Positive affect predicts cerebral glucose metabolism in late middle-aged adults

Abstract

Positive affect is associated with a number of health benefits; however, few studies have examined the relationship between positive affect and cerebral glucose metabolism, a key energy source for neuronal function and a possible index of brain health. We sought to determine if positive affect was associated with cerebral glucose metabolism in late middle-aged adults (n = 133). Participants completed the positive affect subscale of the Center for Epidemiological Studies Depression Scale at two time points over a two-year period and underwent 18F-fluorodeoxyglucose-positron emission tomography scanning. After controlling for age, sex, perceived health status, depressive symptoms, anti-depressant use, family history of Alzheimer’s disease, APOE ε4 status and interval between visits, positive affect was associated with greater cerebral glucose metabolism across para-/limbic, frontal, temporal and parietal regions. Our findings provide evidence that positive affect in late midlife is associated with greater brain health in regions involved in affective processing and also known to be susceptible to early neuropathological processes. The current findings may have implications for interventions aimed at increasing positive affect to attenuate early neuropathological changes in at-risk individuals.

SPECT and PET in Late-Life Depression

“…It is thus not surprising that measurements of cerebral glucose metabolism using the PET tracer 18 F-FDG have produced findings which are quite similar to those acquired with flow tracers (see Table 5.2). FDG-PET studies also support the concept that LLD relies on dysfunctioning (i.e., reduced metabolism) of the frontal lobe (Kuhl et al 1985;Mayberg et al 1990;Kumar et al 1993;Hirono et al 1998;Mentis et al 2002;Holthoff et al 2005;Herting et al 2007;Fujimoto et al 2008;Lee et al 2010;Sakurai et al 2017;Nicholas et al 2017;Youn et al 2018), whereas the involvement of other brain regions has also been reported (Krell-Roesch et al 2016), but seems more variable and controversial. In one study, successful antidepressant treatment was found to be associated with increases of glucose metabolism (Marano et al 2013).…”