Heather Taylor

Abnormal cortisol levels during the day and cortisol awakening response in first-episode psychosis: The role of stress and of antipsychotic treatment

First-episode psychosis (FEP) patients show hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis, but the mechanisms leading to this are still unclear. The aim of this study was to investigate the role of stress and antipsychotic treatment on diurnal cortisol levels, and on cortisol awakening response, in FEP. Recent stressful events, perceived stress and childhood trauma were collected in 50 FEP patients and 36 healthy controls using structured instruments. Salivary cortisol was obtained at awakening, at 15, 30, and 60min after awakening, and at 12 and 8pm. Patients experienced more recent stressful events, perceived stress and childhood trauma than controls (p<0.001). Patients had a trend for higher diurnal cortisol levels (p=0.055), with those with less than two weeks of antipsychotics showing significantly higher cortisol levels than both patients with more than two weeks of antipsychotics (p=0.005) and controls (p=0.002). Moreover, patients showed a blunted cortisol awakening response compared with controls, irrespectively of antipsychotic treatment (p=0.049). These abnormalities in patients were not driven by the excess of stressors: diurnal cortisol levels were negatively correlated with the number of recent stressful events (r=-0.36, p=0.014), and cortisol awakening response was positively correlated with a history of sexual childhood abuse (r=0.33, p=0.033). No significant correlations were found between perceived stress or severity of symptoms and cortisol levels, either diurnal or in the awakening response. Our study shows that antipsychotics normalize diurnal cortisol hyper-secretion but not the blunted cortisol awakening response in FEP; factors other than the excess of psychosocial stress explain HPA axis abnormalities in FEP.

Higher cortisol levels are associated with smaller left hippocampal volume in first-episode psychosis.

This study investigated the relationship between cortisol secretion and hippocampal volume in first-episode psychosis and healthy controls. Hippocampal volume was measured by magnetic resonance imaging (MRI) in 24 first-episode psychosis patients and in 18 healthy controls, together with diurnal cortisol levels. Twelve patients received a second MRI scan at 3-month follow-up. Diurnal cortisol levels were inversely correlated with left hippocampal volume in patients, both at baseline and at follow-up, while no correlation was found in controls. Our findings suggest that smaller hippocampal volume in first-episode psychosis can partly be explained by stress-related processes in the brain, as measured by cortisol hyper-secretion.

Abnormal cortisol awakening response predicts worse cognitive function in patients with first-episode psychosis

BACKGROUND Cognitive impairment, particularly in memory and executive function, is a core feature of psychosis. Moreover, psychosis is characterized by a more prominent history of stress exposure, and by dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis. In turn, stress exposure and abnormal levels of the main HPA axis hormone cortisol are associated with cognitive impairments in a variety of clinical and experimental samples; however, this association has never been examined in first-episode psychosis (FEP). METHOD In this study, 30 FEP patients and 26 controls completed assessment of the HPA axis (cortisol awakening response and cortisol levels during the day), perceived stress, recent life events, history of childhood trauma, and cognitive function. The neuropsychological battery comprised general cognitive function, verbal and non-verbal memory, executive function, perception, visuospatial abilities, processing speed, and general knowledge. RESULTS Patients performed significantly worse on all cognitive domains compared to controls. In patients only, a more blunted cortisol awakening response (that is, more abnormal) was associated with a more severe deficit in verbal memory and processing speed. In controls only, higher levels of perceived stress and more recent life events were associated with a worse performance in executive function and perception and visuospatial abilities. CONCLUSIONS These data support a role for the HPA axis, as measured by cortisol awakening response, in modulating cognitive function in patients with psychosis; however, this association does not seem to be related to the increased exposure to psychosocial stressors described in these patients.

White matter integrity as a predictor of response to treatment in first episode psychosis.

The integrity of brain white matter connections is central to a patient’s ability to respond to pharmacological interventions. This study tested this hypothesis using a specific measure of white matter integrity, and examining its relationship to treatment response using a prospective design in patients within their first episode of psychosis. Diffusion tensor imaging data were acquired in 63 patients with first episode psychosis and 52 healthy control subjects (baseline). Response was assessed after 12 weeks and patients were classified as responders or non-responders according to treatment outcome. At this second time-point, they also underwent a second diffusion tensor imaging scan. Tract-based spatial statistics were used to assess fractional anisotropy as a marker of white matter integrity. At baseline, non-responders showed lower fractional anisotropy than both responders and healthy control subjects (P < 0.05; family-wise error-corrected), mainly in the uncinate, cingulum and corpus callosum, whereas responders were indistinguishable from healthy control subjects. After 12 weeks, there was an increase in fractional anisotropy in both responders and non-responders, positively correlated with antipsychotic exposure. This represents one of the largest, controlled investigations of white matter integrity and response to antipsychotic treatment early in psychosis. These data, together with earlier findings on cortical grey matter, suggest that grey and white matter integrity at the start of treatment is an important moderator of response to antipsychotics. These findings can inform patient stratification to anticipate care needs, and raise the possibility that antipsychotics may restore white matter integrity as part of the therapeutic response.

