the intervention. Strong and weak ties with neighbors, mental well-being (Ikigai-9), health-related quality of life (HRQOL), and instrumental activity of daily living (IADL) were measured in the surveys.

RESULTS

The path analysis revealed that intervention participation was significantly associated with changes in strong ties (standardized path coefficient = 0.12) and changes in strong ties were associated with those in Ikigai-9 scores (standardized path coefficient = 0.15). The total and indirect effects of intervention participation on Ikigai-9 scores were significant. Significant intervention effects were not observed for HRQOL and IADL scores.

CONCLUSION

This study found that participation in our event-based intervention could indirectly and positively influence older adults' mental well-being through their strong ties with their neighbors.

Effects of delaying post-hatch feeding on lipid peroxidation and antioxidant enzyme mRNA expression in the pectoralis major muscle of newly hatched chicks

Excessive lipid peroxidation negatively affects the physiological response and meat quality of chickens. Delaying post-hatch feeding was previously found to increase lipid peroxidation in the skeletal muscle of finishing broiler chickens. The aims of this study were to investigate the effects of delayed post-hatch feeding on lipid peroxidation and the mRNA expressions of antioxidant enzymes in the pectoralis major muscle of broiler chicks during the post-hatching period. Newly hatched chicks either had immediate free access to feed (freely-fed chicks) or had no access to feed from 0 to 2 days old (delayed-fed chicks), after which both groups were fed ad libitum until 4 or 13 days old. The lipid peroxidation level was higher in the delayed-fed than freely-fed chicks at 2, 4, and 13 days old. At 2 days old, the mRNA expressions of Cu/Zn-SOD, Mn-SOD, and GPX7 were lower in the delayed-fed than freely-fed chicks, while catalase mRNA levels did not differ. Furthermore, at 4 and 13 days old, lower mRNA expressions of Cu/Zn-SOD and Mn-SOD were observed in the delayed-fed than freely-fed chicks. These results suggest that delaying post-hatch feeding reduces the mRNA levels of Cu/Zn-SOD and Mn-SOD, consequently affecting muscle lipid peroxidation in chicks during subsequent growth.