Support Care Cancer DOI 10.1007/s00520-014-2171-x
ORIGINAL ARTICLE
Prevalence and factors associated with polypharmacy in older people with cancer Justin P. Turner & Sepehr Shakib & Nimit Singhal & Jonathon Hogan-Doran & Robert Prowse & Sally Johns & J. Simon Bell
Received: 9 January 2014 / Accepted: 10 February 2014 # Springer-Verlag Berlin Heidelberg 2014
Abstract Purpose Polypharmacy has been associated with drug–drug interactions, adverse drug events, hospitalisation and increased mortality. The purpose of this study was to investigate the prevalence and factors associated with polypharmacy in older people with cancer. Patients and methods Patients aged ≥70 years (n=385) presenting to the medical oncology outpatient clinic at Royal Adelaide Hospital between January 2009 and July 2010 completed a structured data collection instrument. The instrument included domains related to medications, diagnoses, instrumental activities of daily living (IADLs), Karnofsky Performance Scale (KPS), physical function (SF-36), pain (ten-point visual analogue scale, VAS), weight loss (patient self-reported over previous 6 months), exhaustion (CES-D) and distress (ten-point VAS). Frailty was computed using Fried’s frailty phenotype. Logistic regression was used to compute unadjusted and adjusted odds ratios (ORs) and 95% confidence intervals
(CIs) for the association between polypharmacy (defined as five or more self-reported daily medications) and clinical parameters. Results Polypharmacy was present in 57 % (n=221) of patients. When adjusting for age, gender and Charlson Comorbidity Index (CCI), polypharmacy was associated with being pre-frail (OR=2.35, 95%CI=1.43–3.86) and frail (OR=4.48, 95%CI=1.90–10.54) compared to being robust. When adjusting for age, gender, exhaustion, KPS, IADLs, pain and distress, polypharmacy was associated with higher CCI scores (OR=1.58, 95%CI=1.29–1.94) and poorer physical function (OR=1.13, 95%CI=1.06–1.20). Conclusions Polypharmacy is highly prevalent in older people with cancer and associated with impaired physical function and being pre-frail and frail compared to being robust. Research is needed to identify strategies to minimize patients’ medication regimens.
J. P. Turner : J. S. Bell School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia, Australia
Keywords Aged . Aged 80 and over . Frail elderly . Geriatric oncology . Medical oncology . Polypharmacy
J. P. Turner (*) : J. S. Bell Centre for Medicine Use and Safety, Faculty of Pharmacy and Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, 3052 Melbourne, Victoria, Australia e-mail: [email protected] S. Shakib : S. Johns Department of Clinical Pharmacology, Royal Adelaide Hospital, Adelaide, South Australia, Australia N. Singhal : J. Hogan-Doran University of Adelaide and Department of Medical Oncology, Royal Adelaide Hospital, Adelaide, South Australia, Australia R. Prowse Department of Geriatric and Rehabilitation Medicine, Royal Adelaide Hospital, Adelaide, South Australia, Australia
Introduction Cancer is predominantly a disease of older people. Over 50 % of cancer diagnoses and 70 % of cancer mortality occur in patients aged ≥65 years [1]. With increasing life expectancy, the number of older people with cancer will continue to increase [2, 3]. Older people have a higher prevalence of multimorbidity and polypharmacy [2]. Agerelated changes in pharmacokinetics and pharmacodynamics mean older people are susceptible to adverse drug events (ADEs) [4, 5]. Use of medications for which there is no clinical indication may reduce survival and patients’ ability to tolerate cancer treatment [6].
