The role of medication noncompliance and adverse drug reactions in hospitalizations of the elderly

We interviewed 315 consecutive elderly patients admitted to an acute care hospital to determine the percentage of elderly hospital admissions due to noncompliance with medication regimens or adverse drug reactions, their causes, consequences, and predictors. Eighty-nine of the elderly admissions (28.2%) were drug related, 36 due to noncompliance (11.4%), and 53 due to adverse drug reactions (16.8%). One hundred three patients had a history of noncompliance (32.7%). Factors statistically associated with a higher risk of hospitalization due to noncompliance were poor recall of medication regimen, seeing numerous physicians, female, medium income category, use of numerous medications, and having the opinion that medications are expensive. Factors associated with an increased risk of an admission due to an adverse drug reaction were use of numerous different medications, higher medication costs, receiving Medicaid, and not receiving any home services. In conclusion, many elderly admissions are drug related; noncompliance accounting for a substantial fraction of these. Elders at high risk of being noncompliant are identifiable using a variety of criteria. Economic factors were important in predicting admissions due to noncompliance as well as adverse drug reactions.     

Inappropriate medication prescribing for elderly ambulatory care patients

BACKGROUND: Inappropriate medication use in elderly patients has been linked to a large share of adverse drug reactions and to excess health care utilization. METHODS: Trends in the prevalence of potentially inappropriate drug prescribing at ambulatory care visits by elderly persons from 1995 to 2000 were examined with data from office-based physicians in the National Ambulatory Medical Care Survey and from hospital outpatient departments in the National Hospital Ambulatory Medical Care Survey. Explicit criteria were used to identify potentially inappropriate prescribing. Multivariate regression was used to identify related factors. RESULTS: In 1995 and 2000, at least 1 drug considered inappropriate by the Beers expert panel was prescribed at 7.8% of ambulatory care visits by elderly patients. At least 1 drug classified as never or rarely appropriate by the Zhan expert panel was prescribed at 3.7% and 3.8% of these visits in 1995 and 2000, respectively. Pain relievers and central nervous system drugs were a large share of the problem. The odds of potentially inappropriate prescribing were higher for visits with multiple drugs and double for female visits. The latter was due to more prescribing of potentially inappropriate pain relievers and central nervous system drugs. CONCLUSIONS: Potentially inappropriate prescribing at ambulatory care visits by elderly patients, particularly women, remains a substantial problem. Interventions could target more appropriate drug selection by physicians when prescribing pain relievers, antianxiety agents, sedatives, and antidepressants to elderly patients. Such behavior could eliminate a large portion of inappropriate prescribing for elderly patients and reduce its higher risk for women.     

Adverse drug reactions related to hospital admission in Slovak elderly patients

The aims of the present study were: to evaluate the prevalence of adverse drug reactions (ADRs) leading to hospitalization in elderly patients; to analyze the drugs which have been identified as having causal relationship with ADRs and to identify risk factors which predispose the patient to such ADRs. The study has been performed in 600 patients aged> or =65 years, hospitalized in a general hospital between 1 December 2003 and 31 March 2005. The ADRs recorded in patient's documentation as one of the reasons for hospital admission were evaluated. ADRs leading to hospital admission were recorded in 47 (7.8%) patients. ADRs in 43 patients represented A-type ADRs which are preventable. The most frequent ADRs were cardiovascular disorders. According to the results of multivariate analysis ischemic heart disease (odds ratio (OR)=4.50; 95% confidence interval (CI)=1.36-14.88), depression (OR, 2.49; 95% CI, 1.08-5.77) and heart failure (OR, 2.08; 95% CI, 1.13-3.81) were the most important patient-related characteristics predicting ADRs leading to hospitalization. The majority of ADRs in elderly patients could be avoided. Regular re-evaluation of the medication as well as taking into account the specific features of elderly patients represent the most important tools for ADR prevention.     

