The moderation of multimorbidity and depressive symptoms on cognition.

Abstract

Multimorbidity, or the occurrence of two or more chronic conditions, is a global challenge, with implications for mortality, morbidity, disability and life quality. Psychiatric disorders are common among the chronic diseases that affect patients with multimorbidity. It is still not well understood whether psychiatric symptoms, especially depressive symptoms, moderate the effect of multimorbidity on cognition. We used a large (n=2681) dataset to assess whether there is a moderation of depressive symptomatology on the effect of multimorbidity on cognition using structural equation modelling. It was found that the more depressive symptoms and chronic conditions, the worse the cognitive performance, and the higher the educational level, the better the cognitive performance. We found a significant but weak (0.009; p-value = 0.04) moderation effect. We have provided the first estimate of the moderating effect of depression on the effect of multimorbidity on cognition, though it is small. Although this moderation was implicit in numerous previous works, it was never previously estimated.