An observational study in Rheumatoid Arthritis (RA) and Ankylosing Spondylitis (AS), sponsored by Ankara City Hospital Bilkent. Completed at 1 site in Turkey (Türkiye). Open to participants aged 18 Years to 75 Years. Per ClinicalTrials.gov, last updated 2026-11-12.
Sponsored by Ankara City Hospital Bilkent · Observational
Among 127 studies in Arthritis, Rheumatoid with a site in Turkey — 14 open to participants now, 19 under way, 2 of them phase 3. Arthritis, Rheumatoid · Turkey.
Among the 127 studies in Arthritis, Rheumatoid with a site in Turkey, this one is the 43rd largest by enrollment of the 50 observational ones that give a count, is one of 18 that started in 2025, is one of 50 observational ones, and was the 127th registered.
3,334 studies on the registry are indexed under Arthritis, Rheumatoid; 444 are open to participants now.
Browse Arthritis, Rheumatoid studies →14 of the 127 studies in Arthritis, Rheumatoid with a site in Turkey are open now. Recruiting first, the newest first:
Merve Şahin · Sites in Turkey
Ages 18–65 · Healthy volunteers
Medipol University · Sites in Turkey
Ages 20–65
Hasan Kalyoncu University · Sites in Turkey
Ages 19–65
TIPMED Medical Device Manufacturing Ltd. Co. · Sites in Turkey
Ages 18+
Firat University · Sites in Turkey
Ages 18+
A study can be open while its sites in Turkey have not opened yet or have stopped. Only those recruiting at a site in Turkey →
Of the 293 Arthritis, Rheumatoid studies recruiting now, 150 (51%) set no upper age limit and 109 (37%) stop at 75 or younger; 15 take children under 18; 36 take healthy volunteers.
This study: 18 Years to 75 Years · all sexes · no healthy volunteers.
The full table on the hub →This tab as a report to print or save as PDF → With an account.
127 studies; the count open now beside each. This study's row is marked.
A study in two phases is counted once above. Listed by phase, each with its combined phases: Phase 1 1 · Phase 2 9 · Phase 3 20 · Phase 4 7
First in 2001; this study’s year is marked. 18 started in 2025.
By drug class, each counting the studies that test any of its medicines:
This study's enrollment of 53 is below the median of 176 across 1,017 observational studies indexed under Arthritis, Rheumatoid.
Median enrollment 80 across the 77 interventional studies, 100 across the 50 observational. Of the 98 that completed or were terminated, 31 (32%) have results posted.
This tab as a report to print or save as PDF → With an account.
38 of 127 have an industry lead sponsor. The 10 most frequent:
Ankara City Hospital Bilkent is the lead sponsor of 443 studies on the registry; 106 are open to participants now.
Ankara City Hospital Bilkent has 1 study filed under Arthritis, Rheumatoid — fewer than ten, so there is no comparison to draw.
3 of the studies in Arthritis, Rheumatoid with a site in Turkey that are under way reach primary completion within a year, 0 of them phase 3. Phase 3 first, then by date:
| Study | Primary completion |
|---|---|
| NCT07627542Merve ŞahinAn Investigation of the Effect of Smartphone Usage Levels on Cervical Posture, Tongue Pressure, Balance, and Neck Disability in Individuals With Rheumatoid Arthritis and Ankylosing Spondylitis | 2026-11 |
| NCT07666594Tugba Civi KaraaslanMobile App-Based Yoga and Meditation in Rheumatoid Arthritis | 2027-05 |
| NCT07274124Medipol UniversityPain Neuroscience Education and Vagus Nerve Stimulation on Recovery in Individuals With Rheumatoid Arthritis | 2027-05 |
Add all 3 to your calendar (.ics) → With an account.
Among the 127 studies in Arthritis, Rheumatoid with a site in Turkey, from their registry updates:
This tab as a report to print or save as PDF → With an account.
This prospective observational cohort study evaluates whether anti-tumor necrosis factor (anti-TNF) therapy changes the retinal and choroidal microvasculature and retinal structure in patients with rheumatoid arthritis (RA) or ankylosing spondylitis (AS). Patients for whom the rheumatology clinic decided to start anti-TNF therapy as part of routine care are compared with patients who continue treatment without anti-TNF agents. All participants undergo a complete eye examination, optical coherence tomography (OCT) and OCT angiography (OCTA) before treatment and at month 6. The main question is whether retinal vessel density changes differently over time between the two groups.