An assessment of inappropriate hospital bed utilization by elderly patients in southern Italy

BACKGROUND AND AIMS: The aims of this study were to quantify the rate of inappropriate hospital admissions and days of stay among elderly patients, and to identify the main causes of such inappropriateness. METHODS: A random sample of 560 medical records of patients aged 65 and over, admitted to medical and surgical wards of a non-teaching hospital in Catanzaro (Italy) were reviewed (occupation rate: 81.9%, average length of stay: 5.6 days; hospitalization rate in the area: 130.8 per 1,000 inhabitants). RESULTS: Of the 529 patient days reviewed, 9.8% of hospital admissions were judged to be inappropriate, and the level of inappropriate hospital days of stay was 39.5%. The inappropriateness of admission was significantly higher for younger patients and for those whose admission was programmed. Demographic and hospital variables were significant predictors of the risk of inappropriateness per day of care: women, those not living alone, patients admitted with a more severe burden of overall comorbidity, patients inappropriately admitted, and those sampled close to discharge were more likely to be classified as inappropriate. Inappropriate admission was due to premature admission, an overcautious physician's attitude in the management of a patient, and admission for a diagnostic or therapeutic procedure that should have been performed on an out-patient basis. The reasons for inappropriate hospital stay were: physician's lack of decision regarding discharge of a patient and delays in scheduling a diagnostic or therapeutic procedure. CONCLUSION: Interventions are needed in order to increase the quality and efficiency of hospital care, by rectifying the attitudes and behaviors of Italian physicians.     

Readmissions and adverse drug reactions in internal medicine: the economic impact

BACKGROUND: Recent studies show that nearly half of the hospitalized patients are readmitted within 6 months from discharge. No data exist about the relationship between adverse drug reactions (ADRs) and readmittance to a department of internal medicine. OBJECTIVES: The primary aims of the study were to determine if ADRs could be used as predictors for recurrent hospitalizations in internal medicine and to evaluate the economic impact of ADRs on hospitalization costs. DESIGN AND SETTING: A cohort-based, prospective, 18-month pharmacoepidemiological survey was conducted in the Department I of Internal Medicine at the University Hospital of Erlangen. All patients were intensively monitored for ADRs by a pharmacoepidemiological team. ADRs were evaluated for their offending drugs, probability, severity, preventability and classified by WHO-ART. During a 6-month period ADR-positive patients were matched to non-ADR patients applying diagnosis-related group categorization in order to measure the impact of ADRs on the duration and frequency of hospitalization. RESULTS: Of 1000 admissions 424 patients had single admissions and 206 patients had recurrent readmissions (min 1, max 9). The prevalence of readmissions was 37% (n = 370). In 145 (23%) of 630 patients, 305 ADRs were observed. The ADR incidence was similar in first admissions and readmissions. ADRs were not found to predict further readmissions and lack of ADRs did not preclude readmissions. ADRs caused hospitalizations in 6.2% of first admissions and in 4.2% of readmissions. According to the Schumock algorithm 135 (44.3%) ADRs were found to be preventable. The occurrence and numbers of ADRs per admission were found to prolong hospitalization period significantly (r = 0.48 and 0.51, P < 0.001, n = 135). Of 9107 treatment days 20% were caused by in-house (1130 days) and community-acquired ADRs (669 days). In admissions and readmissions 11% (>973 days) of all treatment days were judged to be preventable. CONCLUSIONS: Intensified drug monitoring supported by information technology in internal medicine is essential for early detecting and prevention of ADRs and saving hospital resources.     

Prescribing behavior for the elderly in the United Arab Emirates: psychotropic medication use remains low despite rising overall appropriate and inappropriate medication use

Inappropriate prescribing, especially for psychotropic agents, is a common and significant cause of morbidity in older people. This cross sectional survey was conducted in the United Arab Emirates (UAE), a country with a rapidly developing economy. Prescribing behavior for people aged 65+ years acutely admitted via a university teaching hospital was examined for 1994 and 1999. All 474 patients (which resulted in 627 acute admissions; 194 in 1994 and 433 in 1999) were included. The patients had a mean age of 74.1 +/- 7.6, mean annual admission rate of 1.3 +/- 0.8 and a female:male ratio of 0.46 in 1994 rising to 0.73 in 1999 (P=0.04). Pre-admission use of five or more medications as recorded in the admission notes increased from 12% in 1994 to 23% in 1999 (P=0.001), while on discharge rose from 26 to 45% (P<0.001). There was a rise in low dose aspirin use, an indicator of appropriate prescribing, both pre-hospital (13-21%, P=0.03) and on discharge (19-29%, P=0.007). There was also a significant rise in pre-hospital inappropriate prescribing from 5 to 13% of patients demonstrating at least 1 of 144 inappropriate medications or combinations looked for (P=0.002) and at discharge from 9 to 19% (P=0.001). The rate of psychotropic medication usage (pre-hospital 0.1 per person: at discharge 0.25) was low compared to western countries and showed no significant change over time. These findings show rises in both appropriate and inappropriate prescribing with the exception of psychotropic medications during a 5-year period, which corresponded to rapid development in the health care system.     

