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Autonomic Dysfunction in Resistant Hypertension (RH)

This study has been completed.
Information provided by (Responsible Party):
Valéria Nasser Figueiredo, University of Campinas, Brazil Identifier:
First received: April 5, 2013
Last updated: April 12, 2013
Last verified: February 2012
The contribution of this study is the unedited evaluation of the circadian autonomic profiles of resistant hypertension with and without white-coat response.

Hypertension, Resistant to Conventional Therapy

Study Type: Observational [Patient Registry]
Study Design: Observational Model: Cohort
Target Follow-Up Duration: 10 Months
Official Title: Circadian Autonomic Disturbances in Resistant Hypertension With and Without White-coat Phenomenon

Further study details as provided by Valéria Nasser Figueiredo, University of Campinas, Brazil:

Primary Outcome Measures:
  • evaluation of the autonomic function in resistant hypertensive patients [ Time Frame: 10 months ]

    The autonomic nervous system can be assessed by the heart rate variability. Variations in heart rate variability are normally observed in association with diurnal rhythms and blood pressure changes. The heart rate variability parameters are different in many studies, although the consensus is that lower values of the indices of vagal as well as high indices of sympathetic functions are associated prospectively with death and disability.

    In humans, the disturbances of the circadian rhythms of heart rate variability and blood pressure have been intensively studied, mainly due to the increased cardiovascular death reported during the morning hours

Enrollment: 44
Study Start Date: September 2011
Study Completion Date: December 2012
Primary Completion Date: November 2012 (Final data collection date for primary outcome measure)
Resistant Hypertension
The current definition of resistant hypertension (RH) includes both patients whose blood pressure (BP) is uncontrolled on three or more medications and those whose BP is controlled when using four or more antihypertensive medications

Detailed Description:

All patients were submitted to office blood pressure measurement, Ambulatory blood pressure monitoring and 24-hour Holter monitoring.

Baseline blood samples for the measurement of glycemia (mg/dL), total cholesterol (mg/dL), LDL cholesterol (mg/dL), triglycerides (mg/dL), creatinine (mg/dL), serum uric acid, serum sodium, serum potassium, plasma aldosterone concentration (PAC) and plasma renin activity (PRA) were collected at 08:00 after overnight fasting.


Ages Eligible for Study:   30 Years to 60 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Probability Sample
Study Population
Forty-four resistant hypertension subjects, regularly followed up at the cardiovascular clinical pharmacology out-patients' clinic, and who complied with pharmacological prescription for hypertension, were recruited to participate in this transversal and observational study.

Inclusion Criteria:

  • resistant hypertensive patients

Exclusion Criteria:

  • White-coat hypertension
  • obstructive sleep apnea
  Contacts and Locations
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Please refer to this study by its identifier: NCT01833429

Cardiovascular Pharmacology Laboratory
Campinas, Sao Paulo, Brazil, 13083-888
Sponsors and Collaborators
University of Campinas, Brazil
  More Information

Responsible Party: Valéria Nasser Figueiredo, PhD, University of Campinas, Brazil Identifier: NCT01833429     History of Changes
Other Study ID Numbers: 907/2011
Study First Received: April 5, 2013
Last Updated: April 12, 2013

Keywords provided by Valéria Nasser Figueiredo, University of Campinas, Brazil:
Resistant hypertension
White-coat phenomenon
Heart rate variability
autonomic activity

Additional relevant MeSH terms:
Coronary Vasospasm
Vascular Diseases
Cardiovascular Diseases
Coronary Disease
Myocardial Ischemia
Heart Diseases processed this record on August 18, 2017