|Year : 2019 | Volume
| Issue : 3 | Page : 213-220
Correlates of Psychotropic Polypharmacy in outpatient psychiatric clinics of two military tertiary hospitals in Saudi Arabia
Fares F Alharbi1, Samar F Alharbi2, Saleh Bin Salih3, Khaled Al-Surimi4
1 King Abdullah International Medical Research Center; College of Medicine, King Saud bin Abdulaziz University for Health Sciences; Ministry of the National Guard Health Affairs, Riyadh, Saudi Arabia
2 Department of Pharmacy, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
3 King Abdullah International Medical Research Center; College of Medicine, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
4 Department of Health Systems Management, College of Public Health and Health Informatics, King Saud bin Abdulaziz University for Health Sciences, Ministry of the National Guard Health Affairs, Riyadh, Saudi Arabia; Department of Public Health, School of Public Health, Faculty of Medicine, Imperial College London, London, UK
|Date of Web Publication||11-Sep-2019|
Dr. Fares F Alharbi
College of Medicine, King Saud Bin Abdulaziz University for Health Sciences, P.O.Box: 3660, Riyadh 11481
Source of Support: None, Conflict of Interest: None
| Abstract|| |
BACKGROUND: Polypharmacy is meaningful and clinically justified under certain circumstances. However, the prescription of multiple psychiatric medicines is mostly based on practical experience rather than evidence. The aim of this study was to assess the current practice of and factors associated with the use of polypharmacy among patients attending outpatient psychiatric clinics.
MATERIALS AND METHODS: A cross-sectional study was conducted among patients attending outpatient psychiatric clinics in two tertiary care hospitals in the kingdom of Saudi Arabia (KSA). Patients aged 18 years and above and who were taking any prescription or nonprescription medications were included. Data were collected by face-to-face interviews, followed by a review of electronic medical charts to determine the drugs being taken by patients, and track their current computerized drug prescriptions. Data were analyzed using SPSS statistical software version 21 (Chicago, IL, USA), applying both descriptive and inferential statistical analysis as appropriate.
RESULTS: Of the 401 study participants, 53.6% were aged 25 years or older, and 63.6% were married and > 50% were unemployed. The overall prevalence of polypharmacy was 46.9%. The prevalence of polypharmacy was 67.3% in psychosis, 37.7% in depression, 27.1% in anxiety, 74.1% in bipolar disorders, and 53.6% for patients with two or more disorders, and 42.1% for patients diagnosed with “other” disorders. Overall, there was a significant association between polypharmacy and gender, marital status, and diagnosis of disorder.
CONCLUSIONS: Psychotropic polypharmacy is common in outpatient practice. Patients with psychosis and bipolar disorders, especially those aged 25–45 years are exposed to high psychotropic polypharmacy. The concomitant use of large numbers of drugs should be periodically reviewed to improve the quality and safety of psychiatric care.
Keywords: Bipolar disorder, drugs, medication, outpatients, polypharmacy, psychiatry, psychosis, Saudi Arabia
|How to cite this article:|
Alharbi FF, Alharbi SF, Salih SB, Al-Surimi K. Correlates of Psychotropic Polypharmacy in outpatient psychiatric clinics of two military tertiary hospitals in Saudi Arabia. J Fam Community Med 2019;26:213-20
|How to cite this URL:|
Alharbi FF, Alharbi SF, Salih SB, Al-Surimi K. Correlates of Psychotropic Polypharmacy in outpatient psychiatric clinics of two military tertiary hospitals in Saudi Arabia. J Fam Community Med [serial online] 2019 [cited 2019 Nov 17];26:213-20. Available from: http://www.jfcmonline.com/text.asp?2019/26/3/213/266597
| Introduction|| |
Psychiatric polypharmacy is defined as the prescription of multiple medications for the treatment of psychiatric conditions. The literature indicates that polypharmacy often commonly describes the use of five or more medications prescribed and used more often than is clinically indicated. The word “polypharmacy” was first used in an article discussing its occurrence at a mental hospital. Available research findings indicate that polypharmacy has become increasingly common in clinical psychiatric practice, and its use is driven more often by clinical experience than scientific evidence. It requires clinical knowledge, expertise, and a sound understanding of biological mechanisms underlying different symptoms, pharmacodynamics, and pharmacokinetic profiles of the drugs used a periodic check for their continued need and the pros and cons of the combination, and patient education to improve compliance. In many instances, polypharmacy may be unavoidable or necessary for patients with chronic illness. This is considered rational polypharmacy. In rational polypharmacy, the efficacy equation should be: 1 + 1 = 2 and the adverse effect equation: 1 + 1 = 1 or 0. However, irrational polypharmacy occurs too frequently: the efficacy equation 1 + 1 = 1 and the adverse effects 1 + 1 = 2.
In 1996 and 2006, Mojtabai and Olfson (2010) analyzed the National Ambulatory Medical Care Survey figures from office-based psychiatry practices in the United States. They found that the percentage of visits at which two or more psychotropic drugs were prescribed increased from 42.6% in 1996 to 59.8% in 2006, and those at which three or more psychotropic drugs were prescribed increased from 16.9% to 33.2%, respectively. A previous study reported the polypharmacy prevalence of about 21% in a Primary Health Care Center in Saudi Arabia. Other studies have also reported a very high prevalence of polypharmacy in adult outpatients at a Tertiary Care Center in Saudi Arabia.,
In the current practice, patterns of psychiatric medication prescription seem to have changed. Preskorn and Flockhart (2006) reported that the prescription of three or more medications on discharge from a psychiatric inpatient department increased from 5% in 1974 to 40% in 1995. Previous studies have also reported risk factors such as adverse drug/drug interactions, adverse effects, drug/disease interactions, inappropriate dosing, and higher cost related to polypharmacy in psychiatric care. For instance, in a survey of mental health patients (n = 2647), psychiatric polypharmacy was more common for men than women, and those aged between 25 and 45 years. In terms of multiclass polypharmacy, the most commonly prescribed combinations were found to be selective serotonin reuptake inhibitors (SSRIs) with a benzodiazepine, and tricyclic antidepressants (TCAs) with a benzodiazepine. The most common concurrently prescribed same-class medications were combinations of several benzodiazepines.,
When prescribing medication, patient safety is the main concern. Inappropriate polypharmacy can have negative effects, for instance, accumulative toxicity, high cost, drugs interactions, and drug-related adverse events. In addition, other drawbacks are lower patient compliance and adherence to multiple medications, which leads to more complex treatment regimen.
The use or prescription of more than one drug at a time is meaningful and clinically justified under certain circumstances. Polypharmacy may be helpful to target a wider number of symptoms, manage the same symptom by different mechanisms, treat comorbid conditions, common in psychiatry and neutralize side effects of one drug by another. However, the decision to prescribe multiple psychiatric medicines is mostly based on the practical experience rather than evidence and remains constrained by a lack of systematic research in this regard. Likewise, there are no reappraised evidence-based strategies to direct the practice of polypharmacy.
Overall, the history of medical practice indicates that in many instances, limited knowledge has led to certain practices that were later found to be unsuitable. More importantly, patterns of psychiatric prescription differ from one country to the next and are somewhat influenced by factors such as cost, availability of medicines, health-care policies, and desired treatment styles.
Until now, few published articles have discussed patterns of prescription for psychiatric patients in Middle Eastern countries. In Saudi Arabia, only one study, conducted in 1999, investigated the prescription of psychotropic drugs for patients attending outpatient psychiatric clinics in Al-Qassim. That study found that up to 85% of psychotic patients were given more than two drugs. Therefore, the primary goal of our study was to assess the current prevalence and factors associated with psychiatric polypharmacy for patients attending outpatient psychiatric clinics in two large tertiary hospitals in Saudi Arabia. The results of this study will help to improve the understanding of current practices and patterns and will provide empirical local evidence to inform policy and practices.
| Materials and Methods|| |
This cross-sectional study was conducted among patients attending outpatient psychiatric clinics at two tertiary care teaching hospitals in Saudi Arabia. The inclusion criteria were participants aged 18 years or older, taking two or more prescription or nonprescription medications to treat one or more conditions. Participants were excluded if they were not taking any medication, or if they were diagnosed with dementia, aggressive during the interview, or unable to give consent because of severe mental illness, and had no insight at the time of interview. Participants were recruited from March 2018 to December 2018.
The sample size of 235 participants was calculated using the freely available Raosoft software (http://www.raosoft.com/samplesize.html) and the following variables: expected 85% prevalence of psychiatric polypharmacy, statistical significance level of 95% (margin of error = 5%); and nonresponse rate of 20%.
Ethical approval from the Institutional Review Board/Ethics Committee had been obtained and informed written consent taken from all participants in the study. The participants' names were not recorded, and the data was kept confidential to protect the privacy of the participants. The data were not used for any purposes other than those stated in the study objectives. Targeted patients were recruited using a systematic random technique: the first patient was randomly selected after calculating the sampling interval by dividing the study population size by the calculated sample size, and then every odd number, the patient was taken until the required sample size was reached.
After receiving their informed consent, eligible patients who fulfilled the inclusion criteria were interviewed using a form specially designed for the study to obtain socio-demographic and relevant clinical information. This information included patients' hospital identification number, age, gender, education level, psychiatric diagnosis, the number of drugs being taken, the doses, and the number of prescription drugs. Data were collected by well-trained psychiatric residents in face-to-face interviews with the patients. Patients' electronic medical records were reviewed to confirm the diagnosis, drugs being taken by the patients, and the current computerized drug prescriptions. Patients were listed in the study only once; any duplicate follow-up forms were excluded from the final analysis.
Data were analyzed using IBM SPSS statistical software version 21 (Chicago, IL, USA). Descriptive statistics (frequency and percentages) were used to describe the categorical study and outcome variables. Pearson's Chi-square test was used to assess the association between the study variables and the binary outcome variable: polypharmacy (yes/no). Odds ratios were calculated to measure the strength of association. Multivariate binary stepwise logistic regression was used to determine any independent associations between polypharmacy and the study variables. The Hosmer and Lemeshow test was used to assess the fit. The model was validated using classification tables, and receiver operating curve analysis was used to assess the final model. A P ≤ 0.05 and a 95% confidence interval were used to report the statistical significance and precision of results.
| Results|| |
Of the 401 study participants, 53.6% were women aged 25 years or older, and 63.6% were married. The study subjects were evenly distributed in terms of educational status, and >50% were unemployed. About 75% of the participants were overweight (29.7%) or obese (44.9%) [Table 1]. The overall prevalence of polypharmacy for all patients was 46.9%. The prevalence of polypharmacy based on different types of medications and related classes was 67.3% for psychosis, 37.7% for depression, 27.1% for anxiety, 74.1% for bipolar disorders, 53.6% for patients with two or more disorders, and 42.1% for patients diagnosed with “other” disorders [Table 2].
|Table 2: Distribution of types of medications given to psychiatric patients by psychiatric diagnosis (multiple prescriptions)|
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[Table 3] shows the different types of antipsychotic, SSRI, serotonin, and norepinephrine reuptake inhibitor, TCA, mood stabilizer, sedative-hypnotic, and anticholinergic medications taken by patients with different psychiatric conditions. [Table 4] shows the number of different types of these medications prescribed to these patients at one sitting. The total number of medications prescribed to all these patients is shown in [Table 3] and [Table 4].
|Table 3: Distribution of medications of different classes given to psychiatric patients by psychiatric diagnosis|
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|Table 4: Distribution of the total number of different medications given to psychiatric patients by psychiatric diagnosis|
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Bivariate analysis indicated a statistically significant association between polypharmacy and gender, marital status, and diagnosis of disorder. The odds of polypharmacy were 1.48 times greater for men than for women (P = 0.043). In terms of marital status, the odds ratios showed that the prevalence of polypharmacy was higher for single (by 1.81 times) and the divorced (by 4.43 times) than for married persons (P = 0.002). A statistically significant association was found between polypharmacy for different psychiatric diagnoses. Out of six diagnosis categories, the odds of polypharmacy were 2.84 times and 3.93 times greater for psychosis and bipolar disorders, respectively, than for subjects diagnosed with other psychiatric disorders (P < 0.001). Age group, education level, occupation, and body mass index were not statistically significantly associated with polypharmacy [Table 5].
|Table 5: Factors associated with polypharmacy according to bivariate analysis (n=401)|
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However, multivariate binary stepwise logistic regression analysis indicated that age 26 years or older, being divorced, and diagnosed with psychosis or bipolar disorder was significantly associated with polypharmacy. Adjusted odds ratios and 95% confidence intervals are shown in [Table 6]. In this model, gender, education, occupation, and body mass index were not significantly associated with polypharmacy.
|Table 6: Independent factors associated with polypharmacy according to multivariate analysis using stepwise binary logistic regression|
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| Discussion|| |
The use of polypharmacy has become more common and is a major global concern because of the risk of adverse effects, poor medication, and higher medical costs.,, Polypharmacy may be defined as the concurrent use of multiple drugs that often suggests redundant use of medication., However, there is no consensus on the criteria for the definition of polypharmacy. Previous studies have defined polypharmacy as the concurrent use of at least two, three, or four medications. The World Health Organization suggests that the average number of medications per prescription is an important indicator of polypharmacy. Most European and Australian studies have defined polypharmacy as the simultaneous use of five or more medications.,,, In routine psychiatric clinical practice, patients are often prescribed a combination of medications, that is not supported by well-controlled clinical trials.,,,
The aim of the present study was to assess the current prevalence and predictors for the prescription of psychiatric polypharmacy for patients attending outpatient psychiatric clinics in two large tertiary hospitals in Saudi Arabia. The most common psychiatric disorder encountered in our study was depression, followed by psychosis and anxiety disorders. A previous study reported a significantly high (48.2%) prevalence of depressive symptoms in the Saudi population (Al-Faris et al., 2012), while another study found a slightly lower prevalence (16.2%).
Of the psychiatric patients included in the current study, about half were on polypharmacy. This finding is similar to the prevalence of polypharmacy reported in other studies: Salih et al. found a very high level of polypharmacy prescription in medical outpatients in Saudi Arabia; De las Cuevas and Sanz found that approximately half of their psychiatric patients were on polypharmacy; and Junius-Walker et al. (2007) reported that about 27% of patients at a German primary care center for older people were prescribed multiple drugs. In contrast, Grimmsmann and Himmel (2009) analyzed data from a large health insurance database and reported continuous polypharmacy for about 10% of German general practice patients. The reasons for this are not clear but may be attributed to the concomitant use of psychiatric drugs based on the experience rather than available evidence and research. Hence, there is a need for further studies about the prescription of various psychiatric drugs before any clinical recommendations are made.
Polypharmacy in psychiatry, combinations and/or augmentations, is most strongly correlated with the diagnosis, severity, chronicity, and the presence of comorbidities. This is common practice worldwide, although mostly based on experience rather than evidence-based. We found a significant association between the prevalence of polypharmacy and gender, marital status, and diagnosis of disorder. Male patients were subjected to unnecessary prescriptions and polypharmacy more than female patients. Similarly, De las Cuevas and Sanz reported that men were more often prescribed multiple psychoactive drugs than women, especially those aged 25–45 years. In contrast, several studies have reported higher rates of unnecessary prescriptions and polypharmacy for female patients than males.,,, Salih et al. found no significant gender difference in the prescribing of unnecessary medications and polypharmacy at a tertiary center. The discrepancy in the association between gender and exposure to polypharmacy may be due to differences in socioeconomic, cultural, and educational characteristics between genders, as well as psychiatrists' prescription attitude toward the genders.
We found the prevalence of irrelevant prescription and polypharmacy to be higher for single and divorced patients than for married patients. This could be due to the lower incidence of psychiatric illness among married men and women compared to single, widowed, or divorced. However, Adeponle et al. found no such association in their study of a outpatients psychiatric practice in Nigeria.
We found statistically significant differences in the prevalence of polypharmacy in the different psychiatric diagnoses. Out of six different diagnosis categories, the odds of polypharmacy were higher for patients with psychosis and bipolar disorders than for those who had other psychiatric disorders. Adeponle et al. reported a similarly significant association with regard to psychotropic polypharmacy. De las Cuevas and Sanz also found a psychiatric diagnosis to be the most reliable predictor for polypharmacy as regards psychoactive drugs.
While we found no significant associations between age group, education level, occupation, or body mass index with psychotropic polypharmacy, Adeponle et al. found that respondents' age was an indicator of psychotropic polypharmacy, especially for those aged from 21 to 50 years. De las Cuevas and Sanz and Sim et al. also reported an association between the age of the patient and psychotropic polypharmacy, but no conclusive reason has been cited to explain this., In spite of the study's several strengths, there are a few limitations worth mentioning. The study subjects were outpatients from only two primary care psychiatric clinics, with no in-patients from hospitals and other health-care centers. No causal interpretation of observed findings could be done as this was a cross-sectional observational study.
| Conclusion|| |
Psychotropic polypharmacy in psychiatric outpatient practice is common in Saudi Arabia. Patients with psychosis and bipolar disorders, especially those aged 25–45 years, are exposed to high levels of psychotropic polypharmacy. Since the risk of adverse effects rises with an increase in the number of medications, the concomitant use of many drugs by psychiatric patients should be periodically reviewed.
The authors would like to thank and acknowledge King Abdullah International Medical Research Center for their support of this study, and Ms. Nahrain Quiambao – Sabanal for administrative support and assistance in preparing the manuscript.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]