AzTrials
AzTrials

Obstructive Sleep ApneaNCT00843583

A Cross-sectional Study of the Occurrence and Effect of Obstructive Sleep Apnea in Subjects With Resistant Hypertension

An observational study of Obstructive Sleep Apnea and Resistant Hypertension, run by The University of Hong Kong at 1 site in Hong Kong.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
Search all trials

Trial summary

This study aims to investigate the prevalence of obstructive sleep apnea (OSA) in subjects with resistant hypertension and to evaluate the relationship between parameters of OSA severity and blood pressure control Read more about this study

Who is it for?
Ages 18 to 65 years
How many people
96 participants
Where
1 siteHong Kong
Study dates
Feb 2009to Dec 2012
Phase
Observational
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 to 65 years
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Study population: Consecutive sampling of subjects who attend Hypertension clinic , Department of Medicine, Queen Mary Hospital, and who fulfill the inclusion criteria.

Who may be able to join

  • ≧ 3 anti-HT drugs
  • age 18-65
  • mentally fit for signing an informed written consent

Who cannot join

  • moderate renal impairment (glomerular filtration rate <30 mL/min/m2 )
  • endocrine/renal/cardiac causes of secondary HT
  • congestive heart failure and clinically fluid overloaded
  • On drugs that elevate BP e.g. alcohol, NSAID, steroid

Trial locations and contacts

1 site in 1 country.

Hong Kong1 site

  • Department of Medicine, The University of Hong Kong, Queen Mary Hospital

    Hong Kong, 852

Other trials in Hong Kong

About this study

This study aims to investigate the prevalence of obstructive sleep apnea (OSA) in subjects with resistant hypertension and to evaluate the relationship between parameters of OSA severity and blood pressure control

Read the detailed description

Obstructive sleep apnea (OSA) is characterized by intermittent upper airway collapse during sleep, which results in hypoxia, arousals and surge in sympathetic activity. There is robust evidence to support a contributing role of OSA in hypertension (HT). The Sleep Heart Health Study (1), which recruited more than 6000 subjects having polysomnogram at home, found an independent association between OSA and HT. The adjusted odds ratio was 1.37 for subjects with and apnea-hypopnea index >= 30/hour compared to those without apnea. The Wisconsin Sleep Cohort Study , which provided prospective longitudinal follow-up for OSA subjects over 4 years, have shown dose dependency of the severity of OSA and the risk of development of HT. Current available data suggests that in hypertensive patients with severe OSA, there is a BP drop of about 10mmHg with CPAP treatment (2-5). The blood pressure (BP) lowering effect of CPAP treatment in the group with mild asymptomatic OSA is less consolidated.

The relationship between BP and risk of cardiovascular events is continuous, consistent, and independent of other risk factors. A strict blood pressure control is imperative in subjects with diabetes mellitus or renal impairment. Resistant hypertension is defined as blood pressure that remains above goal in spite of concurrent use of 3 antihypertensive agents of different classes. (6) Resistant hypertension is defined in order to identify patients who are at risk of having secondary causes of hypertension, and who may benefit from specific diagnostic and therapeutic applications. Despite the fact that OSA is listed as one of the causes of resistant HT (6), paucity of works has demonstrated the scale of problems of untreated OSA in subjects with resistant HT. (7-9) There is so far one study demonstrating the beneficial effect of CPAP treatment in subjects with resistant HT, though no randomization was implemented and the sample size was limited (n=11). (10) We aim at conducting a cross-sectional study to explore the situation which would guide further clinical trial.

Keywords
prevalence, obstructive sleep apnea, resistant hypertension
Medical subject headings
Sleep Apnea, Obstructive

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

Study groups in NCT00843583
Study groupRoleWhat they receive
resistant hypertension subjectssubjects with resistant hypertension

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. ambulatory blood pressure

    Measured: 24 hour

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted13 Feb 2009 (estimated)
  2. Study startFeb 2009
  3. Primary completionDec 2012
  4. Study completionDec 2012

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Observational
Observational model
Case only
Time perspective
Cross-sectional
Enrolment
96 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT00843583
Sponsor's protocol ID
NCT00843583
Status last verified
May 2017
First submitted
12 Feb 2009
Last updated
3 May 2017
Results posted
No
Data monitoring committee
No

Publications

  • Nieto FJ, Young TB, Lind BK, Shahar E, Samet JM, Redline S, D'Agostino RB, Newman AB, Lebowitz MD, Pickering TG. Association of sleep-disordered breathing, sleep apnea, and hypertension in a large community-based study. Sleep Heart Health Study. JAMA. 2000 Apr 12;283(14):1829-36. doi: 10.1001/jama.283.14.1829.

