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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    • "Inappropriate drug use has been largely studied in the elderly, a population characterized by frailty, polymorbidity and polymedication; fewer studies have addressed the question in internal medicine wards, in which younger patients are admitted. It has been shown that polymorbidity and polymedication were independent risk factors of DRPs, whereas age and gender were not [13] [14]. Elderly and "
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    ABSTRACT: Patients admitted to general internal medicine wards might receive a large number of drugs and be at risk for drug-related problems (DRPs) associated with increased morbidity and mortality. This study aimed to detect suboptimal drug use in internal medicine by a pharmacotherapy evaluation, to suggest treatment optimizations and to assess the acceptance and satisfaction of the prescribers. This was a 6-month prospective study conducted in two internal medicine wards. Physician rounds were attended by a pharmacist and a pharmacologist. An assessment grid was used to detect the DRPs in electronic prescriptions 24h in advance. One of the following interventions was selected, depending on the relevance and complexity of the DRPs: no intervention, verbal advice of treatment optimization, or written consultation. The acceptance rate and satisfaction of prescribers were measured. In total, 145 patients were included, and 383 DRPs were identified (mean: 2.6 DRPs per patient). The most frequent DRPs were drug interactions (21%), untreated indications (18%), overdosages (16%) and drugs used without a valid indication (10%). The drugs or drug classes most frequently involved were tramadol, antidepressants, acenocoumarol, calcium-vitamin D, statins, aspirin, proton pump inhibitors and paracetamol. The following interventions were selected: no intervention (51%), verbal advice of treatment optimization (42%), and written consultation (7%). The acceptance rate of prescribers was 84% and their satisfaction was high. Pharmacotherapy expertise during medical rounds was useful and well accepted by prescribers. Because of the modest allocation of pharmacists and pharmacologists in Swiss hospitals, complementary strategies would be required. Copyright © 2015 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.
    European Journal of Internal Medicine 06/2015; 26(6). DOI:10.1016/j.ejim.2015.05.012 · 2.89 Impact Factor
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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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