The temporal relationship between symptom change and treatment discontinuation in a pooled analysis of 4 schizophrenia trials

Adherence to Antipsychotic Medication and Criminal Recidivism in a Canadian Provincial Offender Population

Preliminary evidence suggests that adherence to antipsychotic medication reduces criminal recidivism among patients diagnosed with schizophrenia. However, existing studies operationalize antipsychotic adherence as a binary variable (usually using a threshold of ≥80%), which does not reflect the prevalence of suboptimal adherence in real-world settings. The purpose of the current analysis was to investigate the association between successive ordinal levels of antipsychotic adherence and criminal recidivism in a well-defined sample of offenders diagnosed with schizophrenia (n = 11462). Adherence was measured using the medication possession ratio (MPR) and analyzed as a time-dependent covariate in multivariable regression models. Data were drawn from linked, comprehensive diagnostic, pharmacy and justice system records, and individuals were followed for an average of 10 years. Adjusted rate ratios (ARR) and confidence intervals (CI) are reported. Overall mean MPR was 0.41. Increasing levels of antipsychotic adherence were not associated with progressively lower rates of offending. However, when compared to the reference group (MPR ≥ 80%) all lower adherence levels were significantly associated (P < .001) with increased risk of violent (ARR = 1.58; 95% CI = 1.46-1.71) and nonviolent (ARR = 1.41; 95% CI = 1.33-1.50) offenses. Significance was replicated in separate sensitivity analyses. Previously published studies reporting reductions in crime may have been influenced by antipsychotic adherence ≥80%. Binary operationalization of adherence is an inaccurate predictor of recidivism. Future research addressing functional outcomes of antipsychotic adherence should conceptualize adherence as an incremental independent variable.

Clinical predictors of therapeutic response to antipsychotics in schizophrenia

The search for clinical outcome predictors for schizophrenia is as old as the field of psychiatry. However, despite a wealth of large, longitudinal studies into prognostic factors, only very few clinically useful outcome predictors have been identified. The goal of future treatment is to either affect modifiable risk factors, or use nonmodifiable factors to parse patients into therapeutically meaningful subgroups. Most clinical outcome predictors are nonspecific and/or nonmodifiable. Nonmodifiable predictors for poor odds of remission include male sex, younger age at disease onset, poor premorbid adjustment, and severe baseline psychopathology. Modifiable risk factors for poor therapeutic outcomes that clinicians can act upon include longer duration of untreated illness, nonadherence to antipsychotics, comorbidities (especially substance-use disorders), lack of early antipsychotic response, and lack of improvement with non-clozapine antipsychotics, predicting clozapine response. It is hoped that this limited capacity for prediction will improve as pathophysiological understanding increases and/or new treatments for specific aspects of schizophrenia become available.

Reasons for adherence and nonadherence: a pilot study comparing first- and multi-episode schizophrenia patients

RATIONALE

Most first-episode schizophrenia patients will stop their medication after their acute symptoms improve. Understanding the salient motivations and attitudes that drive adherence--as well as nonadherence--is an important part of developing strategies to prevent or delay nonadherence during the early phases of the illness.

METHODS

Self-reported reasons for adherence and nonadherence among first-episode and multi-episode patients with schizophrenia were obtained from cross-sectional adherence interviews from two prospective adherence studies: one composed of a first-episode sample (n=33) and the other with recently relapsing multi-episode patients (n=16). Both groups received the Rating of Medication Influences (ROMI) Scale at approximately 16 to 20 weeks after an acute psychotic episode. The specific ROMI items were ranked in order of percentage (%) strong, and were compared both within each patient group for rank order of importance, and also compared between groups to determine the differences in specific adherence and nonadherence influences.

RESULTS

The doctor-patient relationship was more likely to be endorsed as a strong adherence influence in the first-episode sample (74%) than in the multi-episode sample (13%, X²=18.07, p<.01). Change in physical appearance attributed to medication was a more commonly endorsed nonadherence influence for the multi-episode sample (25%) relative to the first-episode sample (0%, X²=9.2, p<.01).

CONCLUSIONS

The doctor-patient relationship stands out as being the major reason for ongoing adherence for first-episode schizophrenia patients. Our post hoc interpretation is that lack of prior experience with medication and treatment elevates the importance of the relationship with the treating clinician for first-episode patients.