Acute effects of single-dose aripiprazole and haloperidol on resting cerebral blood flow (rCBF) in the human brain†

Antipsychotic drugs act on the dopaminergic system (first‐generation antipsychotics, FGA), but some also directly affect serotonergic function (second‐generation antipsychotics, SGA) in the brain. Short and long‐term effects of these drugs on brain physiology remain poorly understood. Moreover, it remains unclear whether any physiological effect in the brain may be different for FGAs and SGAs. Immediate (+3.30 h) and different effects of single‐dose FGA (haloperidol, 3 mg) and a SGA (aripiprazole, 10 mg) on resting cerebral blood flow (rCBF) were explored in the same 20 healthy volunteers using a pulsed continuous arterial spin labeling (pCASL) sequence (1.5T) in a placebo‐controlled, repeated measures design. Both antipsychotics increased striatal rCBF but the effect was greater after haloperidol. Both decreased frontal rCBF, and opposite effects of the drugs were observed in the temporal cortex (haloperidol decreased, aripiprazole increased rCBF) and in the posterior cingulate (haloperidol increased, aripiprazole decreased rCBF). Further increases were evident in the insula, hippocampus, and anterior cingulate after both antipsychotics, in the motor cortex following haloperidol and in the occipital lobe the claustrum and the cerebellum after aripiprazole. Further decreases were observed in the parietal and occipital cortices after aripiprazole. This study suggests that early and different rCBF changes are evident following a single‐dose of FGA and SGA. The effects occur in healthy volunteers, thus may be independent from any underlying pathology, and in the same regions identified as structurally and functionally altered in schizophrenia, suggesting a possible relationship between antipsychotic‐induced rCBF changes and brain alterations in schizophrenia. Hum Brain Mapp, 2013.

Childhood maltreatment is associated with increased body mass index and increased C-reactive protein levels in first-episode psychosis patients.

BACKGROUND The high incidence of the metabolic syndrome in patients with psychosis is mainly attributed to antipsychotic treatment. However, it is also possible that psychological stress plays a role, inducing a chronic inflammatory process that may predispose to the development of metabolic abnormalities. We investigated the association between childhood maltreatment and inflammatory and metabolic biomarkers in subjects with first-episode psychosis and healthy controls. METHOD Body mass index (BMI), weight and waist circumference were measured in 95 first-episode psychosis patients and 97 healthy controls. Inflammatory and metabolic markers were measured in a subsample of 28 patients and 45 controls. In all the subjects we collected information on childhood maltreatment and recent stressors. RESULTS Patients with childhood maltreatment had higher BMI [25.0 (S.E.=0.6) kg/m2] and C-reactive protein (CRP) levels [1.1 (S.E.=0.6) mg/dl] when compared with healthy controls [23.4 (S.E.=0.4) kg/m2, p=0.030 and 0.2 (S.E.=0.1) mg/dl, p=0.009, respectively]. In contrast, patients without childhood maltreatment were not significantly different from healthy controls for either BMI [24.7 (S.E.=0.6) kg/m2, p=0.07] or CRP levels [0.5 (S.E.=0.2) mg/dl, p=0.25]. After controlling for the effect of BMI, the difference in CRP levels across the three groups remained significant (F 2,58=3.6, p=0.035), suggesting that the increase in inflammation was not driven by an increase in adipose tissue. CONCLUSIONS Childhood maltreatment is associated with higher BMI, and increased CRP levels, in patients with a first-episode psychosis. Further studies need to confirm the mechanisms underlying the putative causal relationship between childhood maltreatment and higher BMI, and whether this is indeed mediated by increased inflammation.

Social Disadvantage: Cause or Consequence of Impending Psychosis?

Background: An association between social disadvantage and established psychosis is well documented in the literature, but there remains a lack of data on the social circumstances of patients before they became ill. We investigated whether social disadvantage at, and prior to, first contact with psychiatric services, is associated with psychosis. Method: We collected information on social disadvantage in childhood and adulthood from 278 cases presenting with their first episode of psychosis to the South London and Maudsley National Health Service Foundation Trust and from 226 controls recruited from the local population. Three markers of childhood social disadvantage and 3 markers of disadvantage in adulthood were analyzed. Results: Long term separation from, and death of, a parent before the age of 17 years were both strongly associated with a 2- to 3-fold-increased odds of psychosis. Cases were also significantly more likely to report 2 or more markers of adult social disadvantage than healthy controls (OR = 9.03) at the time of the first presentation with psychosis, independent of a number of confounders. When we repeated these analyses for long-standing adult social disadvantage, we found that the strength of the association decreased but still remained significant for 1 year (OR = 5.67) and 5 years (OR = 2.57) prior to the first contact. Conclusions: Social disadvantage indexes exposure to factors operating prior to onset that increase the risk of psychosis, both during childhood and adulthood.

