Antipsychotic prescribing trends: a review of pharmaco-epidemiological studies

Effects of drop-out on efficacy estimates in five Cochrane reviews of popular antipsychotics for schizophrenia

OBJECTIVE

Our aim was to find out how Cochrane reviews of five popular or frequently prescribed second-generation antipsychotics in the UK (olanzapine, risperidone, quetiapine, amisulpride and aripiprazole) approached the problem of high drop-out in placebo-controlled trials.

METHOD

We examined the following: (i) whether reviews included data from studies with a level of drop-out exceeding their stated exclusion criterion; (ii) the level of missing data each efficacy outcome in each review relied upon; and (iii) impact of excluding studies with high drop-out.

RESULTS

All reviews included data they stated they would exclude because of unacceptable levels of attrition, four (risperidone, olanzapine, amisulpride, aripiprazole) without clear acknowledgement or justification. Several reviews also excluded data from a number of relatively low-attrition studies because of missing standard deviations.

CONCLUSION

Cochrane reviews of five popular antipsychotics for schizophrenia misrepresented the available evidence on their efficacy. The impact of including high-attrition studies was difficult to quantify because of the exclusion of relevant low-attrition studies. Further analysis of the efficacy of these drugs in studies with acceptable rates of attrition is required. To reduce the problem of high attrition, trialists should gather follow-up data from people who leave the double-blind process early.

The use of antipsychotics in a medium-long stay psychiatric hospital from 1998 to 2010

OBJECTIVE

Atypical agents have emerged as the dominant choice among antipsychotics. Data about development of antipsychotic use in medium-long stay psychiatric hospitals is lacking.

MATERIAL AND METHODS

Antipsychotic drug consumption data and cost was obtained from 1998 to 2010 for all inpatients of a 231-bed psychiatric hospital. Number of hospital stays was obtained from the hospital admission unit. Daily defined dose (DDD) values were those assigned by the WHO. Antipsychotic use was also measured using recently available consensus-based recommendations. Antipsychotic use was then calculated as the sum of individual DDD or total equivalent doses of all antipsychotics divided by the annual stay number.

RESULTS

Antipsychotic use increased 135% from 1998 to 2010 when measured in DDDs or 108% when measured with the consensus-based recommendations. Antipsychotic expenditure has risen six-fold since 1998. This augmentation is due to the increase of use of atypical antipsychotics.

CONCLUSION

In conclusion, antipsychotic use has at least doubled in the last 13 years. This growth, attributable to an increase in atypical drug use, has contributed to a six-fold increase in the total antipsychotic expenditure. Whether this prescription pattern has translated into palpable clinical benefits remains unclear.

Trends in prescriptions and costs of drugs for mental disorders in England, 1998-2010

BACKGROUND

Increasing rates of prescriptions for antidepressants, antipsychotics and stimulants have been reported from various countries.

AIMS

To examine trends in prescriptions and the costs of all classes of psychiatric medication in England.

METHOD

Data from the Prescription Cost Analysis 1998-2010 was examined, using linear regression analysis to examine trends.

RESULTS

Prescriptions of drugs used for mental disorders increased by 6.8% (95% CI 6.3-7.4) per year on average, in line with other drugs, but made up an increasing proportion of all prescription drug costs (P = 0.001). There were rising trends in prescriptions of all classes of psychiatric drugs, except anxiolytics and hypnotics (which did not change). Antidepressant prescriptions increased by 10% (95% CI 9.0-11) per year on average, and antipsychotics by 5.1% (95% CI 4.3-5.9). Antipsychotics overtook antidepressants as the most costly class of psychiatric medication, with costs rising 22% (95% CI 17-27) per year.

CONCLUSIONS

Rising prescriptions may be partly explained by longer-term treatment and increasing population. Nevertheless, it appears that psychiatric drugs make an increasing contribution to total prescription drug costs, with antipsychotics becoming the most costly. Low-dose prescribing of some antipsychotics is consistent with other evidence that their use may not be restricted to those with severe mental illness.

Extrapyramidal motor side-effects of first- and second-generation antipsychotic drugs

BACKGROUND

Second-generation antipsychotics have been thought to cause fewer extrapyramidal side-effects (EPS) than first-generation antipsychotics, but recent pragmatic trials have indicated equivalence.

AIMS

To determine whether second-generation antipsychotics had better outcomes in terms of EPS than first-generation drugs.

