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Dive into the research topics where Rianne Klaassen is active.

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Featured researches published by Rianne Klaassen.


Schizophrenia Research | 2009

Baseline differences in clinical symptomatology between ultra high risk subjects with and without a transition to psychosis.

Dorien H. Nieman; Hiske E. Becker; Reinaud van de Fliert; Peter Dingemans; Rianne Klaassen; Lieuwe de Haan; Therese van Amelsvoort; Don Linszen

BACKGROUND The chance of transition to psychosis in patients at Ultra High Risk for developing psychosis (UHR) is 10-15%. The aim of present study was to investigate differences in baseline clinical symptomatology, general level of functioning (GAF-score) and genetic risk between UHR patients who did (UHR+T) or did not (UHR+NT) make a transition to psychosis. Sharpening UHR inclusion criteria may aid in improving prediction of transition to psychosis. METHOD The study sample was taken from 285 patients who were examined within the Dutch Prediction of Psychosis Study (DUPS) at the Academic Medical Center of the University of Amsterdam, the Netherlands. Out of 73 included UHR subjects, 18 made a transition to psychosis. Psychopathology was investigated with the Structured Interview for Prodromal Syndromes, Bonn Scale for the Assessment of Basic Symptoms and GAF-score. The follow-up period of the study was three years. RESULTS The UHR+T group showed more social anhedonia and withdrawal, more bizarre thinking and a lower GAF score at baseline than the UHR+NT group. CONCLUSIONS In agreement with the results of Cannon et al. [Cannon, T.D., Cadenhead, K., Cornblatt, B., Woods, S.W., Addington, J., Walker, E., Seidman, L.J., Perkins, D., Tsuang, M., McGlashan, T., Heinssen, R., 2008. Prediction of Psychosis in Youth at High Clinical Risk: A Multisite Longitudinal Study in North America. Arch. Gen. Psychiat. 65 (1) 28-37.], our study indicates that severity of specific symptoms at baseline is related to transition to psychosis in UHR subjects. These findings may contribute to a more accurate prediction of a first psychotic episode. Furthermore, symptoms that are increased at baseline in the UHR+T group could be a focus of cognitive behavioural therapy in the UHR period.


Schizophrenia Bulletin | 2012

Cognitive Behavioral Therapy for Subjects at Ultrahigh Risk for Developing Psychosis: A Randomized Controlled Clinical Trial

Mark van der Gaag; Dorien H. Nieman; Judith Rietdijk; Sara Dragt; Helga K. Ising; Rianne Klaassen; Maarten W. J. Koeter; Pim Cuijpers; Lex Wunderink; Don Linszen

BACKGROUND Evidence for the effectiveness of treatments for subjects at ultrahigh risk (UHR) for developing psychosis remains inconclusive. OBJECTIVE A new cognitive behavioral intervention specifically targeted at cognitive biases (ie, Cognitive Behavioral Therapy [CBT] for UHR patients plus treatment as usual [TAU] called CBTuhr) is compared with TAU in a group of young help-seeking UHR subjects. METHODS A total of 201 patients were recruited at 4 sites and randomized. In most cases, CBTuhr was an add-on therapy because most people were seeking help for a comorbid disorder. The CBT was provided for 6 months, and the follow-up period was 18 months. RESULTS In the CBTuhr condition, 10 patients transitioned to psychosis compared with 22 in the TAU condition (χ(2) (1) = 5.575, P = .03). The number needed to treat (NNT) was 9 (95% confidence interval [CI]: 4.7-89.9). At 18-month follow-up the CBTuhr group was significantly more often remitted from an at-risk mental state, with a NNT of 7 (95% CI: 3.7-71.2). Intention-to-treat analysis, including 5 violations against exclusion criteria, showed a statistical tendency (χ(2) (1) = 3.338, P = .06). CONCLUSIONS Compared with TAU, this new CBT (focusing on normalization and awareness of cognitive biases) showed a favorable effect on the transition to psychosis and reduction of subclinical psychotic symptoms in subjects at UHR to develop psychosis.


