Changes in trend of antipsychotics prescription in patients treated with cholinesterase inhibitors after warnings from Italian Medicines Agency. Results from the EPIFARM-Elderly Project

Prescription Appropriateness of Drugs for Peptic Ulcer and Gastro-Esophageal Reflux Disease: Baseline Assessment in the LAPTOP-PPI Cluster Randomized Trial

Background: Drugs for peptic ulcer and gastro-esophageal reflux disease (GERD) are among the most widely prescribed, frequently without appropriate indications. This represents an important issue, as it leads to risk of adverse events for patients and unnecessary costs for National Health Service.

Aim: To assess the prescription appropriateness of drugs for GERD, in the frame of the “Evaluation of the effectiveness of a Low-cost informative intervention to improve the Appropriate PrescripTiOn of Proton PumP Inhibitors in older people in primary care: a cluster-randomized controlled study” (LAPTOP-PPI) (Clinicaltrial.gov: NCT04637750).

Methods: The appropriateness of drug prescription was assessed on data collected in administrative databases, by integrating information on concomitant medications, outpatient medical and laboratory procedures and hospital discharge diagnoses, according to the reimbursement criteria provided by the Italian Medicine Agency. We analyzed data of community-dwelling people aged 65 years and over, living in the areas of Bergamo (Northern Italy) and Caserta (Southern Italy), from July 1 to 31 December 2019.

Results: Among 380,218 patients, 175,342 (46.1%) received at least one prescription of drugs for GERD. All in all, we found that only 41.2% of patients received appropriate prescriptions.

Conclusion: Given the potential risk of adverse drug reactions, especially in older people, educational interventions should be prompted for physicians, in order to improve the quality of prescription of drugs for GERD and, in turn, avoid unfavorable health outcomes and unnecessary costs.

Measuring the Effectiveness of Safety Warnings on the Risk of Stroke in Older Antipsychotic Users: A Nationwide Cohort Study in Two Large Electronic Medical Records Databases in the United Kingdom and Italy

INTRODUCTION

Safety warnings relating to antipsychotic-associated stroke among older persons in the UK and Italy were issued. However, the impact of these safety warnings on stroke risk has not been measured to date.

OBJECTIVE

The aim of this study was to measure the change in stroke incidence after two safety warnings in both the UK and Italy.

METHOD

A cohort study was conducted using electronic medical records representative of the UK (The Health Improvement Network) and Italy (Health Search-IQVIA Health LPD), containing data on 11 million and 1 million patients, respectively. After each drug safety warning, elderly antipsychotic new initiators were propensity-score matched 1:1:1 on antipsychotic initiators before any safety warning. Stroke incidence within 6 months of antipsychotic initiation, using an intention-to-treat approach, was the main outcome.

RESULTS

In the UK and Italy, 6342 and 7587 elderly antipsychotic initiators were identified, respectively. A 42% stroke incidence reduction was seen in the UK after the first safety warning [42.3 (95% confidence interval (CI) 35.2-50.8) vs. 24.4 [95% CI 19.0-31.2] events per 1000 person-years (PYs)], while there was a 60% stroke incidence reduction after the second warning (16.9 [95% CI 12.2-23.4] events per 1000 PYs) compared to before the first warning. There was no significant reduction in stroke incidence in Italy.

CONCLUSION

Antipsychotic safety warnings were followed by a reduction in stroke incidence among older antipsychotic users in the UK, but not Italy.

Do drug-related safety warnings have the expected impact on drug therapy? A systematic review

PURPOSE

The need for drug-related safety warnings is undisputed, and their impact should also be evaluated. This systematic review investigates and assesses the impact of safety warnings on drug therapy.

METHODS

Studies published in English between January 1998 and December 2018 were searched in EMBASE and MEDLINE, complemented by manual search. Randomised controlled trials, cohort studies with a before/after component, and case-control studies were included, selected to predefined criteria, and assessed for their reporting and methodological quality.

RESULTS

Out of 7454 references identified, 72 studies were included. A total of 28/72 (39%) studies described the impact of safety warnings on drug therapy as being effective, whereas 12/72 (17%) studies did not. Further, 26/72 (36%) studies described a partial implementation of the warnings (one part of the warning had an impact on drug therapy and another did not). Unintended effects were investigated in 6/72 (8%) studies. While 34 (47%) studies examined safety warnings on psychotropic drugs using an interrupted time series (ITS) design (53%), a before/after (26%), and a time series design (21%), 38 (53%) studied other substances using an ITS design (34%), a before/after (40%), and a time series design (26%). The proportion of an effective impact on drug therapy was lower in the "psychotropic drugs" group (23%) than in the "others" group (53%).