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Polypharmacy is often defined as use of five or more medications [7]. Using this definition, the reported prevalence of polypharmacy in community-dwelling older people ranges from 44 to 57 % [8, 9]. In a recent study, 80 % of people with newly diagnosed cancer took five or more regular non-cancer medications [10]. Another study reported that 32 % of people admitted to an acute care geriatric oncology unit took nine or more regular non-cancer medications [11]. Polypharmacy in older people has been associated with drug–drug interactions [12, 13], ADEs [4, 8], hospitalisations [4, 14], potentially inappropriate medication use [11, 15, 16] and increased mortality [17]. A population-based cohort study of people newly diagnosed with cancer identified that polypharmacy increased in the 6 months prior to diagnosis, which may reflect use of medications to treat early signs and symptoms of cancer [18]. However, to date, few studies have investigated the factors associated with polypharmacy in older people with cancer. Among older people newly diagnosed with cancer using daily medications, 62 % experienced a potential medication-related problem [19]. There was a strong association between polypharmacy and moderate/severe medicationrelated problems (OR=16.0, 95%CI=5.1–50.3). Patients with cancer are potentially at increased risk of harm due to polypharmacy. Firstly, there is an increased potential for drug–drug interactions arising from the use of chemotherapy or supportive treatments [20, 21]. An audit of records of 100 patients in an oncology ward revealed that 63 % had at least one potential drug–drug interaction, of which 18 % were considered severe [22]. Secondly, older people with cancer often take complementary and alternative medicines (CAMs). The use of CAMs may be not be disclosed to clinicians, yet CAMs may interact with cancer treatment [23]. Finally, older people with cancer have a higher prevalence of geriatric syndromes and, thus, may be more susceptible to ADEs [1]. To our knowledge, no previous study has investigated possible associations between polypharmacy and geriatric syndromes such as frailty, reduced physical function, instrumental activities of daily living (IADLs), exhaustion, pain and distress. The objective of this study was to investigate the prevalence and factors associated with polypharmacy in people presenting to an outpatient medical oncology clinic.
Methods Study participants and setting The study was conducted at the Royal Adelaide Hospital (RAH). This is a 650-bed tertiary referral hospital located in metropolitan Adelaide, South Australia. All patients aged ≥70 years who presented to the medical oncology outpatient
clinic at RAH between January 2009 and July 2010 were eligible for inclusion in the study [24]. Patients were either referred to the medical oncology outpatient clinic by their general medical practitioner or from another department within the RAH. Data collection Patients were mailed a structured data collection instrument based on the principles of comprehensive geriatric assessment prior to their initial appointment at the medical oncology outpatient clinic. This was completed by the patient with or without assistance from their carer/family member. Any sections of the structured data collection instrument which were incomplete were completed in conjunction with a nurse at the initial appointment. Each patient was discussed at an initial geriatric oncology multidisciplinary team meeting consisting of a geriatrician, medical oncologist, geriatric oncology nurse, social worker, dietician, pharmacist, occupational therapist and palliative care nurse and the treatment intent (palliative, nonpalliative or unknown) was documented in the treatment notes. The data collection instrument included sections about each patient’s age, gender, diagnoses, medications, pain (assessed using a ten-point visual analogue scale, VAS), distress (assessed using a ten-point VAS) [25], IADLs [26], Karnofsky Performance Scale (KPS) [27], SF-36 physical function domains [28], self-reported weight loss during the previous 6 months and exhaustion (using two questions from the CES-D scale [29], as adapted in [30]). Medication use Each patient self-reported their medication on the structured data collection instrument. Data about prescription, nonprescription and CAMs were collected separately to ensure a full medication history was obtained. Medication use was assessed as the point prevalence at each patient’s initial appointment. A nurse with access to each patient’s medical records confirmed the self-reported medication list at the initial appointment. If the nurse identified that the patient took an additional medication not self-reported using the structured data collection instrument, it was added to the list. The validity of the patient self-reported medication list was estimated by comparing a sample of 30 medication lists to those obtained from an interview conducted by a clinical pharmacist. There was a 79 % concordance for prescription medications [31]. This level of concordance is comparable to medication histories routinely used in hospital wards [32]. Measures and definitions All medications were coded as International Non-proprietary Names and Anatomical Therapeutic Chemical (ATC) codes
