CClinicalTrials.gg
Sign In
Active, not recruitingNCT05703763ATOM-GCAUpdated Aug 7, 2025

The Applanation Tonometry in GCA Pilot

An observational study in Giant Cell Arteritis, sponsored by Centre Integre Universitaire de Sante et Services Sociaux du Nord de l'ile de Montreal. Active, not recruiting at 1 site in Canada. Open to participants aged 50 Years to 99 Years. Per ClinicalTrials.gov, last updated 2025-08-07.

Sponsored by Centre Integre Universitaire de Sante et Services Sociaux du Nord de l'ile de Montreal · Observational

From the registry’s dates

  • Primary completion was expected by Jun 2026, 4 months ago, but the record still lists the study as active, not recruiting.
Study type
Observational
Model
Cohort
Time perspective
Prospective
Enrollment
146
Ages
50 Years to 99 Years
Sex
All
01

Study summary

The Applanation Tonometry in Giant Cell Arteritis (ATOM-GCA) study will answer the following questions:

  1. How does PWV, measured by applanation tonometry of temporal arteries, differ between patients with and without a final diagnosis of GCA (based on pre-defined criteria 6 months after inclusion)?

  2. What is the diagnostic accuracy and positivity cutoff of the PWV, measured by applanation tonometry, in detecting:

    1. A clinical diagnosis of GCA (based on pre-defined criteria 6 months after inclusion)?
    2. Inflammation of temporal arteries on high-resolution ultrasound?
  3. What is the acceptability and adherence of repeat applanation tonometry during the follow-up period in patients with GCA?
Read the detailed description

ATOM-GCA is a single-center, cross-sectional vanguard study.

02

Conditions studied

  • Giant Cell Arteritis

Keywords

  • diagnosis
03

In context

Giant Cell Arteritis

170 studies on the registry are indexed under Giant Cell Arteritis; 48 are open to participants now.

This study's planned enrollment of 146 is above the median of 122 across 85 observational studies indexed under Giant Cell Arteritis.

Browse Giant Cell Arteritis studies →

Lead sponsor

Centre Integre Universitaire de Sante et Services Sociaux du Nord de l'ile de Montreal is the lead sponsor of 31 studies on the registry; 15 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
50 Years to 99 Years
Sexes eligible
All
Accepts healthy volunteers
No
Sampling method
Non-probability sample

Study population

Consecutive patients referred for suspected new-onset GCA

Inclusion criteria

To be included in ATOM-GCA, participants must meet all the following criteria:

  1. Age > 50 years.
  2. Referral for suspected, new-onset GCA.
  3. Ability to understand and willingness to sign an informed consent form.
  4. Willingness to comply with study visits and procedures.

Exclusion criteria

Exclusion criteria:

An individual who meets any of these criteria will be excluded from ATOM-GCA:

  1. Referral for a suspected GCA relapse.

  2. Current use of systemic glucocorticoids, with the following duration at the baseline visit:

    1. ≥ 14 consecutive days of oral glucocorticoids in the previous 30 days, or
    2. ≥ 7 consecutive days of oral glucocorticoids if intravenous glucocorticoids were administered in the previous 30 days.
  3. Current use of any conventional or biologic immunosuppressive therapy.
  4. Temporal artery biopsy prior to the study visit.
05

Study design

Observational model
Cohort
Time perspective
Prospective
Enrollment
146 participants (estimated)
Patient registry
No

Groups and cohorts

  • GCA group

    Definite confirmation of GCA will occur 6 months after study inclusion, following the phone follow-up, and will require all the following features: 1) initial symptoms and clinical evolution consistent with GCA; 2) at least one positive test for cranial GCA (ultrasound of temporal arteries, temporal artery biopsy, cranial MRI, cranial PET); and 3) satisfies the 2022 ACR-EULAR classification criteria for GCA.

    Diagnostic Test: Applanation tonometry · Diagnostic Test: Standardized GCA assessment · Diagnostic Test: Repeat applanation tonometry (optional)

  • Non-GCA group

    Participants who do not meet the criteria (above) for GCA at month 6.