CONCLUSION

Drug-related safety warnings induce intended and unintended effects. The included studies are of broadly varying methodological quality. To better compare their effectiveness, studies should be conducted using standardised procedures.

Antipsychotic prescribing for Alzheimer's disease and related disorders in specialized settings from 2010 to 2014 in France: a repeated cross-sectional study

BACKGROUND

Safety warnings from health authorities are currently intended to limit the use of antipsychotics (APs) in dementia-related conditions to treat neuropsychiatric symptoms, such as disturbing and/or delusional behaviors. The aim of this study is to investigate prevalence, correlates and trends of AP prescribing among people with dementia between 2010 and 2014 in the French population.

METHODS

AP prescribing and associated factors among individuals with AD, mixed dementia and vascular dementia in the French National Alzheimer Database between 2010 and 2014 were analyzed using multivariate generalized estimating equations models (n = 199,549).

RESULTS

In 2014, 7.7% of people with dementia were prescribed an AP. Compared with 2010 there was a 16% increase in AP use. Multivariate analysis showed a linear increase risk of prescription with an adjusted odds ratio (95% confidence interval) of 1.23 (1.17-1.30) in 2014 compared with 2010. Factors associated with AP prescribing were male gender, more severe cognitive decline and living in long-term care facilities. Older age and higher education were protective toward AP prescribing. The type of dementia did not have any influence on AP prescribing.

CONCLUSION

An increase in AP prescribing among individuals with dementia in French specialized settings over the last 5 years occurred despite safety warnings. This phenomenon suggests that alternative solutions for the management of behavioral and psychiatric symptoms in these populations are still urgently needed.

Regional changes in psychotropic use among Finnish persons with newly diagnosed Alzheimer's disease in 2005-2011

Objectives

To describe and compare temporal changes in prevalence and incidence of psychotropic use (antipsychotics, antidepressants and benzodiazepines and related drugs; BZDRs) in persons with newly diagnosed Alzheimer’s disease (AD) between university hospital districts of Finland during 2005–2011.

Methods

The MEDALZ study includes all community-dwellers of Finland who received a clinically verified AD diagnosis in 2005–2011 (N = 70,718). Prevalent and incident use of psychotropics among those who had received AD diagnosis less than one year ago were compared in 2005–2011.

Results

Regional differences in psychotropic use between university hospital districts were more evident in 2005 than 2011 for prevalent use of any psychotropic, antipsychotic and BZDRs and incident use of any psychotropic and antipsychotics. Regional differences in prevalent antidepressant use and incident BZDR use remained similar during the follow-up, while differences in incident antidepressant use increased during the follow-up. The prevalence of any psychotropic use in 2005 varied between 44.7–50.7% and between 45.0–47.9% in 2011. Incidence of any psychotropic use in 2005 was between 8.6–12.1% and 6.2–8.2% in 2011. In 2005, the distribution of incident psychotropic use followed a large scale spatial variation that, however, did not correspond to university hospital districts. During the study period from 2005 to 2011 the cyclic spatial variation disappeared. No sign of adjacent hospital districts being more or less closely related to each other compared to hospital districts in general was detected.

Conclusions

Except for antidepressants, regional differences in psychotropic use have mainly diminished between 2005 and 2011. Our findings highlight the importance of acknowledging regional differences in a country with relatively homogeneous healthcare system and conducting future studies assessing the reasons behind these differences.

Long-term use of antipsychotics in community-dwelling dementia patients: prevalence and profile accounting for unobservable time bias because of hospitalization

The aim of this study was to assess the prevalence of long-term antipsychotic (AP) use in community-dwelling patients with dementia considering hospitalization periods as AP exposure or not. A retrospective study was carried out from 2009 to 2012 on a PACA-Alzheimer cohort (which included 31 963 patients in 2009 and 36 442 in 2012 from 5 million inhabitants). Three groups of patients were identified according to the longest exposure to APs without interruption: nonusers, short-term users (≤3 successive months without discontinuation), and long-term users. Sensitivity analyses on hospitalization periods were carried out. The percentage of patients with at least one AP dispensing was stable over the study period (25.6% in 2009 vs. 26.5% in 2012). In 2012, 27.6% were AP long-term users. This increased to 46.7% when hospitalization periods were counted as AP exposure. In comparison with nonusers, AP users took more benzodiazepines and antidepressants. Short-term users were men [odds ratio (OR)=1.2, 95% confidence interval (CI) (1.1-1.3)] older than 85 years old [OR=1.2, 95% CI (1.1-1.2)]. Long-term users were more exposed to benzodiazepines [OR=1.2, 95% CI (1.1-1.4)]. This study showed that long-term use of AP remained frequent in community-dwelling patients with dementia. It also showed that the prevalence of long-term users almost doubled when hospitalization periods were counted as AP exposure. This underlines the need to consider hospitalization periods when assessing medication exposure in populations with frequent periods of hospitalization.