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recommended by the World Health Organization [33]. Polypharmacy was defined as use of five or more medications on a regular basis, including non-prescription medications and CAMs. Frailty was assessed using an adapted version of Fried’s frailty phenotype [3, 24, 30]. We assessed the same five criteria that comprise Fried’s frailty phenotype using variables included in the data collection instrument based on the principles of comprehensive geriatric assessment. These five criteria were weight loss of >5 % during the preceding 6 months, an exhaustion score ≥3, dependence in at least one IADL, dependence in at least one SF-36 physical function domain and KPS
ORIGINAL ARTICLE
Prevalence and factors associated with polypharmacy in older people with cancer Justin P. Turner & Sepehr Shakib & Nimit Singhal & Jonathon Hogan-Doran & Robert Prowse & Sally Johns & J. Simon Bell
Received: 9 January 2014 / Accepted: 10 February 2014 # Springer-Verlag Berlin Heidelberg 2014
Abstract Purpose Polypharmacy has been associated with drug–drug interactions, adverse drug events, hospitalisation and increased mortality. The purpose of this study was to investigate the prevalence and factors associated with polypharmacy in older people with cancer. Patients and methods Patients aged ≥70 years (n=385) presenting to the medical oncology outpatient clinic at Royal Adelaide Hospital between January 2009 and July 2010 completed a structured data collection instrument. The instrument included domains related to medications, diagnoses, instrumental activities of daily living (IADLs), Karnofsky Performance Scale (KPS), physical function (SF-36), pain (ten-point visual analogue scale, VAS), weight loss (patient self-reported over previous 6 months), exhaustion (CES-D) and distress (ten-point VAS). Frailty was computed using Fried’s frailty phenotype. Logistic regression was used to compute unadjusted and adjusted odds ratios (ORs) and 95% confidence intervals
(CIs) for the association between polypharmacy (defined as five or more self-reported daily medications) and clinical parameters. Results Polypharmacy was present in 57 % (n=221) of patients. When adjusting for age, gender and Charlson Comorbidity Index (CCI), polypharmacy was associated with being pre-frail (OR=2.35, 95%CI=1.43–3.86) and frail (OR=4.48, 95%CI=1.90–10.54) compared to being robust. When adjusting for age, gender, exhaustion, KPS, IADLs, pain and distress, polypharmacy was associated with higher CCI scores (OR=1.58, 95%CI=1.29–1.94) and poorer physical function (OR=1.13, 95%CI=1.06–1.20). Conclusions Polypharmacy is highly prevalent in older people with cancer and associated with impaired physical function and being pre-frail and frail compared to being robust. Research is needed to identify strategies to minimize patients’ medication regimens.
J. P. Turner : J. S. Bell School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia, Australia
Keywords Aged . Aged 80 and over . Frail elderly . Geriatric oncology . Medical oncology . Polypharmacy
J. P. Turner (*) : J. S. Bell Centre for Medicine Use and Safety, Faculty of Pharmacy and Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, 3052 Melbourne, Victoria, Australia e-mail: [email protected] S. Shakib : S. Johns Department of Clinical Pharmacology, Royal Adelaide Hospital, Adelaide, South Australia, Australia N. Singhal : J. Hogan-Doran University of Adelaide and Department of Medical Oncology, Royal Adelaide Hospital, Adelaide, South Australia, Australia R. Prowse Department of Geriatric and Rehabilitation Medicine, Royal Adelaide Hospital, Adelaide, South Australia, Australia
Introduction Cancer is predominantly a disease of older people. Over 50 % of cancer diagnoses and 70 % of cancer mortality occur in patients aged ≥65 years [1]. With increasing life expectancy, the number of older people with cancer will continue to increase [2, 3]. Older people have a higher prevalence of multimorbidity and polypharmacy [2]. Agerelated changes in pharmacokinetics and pharmacodynamics mean older people are susceptible to adverse drug events (ADEs) [4, 5]. Use of medications for which there is no clinical indication may reduce survival and patients’ ability to tolerate cancer treatment [6].