Schizophrenia Research | 2014

Duration of untreated psychosis and negative symptoms ? A systematic review and meta-analysis of individual patient data

Nynke Boonstra; Rianne Klaassen; Sjoerd Sytema; Max Marshall; Lieuwe de Haan; L. Wunderink; Durk Wiersma

BACKGROUND Longer duration of untreated psychosis (DUP) is associated with poorer outcome in terms of positive symptoms, relapse rate, and time to remission. In contrast, the association with negative symptoms is less consistent. AIMS The study had three aims. First, to arrive at a more precise estimate of the correlation between DUP and negative symptoms than previous reviews, by substantially increasing the amount of available data. Second, to see whether the strength of this correlation attenuated over longer follow-up intervals. Third, to determine whether there is a relationship between DUP and changes in negative symptoms. METHOD Relevant databases were searched for studies published between December 1992 and March 2009 that reported data on DUP and negative symptoms. We obtained individual patient data where possible and calculated summary correlations between DUP and negative symptoms for each study at baseline, short and long-term follow-up. We used multilevel regression analysis to examine whether the effect of DUP on negative symptoms was the greatest in the early stages of illness. RESULTS We included 28 non-overlapping studies from the 402 papers detected by the search strategy. After contacting the authors we obtained individual patient data from 16 of these studies involving 3339 participants. The mean DUP was 61.4 weeks (SD=132.7, median DUP=12.0). Shorter DUP was significantly associated with less severe negative symptoms at baseline and also at short (1-2 years) and longer term follow-up (5-8 years) (r=0.117, 0.180 and 0.202 respectively, p<0.001). The relationship between improvement in negative symptoms and DUP was found to be non-linear: people with a DUP shorter than 9 months showed substantially greater negative symptom reduction than those with a DUP of greater than 9 months. CONCLUSIONS Shorter DUP is associated with less severe negative symptoms at short and long-term follow up, especially when the DUP is less than 9 months. Since there is no effective treatment for negative symptoms, reducing DUP to less than 9 months may be the best way to ameliorate them.


Schizophrenia Bulletin | 2012

The Validity of the 16-Item Version of the Prodromal Questionnaire (PQ-16) to Screen for Ultra High Risk of Developing Psychosis in the General Help-Seeking Population

Helga K. Ising; Wim Veling; Rachel Loewy; Marleen W. Rietveld; Judith Rietdijk; Sara Dragt; Rianne Klaassen; Dorien H. Nieman; Lex Wunderink; Don Linszen; Mark van der Gaag

In order to bring about implementation of routine screening for psychosis risk, a brief version of the Prodromal Questionnaire (PQ; Loewy et al., 2005) was developed and tested in a general help-seeking population. We assessed a consecutive patient sample of 3533 young adults who were help-seeking for nonpsychotic disorders at the secondary mental health services in The Hague with the PQ. We performed logistic regression analyses and CHi-squared Automatic Interaction Detector decision tree analysis to shorten the original 92 items. Receiver operating characteristic curves were used to examine the psychometric properties of the PQ-16. In the general help-seeking population, a cutoff score of 6 or more positively answered items on the 16-item version of the PQ produced correct classification of Comprehensive Assessment of At-Risk Mental State (Yung et al., 2005) psychosis risk/clinical psychosis in 44% of the cases, distinguishing Comprehensive Assessment of At-Risk Mental States (CAARMS) diagnosis from no CAARMS diagnosis with high sensitivity (87%) and specificity (87%). These results were comparable to the PQ-92. The PQ-16 is a good self-report screen for use in secondary mental health care services to select subjects for interviewing for psychosis risk. The low number of items makes it quite appropriate for screening large help-seeking populations, thus enhancing the feasibility of detection and treatment of ultra high-risk patients in routine mental health services.


Acta Psychiatrica Scandinavica | 2012

Detection of people at risk of developing a first psychosis: comparison of two recruitment strategies

Judith Rietdijk; Rianne Klaassen; Helga K. Ising; Sara Dragt; Dorien H. Nieman; J.M. van de Kamp; Pim Cuijpers; D.H. Linszen; M. van der Gaag

Rietdijk J, Klaassen R, Ising H, Dragt S, Nieman DH, van de Kamp J, Cuijpers P, Linszen D, van der Gaag M. Detection of people at risk of developing a first psychosis: comparison of two recruitment strategies.


