title: Ageing with HIV: medication use and risk for potential drug-drug interactions.
abstract: OBJECTIVE
  To compare the use of co-medication, the potential drug-drug interactions (PDDIs) and the effect on antiretroviral therapy (ART) tolerability and efficacy in HIV-infected individuals according to age, ≥ 50 years or <50 years.
  
  
  METHODS
  All ART-treated participants were prospectively included once during a follow-up visit of the Swiss HIV Cohort Study. Information on any current medication was obtained by participant self-report and medical prescription history. The complete treatment was subsequently screened for PDDIs using a customized version of the Liverpool drug interaction database.
  
  
  RESULTS
  Drug prescriptions were analysed for 1497 HIV-infected individuals: 477 age ≥ 50 and 1020 age <50. Older patients were more likely to receive one or more co-medications compared with younger patients (82% versus 61%; P < 0.001) and thus had more frequent PDDIs (51% versus 35%; P < 0.001). Furthermore, older patients tended to use a higher number of co-medications and certain therapeutic drug classes more often, such as cardiovascular drugs (53% versus 19%; P < 0.001), gastrointestinal medications (10% versus 6%; P = 0.004) and hormonal agents (6% versus 3%; P = 0.04). PDDIs with ART occurred mainly with cardiovascular drugs (27%), CNS agents (22%) and methadone (6%) in older patients and with CNS agents (27%), methadone (15%) and cardiovascular drugs (11%) in younger patients. The response to ART did not differ between the two groups.
  
  
  CONCLUSIONS
  The risk for PDDIs with ART increased in older patients who take more drugs than their younger HIV-infected counterparts. However, medication use in older and younger patients did not differ in terms of effect on antiretroviral tolerability and response.
authors.affiliation: Division of Infectious Diseases and Hospital Epidemiology, University Hospital Basel, Basel, Switzerland. marzolinic@uhbs.ch
authors.forename: Catia
authors.initials: C
authors.lastname: Marzolini
authors.forename: David
authors.initials: D
authors.lastname: Back
authors.forename: Rainer
authors.initials: R
authors.lastname: Weber
authors.forename: Hansjakob
authors.initials: H
authors.lastname: Furrer
authors.forename: Matthias
authors.initials: M
authors.lastname: Cavassini
authors.forename: Alexandra
authors.initials: A
authors.lastname: Calmy
authors.forename: Pietro
authors.initials: P
authors.lastname: Vernazza
authors.forename: Enos
authors.initials: E
authors.lastname: Bernasconi
authors.forename: Saye
authors.initials: S
authors.lastname: Khoo
authors.forename: Manuel
authors.initials: M
authors.lastname: Battegay
authors.forename: Luigia
authors.initials: L
authors.lastname: Elzi
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D019380:Anti-HIV Agents / Q000009:adverse effects* / Q000627:therapeutic use*; D023241:Antiretroviral Therapy, Highly Active / Q000009:adverse effects*; D002317:Cardiovascular Agents / Q000009:adverse effects / Q000627:therapeutic use; D002491:Central Nervous System Agents / Q000009:adverse effects / Q000627:therapeutic use; D015331:Cohort Studies; D004347:Drug Interactions; D011307:Drug Prescriptions / Q000706:statistics & numerical data; D005260:Female; D005500:Follow-Up Studies; D005765:Gastrointestinal Agents / Q000009:adverse effects / Q000627:therapeutic use; D015658:HIV Infections / Q000150:complications* / Q000188:drug therapy* / Q000821:virology; D006728:Hormones / Q000009:adverse effects / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008691:Methadone / Q000009:adverse effects / Q000627:therapeutic use; D008875:Middle Aged; D009294:Narcotics / Q000009:adverse effects / Q000627:therapeutic use; D012959:Socioeconomic Factors; D015819:Substance Abuse, Intravenous / Q000150:complications; D019966:Substance-Related Disorders / Q000150:complications; D013557:Switzerland / Q000453:epidemiology
chemical_list: D019380:Anti-HIV Agents; D002317:Cardiovascular Agents; D002491:Central Nervous System Agents; D005765:Gastrointestinal Agents; D006728:Hormones; D009294:Narcotics; D008691:Methadone