RESUMO
INTRODUCTION: Chronic undernutrition and a homebound state are corelated and are both important components of frailty. However, whether social network intervention combined with protein supplementation is an effective strategy to prevent functional decline among frail older adults is unclear. METHODS: 150 frail older adults participated in a 3-month, 3-armed, community-based clinical trial and were randomly assigned to one of 3 groups: high-protein supplementation (additional 27 g of protein/day), the Social Nutrition Program (additional 27 g of protein/day and social network intervention), or a control group. Those assigned to the Social Nutrition Program group received individual counseling from 1 dietitian and 1 social worker during 6 home visits and were encouraged to participate in 4 sessions of community-based cooking activities, the social kitchen program. Primary outcomes were changes in Physical Functioning (PF) and the Timed Up and Go (TUG) test and were assessed at 0 months (baseline), 1.5 months (interim), and 3, 6, and 9 months (postintervention). RESULTS: Compared with the control group, participants in the Social Nutrition Program showed an average improvement of 2.2-3.0 s in the TUG test and this improvement persisted for 3 months after the end of the program (post hoc p ≤ 0.030). The Social Nutrition Program also increased PF by 1.3 points while the control group showed a 1.4 point reduction at the end of the program (post hoc p = 0.045). Improvement in PF and TUG results was primarily observed for the socially frail subgroup of older adults in the Social Nutrition Program group rather than the physically frail subgroup. Frequency of leaving home functioned as a mediator (p = 0.042) and explained 31.2% of the total effect of the Social Nutrition Program on PF change. CONCLUSION: Our results indicate that social network intervention combined with protein supplementation can improve both the magnitude and duration of functional status among frail older community-dwelling adults.