The Effect of Safety Warnings on Antipsychotic Drug Prescribing in Elderly Persons with Dementia in the United Kingdom and Italy: A Population-Based Study

BACKGROUND

Antipsychotic (AP) drugs are commonly used to manage the behavioural symptoms of dementia. Nevertheless, international (i.e. the European Medicines Agency in Europe) and national (i.e. the Medicines and Healthcare products Regulatory Agency in the UK and the Italian Drug Agency) regulatory agencies issued safety warnings against AP use in dementia in 2004 and 2009.

OBJECTIVE

The aim of this study is to investigate the short- and long-term impact of safety warnings on the use of APs in UK and Italian persons with dementia using two nationwide databases: The Health Improvement Network (THIN) from the UK and the Health Search Database-Cegedim-Strategic Data-Longitudinal Patient Database (HSD-CSD-LPD) from Italy.

METHODS

We calculated the overall quarterly prevalence of AP use by class and by individual drug in persons with dementia aged ≥65 years and used generalized linear models to explore the effect of the safety warnings.

RESULTS

We identified 58,497 and 10,857 individuals aged ≥65 years with dementia from the THIN and HSD-CSD-LPD databases, respectively, over the period 2000-2012. After the 2004 warnings, the use of atypical APs decreased, whereas the use of conventional APs increased, in Italy and the UK until 2009. However, the trend for APs individually showed that the use of risperidone/olanzapine decreased, whereas the use of quetiapine increased in both countries. After the 2009 warnings (until 2012), the use of atypical and conventional APs decreased in the UK (from 11 to 9 and 5 to 3 %, respectively), but such use increased in Italy (from 11 to 18 and 9 to 14 %, respectively).

CONCLUSION

The 2004 warnings led to a reduction in the use of olanzapine and risperidone and increased the use of quetiapine/conventional APs in both countries. From 2009, the use of APs decreased in persons with dementia in the UK but not in Italy. Possible reasons for the difference in AP use between the two countries include a more proactive approach towards reducing the use of APs in the UK than in Italy.

Trends in use of psychotropic medications among patients treated with cholinesterase inhibitors in Japan from 2002 to 2010

BACKGROUND

We aimed to examine trends in the use of psychotropic medications among elderly outpatients with dementia in Japan between 2002 and 2010.

METHODS

We used data from the 2002-2010 Survey of Medical Care Activities in Public Health Insurance (SMCA-PHI), a nationally representative cross-sectional survey of claims data for the month of June in every year. We included ambulatory care visits by patients aged 65 years or older who were prescribed cholinesterase inhibitors (n = 15,591), and identified use of any psychotropic medications during the survey month.

RESULTS

In 2008–2010, the most prevalently prescribed psychotropic medications to patients with dementia were sedatives-hypnotics (27.3%), antipsychotics (21.3%), antidepressants (11.4%), and mood-stabilizers(2.8%). Between 2002–2004 and 2008–2010, use of second-generation antipsychotics increased from 4.9%to 11.2%, while use of first-generation antipsychotics decreased from 17.4% to 12.1% [corrected].These numbers resulted in a 1.1-fold increase in the adjusted prevalence of the overall use of antipsychotics. Quetiapine and risperidone use showed a 4.8- and 1.8-fold increase, respectively, while haloperidol use showed a 2.3-fold decrease.

CONCLUSIONS

Despite safety warnings against the use of antipsychotics for patients with dementia in several countries, our study revealed a slight increase in the extensive use of off-label antipsychotics over time in Japan. This finding indicates an urgent need for evaluation of the efficacy of antipsychotics for the approved treatment of severe agitation, aggression, and psychosis associated with dementia. Moreover, psychosocial interventions and antipsychotic withdrawal strategies are needed in order to reduce the overall prevalence of antipsychotic use.