METHOD

We conducted an intention-to-treat, secondary analysis of data from an earlier randomised controlled trial (n = 227). A clinically significant difference was defined as double or half the symptoms in groups prescribed first- v. second-generation antipsychotics, represented by odds ratios greater than 2.0 (indicating advantage for first-generation drugs) or less than 0.5 (indicating advantage for the newer drugs). We also examined EPS in terms of symptoms emergent at 12 weeks and 52 weeks, and symptoms that had resolved at these time points.

RESULTS

At baseline those randomised to the first-generation antipsychotic group (n = 118) had similar EPS to the second-generation group (n = 109). Indications of resolved Parkinsonism (OR = 0.5) and akathisia (OR = 0.4) and increased tardive dyskinesia (OR = 2.2) in the second-generation drug group at 12 weeks were not statistically significant and the effects were not present by 52 weeks. Patients in the second-generation group were dramatically (30-fold) less likely to be prescribed adjunctive anticholinergic medication, despite equivalence in terms of EPS.

CONCLUSIONS

The expected improvement in EPS profiles for participants randomised to second-generation drugs was not found; the prognosis over 1 year of those in the first-generation arm was no worse in these terms. The place of careful prescription of first-generation drugs in contemporary practice remains to be defined, potentially improving clinical effectiveness and avoiding life-shortening metabolic disturbances in some patients currently treated with the narrow range of second-generation antipsychotics used in routine practice. This has educational implications because a generation of psychiatrists now has little or no experience with first-generation antipsychotic prescription.

Effects of polypharmacy on outcome in patients with schizophrenia in routine psychiatric treatment

OBJECTIVE

Evaluating the effects of different types of psychotropic polypharmacy on clinical outcomes and quality of life (QOL) in 374 patients with schizophrenia and schizoaffective disorder in routine care.

METHOD

Psychotropic regimen, clinical outcomes, and QOL were assessed before discharge and after 6, 12, 18, and 24 months. Data were analyzed by mixed-effects regression models for longitudinal data controlling for selection bias by means of propensity scores.

RESULTS

At baseline 22% of participants received antipsychotic monotherapy (APM) (quetiapine, olanzapine, or risperidone), 20% more than one antipsychotic drug, 16% received antipsychotics combined with antidepressants, 16% antipsychotics plus benzodiazepines, 11.5% had antipsychotics and mood stabilizers, and 16% psychotropic drugs from three or more subclasses. Patients receiving APM had better clinical characteristics and QOL at baseline. Patients receiving i) antipsychotics plus benzodiazepines or ii) antipsychotics plus drugs from at least two additional psychotropic drug categories improved less than patients with APM.

CONCLUSION

Combinations of antipsychotics with other psychotropic drugs seem to be effective in special indications. Nevertheless, combinations with benzodiazepines and with compounds from multiple drug classes should be critically reviewed. It is unclear whether poorer outcomes in patients with such treatment are its result or its cause.

Prescribing trends in bipolar disorder: cohort study in the United Kingdom THIN primary care database 1995-2009

OBJECTIVES

To determine changes in prescribing patterns in primary care of antipsychotic and mood stabiliser medication in a representative sample of patients with bipolar disorder in the United Kingdom over a fifteen year period and association with socio-demographic factors.

METHODS

We identified 4700 patients in the Health Improvement Network (THIN) primary care database, who had received treatment for bipolar disorder between 1995 and 2009. The proportion of time for which each individual was prescribed a particular medication was studied, along with variation by sex, age and social depravation status (quintiles of Townsend scores). The number of drugs an individual was taking within a particular year was also examined.

RESULTS

In 1995, 40.6% of patients with bipolar disorder were prescribed a psychotropic medication at least twice. By 2009 this had increased to 78.5% of patients. Valproate registered with the greatest increase in use (22.7%) followed by olanzapine (15.7%) and quetiapine (9.9%). There were differences by age and sex; with young (18-30 year old) women having the biggest increase in proportion of time on medication. There were no differences by social deprivation status. By 2009, 34.2% of women of childbearing age were treated with valproate.

CONCLUSIONS

Lithium use overall remained relatively constant, whilst second generation antipsychotic and valproate use increased dramatically. Changes in prescribing practice preceded published trial evidence, especially with the use of second generation antipsychotics, perhaps with inferences being made from treatment of schizophrenia and use of first generation antipsychotics. Women of childbearing age were prescribed valproate frequently, against best advice.

Are commonly used psychoactive medications associated with lower urinary tract symptoms?

PURPOSE

Lower urinary tract symptoms (LUTS) such as urinary frequency and urgency are bothersome and associated with reduced quality of life. Atypical antipsychotics (AAPs) have been implicated in increasing the risk of urinary incontinence. In a large community-based sample of men and women, we examined the associations of AAP and selective serotonin reuptake inhibitor (SSRIs) use with LUTS.