    Diagnostic Test: Applanation tonometry · Diagnostic Test: Standardized GCA assessment

Interventions

  • Diagnostic testApplanation tonometry

    Applanation tonometry will be used to measure arterial stiffness in these segments, bilaterally: * Superficial temporal artery to frontal temporal artery * Common carotid artery to superficial temporal artery

  • Diagnostic testStandardized GCA assessment

    Clinical assessment, blood test review, high-resolution temporal artery ultrasound using a 24mHz probe.

  • Diagnostic testRepeat applanation tonometry (optional)

    Repeat index test at month 6 and at disease relapse.

06

What researchers measure

Primary outcomes

  1. PWV in patients with and without GCA

    The primary outcome of ATOM-GCA is to compare the mean PWV in patients with GCA to the mean PWV in individuals without GCA. Final confirmation of GCA will be determined 6 months after study inclusion. This analysis will establish whether the PWV differs in GCA. Additionally, we will explore the optimal PWV cutoff and evaluate its diagnostic performance to confirm a final diagnosis of GCA at 6 months.

    Time frame: Baseline

Secondary outcomes

  1. Diagnostic performance of the PWV

    The secondary outcome is to assess the diagnostic performance of the PWV to predict the presence of GCA-induced inflammation on high-resolution ultrasound. This analysis will identify the optimal PWV cutoff to potentially replace temporal artery ultrasound in GCA diagnosis.

    Time frame: Baseline

Other outcomes

  1. Proportion of participants who accept repeat applanation tonometry

    In patients with GCA, we will evaluate the acceptability of applanation tonometry by measuring the proportion of participants who, at the baseline visit, consent to undergo repeated applanation tonometry during the follow-up period.

    Time frame: Baseline

  2. Proportion of participants who complete repeated applanation tonometry

    The adherence of repeat applanation tonometry (proportion of patient who successfully complete applanation tonometry at month 6 and at relapse) will be assessed in those who consented to have repeat applanation tonometry.

    Time frame: Up to 2 years

07

Study locations

1 site
  • Vasculitis Clinic, Hopital du Sacre-Coeur de Montreal
    Montreal, Quebec H4J1C5, Canada
08

References and documents

Publications

  • Zarka F, Rheaume M, Belhocine M, Goulet M, Febrer G, Mansour AM, Troyanov Y, Starnino T, Meunier RS, Chagnon I, Routhier N, Benard V, Ducharme-Benard S, Ross C, Makhzoum JP. Colour Doppler ultrasound and the giant cell arteritis probability score for the diagnosis of giant cell arteritis: a Canadian single-centre experience. Rheumatol Adv Pract. 2021 Nov 10;5(3):rkab083. doi: 10.1093/rap/rkab083. eCollection 2021. PubMed 34859177 ↗
  • Baalbaki H, Jalaledin D, Lachance C, Febrer G, Rheaume M, Makhzoum JP. Characterization of visual manifestations and identification of risk factors for permanent vision loss in patients with giant cell arteritis. Clin Rheumatol. 2021 Aug;40(8):3207-3217. doi: 10.1007/s10067-021-05643-5. Epub 2021 Feb 12. PubMed 33580374 ↗

Individual participant data

Plan to share: Undecided

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Aug 7, 2025, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT05703763
Lead sponsor
Centre Integre Universitaire de Sante et Services Sociaux du Nord de l'ile de Montreal
Responsible party
Jean-Paul Makhzoum (Director - Vasculitis Research Program, Principal Investigator, Centre Integre Universitaire de Sante et Services Sociaux du Nord de l'ile de Montreal) — Principal investigator
First posted
Jan 30, 2023
Start date
Jul 30, 2025
Primary completion
Jun 2026 (estimated)
Completion
Jul 2027 (estimated)
Last update
Aug 7, 2025

Study contacts

Jean-Paul Makhzoum
study chair · CISSS du Nord-de-l'ile de Montreal

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is active, not recruiting, as verified in Jul 2025. You cannot join it, but the record below documents what was studied.

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Other studies in this condition

Giant Cell Arteritis→

Other studies from this sponsor

Centre Integre Universitaire de Sante et Services Sociaux du Nord de l'ile de Montreal

Start the discussion