Potentially Inappropriate Medications and Functional Decline in Elderly Hospitalized Patients

OBJECTIVES: To verify whether the use of potentially inappropriate medications (PIMs) is associated with loss of independence in elderly in-patients by promoting adverse drug reactions (ADRs).
DESIGN: Prospective observational study.
PARTICIPANTS: Five hundred six patients aged 65 and older admitted to 11 acute care medical wards.
MEASUREMENTS: In-hospital loss of one or more activities of daily living (ADLs) and three or more ADLs. PIMs were identified according to diagnosis-independent Beers criteria and ascertained by study physicians based on daily review of medical and nurse records. The relationship between risk factors and outcomes was assessed using logistic regression.
RESULTS: Overall, 104 patients (20.6%) were taking at least one PIM at the time of admission (baseline users), and 49 (9.7%) were newly prescribed at least one PIM during their hospital stay. The loss of one or more ADLs occurred in 9.6% of baseline users, 16.3% of new users, and 8.5% of nonusers ( P =.21) and that of three or more ADLs in 7.7% of baseline users, 12.2% of new users, and 4.8% of nonusers ( P =.10). The lack of association was confirmed after correction for potential confounders, including ADRs. The occurrence of ADRs was strongly associated with both outcomes (odds ratio (OR)=7.80, 95% confidence interval (CI)=3.53–17.3 for the loss of ≥1 ADLs; OR=3.98, 95% CI=1.50–10.5 for the loss of ≥3 ADLs), but PIMs caused only six of 106 ADRs.
CONCLUSIONS: ADRs to any drugs more than the use of PIMs might be associated with functional decline in elderly hospitalized patients, but because the power of this study was too limited to definitively exclude a direct relationship between PIMs and functional decline, this merits further investigation.     

Hospitalization due to adverse drug reactions and drug interactions before and after HAART.

OBJECTIVE: To characterize and compare the rates of adverse drug reactions (ADRs) and interactions on admission in two, one-year periods: pre-highly active antiretroviral therapy (HAART) (phase 1) and post-HAART (phase 2). DESIGN: Retrospective chart review. SETTING: University-affiliated tertiary care centre. POPULATION STUDIED: HIV-positive patients admitted to hospital. MAIN RESULTS: In phase 1, 436 of 517 admissions, and, in phase 2, 323 of 350 admissions were analyzed. Over 92% of patients were male, with a mean age of 38 years. Significant differences (P<0.05) in the mean length of stay (12.08 versus 10.02 days), the CD4 counts (99.25 versus 129.45) and the number of concurrent diseases (4.20 versus 3.63) were found between phase 1 and 2, respectively. The mean number of medications taken (5.52 versus 5.94) and the rates of hospitalization with ADRs (20.4% versus 21.4%) or interactions (2.5% versus 2.16%) were similar between the two phases. Antiretrovirals were more common in ADR admissions post-HAART (21.3% versus 36.2%), while antiparasitics, psychotherapeutics and antineoplastics were more common pre-HAART. Other classes of drugs involved in both phases were sulphonamides, narcotics, ganciclovir, foscarnet, antimycobacterials and antifungals. ADR causality was possible or probable in more than 80% of cases. Over 60% of ADRs were grades 3 to 4, and about 85% were either the main or contributing reason for admission. About 65% of patients had at least partial recovery at the time of discharge. In phases 1 and 2, 8.9% and 2.9% of admissions,respectively, with ADRs were fatal. CONCLUSIONS: Although hospitalizations with ADRs and interactions were similar in both phases, HAART therapy has had a significant impact on the incidence and nature of ADRs at St Michael's Hospital, Wellesley Central Site, Toronto, Ontario.     

