Julie Messinger

Avolition and expressive deficits capture negative symptom phenomenology: Implications for DSM-5 and schizophrenia research

The DSM-5 formulation presents an opportunity to refine the negative symptom assessments that are crucial for a schizophrenia diagnosis. This review traces the history of negative symptom constructs in neuropsychiatry from their earliest conceptualizations in the 19th century. It presents the relevant literature for distinguishing between different types of negative symptoms. Although a National Institute of Mental Health consensus initiative proposed that there are five separate negative symptom domains, our review of the individual items demonstrates no more than three negative symptom domains. Indeed, numerous factor analyses of separate negative symptom scales routinely identify only two domains: 1) expressive deficits, which include affective, linguistic and paralinguistic expressions, and 2) avolition for daily life and social activities. We propose that a focus on expressive deficits and avolition will be of optimum utility for diagnosis, treatment-considerations, and research purposes compared to other negative symptom constructs. We recommend that these two domains should be assessed as separate dimensions in the DSM-5 criteria.

Later paternal age and sex differences in schizophrenia symptoms

OBJECTIVE Advanced paternal age is consistently associated with an increased risk for schizophrenia, accounting for up to a quarter of cases in some populations. If paternal age-related schizophrenia (PARS) involves a distinct etiopathology, then PARS cases may show specific characteristics, vis-à-vis other schizophrenia cases. This study examined if PARS exhibits the symptom profile and sex differences that are consistently observed for schizophrenia in general, wherein males have an earlier onset age and more severe negative symptoms than females. METHOD Symptoms were assessed at baseline (admission) and during medication-free and treatment phases for 153 inpatients on a schizophrenia research unit, 38 of whom fulfilled operationally defined criteria for PARS (sporadic cases with paternal age > or = 35). RESULTS Males and females with PARS had the same age at onset and a similar preponderance of negative symptoms, whereas the other (non-PARS) cases showed the typical earlier onset age and more severe negative symptoms in males. When medications were withdrawn, PARS cases showed significantly worse symptoms than non-PARS cases (higher total PANSS scores and positive, activation, and autistic preoccupation scores). However these symptoms globally improved with antipsychotic treatment, such that the differences between the PARS and other schizophrenia cases receded. CONCLUSION The lack of sex differences in the age at onset and the greater severity of medication-free symptoms bolster the hypothesis that PARS has a distinct etiopathology. It also suggests that female sex does not exert a protective effect on the course of PARS, as it may in other forms of schizophrenia.

Olfactory acuity is associated with mood and function in a pilot study of stable bipolar disorder patients

OBJECTIVES Olfactory dysfunction is described in several neuropsychiatric disorders but there is little research on olfactory processing in bipolar disorder. METHODS We assessed odor detection threshold (sensitivity) and smell identification test scores, along with symptoms, cognition, and social function in 20 DSM-IV bipolar disorder patients and 44 control subjects. RESULTS The patient and control groups had similar demographic measures, intelligence, and mean olfaction scores, but significantly differed in social domains, including adjustment, function, and anxiety. Odor detection sensitivity showed significantly opposite correlations for the depressive and manic mood domains in bipolar disorder (r to z = 2.83, p = 0.005). Depressive symptoms were related to increased sensitivity (the ability to detect odors at a lower concentration) and mania symptoms were related to decreased sensitivity for odor detection. Increased sensitivity for odor detection also predicted significantly better employment (r = -0.642, p = 0.024), whereas less sensitivity was associated with social avoidance (r = 0.702, p =0.024) and social fear (r = 0.610, p = 0.046). CONCLUSIONS Diminished odor detection sensitivity predicted mania and social avoidance, whereas more sensitive odor detection predicted more depressive symptoms but better employment functioning in bipolar disorder patients. Odor acuity may be an illness state marker of mood syndromes in bipolar disorder. Alternatively, differences in odor acuity may identify heterogeneous subgroups within the bipolar spectrum. Longitudinal assessments in a large, sex-stratified sample are needed to understand the implications of odor sensitivity in patients with bipolar disorder.

Olfactory processing, sex effects and heterogeneity in schizophrenia

INTRODUCTION Smell identification deficits are associated with negative symptoms in schizophrenia, particularly in males. Far less information is known about the relationship of odor detection sensitivity (acuity) and negative symptoms in schizophrenia, and currently there is a dearth in sex-stratified research specifically examining odor sensitivity and smell identification. METHODS Fifty-eight individuals with schizophrenia and 42 healthy comparison subjects were assessed on tests of odor sensitivity, smell identification and cognition. Negative symptoms were assessed with the Positive and Negative Syndrome Scale and the Schedule for the Deficit Syndrome. RESULTS In healthy males, increased odor detection sensitivity predicted better smell identification scores. In contrast, male schizophrenia patients showed a significant inverse relationship, in which increased odor sensitivity predicted lower smell identification scores. Odor sensitivity and smell identification were unrelated in both schizophrenia and healthy females. Olfactory processing was strongly linked to negative symptoms, but the relationships differed by sex. Emotional expression deficits were related to odor detection hypersensitivity in female patients, whereas smell identification deficits predicted these emotional deficits in male cases. CONCLUSION Sex differences in olfactory functioning were identified in healthy subjects and in schizophrenia patients. Smell identification was related to negative symptoms in males with schizophrenia, whereas odor detection sensitivity predicted these features in females. Sex differences should be considered in future analyses that employ odor stimuli for neuropsychiatric research.