METHODS

Data were collected (2002-2005) from a generalizable sample of Boston, MA, USA, residents aged 30-79 (N = 5503). LUTS were assessed using the American Urologic Association Symptom Index (AUA-SI). The prevalence of clinically-significant LUTS was estimated using a cutoff AUA-SI score of 8+ to indicate moderate-to-severe symptoms. Confounder-adjusted odds ratios (ORs) and 95% confidence intervals (CI) were calculated from multivariate logistic regression to estimate the associations for psychoactive drugs used in the previous month (SSRIs, AAPs, both) and LUTS.

RESULTS

Among women, AAP users had a higher prevalence of LUTS (46.2%) compared with SSRI users (23.5%) and those with depressive symptoms not using SSRIs or AAPs (26.3%). Corresponding prevalence estimates among men were 32.7%, 29.8%, and 33.3%. In multivariate models, AAP use was significantly associated with LUTS among women when used either with (OR = 2.72, 95% CI:1.45-5.10) or without (OR = 3.05, 95% CI:1.30-7.16) SSRIs, but SSRI use without AAP use was not associated with LUTS compared with nonusers without depressive symptoms. No associations were observed among men.

CONCLUSIONS

In our study, AAPs but not SSRIs were associated with increased prevalence of LUTS among women only. Further prospective research is needed to determine time sequence and cause and effect.

Change in psychotropic drug use among community-dwelling people aged 75 years and older in Finland: repeated cross-sectional population studies

BACKGROUND

Older people are at high risk of experiencing psychotropic-related adverse drug events. The objective of this study was to compare and contrast the use of psychotropic drugs among community-dwelling people aged ≥ 75 years in 1998 and 2004.

METHODS

Comparable random samples of people aged ≥ 75 years were extracted from the population register in Kuopio, Finland, in 1998 (n = 700) and 2003 (n = 1000). In 1998 and 2004, 523 and 700 community-dwelling people respectively participated in nurse interviews, during which demographic, diagnostic and drug use data were elicited. Logistic regression was used to compute unadjusted and adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for the prevalence of psychotropic drug use in 2004 compared to 1998.

RESULTS

The unadjusted prevalence of total psychotropic (37.3% and 38.4%, OR 1.05; 95% CI 0.83-1.33), anxiolytic, hypnotic and sedative (29.6% and 31.3%, OR 1.08, 95% CI 0.85-1.38), and antidepressant (10.7% and 11.9%, OR 1.12, 95% CI 0.78-1.61) use were similar in 1998 and 2004. There was a decrease in the unadjusted prevalence of antipsychotic use (9.2% and 5.7%, OR 0.60; 95% CI 0.39-0.93). After adjusting for socioeconomic and health status differences, there was an increase in the prevalence of total psychotropic (adjusted OR 1.31, 95% CI 1.01-1.70) and antidepressant (OR 1.59, 95% CI 1.06-2.40) use.

CONCLUSION

The unadjusted prevalence of psychotropic drug use remained stable between 1998 and 2004. However, in adjusted analyses there was a small increase in the prevalence of any psychotropic drug use and antidepressant use specifically.

National changes in oral antipsychotic treatment for people with schizophrenia in primary care between 1998 and 2007 in the United Kingdom

PURPOSE

There is little information regarding antipsychotic prescription in primary care, despite general practitioners issuing most ongoing prescriptions. We sought to investigate changes in oral antipsychotic prescriptions in primary care from January 1998 to December 2007.

METHODS

We conducted a cohort analysis of patients diagnosed with schizophrenia in primary care in the United Kingdom, using The Health Improvement Network database, to determine the proportions of prescribed antipsychotics. We investigated the yearly estimates of the overall time patients spent in treatment with any antipsychotic as well as the class of antipsychotic and individual antipsychotic agent.

RESULTS

We found that in any one calendar year, approximately 24% of patients previously prescribed antipsychotics do not receive treatment in primary care. Over the last decade, people with schizophrenia have been prescribed antipsychotic treatment for greater proportions of time. The greatest increase was observed in older women. The overall increase in treatment time can be attributed to the increased prescription of second-generation antipsychotics (SGAs). The annual proportion of time in SGA treatment increased from 16.6% to 51.2% within the study period, whereas time in first-generation antipsychotic treatment reduced from 37.1% to 15.0%. Overall, olanzapine, risperidone and sulpiride were prescribed for the longest periods of time.

