Individuals at risk of beta-blocker discontinuation: a cohort study in 19,177 Chinese patients

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.

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.

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.

Patients who were prescribed beta-blockers with these associated factors should be monitored more closely for antihypertensive drug adherence.