title: Multicenter cluster-randomized trial of a multifactorial intervention to improve antihypertensive medication adherence and blood pressure control among patients at high cardiovascular risk (the COM99 study).
abstract: BACKGROUND
  Medication nonadherence is common and results in preventable disease complications. This study assessed the effectiveness of a multifactorial intervention to improve both medication adherence and blood pressure control and to reduce cardiovascular events.
  
  
  RESULTS
  In this multicenter, cluster-randomized trial, physicians from hospital-based hypertension clinics and primary care centers across Spain were randomized to receive and provide the intervention to their high-risk patients. Eligible patients were ≥ 50 years of age, had uncontrolled hypertension, and had an estimated 10-year cardiovascular risk greater than 30%. Physicians randomized to the intervention group counted patients' pills, designated a family member to support adherence behavior, and provided educational information to patients. The primary outcome was blood pressure control at 6 months. Secondary outcomes included both medication adherence and a composite end point of all-cause mortality and cardiovascular-related hospitalizations. Seventy-nine physicians and 877 patients participated in the trial. The mean duration of follow-up was 39 months. Intervention patients were less likely to have an uncontrolled systolic blood pressure (odds ratio 0.62, 95% confidence interval 0.50 to 0.78) and were more likely to be adherent (odds ratio 1.91, 95% confidence interval 1.19 to 3.05) than control group patients at 6 months. After 5 years, 16% of the patients in the intervention group and 19% in the control group met the composite end point (hazard ratio 0.97, 95% confidence interval 0.67 to 1.39).
  
  
  CONCLUSIONS
  A multifactorial intervention to improve adherence to antihypertensive medication was effective in improving both adherence and blood pressure control, but it did not appear to improve long-term cardiovascular events.
authors.affiliation: Center for Health Services Research, Henry Ford Hospital, One Ford Place 3A, Detroit, MI, USA. mpladev1@hfhs.org
authors.forename: Manel
authors.initials: M
authors.lastname: Pladevall
authors.forename: Carlos
authors.initials: C
authors.lastname: Brotons
authors.forename: Rafael
authors.initials: R
authors.lastname: Gabriel
authors.forename: Anna
authors.initials: A
authors.lastname: Arnau
authors.forename: Carmen
authors.initials: C
authors.lastname: Suarez
authors.forename: Mariano
authors.initials: M
authors.lastname: de la Figuera
authors.forename: Emilio
authors.initials: E
authors.lastname: Marquez
authors.forename: Antonio
authors.initials: A
authors.lastname: Coca
authors.forename: Javier
authors.initials: J
authors.lastname: Sobrino
authors.forename: George
authors.initials: G
authors.lastname: Divine
authors.forename: Michele
authors.initials: M
authors.lastname: Heisler
authors.forename: L Keoki
authors.initials: LK
authors.lastname: Williams
mesh_terms: D000328:Adult; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D001794:Blood Pressure / Q000502:physiology*; D002318:Cardiovascular Diseases / Q000453:epidemiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000503:physiopathology; D053208:Kaplan-Meier Estimate; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D010349:Patient Compliance; D010353:Patient Education as Topic; D012307:Risk Factors; D013030:Spain; D016896:Treatment Outcome
chemical_list: D000959:Antihypertensive Agents
references.citation: Arch Intern Med. 2004 Apr 12;164(7):722-32
references.pmid: 15078641
references.citation: Am J Hypertens. 2008 Oct;21(10):1137-43
references.pmid: 18654123
references.citation: Ann Epidemiol. 2008 Apr;18(4):302-9
references.pmid: 18261929
references.citation: Am J Hypertens. 2007 Feb;20(2):119-25
references.pmid: 17261454
references.citation: Lancet. 2002 Dec 14;360(9349):1903-13
references.pmid: 12493255
references.citation: Diabetes Care. 2004 Dec;27(12):2800-5
references.pmid: 15562188
references.citation: J Hum Hypertens. 2006 Aug;20(8):551-3
references.pmid: 16710290
references.citation: J Hypertens. 1999 Feb;17(2):151-83
references.pmid: 10067786
references.citation: Lancet. 2005 Dec 10;366(9502):2005-11
references.pmid: 16338449
references.citation: Blood Press. 1998 May;7(3):176-83
references.pmid: 9758088
references.citation: Arch Intern Med. 2006 Sep 25;166(17):1836-41
references.pmid: 17000939
references.citation: JAMA. 1993 Jun 2;269(21):2779-81
references.pmid: 8492406
references.citation: J Hum Hypertens. 2006 Aug;20(8):625-7
references.pmid: 16543906
references.citation: Circulation. 2008 Jun 3;117(22):2884-92
references.pmid: 18506011
references.citation: Am J Hypertens. 2006 Nov;19(11):1190-6
references.pmid: 17070434
references.citation: Clin Ther. 2007 May;29(5):972-984
references.pmid: 17697916
references.citation: Hypertension. 2004 Jan;43(1):10-7
references.pmid: 14638619
references.citation: Med Care. 2005 Jun;43(6):521-30
references.pmid: 15908846
references.citation: Arch Intern Med. 2007 Dec 10;167(22):2431-6
references.pmid: 18071164
references.citation: BMJ. 2007 Nov 17;335(7628):1030
references.pmid: 17991935
references.citation: J Hypertens. 2004 Oct;22(10):1849-55
references.pmid: 15361751
references.citation: Cochrane Database Syst Rev. 2008 Apr 16;(2):CD000011
references.pmid: 18425859
references.citation: J Clin Epidemiol. 2001 Mar;54(3):217-24
references.pmid: 11223318
references.citation: J Hypertens. 2007 Sep;25(9):1975-7
references.pmid: 17762665
references.citation: Hypertension. 2004 Jan;43(1):1-3
references.pmid: 14676222
references.citation: Int J Clin Pract. 2008 Feb;62(2):338-51
references.pmid: 18199282
references.citation: Am J Med. 2007 Jan;120(1):26-32
references.pmid: 17208076
references.citation: BMC Health Serv Res. 2006 Feb 10;6:8
references.pmid: 16472388
references.citation: J Hypertens. 2006 Jan;24(1):169-75
references.pmid: 16331115