Polypharmacy and prescribing quality in older people

OBJECTIVES: To evaluate the relationship between inappropriate prescribing, medication underuse, and the total number of medications used by patients. DESIGN: Cross-sectional study. SETTING: Veterans Affairs Medical Center. PARTICIPANTS: One hundred ninety-six outpatients aged 65 and older who were taking five or more medications. MEASUREMENTS: Inappropriate prescribing was assessed using a combination of the Beers drugs-to-avoid criteria (2003 update) and subscales of the Medication Appropriateness Index that assess whether a drug is ineffective, not indicated, or unnecessary duplication of therapy. Underuse was assessed using the Assessment of Underutilization of Medications instrument. All vitamins and minerals, topical and herbal medications, and medications taken as needed were excluded from the analyses. RESULTS: Mean age was 74.6, and patients used a mean+/-standard deviation of 8.1+/-2.5 medications (range 5-17). Use of one or more inappropriate medications was documented in 128 patients (65%), including 73 (37%) taking a medication in violation of the Beers drugs-to-avoid criteria and 112 (57%) taking a medication that was ineffective, not indicated, or duplicative. Medication underuse was observed in 125 patients (64%). Together, inappropriate use and underuse were simultaneously present in 82 patients (42%), whereas 25 (13%) had neither inappropriate use nor underuse. When assessed by the total number of medications taken, the frequency of inappropriate medication use rose sharply from a mean of 0.4 inappropriate medications in patients taking five to six drugs, to 1.1 inappropriate medications in patients taking seven to nine drugs, to 1.9 inappropriate medications in patients taking 10 or more drugs (P<.001). In contrast, the frequency of underuse averaged 1.0 underused medications per patient and did not vary with the total number of medications taken (P=.26). Overall, patients using fewer than eight medications were more likely to be missing a potentially beneficial drug than to be taking a medication considered inappropriate. CONCLUSION: Inappropriate medication use and underuse were common in older people taking five or more medications, with both simultaneously present in more than 40% of patients. Inappropriate medication use is most frequent in patients taking many medications, but underuse is also common and merits attention regardless of the total number of medications taken.     

Improvement of inappropriate prescribing and adverse drug withdrawal events after admission to long-term care facilities

Background: The objectives of this study were to determine whether medications, particularly inappropriate prescribing, would be reduced after admission to long‐term care facilities, and whether adverse drug withdrawal events (ADWEs) would occur in relation to discontinuation of medications. Methods: The study consists of a retrospective survey using medical chart review in five health service facilities for the elderly in Japan. All the patients who were admitted to the facilities between January 2001 and December 2002 (N = 627) were participants in the study. Medications taken on admission, at 1 month and 3 months after admission, and events (significant worsening of the disease status, accidents, new symptoms and signs, and other acute events) during a 3‐month period were recorded. Inappropriate prescribing was determined using Beers’ criteria with some modification. ADWEs were determined using the Naranjo causality algorithm. Results: On admission, the patients were taking 3.5 ± 2.5 (mean ± SD) drugs. One month later, the number of prescribed drugs was decreased by 17% (P < 0.01 vs on admission), but did not show an additional reduction 3 months later. Inappropriate prescribing was found in 10% of the patients taking drugs on admission, but the number of inappropriately prescribed medications was reduced by 33% after 1 month. Of 105 events recorded, only five (2% of the patients with drug reduction) were considered ADWEs; three cases of confusion, a case of depression, and a case of hyperglycemia, following discontinuation of psychotropic drugs, antidepressants and a sulfonylurea, respectively. Conclusion: Adverse drug withdrawal events were not frequent despite the significant reduction of medications after admission to long‐term care facilities. This might be because the rate of reduction was relatively high for inappropriately prescribed medications.     

Unnecessary drug use in frail older people at hospital discharge

OBJECTIVES: To determine the prevalence and predictors of unnecessary drug use at hospital discharge in frail elderly patients. DESIGN: Cross-sectional. SETTING: Eleven Veterans Affairs Medical Centers. PARTICIPANTS: Three hundred eighty-four frail older patients from the Geriatric Evaluation and Management Drug Study. MEASUREMENTS: Assessment of unnecessary drug use was determined by the consensus of a clinical pharmacist and physician pair applying the Medication Appropriateness Index to each regularly scheduled medication at hospital discharge. Those drugs that received an inappropriate rating for indication, efficacy, or therapeutic duplication were defined as unnecessary. RESULTS: Forty-four percent of patients had at least one unnecessary drug, with the most common reason being lack of indication. The most commonly prescribed unnecessary drug classes were gastrointestinal, central nervous system, and therapeutic nutrients/minerals. Factors associated (P<.05) with unnecessary drug use included hypertension (adjusted odds ratio (AOR)=0.61, 95% confidence interval (CI)=0.38-0.96), multiple prescribers (AOR=3.35, 95% CI=1.16-9.68), and nine or more medications (AOR=2.24, 95% CI=1.25-3.99). CONCLUSION: A high prevalence of unnecessary drug use at discharge was found in frail hospitalized elderly patients. Additional studies are needed to identify predictors and prevalence of unnecessary drug use in nonveteran populations so that interventions can be designed to reduce the problem.