A composite scale applied to evaluate anxiety in schizophrenic patients (SAES)

Anxiety in schizophrenia possesses specific features and is difficult to assess because no specific evaluating tool is currently available. The aim of this study was to develop and validate a hetero-assessment-based scale to specifically measure anxiety in schizophrenia. A literature review and a survey among psychiatrists allowed the selection of 29 items from 4 previous scales evaluating anxiety. Factor analysis allowed building up a final 22-item composite scale of anxiety evaluation in schizophrenia (SAES), which was then validated in 147 schizophrenic patients. One hundred and forty-seven (147) schizophrenic patients (70.8 % male, mean age = 36.9 years) were included in the study. Principal component analysis of the SAES revealed three factors, namely "expressed and perceived anxiety," "somatic anxiety," and "anxiety and environment". All total and factor scores of the SAES were significantly correlated (p < .001) with total and factor scores of the original scales. Finally, the SAES showed good inter-rater reliability [intra-class correlation coefficient (ICC) = .82]. In conclusion, a specific tool for evaluating anxiety in schizophrenia (SAES) was developed and validated in a sample of schizophrenic patients. The SAES can be useful to investigate clinical, psychopathological, and therapeutic aspects of anxiety in schizophrenia.

Does early improvement predict response to the fast-dissociating D₂ receptor antagonist JNJ-37822681 in patients with acute schizophrenia?

Early predictability of sustained response to atypical antipsychotics in patients with schizophrenia has important implications for clinical decision making. In order to investigate whether early onset of efficacy correlates with week-6 response for the selective fast-dissociating D2 receptor antagonist JNJ-37822681, we analysed data from a 12-week placebo- and active-controlled (olanzapine) study designed to evaluate efficacy and safety of JNJ-37822681. Factors, including baseline Positive and Negative Syndrome Scale (PANSS) total score, waist circumference, weight, body mass index group, number of previous hospitalisations, age at diagnosis, race, sex and age at study entry, and relative (%) change from baseline on day 3 (early improvement) in PANSS total score, were analysed using logistic regression models and receiver operator characteristic (ROC) curve analysis, to predict the week-6 efficacy response (≥ 30% improvement in PANSS total score). Results showed that week-6 response with JNJ-37822681 30 mg bid treatment could be reliably predicted by improvement in PANSS total score on day 3, the number of previous hospitalisations, and race (80% accuracy [ROC area under curve]). Early improvement (day 3) in PANSS score had the highest predictive value as a single factor across all JNJ-37822681 doses. At a specificity of 70%, sensitivity for predicting week-6 response was: 0.60, 0.64, and 0.74 in the 10-, 20-, and 30 mg bid JNJ-37822681 groups, respectively; 0.40 in olanzapine group. Early improvement in PANSS may be a simple and reliable way to predict sustained response with JNJ-37822681 in patients with acute schizophrenia.

Validation of a clinician questionnaire to assess reasons for antipsychotic discontinuation and continuation among patients with schizophrenia

The Reasons for Antipsychotic Discontinuation Questionnaire (RAD-Q) was designed to assess clinicians' perceptions of reasons for antipsychotic discontinuation or continuation. The current study examined psychometric properties of this instrument and patterns of antipsychotic discontinuation. The sample of 121 patients (81 discontinuation, 40 continuation) with schizophrenia or schizoaffective disorder was 66.9% male, with a mean age of 41.6 years. Treating clinicians reported a mean of 4.1 reasons for discontinuation and 7.5 reasons for continuation. RAD-Q domain scores were derived to quantify the impact of three factors on the decision to discontinue or continue: treatment benefits, adverse events, and distal reasons other than direct effects of the medication. Analysis of inter-rater reliability indicated an acceptable degree of agreement between clinicians (weighted Kappa for discontinuation scores=0.70-0.78). Correlations with symptom measures (Clinical Global Impression-Schizophrenia Scale (CGI-SCH), Positive and Negative Syndrome Scale (PANSS)) supported convergent validity of the benefits domain score (r=0.28-0.47; all p<0.05). Domain scores discriminated among groups of patients differing in clinician and patient-reported clinical variables. Results suggest that the RAD-Q is a useful detailed measure of reasons for antipsychotic discontinuation and continuation. Findings indicate that clinicians usually report multiple reasons for discontinuation, rather than a single reason for each patient.

