title: Home blood pressure monitoring, secure electronic messaging and medication intensification for improving hypertension control: a mediation analysis.
abstract: OBJECTIVE
  We evaluated the role of home monitoring, communication with pharmacists, medication intensification, medication adherence and lifestyle factors in contributing to the effectiveness of an intervention to improve blood pressure control in patients with uncontrolled essential hypertension.
  
  
  METHODS
  We performed a mediation analysis of a published randomized trial based on the Chronic Care Model delivered over a secure patient website from June 2005 to December 2007. Study arms analyzed included usual care with a home blood pressure monitor and usual care with home blood pressure monitor and web-based pharmacist care. Mediator measures included secure messaging and telephone encounters; home blood pressure monitoring; medications intensification and adherence and lifestyle factors. Overall fidelity to the Chronic Care Model was assessed with the Patient Assessment of Chronic Care (PACIC) instrument. The primary outcome was percent of participants with blood pressure (BP) <140/90 mm Hg.
  
  
  RESULTS
  At 12 months follow-up, patients in the web-based pharmacist care group were more likely to have BP <140/90 mm Hg (55%) compared to patients in the group with home blood pressure monitors only (37%) (p = 0.001). Home blood pressure monitoring accounted for 30.3% of the intervention effect, secure electronic messaging accounted for 96%, and medication intensification for 29.3%. Medication adherence and self-report of fruit and vegetable intake and weight change were not different between the two study groups. The PACIC score accounted for 22.0 % of the main intervention effect.
  
  
  CONCLUSIONS
  The effect of web-based pharmacist care on improved blood pressure control was explained in part through a combination of home blood pressure monitoring, secure messaging, and antihypertensive medication intensification.
authors.affiliation: Group Health Research Institute 1730 Minor Ave , Suite 1600, Seattle, WA 98101-1448.
authors.forename: J D
authors.initials: JD
authors.lastname: Ralston
authors.affiliation: Group Health Research Institute 1730 Minor Ave , Suite 1600, Seattle, WA 98101-1448.
authors.forename: A J
authors.initials: AJ
authors.lastname: Cook
authors.affiliation: Group Health Research Institute 1730 Minor Ave , Suite 1600, Seattle, WA 98101-1448.
authors.forename: M L
authors.initials: ML
authors.lastname: Anderson
authors.affiliation: Group Health Research Institute 1730 Minor Ave , Suite 1600, Seattle, WA 98101-1448.
authors.forename: S L
authors.initials: SL
authors.lastname: Catz
authors.affiliation: Group Health Research Institute 1730 Minor Ave , Suite 1600, Seattle, WA 98101-1448.
authors.forename: P A
authors.initials: PA
authors.lastname: Fishman
authors.affiliation: Group Health Research Institute 1730 Minor Ave , Suite 1600, Seattle, WA 98101-1448.
authors.forename: J
authors.initials: J
authors.lastname: Carlson
authors.affiliation: Group Health Research Institute 1730 Minor Ave , Suite 1600, Seattle, WA 98101-1448.
authors.forename: R
authors.initials: R
authors.lastname: Johnson
authors.affiliation: Group Health Research Institute 1730 Minor Ave , Suite 1600, Seattle, WA 98101-1448.
authors.forename: B B
authors.initials: BB
authors.lastname: Green
mesh_terms: D000959:Antihypertensive Agents / Q000627:therapeutic use*; D018660:Blood Pressure Monitoring, Ambulatory; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D017008:Negotiating; D016032:Randomized Controlled Trials as Topic; D017216:Telemedicine / Q000379:methods*
chemical_list: D000959:Antihypertensive Agents
keywords: Personal health records; home care and e-health; internet portal; patient self-care; patient-provider communication; remote monitoring; telemedicine and telehealth
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