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Trial registered on ANZCTR


Registration number
ACTRN12618000757213
Ethics application status
Approved
Date submitted
23/04/2018
Date registered
4/05/2018
Date last updated
10/08/2018
Type of registration
Retrospectively registered

Titles & IDs
Public title
Daily variation in sleep apnea status and atrial fibrillation.
Scientific title
Night-to-night variability in severity of sleep apnea and daily dynamic atrial fibrillation risk.
Secondary ID [1] 294693 0
None.
Universal Trial Number (UTN)
U1111-1212-7527
Trial acronym
VARIOSA-AF
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Sleep Apnea 307553 0
Atrial Fibrillation 307554 0
Condition category
Condition code
Cardiovascular 306632 306632 0 0
Diseases of the vasculature and circulation including the lymphatic system
Respiratory 306773 306773 0 0
Sleep apnoea

Intervention/exposure
Study type
Observational
Patient registry
False
Target follow-up duration
Target follow-up type
Description of intervention(s) / exposure
Observational Study:
Daily data on atrial fibrillation burden and average respiratory disturbance index (RDI, sleep apnea status)) were extracted from a sample of Reply 200 or Kora 100 DR pacemakers in 72 patients with a mean follow-up per patient of 21±7 weeks. Nightly RDI within each patient was grouped into quartiles, with the highest quartile representing the 25% of nights with most severe SDB for that particular patient. A daily cumulative AF-burden of >5 mins, >1 hr and >12 hrs per day were the outcome variables.
Intervention code [1] 300986 0
Early Detection / Screening
Comparator / control treatment
No control group.
Control group
Uncontrolled

Outcomes
Primary outcome [1] 305626 0
Daily cumulative atrial fibrillation burden (> 5 minutes) as assessed by pacemaker data extraction.
Timepoint [1] 305626 0
Assessed daily for an average follow up of 21±7 weeks.
Secondary outcome [1] 345968 0
Daily SDB-severity assessed by pacemaker data extraction.
Timepoint [1] 345968 0
Assessed daily for an average follow up of 21±7 weeks.

Eligibility
Key inclusion criteria
Implanted dual-chamber pacemakers Reply 200 or Kora 100 DR (LivaNova, France) with implemented SDB monitoring (SAM) measuring a respiratory disturbance index (RDI)
Minimum age
18 Years
Maximum age
No limit
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
- <1 month of follow-up since implant
- SDB monitoring (SAM) turned off
- >10% invalid RDI
- unreliable mode switch estimates due to atrial under sensing
- persistent AF throughout the recording

Study design
Purpose
Natural history
Duration
Cross-sectional
Selection
Defined population
Timing
Retrospective
Statistical methods / analysis
Data are described by mean ± standard deviation when normally distributed and median [IQR] if data follow a skewed distribution. Categorical data are expressed as percentage with numerator and denominator in brackets. A binary logistic generalized estimating equation (GEE) was used to develop a prediction model for the dichotomous AF outcome (>5 mins OR >1 hr OR >12 hrs of cumulative mode switch per day) using the within-patient standardized (via quartiles) sleep severity data.
All data will be analyzed using SPSS (Version 24) and significance was set at p<0.05.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
SA
Recruitment hospital [1] 10777 0
The Royal Adelaide Hospital - Adelaide
Recruitment postcode(s) [1] 22515 0
5000 - Adelaide

Funding & Sponsors
Funding source category [1] 299300 0
Other Collaborative groups
Name [1] 299300 0
Center for Heart Rhythm Disorders.
Address [1] 299300 0
Centre for Heart Rhythm Disorders,
Department of Cardiology, Royal Adelaide Hospital,
North Terrace
Adelaide,
South Australia 5000
AUSTRALIA
Country [1] 299300 0
Australia
Primary sponsor type
Other Collaborative groups
Name
Center for Heart Rhythm Disorders.
Address
Centre for Heart Rhythm Disorders,
Department of Cardiology, Royal Adelaide Hospital,
North Terrace
Adelaide,
South Australia 5000
AUSTRALIA
Country
Australia
Secondary sponsor category [1] 298567 0
None
Name [1] 298567 0
Address [1] 298567 0
Country [1] 298567 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 300211 0
Royal Adelaide Hospital Human Research Ethics Committee
Ethics committee address [1] 300211 0
Central Adelaide Local Health Network
Royal Adelaide Hospital Human Research Ethics Committee
Level 4, Women’s Health Centre
Royal Adelaide Hospital
North Terrace
Adelaide, South Australia, 5000
Ethics committee country [1] 300211 0
Australia
Date submitted for ethics approval [1] 300211 0
20/02/2017
Approval date [1] 300211 0
26/04/2017
Ethics approval number [1] 300211 0
HREC/17/RAH/53

Summary
Brief summary
The diagnosis of sleep-disordered breathing (SDB) is associated with increased incidence and prevalence of atrial fibrillation (AF). However, nightly SDB-severity rather than the categorical diagnosis of SDB may directly influence AF-risk during the respective day thereby creating a dynamic substrate for AF. While chronic structural alterations induced by SDB have been already described in AF patients with SDB, the role of night-to-night variability in SDB severity is unclear and clinical evidence for a dynamic AF substrate in patients related to nightly SDB severity is lacking. By simultaneous long-term night-by-night SDB and AF monitoring, we examine the dynamic intra-individual relationship between daily SDB-severity and risk of incident AF during the respective day.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 82926 0
Dr Dominik Linz
Address 82926 0
Centre for Heart Rhythm Disorders,
Department of Cardiology, Royal Adelaide Hospital,
North Terrace
Adelaide,
South Australia 5000
AUSTRALIA
Country 82926 0
Australia
Phone 82926 0
+61882222723
Fax 82926 0
+61882222722
Email 82926 0
Dominik.Linz@adelaide.edu.au
Contact person for public queries
Name 82927 0
Dr Dominik Linz
Address 82927 0
Centre for Heart Rhythm Disorders,
Department of Cardiology, Royal Adelaide Hospital,
North Terrace
Adelaide,
South Australia 5000
AUSTRALIA
Country 82927 0
Australia
Phone 82927 0
+61882222723
Fax 82927 0
+61882222722
Email 82927 0
Dominik.Linz@adelaide.edu.au
Contact person for scientific queries
Name 82928 0
Dr Dominik Linz
Address 82928 0
Centre for Heart Rhythm Disorders,
Department of Cardiology, Royal Adelaide Hospital,
North Terrace
Adelaide,
South Australia 5000
AUSTRALIA
Country 82928 0
Australia
Phone 82928 0
+61882222723
Fax 82928 0
+61882222722
Email 82928 0
Dominik.Linz@adelaide.edu.au

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary