Polypharmacy as commonly defined is an indicator of limited value in the assessment of drug-related problems

Diakonhjemmet Hospital Pharmacy, Faculty of Medicine, University of Oslo, Oslo, Norway.
British Journal of Clinical Pharmacology (Impact Factor: 3.88). 03/2007; 63(2):187-95. DOI: 10.1111/j.1365-2125.2006.02744.x
Source: PubMed


To investigate whether polypharmacy defined as a definite number of drugs is a suitable indicator for describing the risk of occurrence of drug-related problems (DRPs) in a hospital setting.
Patients admitted to six internal medicine and two rheumatology departments in five hospitals were consecutively included and followed during the hospital stay, with particular attention to medication and DRPs. Comparisons were made between patients admitted with five or more drugs and with less than five drugs. Clinical pharmacists assessed DRPs by reviewing medical records and by participating in multidisciplinary team discussions.
Of a total of 827 patients, 391 (47%) used five or more drugs on admission. Patients admitted with five or more and less than five drugs were prescribed the same number of drugs after admission: 4.1 vs. 3.9 drugs [P = 0.4, 95% confidence interval (CI) - 0.57, 0.23], respectively. The proportion of drugs used on admission which was associated with DRPs was similar in the patient group admitted with five or more drugs and in those admitted with less than five drugs. The number of DRPs per patient increased approximately linearly with the increase in number of drugs used; one unit increase in number of drugs yielded a 8.6% increase in the number of DRPs (95% CI 1.07, 1.10).
The number of DRPs per patient was linearly related to the number of drugs used on admission. To set a strict cut-off to identify polypharmacy and declare that using more than this number of drugs represents a potential risk for occurrence of DRPs, is of limited value when assessing DRPs in a clinical setting.

