BACKGROUND:The prescribing cascade model involves the misinterpretation of an adverse reaction to 1 drug and the subsequent, potentially inappropriate prescription of a second drug. We present a new example of the prescribing cascade involving cholinesterase inhibitors and anticholinergic drugs used to manage urinary incontinence.METHODS:A population-based retrospective cohort study was carried out in Ontario, Canada. Participants included 44,884 older adults with dementia (20,491 were dispensed a cholinesterase inhibitor and 24,393 were not), enrolled between June 1, 1999, and March 31, 2002. Subjects were observed until they received an anticholinergic drug, stopped the cholinesterase inhibitor treatment, died, or the study period ended (March 31, 2003). The main outcome measure was receipt of an anticholinergic drug to manage urinary incontinence.RESULTS:After adjusting for potential confounding factors, we observed that older adults with dementia who were dispensed cholinesterase inhibitors had an increased risk of subsequently receiving an anticholinergic drug (4.5% vs 3.1%; P<.001; adjusted hazard ratio, 1.55; 95% confidence interval, 1.39-1.72), relative to those not receiving cholinesterase inhibitors. This finding was consistent in a series of subgroup analyses.CONCLUSIONS:Use of cholinesterase inhibitors is associated with an increased risk of receiving an anticholinergic drug to manage urinary incontinence. The use of an anticholinergic drug in this setting may represent a clinically important prescribing cascade. Clinicians should consider the possible contributing role of cholinesterase inhibitors in new-onset or worsening urinary incontinence and the potential risk of coprescribing cholinesterase inhibitors and anticholinergic drugs to patients with dementia.

Objective: To determine the relation between rehabilitation therapy (RT) intensity and time to discharge home for stroke patients in skilled nursing facilities (SNFs).Design: Retrospective cohort study. We used regression analyses, stratified by expected outcome, and propensity score adjustment.Setting: All SNFs in Ohio, Michigan, and Ontario, Canada.Participants: A cohort of residents, aged 65 and over, admitted from hospitals to SNFs with a diagnosis of stroke (N = 23,824).Interventions: Not applicable.Main Outcome Measure: Time to discharge home from an SNF.Results: RT was given to more than 95% of residents for whom discharge was expected within 90 days and to more than 60% of residents for whom discharge was uncertain or not expected. RT increased the likelihood of discharge to the community for all groups except those expected to be discharged within 30 days. The dose-response relation was strongest for residents with either an uncertain discharge prognosis or no discharge expected.Conclusions: Postacute residents with an uncertain prognosis are an important target population for intensive RT. (C) 2005 by American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation.

BACKGROUND:Atypical antipsychotic agents are thought to be less likely than older typical agents to produce parkinsonism. This has not been well documented. We compared the risk of development of incident parkinsonism among older adults dispensed atypical relative to typical antipsychotics.METHODS:Retrospective cohort study of all adults 66 years and older in Ontario. We used Cox proportional hazards models to study the association between the type, potency, and dose of antipsychotic dispensed and the development of parkinsonism during 1 year of follow-up.RESULTS:All 25,769 older adults prescribed antipsychotics were observed for 11,573 person-years, and 449 events of parkinsonism were identified. Relative to individuals dispensed an atypical antipsychotic, those dispensed a typical agent were 30% more likely (adjusted hazard ratio [HR], 1.30; 95% confidence interval [CI], 1.04-1.58) and those exposed to neither agent were 60% less likely (HR, 0.40; 95% CI, 0.29-0.43) to experience development of parkinsonism. Furthermore, those dispensed lower-potency typical agents were no different (HR, 0.75; 95% CI, 0.48-1.15), and those dispensed higher-potency typical antipsychotics were at close to a 50% greater risk (HR, 1.44; 95% CI, 1.13-1.84) of development of parkinsonism relative to atypical antipsychotics. Relative to those dispensed a high-dose atypical antipsychotic, those dispensed a typical antipsychotic were at similar risk for parkinsonism (Wald chi(2) = 0.14, P = .7).CONCLUSIONS:The risk of development of parkinsonism associated with the use of high-dose atypical antipsychotics was similar to that associated with the use of typical antipsychotics. Caution should be used when prescribing atypical antipsychotic therapy at high doses.