Sexual dysfunction in people with prodromal or first-episode psychosis

BACKGROUND Sexual dysfunction is common in psychotic disorder but it is not clear whether it is intrinsic to the development of the illness or secondary to other factors. AIMS To compare sexual function in people at ultra-high risk (UHR) of a psychotic disorder, patients with first-episode psychosis predominantly taking antipsychotic drugs and healthy volunteers. METHOD Sexual function was assessed in a UHR group (n = 31), a group with first-episode psychosis (n = 37) and a matched control group of healthy volunteers (n = 56) using the Sexual Function Questionnaire. RESULTS There was a significant effect of group on sexual function (P<0.001). Sexual dysfunction was evident in 50% of the UHR group, 65% of first-episode patients and 21% of controls. Within the UHR group, sexual dysfunction was more marked in those who subsequently developed psychosis than in those who did not. Across all groups the severity of sexual dysfunction was correlated with the severity of psychotic symptoms (P<0.001). Within the first-episode group there was no significant difference in sexual dysfunction between patients taking prolactin-raising v. prolactin-sparing antipsychotics. CONCLUSIONS Sexual dysfunction is present prior to onset of psychosis, suggesting it is intrinsic to the development of illness unlikely to be related to the prolactin-raising properties of antipsychotic medication.

Globally Efficient Brain Organization and Treatment Response in Psychosis: A Connectomic Study of Gyrification

Background: Converging evidence suggests that patients with first-episode psychosis who show a poor treatment response may have a higher degree of neurodevelopmental abnormalities than good Responders. Characterizing the disturbances in the relationship among brain regions (covariance) can provide more information on neurodevelopmental integrity than searching for localized changes in the brain. Graph-based connectomic approach can measure structural covariance thus providing information on the maturational processes. We quantified the structural covariance of cortical folding using graph theory in first-episode psychosis, to investigate if this systems-level approach would improve our understanding of the biological determinants of outcome in psychosis. Methods: Magnetic Resonance Imaging data were acquired in 80 first-episode psychosis patients and 46 healthy controls. Response to treatment was assessed after 12 weeks of naturalistic follow-up. Gyrification-based connectomes were constructed to study the maturational organization of cortical folding. Results: Nonresponders showed a reduction in the distributed relationship among brain regions (high segregation, poor integration) when compared to Responders and controls, indicating a higher burden of aberrant neurodevelopment. They also showed reduced centrality of key regions (left insula and anterior cingulate cortex) indicating a marked reconfiguration of gyrification. Nonresponders showed a vulnerable pattern of covariance that disintegrated when simulated lesions removed high-degree hubs, indicating an abnormal dependence on highly central hub regions in Nonresponders. Conclusions: These findings suggest that a perturbed maturational relationship among brain regions underlies poor treatment response in first-episode psychosis. The information obtained from gyrification-based connectomes can be harnessed for prospectively predicting treatment response and prognosis in psychosis.

Connectomic correlates of response to treatment in first-episode psychosis.

Connectomic approaches using diffusion tensor imaging have contributed to our understanding of brain changes in psychosis, and could provide further insights into the neural mechanisms underlying response to antipsychotic treatment. We here studied the brain network organization in patients at their first episode of psychosis, evaluating whether connectome-based descriptions of brain networks predict response to treatment, and whether they change after treatment. Seventy-six patients with a first episode of psychosis and 74 healthy controls were included. Thirty-three patients were classified as responders after 12 weeks of antipsychotic treatment. Baseline brain structural networks were built using whole-brain diffusion tensor imaging tractography, and analysed using graph analysis and network-based statistics to explore baseline characteristics of patients who subsequently responded to treatment. A subgroup of 43 patients was rescanned at the 12-week follow-up, to study connectomic changes over time in relation to treatment response. At baseline, those subjects who subsequently responded to treatment, compared to those that did not, showed higher global efficiency in their structural connectomes, a network configuration that theoretically facilitates the flow of information. We did not find specific connectomic changes related to treatment response after 12 weeks of treatment. Our data suggest that patients who have an efficiently-wired connectome at first onset of psychosis show a better subsequent response to antipsychotics. However, response is not accompanied by specific structural changes over time detectable with this method.