Wellbeing and quality of life secondary outcomes from a Mediterranean Diet and walking randomised controlled trial in older Australians

OBJECTIVE: The Mediterranean Diet (MedDiet) and physical activity (PA) can enhance mood and support psychological wellbeing in adults. However, the combined effect is relatively unknown. MedWalk aimed to determine the combined effect on wellbeing, psychological health and quality of life (QoL), compared to a control group. DESIGN: This is an analysis of secondary outcomes from the MedWalk 12-month cluster-randomised controlled trial. Participants completed the Total and Secure Flourishing Index (FI), the four domain General Health Questionnaire (GHQ-28) and the 8-domain Assessment of Quality of Life (AQoL-8D). Data were analysed using general linear models using change scores (FI and AQoL-8D) or generalised linear mixed models with a time × group interaction effect (GHQ-28). SETTING: Independent living facilities across South Australia and Victoria in 2021-2022. PARTICIPANTS: One hundred and sixty-one older men and women. RESULTS: Participants were 74·9 ± 5·9 years of age and predominantly female (74 %). A greater improvement was found for the MedWalk group (marginal means (MM) = 1·65, se = 1·36) than the control group (MM = -2·50, se = 1·32) for the Total Flourish score (P = 0·003) and Secure Flourish score (P = 0·009) ((MM = 1·06, se = 1·65) v. (MM = -3·34, se = 1·61)) from baseline to 6 months. The MedWalk group (MM = 0·021, se = 0·014) had more positive changes (P = 0·048) to the Mental Health AQoL-8D domain than the control group (MM = -0·007, se = 0·014). No significant group × time interactions were identified for the GHQ-28. CONCLUSIONS: Combined MedDiet and walking interventions can modify psychological health, wellbeing and QoL in relatively healthy populations.