Cortisol levels predict psychosis risk
medwireNews: Cortical secretion is heightened in people at clinical high risk for psychosis, and it is associated with symptom severity and symptom progression, indicate initial findings from the North American Prodrome Longitudinal Study.
Although the ongoing study and follow ups are not complete, researchers say the findings suggest that hypersecretion of cortisol may characterize an etiologic subgroup.
Therefore, further study of the relationship between cortisol and brain abnormalities and the interplay between cortisol levels and receptor characteristics is warranted, they add.
Elaine Walker (Emory University, Atlanta, Georgia, USA) and colleagues studied baseline cortisol levels in 141 mentally healthy control individuals aged 19 years on average and 256 similarly aged individuals who were deemed to be prodromal and at clinical high risk for psychosis due to meeting the Scale of Prodromal Symptoms criteria on the Structured Interview for Prodromal Syndromes (SIPS).
Among the 256 prodromal individuals, 89% met criteria for attenuated positive symptom syndrome, 18% for genetic risk and deterioration syndrome, 14% for schizotypal personality disorder, and 3% for brief intermittent psychotic syndrome.
Salivary cortisol levels increased through the adolescent and early adult years in both groups, but analysis of covariance showed a main effect of diagnostic group.
Indeed, individuals who were prodromal had significantly higher cortisol levels than controls, at about 0.20 µg/dL versus 0.16 µg/dL.
Baseline cortisol levels also significantly correlated with symptom severity, with modest positive correlations with cortisol seen for the positive, negative, general and disorganized symptom ratings on SIPS. Among the general symptom domain, correlations with cortisol were also significant for dysphoric mood and impaired stress tolerance.
As it is an ongoing study and the final rate of conversion to psychosis is not yet known, the researchers studied the relationship between cortisol and psychosis transition in 136 of the prodromal individuals for whom 2-year data were available.
As reported in Biological Psychiatry, 32 individuals who had transitioned to a psychotic disorder at 2 years had significantly higher baseline cortisol levels (approximately 0.26 µg/dL) than the control group (0.16 µg/dL) and the 43 individuals who no longer had prodromal symptoms at 2 years (approximately 0.16 µg/dL).
"The symptoms of the CHR [clinical high-risk] syndromes are often subjectively stressful, and it is plausible that this distress activates the HPA [hypothalamic pituitary adrenal] axis," say Walker et al.
"Alternatively, as implied in diathesis-stress models, the causal relation may be in the opposite direction, such that biological stress systems trigger the expression of symptoms in some CHR individuals."
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By Lucy Piper, Senior medwireNews Reporter