Geographical differences in the prevalence of chronic polypharmacy in older people: eleven years of the EPIFARM-Elderly Project
- 507 Downloads
To compare the geographical differences in the prevalence of chronic polypharmacy in community-dwelling older people over 11 years.
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.
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.
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.
KeywordsOlder people Chronic polypharmacy Geographical difference Clusters
Conflict of interest
- 13.Gnjidic D, Hilmer SN, Blyth FM, Naganathan V, Waite L, Seibel MJ, McLachlan AJ, Cumming RG, Handelsman DJ, Le Couteur DG (2012) Polypharmacy cutoff and outcomes: five or more medicines were used to identify community-dwelling older men at risk of different adverse outcomes. J Clin Epidemiol 65(9):989–995PubMedCrossRefGoogle Scholar
- 16.Patterson SM, Hughes CM, Kerse N, Cardwell C, Bradley M (2012) Interventions to improve appropriate polypharmacy for older people. (Review). Cochrane Database Syst Rev (5)Google Scholar
- 19.Nobili A, Franchi C, Pasina L, Tettamanti M, Baviera M, Monesi L, Roncaglioni C, Riva E, Lucca U, Bortolotti A, Fortino I, Merlino L (2011) Drug utilization and polypharmacy in an Italian elderly population: the EPIFARM-Elderly Project. Pharmacoepidemiol Drug Saf 20:488–496PubMedCrossRefGoogle Scholar
- 22.Franchi C, Tettamanti M, Marengoni A, Bonometti F, Pasina L, Cortesi L, Fortino I, Bortolotti A, Merlino L, Lucca U, Riva E, Nobili A (2012) Changes in trend of antipsychotics prescription in patients treated with cholinesterase inhibitors after warnings from Italian Medicines Agency. Results from the EPIFARM-Elderly Project. Eur Neuropsychopharmacol 22(8):569–577PubMedCrossRefGoogle Scholar
- 23.WHO Collaborating Centre for Drug Statistics Methodology. The Anatomical Therapeutic Chemical (ATC) classification. About the ATC/DDD system. http://www.whocc.no/atcddd/. Accessed 15 June 2012
- 24.Istituto Nazionale di Statistica (ISTAT). http://www.istat.it/it/archivio/44523. Accessed 15 July 2012
- 25.Getis A, Ord JK (1992) The analysis of spatial association by use of distance statistics. Geogr Anal 24:3Google Scholar
- 31.Progetto ARNO: Rapporto sul profilo prescrittivo della popolazione anziana. Rapporto 2001. CINECA. Centauro Editore, Bologna 2002Google Scholar