Adherence to Mediterranean diet moderates the association between multimorbidity and depressive symptoms in older adults

•Adherence to Mediterranean Diet is known to be associated with lower risk for chronic diseases and depression.•Adherence to Mediterranean diet moderates the positive correlation between depressive symptoms and severity of medical multimorbidity.•Mediterranean diet may play an important role in mental health by decreasing the impact of multimorbidity on depressive symptoms. Adherence to Mediterranean Diet (Med-Diet) has been associated with a lower incidence of chronic diseases and may be associated with lower risk for depression. The aim of the present study was to investigate (i) the association of adherence to Med-Diet with depressive symptoms and multimorbidity in a cohort of geriatric medical outpatients, and (ii) the role of Med-Diet in mediating the association between depressive symptoms and multimorbidity. A total of 143 geriatric patients (mean age: 73.1 ± 8.35) were included. Adherence to Med-Diet was evaluated using a validated 14-item questionnaire; depressive and cognitive symptoms were assessed through the 15-item Geriatric Depression Scale (GDS) and Mini Mental State Examination (MMSE) respectively; multimorbidity was evaluated using the Cumulative Illness Rating Scale for Geriatrics (CIRSG-SI). Significant associations were found between MDQ score, GDS and CIRSG-SI (MDQ score and GDS: r= -0.206, p = 0.014; MDQ score and CIRSG-SI: r= -0.247, p = 0.003; GDS and CIRSG-SI: r = 0.251; p = 0.003). These associations remained significant after adjusting for potential confounding factors. A mediational model analysis showed that the direct effect of CIRSG-SI on GDS was significant (b = 1.330; se = 0.59; p = 0.028) with this effect being counterbalanced by higher MDQ scores (indirect effect of CIRS-G on GDS through MDQ: b = 0.382; se = 0.19; p = 0.048). These findings (i) add to the accumulating evidence that Med-Diet may have a positive impact on mental health in the elderly, and (ii) suggest that Med-Diet may contribute, at least in part, to protect geriatric patients with multimorbidity from the development of depressive symptoms, ultimately promoting healthy aging.