title: Individuals at risk of beta-blocker discontinuation: a cohort study in 19,177 Chinese patients.
abstract: OBJECTIVE
  This cohort study evaluated the factors associated with discontinuation of antihypertensive pharmacotherapy among Chinese patients who were prescribed beta-blockers. We tested the hypothesis that patients' age, gender, socioeconomic status, clinical settings and the number of comorbidities were significantly associated with the discontinuation of beta-blockers.
  
  
  METHODS
  From a validated clinical database we included all adult patients 18 years or older who were prescribed a beta-blocker in any government primary care clinic in one large territory of Hong Kong during 01 January 2004-30 June 2007. We evaluated the cumulative incidence of drug discontinuation within 180 days of the prescriptions and the factors associated with discontinuation of beta-blockers by multivariable regression analysis.
  
  
  RESULTS
  From a total of 19,177 eligible patients (mean age = 59.1 years), 20.8% discontinued their medication. Younger patients [aged <50 years; adjusted odds ratios (aOR) 0.41-0.52 for patients aged >or=50 years; p < 0.001], female gender (aOR 0.87 for males, p = 0.001), fee-waivers (aOR 0.78 for fee-payers, p < 0.001), attendances in family medicine specialist clinics (FMSC) (aOR 1.49, p < 0.001) and staff clinics (aOR 2.32, p < 0.001), residence in more urbanized areas (aOR 0.80 for North District, p < 0.001), new visits (aOR 0.55 for follow-up visits, p < 0.001) and absence of concomitant comorbidities (aOR 0.60 for one comorbidity, p < 0.001; aOR 0.56 for two comorbidities, p = 0.002) were positively associated with drug discontinuation.
  
  
  CONCLUSIONS
  Patients who were prescribed beta-blockers with these associated factors should be monitored more closely for antihypertensive drug adherence.
authors.affiliation: School of Public Health and Primary Care, Faculty of Medicine, Chinese University of Hong Kong, New Territories, Hong Kong.
authors.forename: Martin C S
authors.initials: MC
authors.lastname: Wong
authors.forename: Johnny Y
authors.initials: JY
authors.lastname: Jiang
authors.forename: Xuefen
authors.initials: X
authors.lastname: Su
authors.forename: Haoxiang
authors.initials: H
authors.lastname: Wang
authors.forename: Jin Ling
authors.initials: JL
authors.lastname: Tang
authors.forename: Sian M
authors.initials: SM
authors.lastname: Griffiths
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000959:Antihypertensive Agents / Q000008:administration & dosage*; D044466:Asian People / Q000706:statistics & numerical data*; D015331:Cohort Studies; D004334:Drug Administration Schedule; D005260:Female; D006723:Hong Kong / Q000453:epidemiology; D006801:Humans; D006973:Hypertension / Q000401:mortality* / Q000517:prevention & control*; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D018570:Risk Assessment; D012307:Risk Factors; D016019:Survival Analysis; D015996:Survival Rate; D028761:Withholding Treatment / Q000706:statistics & numerical data*
chemical_list: D000319:Adrenergic beta-Antagonists; D000959:Antihypertensive Agents