title: Short-acting nifedipine and risk of stroke in elderly hypertensive patients.
abstract: OBJECTIVE
  Short-acting nifedipine is frequently prescribed in elderly hypertensive patients, despite warnings of possible harmful cardiovascular effects. We conducted a case-crossover study to estimate the risk of stroke episodes associated with use of short-acting nifedipine in elderly hypertensive patients.
  
  
  METHODS
  We used the Korea Health Insurance Review & Assessment Service database. Cases included elderly hypertensive patients with hospitalization or emergency department visits for first stroke (International Classification of Diseases-10, I60-I64) between July 1, 2005, and June 30, 2006. Patients with prior stroke-related hospital admission or any visit related to TIA were excluded. Exposure to a short-acting nifedipine formulation was assessed within 7 days before the incident stroke episode (case period) and within a 7-day period preceding 60 days before the episode (control period). Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated by conditional logistic regression, with adjusting for antihypertensives, anticoagulants, antiplatelet agents, and pneumonia.
  
  
  RESULTS
  A total of 16,069 stroke patients with a mean (±SD) age of 68.3 (±2.1) years were studied, of whom 8,573 (53.3%) were female. Short-acting nifedipine was prescribed at least once to 301 (1.9%) patients during the case period. An increased risk of stroke associated with use of short-acting nifedipine within 7 days (adjusted OR 2.56; 95% CI 1.96-3.37) was observed. Patients who were newly prescribed nifedipine within the recent 7 days showed an OR of 4.17 (95% CI 2.93-5.93) compared with nonusers.
  
  
  CONCLUSIONS
  Use of short-acting nifedipine was associated with increased risk of stroke occurrence in elderly hypertensive patients.
authors.affiliation: Department of Preventive Medicine, Seoul National University College of Medicine, 103 Daehakno, Chongno-Gu, Seoul 110-799, Korea.
authors.forename: S-Y
authors.initials: SY
authors.lastname: Jung
authors.forename: N-K
authors.initials: NK
authors.lastname: Choi
authors.forename: J-Y
authors.initials: JY
authors.lastname: Kim
authors.forename: Y
authors.initials: Y
authors.lastname: Chang
authors.forename: H J
authors.initials: HJ
authors.lastname: Song
authors.forename: J
authors.initials: J
authors.lastname: Lee
authors.forename: B-J
authors.initials: BJ
authors.lastname: Park
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016001:Confidence Intervals; D018592:Cross-Over Studies; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D009313:National Health Programs / Q000706:statistics & numerical data; D009543:Nifedipine / Q000627:therapeutic use*; D016017:Odds Ratio; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D012307:Risk Factors; D020521:Stroke / Q000188:drug therapy* / Q000453:epidemiology*; D013997:Time Factors; D014665:Vasodilator Agents / Q000627:therapeutic use*
chemical_list: D014665:Vasodilator Agents; D009543:Nifedipine