Adherence to antihypertensive medications and cardiovascular morbidity among newly diagnosed hypertensive patients

Circulation. 2009 Oct 20;120(16):1598-605. doi: 10.1161/CIRCULATIONAHA.108.830299. Epub 2009 Oct 5.


Background: Nonadherence to antihypertensive treatment is a common problem in cardiovascular prevention and may influence prognosis. We explored predictors of adherence to antihypertensive treatment and the association of adherence with acute cardiovascular events.

Methods and results: Using data obtained from 400 Italian primary care physicians providing information to the Health Search/Thales Database, we selected 18,806 newly diagnosed hypertensive patients >or=35 years of age during the years 2000 to 2001. Subjects included were newly treated for hypertension and initially free of cardiovascular diseases. Patient adherence was subdivided a priori into 3 categories-high (proportion of days covered, >or=80%), intermediate (proportion of days covered, 40% to 79%), and low (proportion of days covered, <or=40%)-and compared with the long-term occurrence of acute cardiovascular events through the use of multivariable models adjusted for demographic factors, comorbidities, and concomitant drug use. At baseline (ie, 6 months after index diagnosis), 8.1%, 40.5%, and 51.4% of patients were classified as having high, intermediate, and low adherence levels, respectively. Multiple drug treatment (odds ratio, 1.62; 95% CI, 1.43 to 1.83), dyslipidemia (odds ratio, 1.52; 95% CI, 1.24 to 1.87), diabetes mellitus (odds ratio, 1.40; 95% CI, 1.15 to 1.71), obesity (odds ratio, 1.50; 95% CI, 1.26 to 1.78), and antihypertensive combination therapy (odds ratio, 1.29; 95% CI, 1.15 to 1.45) were significantly (P<0.001) associated with high adherence to antihypertensive treatment. Compared with their low-adherence counterparts, only high adherers reported a significantly decreased risk of acute cardiovascular events (hazard ratio, 0.62; 95% CI, 0.40 to 0.96; P=0.032).

Conclusions: The long-term reduction of acute cardiovascular events associated with high adherence to antihypertensive treatment underscores its importance in assessments of the beneficial effects of evidence-based therapies in the population. An effort focused on early antihypertensive treatment initiation and adherence is likely to provide major benefits.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Antihypertensive Agents / therapeutic use*
  • Cardiovascular Diseases / epidemiology
  • Cardiovascular Diseases / etiology
  • Cardiovascular Diseases / prevention & control*
  • Cohort Studies
  • Databases, Factual
  • Diabetes Complications
  • Drug Therapy, Combination
  • Dyslipidemias / complications
  • Female
  • Humans
  • Hypertension / complications
  • Hypertension / drug therapy*
  • Hypertension / psychology*
  • Incidence
  • Male
  • Middle Aged
  • Obesity / complications
  • Patient Compliance*


  • Antihypertensive Agents