Postoperative cognitive dysfunction (POCD) is characterized by a cognitive decline from pre- to post-surgery assessment, but is underresearched from an epidemiological perspective. Previous studies have identified metabolic dysfunction as a risk factor for age-related cognitive impairment (ACI) which too is characterized by cognitive deficits but occurs in the general population during ageing. Thus, metabolic dysfunction is a strong candidate risk factor for POCD. Here, I used a total of 4 surgical cohort studies of middle-aged to older adults with extensive anthropometric, clinical (and in part molecular) phenotyping as well as detailed pre- and post-surgical cognitive assessment to test the hypothesis that ACI and POCD share metabolic risk factors. I found partial evidence for in favor of this hypothesis. The implications of this work are three-fold: i) the findings suggest that ACI and POCD may (in part) be driven by similar pathophysiological mechanisms. ii) by measuring metabolic function before surgery, we may be able to risk stratify older surgical patients and – in elective surgery settings – empower at-risk patients for informed decision making. ii) if future work determines that the associations found here reflect causal relationships of metabolic dysfunction with ACI and POCD, we could set up preventive measures. Ultimately, the epidemiological analyses presented here provide one step towards a better understanding of ACI and POCD.