OBJECTIVES: To compare patterns of potentially inappropriate drug therapy prescribing in community-dwelling older adults and nursing home residents in Ontario, Canada.DESIGN: A retrospective cohort study using administrative databases.SETTING: Ontario community and nursing home facilities.PARTICIPANTS: All 1,275,619 older adults aged 66 and older in Ontario (1,216,900 community-dwelling and 58,719 nursing home residents) who were dispensed at least one prescription from the comprehensive provincial drug plan in 2001. In Ontario, the provision of clinical pharmacy services is mandated in the nursing home setting. No comparable program exists for older adults in the community setting.MEASUREMENTS: Potentially inappropriate drug prescribing was compared between community-dwelling and nursing home residents in two categories: those to always avoid and therapies considered rarely appropriate to prescribe.RESULTS: Of the 1,275,619 adults in the cohort, nursing home residents were older (mean age+/-standard deviation=84.2+/-7.6 vs 75.0+/-6.5, P<.001), included more women (73.3% vs 57.7%, P<.001), had higher comorbidity scores (measured by the number of distinct drug therapies dispensed in the prior year (10.7+/-6.8 vs 7.2+/-5.7, P<.001) and Charlson comorbidity scores (1.4+/-1.6 vs 0.9+/-1.5, P<.001)) than community-dwelling individuals.Community-dwelling older adults were significantly more likely to be dispensed at least one drug therapy in the always avoid or rarely appropriate category than nursing home residents (3.3% vs 2.3%, P<.001). Using a logistic regression model that controlled for age, sex, and comorbidity (number of distinct drug therapies dispensed in the prior year), nursing home residents were close to half as likely to be dispensed one of these potentially inappropriate drug therapies as community-dwelling older adults (odds ratio=0.52, 95% confidence interval=0.49-0.55, P<.001).CONCLUSION: Potentially inappropriate drug therapy in the always avoid and rarely indicated categories is dispensed less often to nursing home residents than to older community-dwelling adults. Clinical pharmacist services, which are mandated in the nursing home setting, may be responsible for these differences in Ontario, Canada.

Objective To review the role of oral atypical antipsychotic drugs in the management of the behavioural and psychological symptoms of dementia (BPSD).Data sources Medline, Embase, and the Cochrane Library. Reference lists were reviewed and experts were contacted to identify additional trials.Study selection Double blind randomised controlled trials that evaluated the four oral atypical antipsychotic therapies for BPSD.Review methods Two reviewers assessed trial validity independently.Data extraction Demographics of patients, study duration, dose of antipsychotic, primary end points, adverse events.Results 77 abstracts were reviewed. Five randomised trials (1570 patients) evaluating risperidone and olanzapine were identified. The quality of trials was generally good. Most participants were in an institution (> 96%), elderly (weighted mean 82.3 years), and had Alzheimer's disease (76.3%). Trials lasted 6-12 weeks. Treatment with atypical antipsychotic drugs was superior to placebo for the primary end point in three of the five trials. Two trials comparing risperidone with haloperidol did not find any differences in the primary measures of efficacy. Adverse events were common and included extrapyramidal symptoms, somnolence, and abnormal gait.Conclusions Although atypical antipsychotic drugs are being used with increasing frequency, few randomised trials have evaluated their use for BPSD. Limited evidence supports the perception of improved efficacy and adverse event profiles compared with typical antipsychotic drugs.

OBJECTIVES: To compare the prevalence of inappropriate prescribing before and after nursing home admission and to determine which patient and physician characteristics are associated with inappropriate prescribing in the nursing home setting.DESIGN: A pre/post retrospective, cohort study.SETTING: All licensed nursing homes in Ontario, Canada.PARTICIPANTS: Nineteen thousand nine hundred eleven individuals aged 66 and older, newly admitted to nursing homes in Ontario between April 1, 1997, and March 31, 1999.MEASUREMENTS: For each patient in the cohort, a subset of the Beers criteria was used to characterize and compare the prevalence of inappropriate prescribing (as indicated by the prescription of one of 49 inappropriate drugs) before and after nursing home admission. A logistic regression model was used to study the association between inappropriate prescribing and patient and physician characteristics.RESULTS: The proportion of patients receiving a prescription for at least one inappropriate drug decreased from 25.4% before nursing home admission to 20.8% afterward (P < .001). Most patients who had been prescribed an inappropriate agent before nursing home entry had that agent discontinued after admission. The most commonly prescribed inappropriate drugs after nursing home admission were strongly anticholinergic antidepressants (6.4%) and long‐half‐life benzodiazepines (5.9%). Patients younger than 85 were more likely to receive inappropriate drug therapy (odds ratio (OR) = 1.25, 95% confidence interval (CI) = 1.15–1.35) than those aged 85 and older. Other significant predictors were having more than one prescriber (OR = 1.40, 95% CI = 1.29–1.51), having a physician aged 50 or older (OR = 1.14, 95% CI = 1.05–1.23), having a male physician (OR = 1.20, 95% CI = 1.05–1.37), having a nonspecialist physician (OR = 1.23, 95% CI = 1.01–1.49), having a nonurban physician (OR = 1.13, 95% CI = 1.03–1.24), and having a physician practicing outside the greater Ontario metropolitan area (OR = 1.31, 95% CI = 1.19–1.51).CONCLUSIONS: Although a substantial number of nursing home residents receive inappropriate drug therapy, the prevalence of inappropriate prescriptions in our cohort declined after nursing home admission despite an overall increase in drug use. Patient and physician characteristics were associated with inappropriate prescribing. Targeted interventions such as regionally based education programs or drug use restrictions may reduce the prevalence of inappropriate prescribing.