Official Title: “Prognostic Value of Ambulatory Blood Pressure Monitoring in the Prediction of Cardiovascular Events and Effects of Chronotherapy in Relation to Risk (the MAPEC Study).”

The MAPEC study was designed to investigate whether normalizing the circadian blood pressure profile towards a more dipper pattern (increasing the diurnal/nocturnal ratio of blood pressure) by the use of Chronotherapy (that is, taking into account the time of day of administration of antihypertensive medications) reduces cardiovascular risk.

Study Type: Interventional

Study Design: Treatment, Randomized, Open Label, Active Control, Parallel Assignment, Safety/Efficacy Study

Study Primary Completion Date: April 2009

Target organ damage is more closely associated with ambulatory (ABPM) than with clinic blood pressure (BP). In particular, the reduction of the normal 10 to 20% sleep-time BP decline (non-dipper pattern) is associated with elevated risk of end-organ injury, particularly to the heart, brain and kidney.

These results suggest that cardiovascular risk could be influenced not by BP elevation alone, but also by the magnitude of the circadian BP variability.

Moreover, at least two independent prospective studies have suggested that nighttime BP is a better predictor of risk than daytime BP. Common to all previous trials is that prognostic significance of ABPM has relied on a single baseline profile from each participant, without accounting for possible changes in the BP pattern, mainly associated to antihypertensive therapy and aging during follow-up. The MAPEC study investigates, first, the comparative prognostic value of several BP parameters (including, among many others, BP variability, the diurnal/nocturnal ratio, diurnal and nocturnal means, slope of morning rise, etc) in the prediction of cardiovascular morbidity and mortality; and, second, whether potential changes in the circadian BP pattern after Chronotherapy with antihypertensive drugs are associated to changes in cardiovascular risk.

Intervention(s) in this Clinical Trial

• Device: Ambulatory blood pressure monitoring
  • Sampling at 20-min intervals from 07:00 to 23:00 hours and at 30-min intervals at night for 48 consecutive hours
• Procedure: Chronotherapy, timing of antihypertensive medication
  • Comparison of effects of awakening versus bedtime dosing
• Drug: ACEI (including spirapril, enalapril, quinapril, lisinopril)
  • Treatment at awakening versus bedtime
• Drug: ARB (including valsartan, telmisartan, olmesartan)
  • Treatment at awakening versus bedtime
• Drug: beta blockers (including nebivolol, atenolol, carvedilol)
  • Treatment at awakening versus bedtime
• Drug: diuretics (torasemide, indapamide, HTCZ) and doxazosin
  • Treatment at awakening versus bedtime
• Procedure: Combination therapy in essential hypertension
  • Treatment at awakening versus bedtime

Arms, Groups and Cohorts in this Clinical Trial

• Active Comparator: 1
  • Treatment on awakening
• Active Comparator: 2
  • Treatment at bedtime

Primary Measures

• Prognostic value of ABPM, impact of changes in ambulatory BP and impact of circadian time of antihypertensive treatment in cardiovascular, cerebrovascular and renal risk assessment.
  • Time Frame: Five years
    Safety Issue?: Yes

Secondary Measures

• Influence of circadian time of antihypertensive treatment in BP control and the remodeling of the circadian BP pattern of hypertensive patients.
  • Time Frame: Five years
    Safety Issue?: Yes
• Prevalence of an altered BP profile as a function of the circadian time of treatment.
  • Time Frame: Five years
    Safety Issue?: Yes

Inclusion Criteria:

• Essential hypertension

Exclusion Criteria:

• AIDS
• shift workers
• secondary hypertension
• intolerant to ABPM

Gender Eligibility for this Clinical Trial: Both

Minimum Age for this Clinical Trial: 18 Years

Maximum Age for this Clinical Trial: N/A

Are Healthy Volunteers Accepted for this Clinical Trial?: Accepts Healthy Volunteers

Lead Sponsor: University of Vigo

Overall Clinical Trial Officials and Contacts

Ramon C Hermida, PhD Principal Investigator University of Vigo  

Information obtained from ClinicalTrials.gov on July 02, 2009

Link to the current ClinicalTrials.gov record. http://clinicaltrials.gov/show/NCT00295542

Study ID Number: PGIDIT03-PXIB-32201PR

ClinicalTrials.gov Identifier: NCT00295542

Health Authority: Spain: Ministry of Health