Construct validity of 2 measures to assess reasons for antipsychotic discontinuation and continuation from patients' and clinicians' perspectives in a clinical trial

BACKGROUND

Little is known about the specific reasons for antipsychotic discontinuation or continuation from patients' or clinicians' perspectives. This study aimed to assess the construct validity of 2 new measures of the Reasons for Antipsychotic Discontinuation/Continuation (RAD): RAD-I (a structured interview assessing the patient's perspective) and RAD-Q (a questionnaire assessing the clinician's perspective).

METHODS

Data were used from a 12-week antipsychotic trial of schizophrenia patients in which the RAD was administered at study entry and at study completion (or discontinuation). Construct validity was assessed through comparisons of RAD responses, clinicians' responses to a standard patient disposition form identifying reasons for patient's study discontinuation, and several standard psychiatric measures. Percent agreement quantified the correspondence between patient and clinician scores.

RESULTS

Patients indicating lack of improvement/worsening of positive symptoms as a 'somewhat' to 'primary' reason for medication discontinuation had statistically significantly less improvement in Positive and Negative Syndrome Scale positive score than patients not reporting these as a reason (concurrent validity). Similar results were observed for the RAD negative symptom, functional, social support, and adherence items, whereas the mood and cognitive items were not significantly associated with change scores on standard psychiatric measures. Responses to the RAD were also weakly associated with variables that theoretically should not be related to them (divergent validity). Level of agreement between the clinician- and patient-rated RAD scores was high (60%-100%).

CONCLUSIONS

Initial validation of the RAD suggests that the instruments are valid tools for gathering detailed information regarding reasons for antipsychotic discontinuation and continuation from patients' and clinicians' perspectives.

Impact of symptom resolution on medication adherence in first episode psychosis

Adequate adherence to medication confers benefits on patients with psychotic illness, but is difficult to achieve. Efficacy of medication influences adherence in patients in advanced phases of illness and may have a similar influence on patients with a first episode of psychosis (FEP). We assessed medication adherence and efficacy in 216 FEP patients at program entry and at 3 and 6 months later. "Efficacy" was evaluated as the ability of medication to reduce positive or negative symptoms to below established thresholds for clinical remission at each evaluation. Adherence was defined as adequate (>75%) or not. Resolution of negative symptoms by month 3 of treatment was associated with inadequate adherence at months 3 and 6. In contrast, rapid resolution of positive symptoms showed no relationship to adherence. In a multivariate analysis taking into account other determinants of adherence in FEP, the role of early negative symptom remission was confirmed, and we found that a 3-month sustained remission of positive symptoms was associated with adequate adherence. Medication efficacy may promote adherence if it produces sustained remission of positive symptoms. However, many patients who benefit from medication, particularly those with rapid improvement of negative symptoms, fail to adhere to the treatment.

Validation of a patient interview for assessing reasons for antipsychotic discontinuation and continuation

INTRODUCTION

The Reasons for Antipsychotic Discontinuation Interview (RAD-I) was developed to assess patients' perceptions of reasons for discontinuing or continuing an antipsychotic. The current study examined reliability and validity of domain scores representing three factors contributing to these treatment decisions: treatment benefits, adverse events, and distal reasons other than direct effects of the medication.

METHODS

Data were collected from patients with schizophrenia or schizoaffective disorder and their treating clinicians. For approximately 25% of patients, a second rater completed the RAD-I for assessment of inter-rater reliability.

RESULTS

All patients (n = 121; 81 discontinuation, 40 continuation) reported at least one reason for discontinuation or continuation (mean = 2.8 reasons for discontinuation; 3.4 for continuation). Inter-rater reliability was supported (kappas = 0.63-1.0). Validity of the discontinuation domain scores was supported by associations with symptom measures (the Positive and Negative Syndrome Scale for Schizophrenia, the Clinical Global Impression - Schizophrenia Scale; r = 0.30 to 0.51; all P < 0.01), patients' primary reasons for discontinuation, and adverse events. However, the continuation domain scores were not significantly associated with these other indicators.

DISCUSSION

Results support the reliability, convergent validity, and known-groups validity of the RAD-I for assessing patients' reasons for antipsychotic discontinuation. Further research is needed to examine validity of the RAD-I continuation section.