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Available from: Kirsten K Viktil, Oct 07, 2015
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    • "Causes of readmissions are multi-factorial and many interventions targeted at high-risk patients have been attempted hitherto, albeit with varying degree success (Hansen et al., 2011). Increased age, multiple comorbidities and polypharmacy, widely defined as the use of five or more drugs, have been identified as contributory factors with the highest risk of readmission Kansagara et al. (2011), Viktil et al. (2007). While age and the presence of comorbidities are unmodifiable, polypharmacy may be addressed via a variety of ways such as medication reconciliation and adoption of judicious prescribing strategies Hanlon et al. (1996). "
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    ABSTRACT: Objective: To investigate whether number of doses per day and number of medications are significantly associated with the number of readmissions and to study the association of readmission frequency with other medical and socio-demographic variables. Methods: Retrospective cross-sectional study involving 432 patients who were readmitted within 15. days of previous hospital discharge between January 1, 2013 and March 31, 2013. Relevant medical records were collected from the national electronic databases of every public tertiary hospital in Singapore. Significant variables (. p<. 0.05) were identified using forward selection and modeled using generalized linear mixed models. Results: A total of 649 unplanned readmissions were reviewed. At a multivariable level, number of readmission was significantly associated with the number of medications (. p=. 0.002) and number of doses per day (. p=. 0.003) after adjusting for race, liver disease, schizophrenia and non-compliance. Conclusion: Complex medication regimen (i.e. multiple medications and multiple doses per day) is a statistically significant predictor of number of readmissions. Simplifying therapeutic regimens with alternatives such as longer-acting or fixed-dose combination drugs may facilitate better patient adherence and reduce costly readmissions.
    12/2014; 1:43-47. DOI:10.1016/j.pmedr.2014.10.001
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    • "Where more than one prescription of the same chemical entity was available, these prescriptions were counted only once; different chemical entities within the same drug class were counted separately. There is no consistent definition of polypharmacy, and treating the medication count as a simple binary factor has been shown to be unhelpful [14]. We therefore categorised the cardiovascular medicine count as none, 1 or 2, 3 or 4, 5 or 6, and 7 or more, and the non-cardiovascular medicine count as none, 1 to 3, 4 to 6, 7 to 9, and 10 or more, as a means of capturing the potentially non-linear nature of a medication count. "
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    ABSTRACT: Polypharmacy is often considered suggestive of suboptimal prescribing, and is associated with adverse outcomes. It is particularly common in the context of cardiovascular disease, but it is unclear whether prescribing of multiple cardiovascular medicines, which may be entirely appropriate and consistent with clinical guidance, is associated with adverse outcome. The aim of this study was to assess the relationship between number of prescribed cardiovascular medicines and unplanned non-cardiovascular hospital admissions. A retrospective cohort analysis of 180,815 adult patients was conducted using Scottish primary care data linked to hospital discharge data. Patients were followed up for one year for the outcome of unplanned non-cardiovascular hospital admission. The association between number of prescribed cardiovascular medicines and hospitalisation was modelled using logistic regression, adjusting for key confounding factors including cardiovascular and non-cardiovascular morbidity and non-cardiovascular prescribing. 25.4% patients were prescribed >=1 cardiovascular medicine, and 5.7% were prescribed >=5. At least one unplanned non-cardiovascular admission was experienced by 4.2% of patients. Admissions were more common in patients receiving multiple cardiovascular medicines (6.4% of patients prescribed 5 or 6 cardiovascular medicines) compared with those prescribed none (3.5%). However, after adjusting for key confounders, cardiovascular prescribing was associated with fewer non-cardiovascular admissions (OR 0.66 for 5 or 6 vs. no cardiovascular medicines, 95% CI 0.57-0.75). We found no evidence that increasing numbers of cardiovascular medicines were associated with an increased risk of unplanned non-cardiovascular hospitalisation, following adjustment for confounding. Assumptions that polypharmacy is hazardous and represents poor care should be moderated in the context of cardiovascular disease.
    BMC Family Practice 03/2014; 15(1):58. DOI:10.1186/1471-2296-15-58 · 1.67 Impact Factor
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    • "Majority of hospitalized patients reported to have some kind of DRPs.[456789] According to studies conducted in Norway, 2.6 DRPs occurred per patient in internal medicine ward and the presence of DRPs increased approximately linearly with the number of drugs used, for the range of one to more than 11 drugs.[510] DRPs affect health outcome negatively.[11] "
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    ABSTRACT: Objective: The increasing number of available drugs and drug users, as well as more complex drug regimens led to more side effects and drug interactions and complicates follow-up. The objective of this study was to assess drug-related problems (DRPs) and associated factors in hospitalized patients. Methods: A hospital-based cross-sectional study design was employed. The study was conducted in Jimma University Specialized Hospital, Jimma, located in the south west of Addis Ababa. All patients who were admitted to the medical ward from February 2011 to March 2011 were included in the study. Data on sociodemographic variables, past medical history, drug history, current diagnosis, current medications, vital signs, and relevant laboratory data were collected using semi-structured questionnaire and data collection forms which were filling through patient interview and card review. Data were analyzed using SPSS version 16 for windows. Descriptive statistics, cross-tabs, Chi-square, and logistic regression were utilized. Findings: Out of 257 study participants, 189 (73.5%) had DRPs and a total of 316 DRPs were identified. From the six classes of DRPs studied, 103 (32.6%) cases related to untreated indication or need additional drug therapy, and 49 (15.5%) cases related to high medication dosage. Unnecessary drug therapy in 49 (15.5%) cases, low medication dosage in 44 (13.9%) cases, and ineffective drug therapy in 42 (13.3%) cases were the other classes of problems identified. Noncompliance in 31 (9.8%) cases was the least prevalent DRP. Independent factors which predicted the occurrence of DRPs in the study population were sex, age, polypharmacy, and clinically significant potential drug-drug interactions. The prevalence of DRPs was substantially high (73.5%). Conclusion: Drug-related problems are common among medical ward patients. Indication-related problems, untreated indication and unnecessary drug therapy were the most common types of DRPs among patients of our medical ward.
    Journal of Pharmacy Practice and Research 03/2014; 3(1):1-5. DOI:10.4103/2279-042X.132702
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