Public Health

Background: In Japan, effective interventions to prevent low nutrition in older people with oral frailty have not been well established. This post-hoc sub-group analysis of the Japan-multimodal intervention trial for the prevention of dementia (J-MINT) aimed to examine the efficacy of the multidomain intervention in older adults with and without oral frailty.

Methods: J-MINT was an 18-month randomized controlled trial in which participants aged 65-85 years with mild cognitive impairment were randomized to a multimodal intervention group (physical exercise, nutrition counseling, cognitive training, and vascular risk factor management) and a control group. This study included the participants in J-MINT who had undergone the intervention program and follow-up evaluation at least once. Oral frailty was defined as oral frailty (Oral Frailty Index-8 ≥ 4 points) at baseline assessment. Outcomes were the change from baseline to 18-month assessment in cognitive function (the composite scores of eight neuropsychological tests), Body Mass Index (BMI), nutritional status (Mini Nutritional Assessment Short-Form), fat-free mass, fat mass, food diversity, and appetite (Council on Nutrition Appetite Questionnaire). A mixed model for the repeated measure was used to calculate the mean difference (MD) of outcome between the intervention and control groups.

Results: Of 531 participants enrolled in J-MINT, 433 participants were included (mean age: 74.4±4.9; women, 226; intervention group: 215), and 152 participants had oral frailty at baseline assessment. In older adults with oral frailty, although no significant mean difference in cognitive function was observed (MD [95%CI] = 0.099 [-0.019-0.217]), significant intervention effect in nutritional status (0.548 [0.034-1.062]), fat-free mass (0.842 [0.216-1.468]), fat mass (-0.962 [-1.890-0.038]), food diversity (1.263 [0.374-2.150]), and appetite (1.315 [0.524-2.110]) were observed. However, in older adults without oral frailty, there is a significant intervention effect in only food diversity (1.454 [0.808-2.100]).

Conclusion: The results of this study suggest the effectiveness of multimodal interventions on nutritional indicators for older adults with oral frailty. Oral frailty may be an effective target for multimodal intervention.