Support Care Cancer
Polypharmacy is often defined as use of five or more medications [7]. Using this definition, the reported prevalence of polypharmacy in community-dwelling older people ranges from 44 to 57 % [8, 9]. In a recent study, 80 % of people with newly diagnosed cancer took five or more regular non-cancer medications [10]. Another study reported that 32 % of people admitted to an acute care geriatric oncology unit took nine or more regular non-cancer medications [11]. Polypharmacy in older people has been associated with drug–drug interactions [12, 13], ADEs [4, 8], hospitalisations [4, 14], potentially inappropriate medication use [11, 15, 16] and increased mortality [17]. A population-based cohort study of people newly diagnosed with cancer identified that polypharmacy increased in the 6 months prior to diagnosis, which may reflect use of medications to treat early signs and symptoms of cancer [18]. However, to date, few studies have investigated the factors associated with polypharmacy in older people with cancer. Among older people newly diagnosed with cancer using daily medications, 62 % experienced a potential medication-related problem [19]. There was a strong association between polypharmacy and moderate/severe medicationrelated problems (OR=16.0, 95%CI=5.1–50.3). Patients with cancer are potentially at increased risk of harm due to polypharmacy. Firstly, there is an increased potential for drug–drug interactions arising from the use of chemotherapy or supportive treatments [20, 21]. An audit of records of 100 patients in an oncology ward revealed that 63 % had at least one potential drug–drug interaction, of which 18 % were considered severe [22]. Secondly, older people with cancer often take complementary and alternative medicines (CAMs). The use of CAMs may be not be disclosed to clinicians, yet CAMs may interact with cancer treatment [23]. Finally, older people with cancer have a higher prevalence of geriatric syndromes and, thus, may be more susceptible to ADEs [1]. To our knowledge, no previous study has investigated possible associations between polypharmacy and geriatric syndromes such as frailty, reduced physical function, instrumental activities of daily living (IADLs), exhaustion, pain and distress. The objective of this study was to investigate the prevalence and factors associated with polypharmacy in people presenting to an outpatient medical oncology clinic.
Methods Study participants and setting The study was conducted at the Royal Adelaide Hospital (RAH). This is a 650-bed tertiary referral hospital located in metropolitan Adelaide, South Australia. All patients aged ≥70 years who presented to the medical oncology outpatient
clinic at RAH between January 2009 and July 2010 were eligible for inclusion in the study [24]. Patients were either referred to the medical oncology outpatient clinic by their general medical practitioner or from another department within the RAH. Data collection Patients were mailed a structured data collection instrument based on the principles of comprehensive geriatric assessment prior to their initial appointment at the medical oncology outpatient clinic. This was completed by the patient with or without assistance from their carer/family member. Any sections of the structured data collection instrument which were incomplete were completed in conjunction with a nurse at the initial appointment. Each patient was discussed at an initial geriatric oncology multidisciplinary team meeting consisting of a geriatrician, medical oncologist, geriatric oncology nurse, social worker, dietician, pharmacist, occupational therapist and palliative care nurse and the treatment intent (palliative, nonpalliative or unknown) was documented in the treatment notes. The data collection instrument included sections about each patient’s age, gender, diagnoses, medications, pain (assessed using a ten-point visual analogue scale, VAS), distress (assessed using a ten-point VAS) [25], IADLs [26], Karnofsky Performance Scale (KPS) [27], SF-36 physical function domains [28], self-reported weight loss during the previous 6 months and exhaustion (using two questions from the CES-D scale [29], as adapted in [30]). Medication use Each patient self-reported their medication on the structured data collection instrument. Data about prescription, nonprescription and CAMs were collected separately to ensure a full medication history was obtained. Medication use was assessed as the point prevalence at each patient’s initial appointment. A nurse with access to each patient’s medical records confirmed the self-reported medication list at the initial appointment. If the nurse identified that the patient took an additional medication not self-reported using the structured data collection instrument, it was added to the list. The validity of the patient self-reported medication list was estimated by comparing a sample of 30 medication lists to those obtained from an interview conducted by a clinical pharmacist. There was a 79 % concordance for prescription medications [31]. This level of concordance is comparable to medication histories routinely used in hospital wards [32]. Measures and definitions All medications were coded as International Non-proprietary Names and Anatomical Therapeutic Chemical (ATC) codes
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recommended by the World Health Organization [33]. Polypharmacy was defined as use of five or more medications on a regular basis, including non-prescription medications and CAMs. Frailty was assessed using an adapted version of Fried’s frailty phenotype [3, 24, 30]. We assessed the same five criteria that comprise Fried’s frailty phenotype using variables included in the data collection instrument based on the principles of comprehensive geriatric assessment. These five criteria were weight loss of >5 % during the preceding 6 months, an exhaustion score ≥3, dependence in at least one IADL, dependence in at least one SF-36 physical function domain and KPS