High prevalence of psychotropic drug use among persons with and without Alzheimer's disease in Finnish nationwide cohort

Psychotropic drugs are used for treatment of behavioral and psychological symptoms of dementia (BPSD) although they are associated with serious adverse drug events. Objective of our study was to investigate prevalence of psychotropic drug use one year after diagnoses of Alzheimer's disease (AD), to compare prevalence to persons without AD and to assess changes in prevalence over time. Data from the MEDALZ (Medication use and Alzheimer's disease) cohort was utilized in the study including all 69,080 community-dwelling persons with new diagnosis of AD during years 2005-2011 in Finland. Four age-, gender- and region of residence-matched persons without AD were identified for each case. Register-based data included prescription drug purchases and comorbidities from Special Reimbursement Register. Annual prevalence of psychotropic drug use one year after diagnosis was determined for each person. Psychotropic drugs were used by 53% of persons with AD compared with 33% of persons without AD during one year after diagnoses. Persons with AD were six times more likely to use antipsychotics and three times more likely to use antidepressants whereas benzodiazepine and related drug (BZDR) use was comparable between persons with and without AD. According to year of AD diagnoses during 2005-2011, antipsychotic use increased from 18% to 20% (p<0.0001) and BZDR use declined from 31% to 26% (p<0.0001) among persons with AD. Widespread utilization of psychotropic drugs was observed among persons with AD. Despite safety warnings of antipsychotic use for BPSD, antipsychotic use increased from 2005 to 2011 among newly diagnosed persons with AD in Finland.

Electrocardiographic monitoring for new prescriptions of quetiapine co-prescribed with acetylcholinesterase inhibitors or memantine from 2005 to 2009. A population study on community-dwelling older people in Italy

PURPOSE

The aims of this study are to analyse, in community-dwelling people aged 65+ living in Italy's Lombardy Region, electrocardiographic (ECG) monitoring for new users of the atypical antipsychotic quetiapine co-prescribed with acetylcholinesterase inhibitors (AChEIs) or memantine and to find independent predictors of ECG monitoring before and after the starting of this prescription.

METHODS

The Lombardy Region's administrative health database was used to retrieve prescriptions of ECG exams as well as prevalence rates of subjects aged 65+ who were prescribed such psychotropic drugs from 2005 to 2009. Multivariable analyses were adjusted for age, sex, number of drugs, treatment with beta-blockers, digoxin, verapamil or diltiazem, any antiarrhythmic drug and antidepressants.

RESULTS

Overall 2,623 community-dwelling older people started therapy with quetiapine, co-prescribed with AChEIs or memantine, during these 5 years. At least one ECG was performed in 714 cases (27.2 %) in the 6 months before-and in 398 cases (15.2 %) within 3 months after-the starting of this prescription. ECG monitoring was performed both before and after starting quetiapine in only 160 cases (6.1 %). At multivariable analyses, number of drugs taken, beta-blocker and antiarrhythmic drug use were found to be independent correlates of ECG monitoring whereas female sex was associated with a lower probability of receiving an ECG within 3 months after the initiation of quetiapine (odds ratio 0.78, 95 % CI 0.62-0.98).

CONCLUSIONS

ECG monitoring for new prescriptions of quetiapine in older people suffering from behavioural and psychological symptoms in dementia was actually performed infrequently, independently of the age of drug users, especially in women. Our results support the need for greater awareness within the medical community of the importance of such ECG monitoring.

Trends in use of antipsychotics in elderly patients with dementia: Impact of national safety warnings

Based on evidence of an increased risk of death, drug agencies issued safety warnings about the use of second generation antipsychotics (SGAs) in the elderly with dementia. The French agency issued a warning in 2004. which was extended to all antipsychotics in 2008. Little is known about the impact of these warnings on use. We conducted a quasi-experimental study (interrupted time-series) in France, for 2003-2011, including subjects aged ≥65 with dementia and subjects aged ≥65 without dementia in the EGB database (1/97th representative random sample of claims from the main Health Insurance scheme). Outcomes were monthly rates of use of antipsychotics (by class and agent) and of five comparison drug classes (antidepressants, benzodiazepines, dermatologicals, antidiabetics, antiasthmatics). Trends were analyzed by joinpoint regression, impact of warnings by linear segmented regression. In patients with dementia (n=7169), there was a 40% reduction in antipsychotic use from 14.2% in 2003 to 10.2% in 2011. The reduction began before 2004 and was unaffected by the warnings. Use of first generation antipsychotics declined over the period, while use of SGAs increased and leveled off from 2007. Use of the five comparison drug classes increased on the period. In subjects without dementia (n=91,942), rates of overall antipsychotic use decreased from 2.3% in 2003 to 1.8% in 2011 with no effect of the warnings. Meanwhile, use of SGAs continuously increased from 0.37% to 0.64%. Antipsychotic use decreased in the elderly between 2003 and 2011, especially in dementia. The timing of the decrease, however, did not coincide with safety warnings.

