Psychosis and cognition: the link with cortisol may depend on measurement time

A review focused on psychotic disorders

The researchers examined associations between cortisol and cognition in the context of psychotic disorders. Their systematic review includes twelve studies and 940 participants, about three quarters of whom have a psychotic disorder.

Nine studies, totaling 822 participants, provided usable data for the meta-analyses. The analyses covered basal cortisol and several cognitive domains: overall performance, attention, working memory, processing speed, executive function, learning, and verbal memory.

The source material provides access only to the PubMed abstract, not the full text. Study durations, detailed sampling procedures, and the characteristics of comparison groups therefore cannot be specified here.

A specific signal, not an overall association

The main finding concerns sampling time. Higher afternoon or evening cortisol was associated with poorer executive performance. Measurement time significantly moderated the observed relationship between cortisol and executive function.

The authors find no other robust association between cortisol and cognition. A sensitivity analysis reveals a negative association between morning cortisol and the domain combining attention, working memory, and processing speed, but only after excluding one influential study. This finding therefore depends on which studies are included.

What this study tells us

These findings challenge the simple interpretation that more cortisol consistently means poorer cognition. In this review, the association depends on both the cognitive domain and the sampling time.

These are associations, not findings from a trial designed to alter cortisol levels. The review therefore does not show that lowering cortisol would improve executive function. Nor does it support extending the findings to people without a psychotic disorder.

The authors call for more precise assessments of cortisol dynamics. Funding and conflicts of interest are not reported in the excerpt provided and could not be verified.

What we can take away

In psychotic disorders, the link between basal cortisol and cognition appears specific rather than general. The signal observed late in the day warrants further investigation, but does not justify an intervention to lower cortisol.