Article

Olfaction and schizophrenia clinical risk status: Just the facts

Neuropsychiatry Division, Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
Schizophrenia Research (Impact Factor: 4.43). 05/2012; 139(1-3):260-1; author reply 262-3. DOI: 10.1016/j.schres.2012.04.016
Source: PubMed
Download full-text

Full-text

Available from: Paul J Moberg, Jul 14, 2014
1 Follower
 · 
211 Views
 · 
41 Downloads
  • Source
    • "This would imply that OI deficits are detectable in at-risk populations before the onset of frank psychotic illness. Indeed there is evidence that young people clinically at ultrahigh risk (UHR) for psychosis also show impaired OI (Brewer et al., 2003; Kamath et al., 2014, 2012; Woodberry et al., 2010), with a pooled medium to large effect size (Moberg et al., 2013; Turetsky et al., 2012). "
    [Show abstract] [Hide abstract]
    ABSTRACT: We have previously reported that olfactory identification (OI) deficits are a promising premorbid marker of transition from ultra-high risk (UHR) to schizophrenia, but not to psychotic illness more generally. Whether this remains the case at longer follow-up, and whether there is decline in OI ability are unclear. The University of Pennsylvania Smell Identification Test (UPSIT) was administered to 81 participants at baseline (identification of risk for psychosis) and 254 individuals at follow-up. Forty-nine participants underwent UPSIT assessment at both time points. UPSIT scores were investigated at an average of 7.08years after identification of risk in relation to transition to psychosis, a diagnosis of schizophrenia, and psychosocial/functional outcome. UPSIT scores at baseline and follow-up did not differ between participants who transitioned to psychosis and those who did not. Similarly, there were no significant differences on UPSIT scores at baseline or follow-up between individuals with a diagnosis of schizophrenia and transitioned individuals without schizophrenia. Those with a poor functional outcome showed significantly lower baseline UPSIT scores than participants with good outcome. There was no significant association between functional outcome and follow-up UPSIT scores. There were no significant changes in UPSIT over time for any group. These results suggest that impaired OI is not a good marker of the onset of psychosis and schizophrenia, but may differentiate UHR individuals who experience a poor functional outcome, regardless of transition status. Copyright © 2014 Elsevier B.V. All rights reserved.
    Schizophrenia Research 12/2014; 161(2-3). DOI:10.1016/j.schres.2014.10.051 · 4.43 Impact Factor
  • Source
    • "schizotypy, unaffected family members and genetic high-risk subjects (Moberg et al., 2014). Future studies in large CHR cohorts, similarly attentive to diagnosis, ascertainment and potential moderating factors (Moberg et al., 2014), will inform the utility of SID as a risk biomarker for schizophrenia, which may also resolve some of the debate in the field as to the relevance of SID in risk populations (Cohen et al., 2012; Turetsky et al., 2012). The examination of SID in a larger cohort could also allow closer examination of gender differences in olfactory function (Malaspina et al., 2012) in CHR subjects. "
    [Show abstract] [Hide abstract]
    ABSTRACT: 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.
    Psychiatry Research 07/2014; 220(1-2). DOI:10.1016/j.psychres.2014.07.018 · 2.68 Impact Factor
  • Source
    • "On the other hand, we found no abnormality in the cavum septum pellucidum (CSP) that is also related to fetal neurodevelopment (Rakic and Yakovlev, 1968) in UHR individuals (Takahashi et al., 2008b), suggesting different biological processes responsible for these gross brain abnormalities. A recent MRI study demonstrated decreased olfactory sulcus depth in a Japanese high-risk sample (Takahashi et al., 2013b), supporting the notion that olfactory impairment appears to be a promising vulnerability marker of the psychosis risk status especially for those who subsequently develop schizophrenia (Brewer et al., 2003; Turetsky et al., 2012). However, that preliminary MRI study could not take account of sample outcome (e.g., with and without later transition) due to small sample size and needs replication in a larger well-defined high-risk cohort. "
    [Show abstract] [Hide abstract]
    ABSTRACT: A shallow olfactory sulcus has been reported in schizophrenia, possibly reflecting abnormal forebrain development during early gestation. However, it remains unclear whether this anomaly exists prior to the onset of psychosis and/or differs according to illness stage. In the current study, magnetic resonance imaging was used to investigate the length and depth of the olfactory sulcus in 135 ultra high-risk (UHR) individuals [of whom 52 later developed psychosis (UHR-P) and 83 did not (UHR-NP)], 162 patients with first-episode psychosis (FEP), 89 patients with chronic schizophrenia, and 87 healthy controls. While there was no group difference in the length of the sulcus, UHR-P subjects had significantly shallower olfactory sulcus at baseline as compared with UHR-NP and control subjects. The depth of this sulcus became increasingly more superficial as one moved from UHR-P subjects to FEP patients to chronic schizophrenia patients. Finally, the depth of the olfactory sulcus in the UHR-P subjects was negatively correlated with the severity of negative symptoms. These findings suggest that the altered depth of the olfactory sulcus, which exists before psychosis onset, could be predictive of transition to psychosis, but also suggest ongoing changes of the sulcus morphology during the course of the illness.
    Schizophrenia Research 03/2014; 153(1-3). DOI:10.1016/j.schres.2014.01.041 · 4.43 Impact Factor
Show more