Trials | 2010

A single blind randomized controlled trial of cognitive behavioural therapy in a help-seeking population with an At Risk Mental State for psychosis: the Dutch Early Detection and Intervention Evaluation (EDIE-NL) trial

Judith Rietdijk; Sara Dragt; Rianne Klaassen; Helga K. Ising; Dorien H. Nieman; Lex Wunderink; Philippe Delespaul; Pim Cuijpers; Don Linszen; Mark van der Gaag

BackgroundPsychotic disorders are a serious mental health problem. Intervention before the onset of psychosis might result in delaying the onset, reducing the impact or even preventing the first episode of psychosis. This study explores the effectiveness of cognitive behavioural therapy (CBT) in targeting cognitive biases that are involved in the formation of delusions in persons with an ultra-high risk for developing psychosis. A single blind randomised controlled trial compares CBT with treatment as usual in preventing or delaying the onset of psychosis.Method/designAll help seeking patients aged 14 to 35 years referred to the mental health services in three regions in the Netherlands are pre-screened with the Prodromal Questionnaire during a period of two years. Patients with a score of 18 or more on the sub-clinical positive symptoms items (45 items in total) will be assessed with the Comprehensive Assessment of At Risk Mental State (CAARMS). In a different pathway to care model all referrals from the mental health services in Amsterdam to the specialized psychosis clinic of the Academic Medical Centre in Amsterdam are also assessed with the CAARMS. The primary outcome is the transition rate to psychosis according to the CAARMS-criteria. Group differences will be analysed with chi-square tests and survival analyses.DiscussionCBT is a highly tolerated treatment. The psycho-educational CBT approach may prove to be a successful strategy since most people with an At Risk Mental State (ARMS) are distressed by odd disturbing experiences. Giving explanations for and normalising these experiences may reduce the arousal (distress) and therefore may prevent people from developing a catastrophic delusional explanation for their odd experiences and thus prevent them from developing psychosis.Screening the entire help-seeking population referred to community mental health services with a two-stage strategy, as compared with traditional referral to a specialist clinical psychosis centre, might detect more ultra-high-risk (UHR) patients. This type of screening could be implemented in mental health care as routine screening. The trial is registered at Current Controlled trials as trial number ISRCTN21353122.


Psychiatry Research-neuroimaging | 2013

Depression and social anxiety in help-seeking patients with an ultra- high risk for developing psychosis

Judith Rietdijk; Helga K. Ising; Sara Dragt; Rianne Klaassen; Dorien H. Nieman; Lex Wunderink; Pim Cuijpers; Don Linszen; Mark van der Gaag

Knowledge on associations between ultra-high risk (UHR) for developing psychosis and on non-psychotic psychopathology in help-seeking populations is limited with respect to differences between male and female patients. The present study tests the hypothesis that both social anxiety and depression are highly prevalent in an UHR population, particularly among women. From February 2008 to February 2010 baseline data were collected from help-seeking subjects (14-35 years) who were included in the Dutch Early Detection and Intervention Evaluation (EDIE-NL) trial. Two recruiting strategies were used: a two-stage screening strategy in a population of consecutive help-seeking and distressed subjects of secondary mental health services, and a referral strategy. This study included 201 patients with a mean age of 22.7 years. Of these, 102 (51%) were female, 58% of the patients met the criteria for clinical depression on the Beck Depression Inventory and 42% met the criteria for clinical social phobia on the Social Interaction Anxiety Scale. Women showed more depression and social anxiety than men. The results support the hypothesis that UHR is associated with depression and social anxiety, particularly in women. Screening a help-seeking population with depression and anxiety may be effective in detecting patients at UHR for developing psychosis.


Psychopathology | 2011

Factor analysis of the scale of prodromal symptoms: Differentiating between negative and depression symptoms.

Rianne Klaassen; Dorien H. Nieman; Lieuwe de Haan; Hiske E. Becker; Peter Dingemans; J. Reinaud van de Fliert; Mark van der Gaag; Don Linszen

Background: This study examines the ability of the Scale of Prodromal Symptoms (SOPS) to differentiate between negative and depression symptoms in a young help-seeking ultrahigh risk (UHR) group. Methods: SOPS data of 77 help-seeking patients at UHR for psychosis were analyzed with an exploratory factor analysis. The extracted Depression factor was validated with the Beck Depression Inventory (BDI). The extracted SOPS Negative symptoms factor was validated with the Negative symptoms subscale of the Positive and Negative Syndrome Scale (PANSS). Results: Four factors were extracted from the SOPS: a negative, depression, disorganized and positive factor. The Negative symptom factor consisted of three items (N1: social anhedonia and withdrawal, N3: decreased expression of emotion; N4: decreased experience of emotions and self), and could be validated with the PANSS Negative symptoms subscale. The Depression factor was also made up of three items (G2: dysphoric mood, G4: impaired tolerance to normal stress, and D4: personal hygiene/social attentiveness), and could be validated with the BDI. Conclusions: Our results suggest that 3 items of the Negative symptoms subscale of the SOPS, 2 items of the General and 1 item of the Disorganization subscale differentiate validly between negative and depression symptoms in an UHR population.