Background: Chronic systemic inflammation in RA and AS has been associated with endothelial dysfunction and microvascular changes. TNF-alpha is a key mediator of this inflammation, and anti-TNF agents are widely used in both diseases. Prospective data on retinal and choroidal microvasculature with measurements taken before the start of anti-TNF therapy are limited.
Design and participants: Patients with RA or AS followed at the Rheumatology Clinic of Ankara Bilkent City Hospital were referred to the Ophthalmology Clinic between October and December 2025. Treatment decisions were made by the treating rheumatologists, independently of the study. The anti-TNF group consists of anti-TNF-naive patients for whom anti-TNF therapy was planned; their baseline examination was performed before the first dose. The control group consists of patients who were not receiving anti-TNF therapy at baseline and did not start it during the 6-month follow-up.
Assessments: At baseline and month 6, all participants undergo best-corrected visual acuity (logMAR), Goldmann applanation tonometry, slit-lamp biomicroscopy and dilated fundus examination with a +90 D lens. OCT (Heidelberg Spectralis) is used to measure central and sectoral macular thickness, peripapillary retinal nerve fiber layer (RNFL) thickness (global and six sectors) and ganglion cell layer (GCL) thickness. OCTA (RTVue XR Avanti with AngioVue, Optovue) is performed with fovea-centred 6x6 mm scans. Superficial (SCP) and deep capillary plexus (DCP) vessel density are recorded for the whole image, superior and inferior hemifields, and foveal, parafoveal and perifoveal regions with four sectors. Foveal avascular zone (FAZ) area, FAZ perimeter, acircularity index, foveal vessel density and choriocapillaris flow area are also recorded. 3D projection artifact removal is applied. Scans with a quality (Q) score below 6, significant motion or projection artifacts, or segmentation errors are excluded. All examinations are performed by the same, unmasked examiner. ESR and CRP values closest to each visit are obtained from hospital records.
Statistical analysis: Eye-level data are analysed with linear mixed models adjusted for age and sex. The treatment effect is assessed by the group-by-time interaction. The study is reported according to the STROBE guideline.
Adult patients with rheumatoid arthritis or ankylosing spondylitis followed at the Rheumatology Clinic of Ankara Bilkent City Hospital and referred to the Ophthalmology Clinic between October and December 2025.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
History of retinal disease (e.g., diabetic retinopathy, age-related macular degeneration, retinal vein occlusion)
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Anti-TNF-naive patients with RA or AS for whom the treating rheumatologist planned to start anti-TNF therapy as part of routine care. The baseline examination was performed before the first dose.
Drug: Anti-TNF Therapy
Patients with RA or AS who were not receiving anti-TNF therapy at baseline and did not start it during the 6-month follow-up. They continued conventional (non-biologic) treatment.
adalimumab, etanercept, golimumab
Also known as: TNF inhibitor prescribed by the treating rheumatologist according to routine clinical practice; not assigned by the study protocol.
Change in superficial capillary plexus whole-image vessel density
SCP vessel density (%) in fovea-centred 6x6 mm OCTA scans (AngioVue, Optovue). Change from baseline to month 6 is compared between groups (group-by-time interaction).
Time frame: Baseline and month 6
Change in deep capillary plexus whole-image vessel density
DCP vessel density (%) in fovea-centred 6x6 mm OCTA scans. Change from baseline to month 6 is compared between groups.
Time frame: Baseline and month 6
Erythrocyte sedimentation (mm/h) rate
Change in systemic inflammatory marker obtained from hospital records.
Time frame: Baseline and month 6
C-reactive protein (mg/L) value
Change in systemic inflammatory marker obtained from hospital records.
Time frame: Baseline and month 6
Plan to share: No — Individual participant data will not be shared publicly. Aggregate results will be reported in scientific publications.
No publications or documents are linked to this record.
Ran from Nov 2025 to primary completion in Jun 2026, 6 months.
Of 236 non-industry observational studies under Arthritis, Rheumatoid, half reached primary completion within 43 months of starting (the median), counting those still running; a quarter within 19 and three quarters within 122. This study's 6 months is below that.
Counting every sponsor, half of 391 studies reached it within 50 months; a quarter within 25 and three quarters within 113.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is completed, as verified in Nov 2026. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions 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.
Ankara City Hospital Bilkent →