Predictors of mortality in atypical antipsychotic-treated community-dwelling elderly patients with behavioural and psychological symptoms of dementia: a prospective population-based cohort study from Italy

PURPOSE

To evaluate the effect of a broad range of covariates on the survival of a real-life long-term follow-up cohort of community-dwelling patients with behavioural and psychological symptoms of dementia who were new users of atypical antipsychotic medications (APMs).

METHODS

This was a prospective cohort study of 1,618 subjects aged ≥65 years with dementia and BPSD ("behavioural and psychological symptoms of dementia") who were new users of atypical APMs and registered in a Dementia Evaluation Unit of Campania Region (Italy) from September 2006 to March 2010. The potential of baseline features to predict mortality was assessed with the Cox proportional hazards model.

RESULTS

The average follow-up was 309 days. Of the 1,618 new users of atypical antipsychotics, 9.3 % experienced at least one adverse event, including death (5.1 %), drug therapeutic failure (3.0 %), extrapyramidal symptoms (0.5 %) and stroke (0.2 %). The crude all-cause mortality rate was 6.0 per 100 person-years [95 % confidence interval (CI) 4.8-7.4]; the rate was higher in patients aged >85 years (9.0 per 100 person-years, 95 % CI 6.4-12.7) and among male patients (7.5 per 100 person-years, 95% CI 5.3-10.6). In the multivariate analysis, only age was associated to all-cause mortality [hazard ratio (HR) 1.1; 95 % CI 1.0-1.1 and HR 1.4; 95 % CI: 0.9-2.2, respectively). In contrast, hallucination (HR 0.4; 95 % CI 0.2-0.6) and dosage change (HR 0.4; 95 % CI 0.2-0.78) were significantly associated with a lower risk of all-cause mortality.

CONCLUSIONS

Among our patient cohort, the mortality rate of patients with BPSD receiving long-term treatment with atypical APMs was lower than that reported in other studies, and only age was found to be significant predictor factor of mortality.

Validation of healthcare administrative data for the diagnosis of epilepsy

BACKGROUND

Administrative databases have become an important tool to monitor diseases. Patients with epilepsy could be traced using disease-specific codes and prescriptions, but formal validation is required to obtain an accurate case definition. The aim of the study was to correlate administrative data on epilepsy with an independent source of patients with epilepsy in a district of Lombardy, Northern Italy, from 2000 to 2008.

METHODS

Data of nearly 320 600 inhabitants in the district of Lecco collected from the Drug Administrative Database of the Lombardy Region were analysed. Among them were included patients who fulfilled the International Classification of Diseases 9 (ICD-9) codes and/or the disease-specific exemption code for epilepsy and those who had at least one EEG record and took antiepileptic drugs (AEDs) as monotherapy or in variable combinations. To ascertain epilepsy cases, 11 general practitioners (GPs) with 15 728 affiliates were contacted. Multiple versions of the diagnostic algorithm were developed using different logistic regression models and all combinations of the four independent variables.

RESULTS

Among the GP affiliates, 71 (4.5/1000) had a gold standard diagnosis of epilepsy. The best and most conservative algorithm included EEG and selected treatment schedules and identified 61/71 patients with epilepsy (sensitivity 85.9%, CI 76.0% to 92.2%) and 15 623/15 657 patients without epilepsy (specificity 99.8%,CI 99.7% to 99.8%). The positive and negative predictive values were 64.2% and 99.9%. Sensitivity (86.7%) and the positive predictive value (68.4%) increased only slightly when patients with single seizures were included.

CONCLUSIONS

A diagnostic algorithm including EEG and selected treatment schedules is only moderately sensitive for the detection of epilepsy and seizures. These findings apply only to the Northern Italian scenario.