    PubMed 10770144

  • Pepperell JC, Ramdassingh-Dow S, Crosthwaite N, Mullins R, Jenkinson C, Stradling JR, Davies RJ. Ambulatory blood pressure after therapeutic and subtherapeutic nasal continuous positive airway pressure for obstructive sleep apnoea: a randomised parallel trial. Lancet. 2002 Jan 19;359(9302):204-10. doi: 10.1016/S0140-6736(02)07445-7.

    PubMed 11812555

  • Becker HF, Jerrentrup A, Ploch T, Grote L, Penzel T, Sullivan CE, Peter JH. Effect of nasal continuous positive airway pressure treatment on blood pressure in patients with obstructive sleep apnea. Circulation. 2003 Jan 7;107(1):68-73. doi: 10.1161/01.cir.0000042706.47107.7a.

    PubMed 12515745

  • Mills PJ, Kennedy BP, Loredo JS, Dimsdale JE, Ziegler MG. Effects of nasal continuous positive airway pressure and oxygen supplementation on norepinephrine kinetics and cardiovascular responses in obstructive sleep apnea. J Appl Physiol (1985). 2006 Jan;100(1):343-8. doi: 10.1152/japplphysiol.00494.2005.

    PubMed 16357087

  • Norman D, Loredo JS, Nelesen RA, Ancoli-Israel S, Mills PJ, Ziegler MG, Dimsdale JE. Effects of continuous positive airway pressure versus supplemental oxygen on 24-hour ambulatory blood pressure. Hypertension. 2006 May;47(5):840-5. doi: 10.1161/01.HYP.0000217128.41284.78. Epub 2006 Apr 3.

    PubMed 16585412

  • Calhoun DA, Jones D, Textor S, Goff DC, Murphy TP, Toto RD, White A, Cushman WC, White W, Sica D, Ferdinand K, Giles TD, Falkner B, Carey RM. Resistant hypertension: diagnosis, evaluation, and treatment. A scientific statement from the American Heart Association Professional Education Committee of the Council for High Blood Pressure Research. Hypertension. 2008 Jun;51(6):1403-19. doi: 10.1161/HYPERTENSIONAHA.108.189141. Epub 2008 Apr 7.

    PubMed 18391085

  • Logan AG, Perlikowski SM, Mente A, Tisler A, Tkacova R, Niroumand M, Leung RS, Bradley TD. High prevalence of unrecognized sleep apnoea in drug-resistant hypertension. J Hypertens. 2001 Dec;19(12):2271-7. doi: 10.1097/00004872-200112000-00022.

    PubMed 11725173

  • Grote L, Hedner J, Peter JH. Sleep-related breathing disorder is an independent risk factor for uncontrolled hypertension. J Hypertens. 2000 Jun;18(6):679-85. doi: 10.1097/00004872-200018060-00004.

    PubMed 10872551

  • Lavie P, Hoffstein V. Sleep apnea syndrome: a possible contributing factor to resistant. Sleep. 2001 Sep 15;24(6):721-5. doi: 10.1093/sleep/24.6.721.

    PubMed 11560187

  • Logan AG, Tkacova R, Perlikowski SM, Leung RS, Tisler A, Floras JS, Bradley TD. Refractory hypertension and sleep apnoea: effect of CPAP on blood pressure and baroreflex. Eur Respir J. 2003 Feb;21(2):241-7. doi: 10.1183/09031936.03.00035402.

    PubMed 12608436

  • Lui MMS, Tse HF, Mak JCW, Lam DCL, Chan CWS, Chong PWC, Ip MSM. Untreated Obstructive Sleep Apnea Is Associated With Myocardial Injury Independent of Blood Pressure Control in Hypertension. J Clin Sleep Med. 2018 Nov 15;14(11):1841-1847. doi: 10.5664/jcsm.7476.

    PubMed 30373683

Questions about this trial

What is this clinical trial studying?

An observational study of Obstructive Sleep Apnea and Resistant Hypertension, run by The University of Hong Kong at 1 site in Hong Kong.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 3 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 3 May 2017. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Hong Kong. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

ambulatory blood pressure (time frame: 24 hour). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT00843583, which also lists 11 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 3 May 2017.

AzTrials uses cookies for analytics and advertising. You can accept or reject them; the site works either way. Privacy Policy.

Free account

Log in to keep searching

You’ve used your 3 free searches. AzTrials is free: log in or create a free account to keep searching clinical trials and save the ones you want to follow.

Create a free accountLog in