Factors associated with adherence to treatment with olanzapine and other atypical antipsychotic medications in patients with schizophrenia

OBJECTIVES

Poor treatment response is an important factor contributing to lack of treatment adherence. The goals of this research were to determine whether improvements in Positive and Negative Syndrome Scale (PANSS) symptom domains predict the likelihood of staying on treatment and whether differential responses to treatment with various atypical antipsychotics in specific symptom domains account for differences in discontinuation rates or treatment adherence.

METHODS

We conducted a post-hoc analysis of pooled data from 5 randomized, double-blind, 24- to 28-week clinical trials in 1103 olanzapine-treated and 1090 risperidone-, quetiapine-, ziprasidone-, or aripiprazole-treated adult patients with schizophrenia. The 5 PANSS factors were tested as potential predictors of treatment adherence for all treatment groups combined. Treatment differences in the 5 PANSS factors and individual items were assessed between olanzapine and the other atypical antipsychotics combined. Secondary analyses repeated for the 21 Heinrichs Quality of Life Scale (QLS) items.

RESULTS

Improvement in PANSS positive factor was the strongest predictor of treatment adherence, irrespective of medication (based on standardized scores, hazard ratio [HR], 1.58; 95% confidence interval [CI], +1.40 to +1.79; P < .001). Improvement in PANSS hostility (HR, 1.23; 95% CI, +1.11 to +1.37; P < .001) and depressive (HR, 1.15; 95% CI, +1.05 to +1.27; P = .002) factors was also a significant predictor; negative and disorganized thoughts factors were not. All QLS items had significant predictive effects. Olanzapine-treated patients showed significantly greater improvements than all other groups at week 24 on all 5 PANSS factors (P = .028 for negative; P < .001 for all others) and on 3 QLS items.

CONCLUSION

Significant improvement in positive symptoms, regardless of treatment, followed by significant improvement in hostility and depressive symptoms, may best predict treatment adherence. Olanzapine-treated patients experienced significantly greater improvements in these specific symptoms than patients treated with the other atypical antipsychotics examined. These findings may further explain why olanzapine-treated patients continue treatment more often.

Identification of early changes in specific symptoms that predict longer-term response to atypical antipsychotics in the treatment of patients with schizophrenia

BACKGROUND

To identify a simple decision tree using early symptom change to predict response to atypical antipsychotic therapy in patients with (Diagnostic and Statistical Manual, Fourth Edition, Text Revised) chronic schizophrenia.

METHODS

Data were pooled from moderately to severely ill patients (n = 1494) from 6 randomized, double-blind trials (N = 2543). Response was defined as a ≥ 30% reduction in Positive and Negative Syndrome Scale (PANSS) Total score by Week 8 of treatment. Analyzed predictors were change in individual PANSS items at Weeks 1 and 2. A decision tree was constructed using classification and regression tree (CART) analysis to identify predictors that most effectively differentiated responders from non-responders.

RESULTS

A 2-branch, 6-item decision tree was created, producing 3 distinct groups. First branch criterion was a 2-point score decrease in at least 2 of 5 PANSS positive items (Week 2). Second branch criterion was a 2-point score decrease in the PANSS excitement item (Week 2). "Likely responders" met the first branch criteria; "likely non-responders" did not meet first or second criterion; "not predictable" patients did not meet the first but did meet the second criterion. Using this approach, response to treatment could be predicted in most patients (92%) with high positive predictive value (79%) and high negative predictive value (75%). Predictive findings were confirmed through analysis of data from 2 independent trials.

CONCLUSIONS

Using a data-driven approach, we identified decision rules using early change in the scores of selected PANSS items to accurately predict longer-term treatment response or non-response to atypical antipsychotic therapy. This could lead to development of a simple quantitative evaluation tool to help guide early treatment decisions.

TRIAL REGISTRATION

This is a retrospective, non-intervention study in which pooled results from 6 previously published reports were analyzed; thus, clinical trial registration is not required.