Smell identification in individuals at clinical high risk for schizophrenia

Smell identification deficits exist in schizophrenia, and may be associated with its negative symptoms. Less is known about smell identification and its clinical correlates in individuals at clinical high risk (CHR) for schizophrenia and related psychotic disorders. We examined smell identification, symptoms and IQ in 71 clinical high-risk (CHR) subjects and 36 healthy controls. Smell identification was assessed using both the 40-item University of Pennsylvania Smell Identification Test (UPSIT; Doty, R.L., Shaman, P., Kimmelman, C.P., Dann, M.S., 1984. University of Pennsylvania Smell Identification Test: a rapid quantitative olfactory function test for the clinic. Laryngoscope 94, 176-178) and its extracted 12-item Brief Smell Identification Test (Goudsmit, N., Coleman, E., Seckinger, R.A., Wolitzky, R., Stanford, A.D., Corcoran, C., Goetz, R.R., Malaspina, D., 2003. A brief smell identification test discriminates between deficit and non-deficit schizophrenia. Psychiatry Research 120, 155-164). Smell identification did not significantly differ between CHR subjects and controls. Among CHR subjects, smell identification did not predict schizophrenia (N=19; 27%) within 2 years, nor was it associated with negative or positive symptoms. This is the third prospective cohort study to examine smell identification in CHR subjects, and overall, findings are inconclusive, similar to what is found for other disorders in adolescents, such as autism spectrum, attention deficit and anxiety disorders. Smell identification deficit may not have clear utility as a marker of emergent schizophrenia and related psychotic disorders.

Olfaction and Cognition in Schizophrenia: Sex Matters

Cognitive and olfactory deficits occur in schizophrenia, but little is known whether sex modifies these deficits. We examined the relationship between olfaction and cognition in 55 schizophrenia patients and 32 healthy controls. Patients and controls demonstrated significant differences performing cognitive tasks. In patients, sex modified all relationships of odor identification to cognition. Female patients showed significantly stronger trends than male patients correlating better smell identification with higher scores on intelligence, memory, and attention, whereas their correlations of odor identification with executive functioning contradicted those of male patients. Odor acuity significantly correlated with several cognitive measures, especially in male patients, in whom better acuity was generally associated with better cognition. Female patients again differed significantly from males; odor acuity correlations with cognitive measures were weaker, or contradicted, those of male patients. These findings indicate significant sex differences in olfactory processing in schizophrenia. Combining the sexes in research analyses may obscure important differences.

Critical periods and the developmental origins of disease: an epigenetic perspective of schizophrenia.

Epigenetics holds promise to explain some puzzles concerning the risk and course of psychiatric disorders. Epigenetic information is essential as a set of operating instructions for the genome, which is heritable with DNA. The epigenetic regulation of gene expression can plausibly be influenced by the environment of ones ancestors, prenatal exposures, and by early life events. Some epigenetic mechanisms may alter neurophysiology throughout life by programming gene expression, perhaps in anticipation of certain life experiences. These epigenetic signals are only meta‐stable and may be perturbed by stochastic events, errors, or by environmental toxins. This introduction considers the possibility that epigenetic change that may occur as paternal age advances or during fetal adversity may be causally related to the susceptibility for schizophrenia.

Multivoxel Proton MR Spectroscopy Used to Distinguish Anterior Cingulate Metabolic Abnormalities in Patients with Schizophrenia

PURPOSE To test the hypothesis that anterior cingulate cortex (ACC) subregions in patients with schizophrenia are metabolically different from those in healthy control subjects. MATERIALS AND METHODS This institutional review board-approved study was HIPAA compliant, and all participants provided written informed consent. Twenty-two patients with schizophrenia (13 male, nine female; 39.4 years ± 10.6 [standard deviation]) and 11 age- and sex-matched control subjects (seven male, four female; 35.5 years ± 10.7) underwent magnetic resonance (MR) imaging and three-dimensional 3-T voxel proton MR spectroscopy to measure absolute rostral and caudal ACC N-acetylaspartate (NAA), creatine (Cr), and choline (Cho) concentrations. Exact Mann-Whitney test was used to compare patient data with control data, paired-sample Wilcoxon signed rank test was used to compare subregions within groups, and receiver operating characteristic curve analysis was used to assess sensitivity and specificity in diagnosis of schizophrenia. RESULTS There were no significant metabolic differences between patients and control subjects or between ACC subregions in control subjects. In patients, rostral ACC NAA and Cr concentrations were significantly lower than those in caudal ACC (6.2 mM ± 1.3 vs 7.1 mM ± 1.3, P < .01; 5.7 mmol/L ± 1.4 vs 6.3 mmol/L ± 1.6, P < .01; respectively); however, this did not hold true for Cho concentrations (1.7 mmol/L ± 0.5 vs 1.8 mmol/L ± 0.5). For individual differences between caudal and rostral measurements, only NAA in patients was different from that in control subjects (0.9 mmol/L ± 1.3 vs -0.1 mmol/L ± 0.5, P < .01), enabling prediction of schizophrenia with 68% sensitivity and 91% specificity, for a difference of more than 0.4. CONCLUSION Significant differences between caudal and rostral NAA concentration are found in ACC of patients with schizophrenia but not in ACC of healthy control subjects, indicating that neuronal density or integrity differences between ACC subregions may be characteristic of the disease.

Epidemiology Research and Epigenetics: Translational Epidemiology of Schizophrenia

Epigenetic processes can explain some of the epidemiological associations between environmental exposure and disease, particularly when the exposure occurs at a critical developmental stage. In this chapter, we present several epigenetic pathways associated with the risk for schizophrenia. We discuss nongenetic factors – such as paternal age, toxin exposure, and psychological stressors – which may influence human development by way of epigenetic mechanisms.