Psychological Medicine | 2013

Depressive symptoms are associated with (sub)clinical psychotic symptoms in patients with non-affective psychotic disorder, siblings and healthy controls

Rianne Klaassen; Manuela Heins; L.B. Luteijn; M. van der Gaag; N. van Beveren; Richard Bruggeman; Wiepke Cahn; L. de Haan; R.S. Kahn; L. Krabbendam; D. Linzen; Inez Myin-Germeys; J. van Os; Diederik S. Wiersma

BACKGROUND Depression is a clinically relevant dimension, associated with both positive and negative symptoms, in patients with schizophrenia. However, in siblings it is unknown whether depression is associated with subclinical positive and negative symptoms. Method Depressive symptoms and their association with positive and negative symptoms were examined in 813 healthy siblings of patients with a non-affective psychotic disorder, 822 patients and 527 healthy controls. Depressive episodes meeting DSM-IV-TR criteria (lifetime) and depressed mood (lifetime) were assessed with the Comprehensive Assessment of Symptoms and History (CASH) in all three groups. In the patient group, the severity of positive and negative psychosis symptoms was assessed with the CASH. In the siblings and healthy controls, the severity of subclinical psychosis symptoms was assessed with the Community Assessment of Psychic Experiences (CAPE). RESULTS Patients reported more lifetime depressed mood and more depressive episodes than both siblings and controls. Siblings had a higher chance of meeting lifetime depressive episodes than the controls; no significant differences in depressed mood were found between siblings and controls. In all three groups the number and duration of depressive symptoms were associated with (sub)clinical negative symptoms. In the patients and siblings the number of depressive symptoms was furthermore associated with (sub)clinical positive symptoms. Finally, lifetime depressed mood showed familial clustering but this clustering was absent for lifetime depressive episodes. CONCLUSIONS These findings suggest that a co-occurring genetic vulnerability for both depressive and psychotic symptomatology exists on a clinical and a subclinical level.


Psychiatry Research-neuroimaging | 2017

The effect of childhood adversity on 4-year outcome in individuals at ultra high risk for psychosis in the Dutch Early Detection Intervention Evaluation (EDIE-NL) Trial

Tamar Kraan; Helga K. Ising; Marjolein Fokkema; David P. G. van den Berg; Margot Kerkhoven; Wim Veling; Filip Smit; Don Linszen; Dorien H. Nieman; Lex Wunderink; Nynke Boonstra; Rianne Klaassen; Sara Dragt; Judith Rietdijk; Lieuwe de Haan; Mark van der Gaag

Childhood adversity is associated with a range of mental disorders, functional impairment and higher health care costs in adulthood. In this study we evaluated if childhood adversity was predictive of adverse clinical and functional outcomes and health care costs in a sample of patients at ultra-high risk (UHR) for developing a psychosis. Structural Equation Modeling was used to examine the effect of childhood adversity on depression, anxiety, transition to psychosis and overall functioning at 4-year follow-up. In addition, we evaluated economic costs of childhood adversity in terms of health care use and productivity loss. Data pertain to 105 UHR participants of the Dutch Early Detection and Intervention Evaluation (EDIE-NL). Physical abuse was associated with higher depression rates (b=0.381, p=0.012) and lower social functional outcome (b=-0.219, p=0.017) at 4-year follow-up. In addition, emotional neglect was negatively associated with social functioning (b=-0.313, p=0.018). We did not find evidence that childhood adversity was associated with transition to psychosis, but the experience of childhood adversity was associated with excess health care costs at follow-up. The data indicate long-term negative effects of childhood adversity on depression, social functioning and health care costs at follow-up in a sample of UHR patients.

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Don Linszen

University of Amsterdam

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Sara Dragt

University of Amsterdam

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Nynke Boonstra

University Medical Center Groningen

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Wim Veling

University Medical Center Groningen

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Pim Cuijpers

Public Health Research Institute

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