Impact of safety warnings on antipsychotic prescriptions in dementia: nothing has changed but the years and the substances

Dementia patients suffering from behavioral and psychological symptoms (BPSD) are often treated with antipsychotics. Trial results document an increased risk for serious adverse events and mortality in dementia patients taking these agents. Furthermore, the efficacy of treating BPSD with antipsychotics seems to be only modest. Using data of a German statutory health insurance company, we examined prescription trends of antipsychotics in prevalent dementia patients in the context of official warnings. The study period is 2004-2009. We studied trends in demographics, age and sex, as well as need of care and the intake of typical and atypical antipsychotics. Seeking for linear trends adjusted for age, sex and level of care between 2004 and 2009, we obtained p-values from a multivariate logistic regression. Prescription volumes were calculated by number of packages as well as defined daily doses (DDDs) using multiple linear regressions for trends in prescriptions amount. We included 3460-8042 patients per year (mean age 80 years). The prescription prevalence of antipsychotics decreased from 35.5% in 2004 to 32.5% in 2009 (multivariate analysis for linear trend: p=0.1645). Overall prescriptions for typical antipsychotics decreased (from 27.2% in 2004 to 23.0% in 2009, p<0.0001) and prescriptions for atypical antipsychotics increased from 17.1% to 18.9% (p<0.0001). The mean DDD per treated patient increased from 80.5 to 91.2 (2004-2009; p=0.0047). Our findings imply that warnings of international drug authorities and manufacturers against adverse drug events in dementia patients receiving antipsychotics did not impact overall prescription behavior.

Antipsychotics prescription and cerebrovascular events in Italian older persons

Meta-analyses have found conflicting evidence on the link between antipsychotics and cerebrovascular events (CVEs). The primary aim of this study was to evaluate the association between any antipsychotic prescription and CVEs in Italian elderly; second, to compare the effect of typical and atypical antipsychotics on CVEs; and third, to investigate the effect of antipsychotics on CVEs in the subgroup of persons coprescribed with acetylcholinesterase inhibitors (AChEIs). Administrative claims from community-dwelling people aged 65 to 94 years living in Northern Italy were analyzed using a retrospective case-control design, from 2003 to 2005. The primary outcome measure was a hospital discharge diagnosis of CVEs during 2005. Four age-, sex-, and local health unit-matched control subjects were identified for each case. Antihypertensive drugs, anticoagulants, platelet inhibitors, antidiabetic drugs, lipid-lowering drugs, and AChEI were used as covariates in conditional logistic regression models testing the odds ratio (OR) for CVEs due to antipsychotics use. Three thousand eight hundred fifty-five cases of CVEs were identified and matched with 15,420 control subjects. In multiadjusted models, the association of any antipsychotics, typical or atypical with CVEs, was not significant. When antipsychotics were categorized according to the number of boxes prescribed during the observational period, being prescribed with at least 19 boxes of typical antipsychotics was significantly associated with CVEs (OR, 2.4; 95% confidence interval, 1.08-5.5). An interaction was found between any antipsychotic and AChEI coprescription on CVEs (OR, 0.46; 95% confidence interval, 0.23-0.92). In conclusion, only typical antipsychotics were associated with an increased odd of CVEs, but the association was duration dependent. Persons prescribed simultaneously with AChEI and antipsychotics may be at a lower risk of CVEs.

Geographical differences in the prevalence of chronic polypharmacy in older people: eleven years of the EPIFARM-Elderly Project

PURPOSE

To compare the geographical differences in the prevalence of chronic polypharmacy in community-dwelling older people over 11 years.

METHODS

This study analyzed nearly two million patients aged 65-94 years recorded in the Drug Administrative Database of the Lombardy Region (Northern Italy) from 2000 to 2010. Chronic polypharmacy was defined as taking five or more drugs in 1 month for at least 6 months (consecutive or not) in a year.

RESULTS

There was a significant spatial autocorrelation that increased at the municipality level from 2000 (Moran's I Index = 0.26, z score = 16.91, p < 0.0001) to 2010 (Moran's I Index = 0.36, z score = 23.78, p < 0.0001). Clusters of high (Z(G) > 1.96) and low (Z(G) < -1.96) prevalence rates of chronic polypharmacy were found and were not influenced by age. Chronic polypharmacy weakly correlated with hospital admission (2000: ρ = 0.08, p = 0.0032; 2005: ρ = 0.11, p < 0.0001; 2010: ρ = 0.18, p < 0.0001), but not with mortality.

CONCLUSIONS

There were geographical differences in the prevalence of older people with chronic polypharmacy that were only partly explained by health indicators. Targeted activities on prescription practice to ensure that the prescribing of chronic polypharmacy is appropriate are required.