title: Gender differences, polypharmacy, and potential pharmacological interactions in the elderly.
abstract: OBJECTIVE
  This study aims to analyze pharmacological interactions among drugs taken by elderly patients and their age and gender differences in a population from Porto Alegre, Brazil.
  
  
  METHODS
  We retrospectively analyzed the database provided by the Institute of Geriatric and Gerontology, Porto Alegre, Brazil. The database was composed of 438 elderly and includes information about the patients' disease, therapy regimens, utilized drugs. All drugs reported by the elderly patients were classified using the Anatomical Therapeutic and Chemical Classification System. The drug-drug interactions and their severity were assessed using the Micromedex® Healthcare Series.
  
  
  RESULTS
  Of the 438 elderly patients in the data base, 376 (85.8%) used pharmacotherapy, 274 were female, and 90.4% of females used drugs. The average number of drugs used by each individual younger than 80 years was 3.2±2.6. Women younger than 80 years old used more drugs than men in the same age group whereas men older than 80 years increased their use of drugs in relation to other age groups. Therefore, 32.6% of men and 49.2% of women described at least one interaction, and 8.1% of men and 10.6% of women described four or more potential drug-drug interactions. Two-thirds of drug-drug interactions were moderate in both genders, and most of them involved angiotensin-converting enzyme inhibitor, non-steroidal anti-inflammatory, loop and thiazide diuretics, and β-blockers.
  
  
  CONCLUSIONS
  Elderly patients should be closely monitored, based on drug class, gender, age group and nutritional status.
authors.affiliation: Instituto de Geriatria e Gerontologia, Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), Porto Alegre, RS, Brazil.
authors.forename: Carina Duarte
authors.initials: CD
authors.lastname: Venturini
authors.forename: Paula
authors.initials: P
authors.lastname: Engroff
authors.forename: Luísa Scheer
authors.initials: LS
authors.lastname: Ely
authors.forename: Luísa Faria de Araújo
authors.initials: LF
authors.lastname: Zago
authors.forename: Guilherme
authors.initials: G
authors.lastname: Schroeter
authors.forename: Irenio
authors.initials: I
authors.lastname: Gomes
authors.forename: Geraldo Attilio
authors.initials: GA
authors.lastname: De Carli
authors.forename: Fernanda Bueno
authors.initials: FB
authors.lastname: Morrone
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D001938:Brazil; D004347:Drug Interactions / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019338:Polypharmacy; D012189:Retrospective Studies; D017678:Sex Distribution
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