Patient perspectives on antipsychotic treatments and their association with clinical outcomes

This analysis examined patient-reported attitudes toward antipsychotic medication and the relationship of these attitudes with clinical outcomes and pharmacotherapy adherence. The analysis included three randomized, double-blind studies in patients with schizophrenia, schizoaffective disorder, or schizophreniform disorder diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders 4th Edition and randomly assigned to treatment with olanzapine 5-20 mg/day or another antipsychotic (haloperidol 2-20 mg/day, risperidone 2-10 mg/day, or ziprasidone 80-160 mg/day). Patient-reported improvements were significantly greater for olanzapine (n = 488) versus other treatments (haloperidol n = 145, risperidone n = 158, or ziprasidone n = 271) on multiple Drug Attitude Inventory items. A positive attitude toward medication reported by patients was significantly associated with greater clinical improvement on the Positive and Negative Syndrome Scale and lower discontinuation rates. These results suggest that patients' perceptions of treatment benefits are associated with objective clinical measures, including reduction of symptom severity and lower discontinuation rates. Furthermore, olanzapine may be associated with more positive treatment attitudes. These findings may contribute to a better understanding of reasons for treatment adherence from patients' own perspectives.

Predictors of switching antipsychotic medications in the treatment of schizophrenia

BACKGROUND

To identify patient characteristics and early changes in patients' clinical status that best predict subsequent switching of antipsychotic agents in the long-term treatment of schizophrenia.

METHODS

This post-hoc analysis used data from a one-year randomized, open-label, multisite study of antipsychotics in the treatment of schizophrenia. The study protocol permitted switching of antipsychotics when clinically warranted after the first eight weeks. Baseline patient characteristics were assessed using standard psychiatric measures and reviews of medical records. The prediction model included baseline sociodemographics, comorbid psychiatric and non-psychiatric conditions, body weight, clinical and functional variables, as well as change scores on standard efficacy and tolerability measures during the first two weeks of treatment. Cox proportional hazards modeling was used to identify the best predictors of switching from the initially assigned antipsychotic medication.

RESULTS

About one-third of patients (29.5%, 191/648) switched antipsychotics before the end of the one-year study. There were six variables identified as the best predictors of switching: lack of antipsychotic use in the prior year, pre-existing depression, female gender, lack of substance use disorder, worsening of akathisia (as measured by the Barnes Akathisia Scale), and worsening of symptoms of depression/anxiety (subscale score on the Positive and Negative Syndrome Scale) during the first two weeks of antipsychotic therapy.

CONCLUSIONS

Switching antipsychotics appears to be prevalent in the naturalistic treatment of schizophrenia and can be predicted by a small and distinct set of variables. Interestingly, worsening of anxiety and depressive symptoms and of akathisia following two weeks of treatment were among the more robust predictors of subsequent switching of antipsychotics.

Maintenance of response with atypical antipsychotics in the treatment of schizophrenia: a post-hoc analysis of 5 double-blind, randomized clinical trials

BACKGROUND

How long an antipsychotic is effective in maintaining response is important in choosing the correct treatment for people with schizophrenia. This post-hoc analysis describes maintenance of response over 24 or 28 weeks in people treated for schizophrenia with olanzapine, risperidone, quetiapine, ziprasidone, or aripiprazole.

METHODS

This was a post-hoc analysis using data from 5 double-blind, randomized, comparative trials of 24 or 28 weeks duration in which olanzapine was compared to risperidone (1 study; N = 339), quetiapine (1 study; N = 346), ziprasidone (2 studies; N = 548 and 394) or aripiprazole (1 study; N = 566) for treatment of schizophrenia. For each study, time to loss of response in patients who met criteria for response at Week 8 and the proportion of patients who lost response following Week 8 were compared by treatment group. The number needed to treat (NNT) with olanzapine rather than comparator to avoid loss of one additional responder over 24 or 28 weeks of treatment was calculated for each study.

RESULTS

Time maintained in response was significantly longer (p < .05) for olanzapine compared to risperidone, quetiapine, and ziprasidone. Olanzapine did not significantly differ from aripiprazole. The proportion of patients who lost response was significantly lower for olanzapine versus risperidone, quetiapine, and ziprasidone (p < .05). NNTs to avoid one additional patient with loss of response with olanzapine versus risperidone, quetiapine and ziprasidone were favourable, ranging from 5 to 9.

CONCLUSION

During 24 and 28 weeks of treatment, the antipsychotics studied differed in the time that treated patients with schizophrenia remained in response and the proportion of patients who lost response. Olanzapine treatment resulted in a consistent and statistically significant advantage in maintenance of response compared to treatment with risperidone, quetiapine and ziprasidone; but not compared to treatment with aripiprazole.