CONCLUSIONS

Over the last decade, the general practice of prescribing SGAs has increased whereas first-generation antipsychotic prescriptions have declined. By 2007, patients with schizophrenia were prescribed antipsychotics for greater proportions of time, perhaps reflecting the greater acceptability of SGAs or a shift from secondary to primary care prescription.

Second generation antipsychotics (SGAs) for non-psychotic disorders in children and adolescents: a review of the randomized controlled studies

In children and adolescents the Second Generation Antipsychotics (SGAs) represent the class of psychotropic drugs whose use has grown more significantly in recent years: they are primarily used for treatment of patients with disruptive behavior disorders, mood disorders and pervasive developmental disorders or mental retardation. In order to compare the efficacy and tolerability of antipsychotics against placebo or each other, a systematic Medline/PubMed search for randomized, double blind studies on SGA in patients younger than 18 years of age at enrollment, was conducted. Papers on schizophrenia, discussed in another article of this specific issue, were excluded by the efficacy analysis. A set of standard efficacy and safety indices, such as treatment effect sizes (ES), the Numbers Needed to Treat (NNT) and Numbers Needed to Harm (NNH), was used to compare medications. 32 studies analyzing efficacy and/or tolerability of SGAs in children and adolescents with bipolar, autistic or disruptive behavior disorders, and Tourette syndrome were identified. SGAs efficacy on mania, extreme mood variability, irritability, aggression and disruptive behavior appears to be greater than for psychotic symptoms in schizophrenia: average NNT was 2-5, whereas for schizophrenia it varies between 3 for risperidone and 10 for olanzapine, quetiapine, and aripiprazole. As for schizophrenia, different SGAs show a similar efficacy for specific non-psychotic disorders, but they significantly differ in their safety profile. In randomized studies, adverse effects were usually relatively minor, easily predictable and manageable, whereas long-term open-label studies have indicated that some adverse event, such as the metabolic effects, may be severe and potentially life threatening on the long-term. Taken together, these findings suggest that the choice of a specific treatment should be guided primarily by the safety profile of specific antipsychotics, considering specific risk factors (i.e. obesity and BMI, family history of diabetes or cardiovascular disorder, etc) for the single patient.

What happened to the voices? A fine-grained analysis of how hallucinations and delusions change under psychiatric treatment

The Psychiatric Symptom Rating Scales (PSYRATS) have demonstrated their usefulness for the dimensional assessment of hallucinations and delusions. However, there is no evaluated German version of the PSYRATS to date. Also, in spite of theoretical conceptions about "detaching" effects of antipsychotics, there are few consolidated findings about how core symptomatic aspects of schizophrenia change during antipsychotic treatment. The present study aimed to fill this gap. A total of 40 schizophrenic voice-hearers were interviewed three times during the course of six months using a newly developed German version of the PSYRATS with very good psychometric properties. At the same time, psychopathology was assessed with the Positive and Negative Syndrome Scale (PANSS). In the longitudinal course, a general symptomatic decrease became apparent only for auditory hallucinations but not for delusions. Specifically, the loudness of the hallucinated voices as well as the associated distress decreased early, while other aspects of the hallucinations took more time to fade. In this study, the PSYRATS proved to be a valuable tool for measuring the change of specific symptom dimensions. However, our results only partially supported the notion of a general detachment from symptoms due to psychiatric treatment.

Initial prescription of antipsychotics and antidepressants in general practice and specialist care in Norway

OBJECTIVE

To examine the incidence rates of antipsychotic (AP) and antidepressant (AD) drug treatment in Norway and the proportions initiated in general practice and specialist care respectively.

METHOD

Data on all prescriptions of APs and ADs dispensed to the general population in Norway from 1 January 2004 until 31 August 2009 were extracted from the Norwegian Prescription Database. This information was merged with data about general practitioners (GPs) from the Norwegian Regular General Practitioner Scheme.

RESULTS

One-year incidence rates per 1000 inhabitants were 3.4 for APs and 8.6 for ADs. GPs initiated 58% of APs and 73% of ADs, while psychiatrists initiated 15% and 6% respectively. Psychiatrists initiated treatment more often among younger patients, and they prescribed relatively newer drugs more commonly than GPs. A large share of incident users did not refill their prescriptions for APs (57%) or ADs (33%).

CONCLUSION

GPs have a key role as regards initiating treatment with APs and ADs in Norway, while psychiatrists' influence seems limited, particularly among older patients. Efforts for quality improvement of mental health care need to involve primary health care. In addition, an increased focus from psychiatrists towards the increasingly ageing part of the population seems requisite.

Oral health of psychiatric inpatients: a survey of central Taiwan hospitals

OBJECTIVE

The objective was to investigate the status of oral health and its determinants in a group of psychiatric inpatients in central Taiwan.

METHOD

A cross-sectional study of the oral health of psychiatric inpatients (n=200) in three hospitals in central Taiwan was carried out during a half-year period. Demographic data and data on oral health habits, dental visit frequency, treatment fear and dental health knowledge were collected. Oral health was determined by the Decayed/Missing/Filled Teeth (DMFT) index, Community Periodontal Index (CPI), Plaque Index and Gingival Index.

RESULTS

In terms of prevalence of caries, the mean DMFT score for all patients was 14.9 ± 8.8 (S.D.), which was significantly worse than that in the general population. The CPI showed that only 10% of patients were periodontally healthy, 9.5% had bleeding, 31% had calculus and 49.5% had periodontal pockets. Increasing age, treatment anxiety, neglect of tooth-brushing and chronic ward inpatients were predictive factors for poor periodontal health. The self-awareness of poor oral health was inadequate and the treatment needs were huge in psychiatric inpatients.

CONCLUSION

The oral health of psychiatric inpatients was poor compared with the general population and was generally ignored by the patients themselves. The phenomenon is universal, occurring in both Western and Eastern countries.

Characterisation of zuclopenthixol metabolism by in vitro and therapeutic drug monitoring studies

OBJECTIVE

Zuclopenthixol pharmacokinetics is incompletely characterised. We investigated potential interactions mediated through cytochrome P450 enzymes.

METHOD

In vitro, we examined the impact of CYP2D6 and CYP3A4 inhibitors on zuclopenthixol metabolism in microsomes from six human livers. Subsequently, we compared dose-corrected serum zuclopenthixol concentrations in 923 samples from a therapeutic drug monitoring database from patients prescribed oral (n = 490) or injected (n = 423) zuclopenthixol alone or with fluoxetine, paroxetine, levomepromazine or carbamazepine.

RESULTS

In vitro fluoxetine, paroxetine, ketoconazole and quinidine all significantly inhibited zuclopenthixol metabolism. Ketoconazole and quinidine together abolished zuclopenthixol disappearance. Clinically, dose-corrected oral zuclopenthixol serum concentrations increased significantly, after adjustment, by 93%, 78% and 46% during co-treatment with fluoxetine, paroxetine and levomepromazine and decreased 67% with carbamazepine. Carbamazepine caused dose-dependent reductions in the oral zuclopenthixol concentration-dose ratio (P < 0.001), fluoxetine (P < 0.001) and paroxetine (P = 0.011) dose-dependent increases and levomepromazine an increase related to its serum concentration (P < 0.001). Results for injected zuclopenthixol were similar but not all reached statistical significance.

CONCLUSION

The In vitro study suggests zuclopenthixol is metabolised primarily by CYP2D6 and CYP3A4. The clinical study supports this, demonstrating the impact of co-prescribed inhibitors or inducers. Guidelines should incorporate these interactions noting the potential for zuclopenthixol-related toxicity or treatment failure.

10-year trends in the treatment and outcomes of patients with first-episode schizophrenia

OBJECTIVE

The first episode of schizophrenia is a critical period for illness course and outcomes. We aimed to investigate treatments and outcomes during the first year after the diagnosis of schizophrenia.

METHOD

Pharmacoepidemiologic inception cohort study of all newly diagnosed patients with schizophrenia in Denmark (n = 13,600) 1996-2005.

RESULTS

From 1996 to 2005, the mean age at first diagnosis decreased significantly (29.2-26.1 years), more patients received antipsychotics (67.2-80.7%, annual OR = 1.07, CI: 1.06-1.09, P < 0.001) and antipsychotic polypharmacy for >4 months (16.7-37.1%, OR = 1.14, CI: 1.12-1.57, P < 0.001). The antipsychotic defined daily dosage (DDD) doubled (150-332 DDD, P < 0.001), use of antidepressants (24.3-40.6%, P < 0.001). Bed days [89.9 days (CI: 81.8-98.8) to 71.8 days, CI: 63.7-80.8, P < 0.0001] decreased, whereas outpatient contacts [10.2 (CI: 9.5-11.0) to 21.4 (CI: 19.9-21.0), P < 0.0001] doubled.

CONCLUSION

Between 1996 and 2005, there was an earlier recognition of schizophrenia, intensified outpatient treatment, increased use and dosing of antipsychotics and antidepressants, but also more antipsychotic polypharmacy.