Periodontitis Severity in Patients With Diabetic Retinopathy

NCT07137013 | Completed DMC

• 1 other identifier: DR2025/59
• Study Type: observational
• Target: 100
• Locations: 1 country
• Sites: 1

Brief Summary

The aim of this observational study is to investigate the relationship between periodontal disease severity and retinal layer thickness in patients diagnosed with diabetic retinopathy (DR), using optical coherence tomography (OCT) for assessment. The main question this study seeks to answer is: Do measurable changes in retinal layer thickness occur as periodontal disease severity increases in patients with diabetic retinopathy? Participants will include adult individuals with a confirmed clinical diagnosis of DR. Periodontal status will be assessed through standard clinical parameters, including plaque index, probing pocket depth, clinical attachment loss, and bleeding on probing. Retinal layer thickness will be measured using high-resolution OCT and OCT angiography (OCTA) devices. The study aims to analyze potential associations between periodontal disease severity and morphological as well as vascular changes in the retina.

Conditions

Diabetic Retinopathy; Periodontitis

Keywords

Diabetic Retinopathy; Periodontitis; Optical Coherence Tomography; Optical Coherence Tomography Angiography

Outcome Measures

Primary Outcomes (10)

• Optical Coherence Tomography (OCT) Measurement

  A macular thickness map (ETDRS = Early Treatment Diabetic Retinopathy Study) is examined using OCT, with the center at the fovea centralis. According to the ETDRS map, the central 1 mm represents the fovea, the surrounding 3 mm area represents the inner retinal layers, and the outermost 6 mm area represents the outer retinal layers.

  Day 1

• Optical Coherence Tomography Angiography (OCTA) Measurement

  OCTA is a non-invasive technique that allows the evaluation of microvascular changes at the capillary level and imaging of the retinal plexuses layer by layer.

  Day 1

• Retinal Layer Thickness

  Definition: Retinal thickness is the distance between the internal limiting membrane (ILM) and the retinal pigment epithelium (RPE), measured by optical coherence tomography (OCT). ETDRS Mapping: The macular region is divided into nine sectors based on the ETDRS grid: Central subfield: A 1 mm diameter circle centered on the fovea. Inner ring (parafoveal region): 1-3 mm diameter, divided into superior, inferior, nasal, and temporal quadrants. Outer ring (perifoveal region): 3-6 mm diameter, also divided into four quadrants.

  Day 1

• Choroidal Thickness (CSI Reference)

  Definition: The choroid is the vascular layer beneath the RPE. Choroidal thickness is the perpendicular distance from Bruch's membrane to the choroid-sclera interface (CSI). Measurement: Typically obtained with enhanced depth imaging OCT (EDI-OCT), mapped according to the ETDRS grid.

  Day 1

• Ganglion Cell Layer (GCL) Thickness

  Definition: The GCL is composed of the cell bodies of retinal ganglion cells, located between the inner plexiform layer and the retinal nerve fiber layer. Measurement: OCT can quantify GCL alone or GCL + inner plexiform layer (GCL+IPL), usually reported using the ETDRS 9-sector mapping.

  Day 1

• Retinal Nerve Fiber Layer (RNFL) Thickness

  Definition: The RNFL consists of the unmyelinated axons of ganglion cells, located at the innermost surface of the retina. Measurement: Often assessed in the peripapillary region or in the macular area using ETDRS mapping.

  Day 1

• Choroid-Sclera Interface (CSI)

  Definition: The CSI is the outer anatomical boundary of the choroid where it transitions into the sclera. Role in Thickness Measurement: Serves as the lower reference point for choroidal thickness measurements (Bruch's membrane to CSI), which can be mapped according to the ETDRS grid.

  Day 1

• Superficial Retinal Layers

  Definition: The inner portion of the retina, located closer to the vitreous side. Typically associated with the superficial capillary plexus. These layers are among the first affected in diseases such as glaucoma, optic neuropathies, and ischemic retinopathies.

  Day 1

• Deep Retinal Layers

  Definition: The middle and outer portions of the retina, located closer to the photoreceptors. Associated with the deep capillary plexus. Clinical relevance: Important changes are observed here in conditions such as macular edema, diabetic retinopathy, and age-related macular degeneration.

  Day 1

• Foveal Avascular Zone (FAZ)

  Definition: A circular area at the center of the fovea devoid of retinal capillary vessels. Location: In the central fovea, approximately 500-600 micrometers in diameter. Characteristics: Contains the highest density of photoreceptors (especially cones). Avascular nature means nutrition is supplied via diffusion from the choroid. Responsible for the highest visual acuity. Clinical relevance: FAZ size, measurable by OCT angiography (OCTA), is an important biomarker in diabetic retinopathy, retinal vein occlusion, and macular ischemia.

  Day 1

Secondary Outcomes (5)

• Clinical Periodontal Parameters (Plaque Index)

  Day 1

• Clinical Periodontal Parameters (Gingival Index)

  Day 1

• Periodontal Clinical Parametres (Bleeding on Probing Index)

  Day 1

• Periodontal Clinical Parametres (Probing Pocket Depth)

  Day 1

• Periodontal Clinical Parametres (Clinical Attachment Loss)

  Day 1

Study Arms (5)

Control

without systemic disease

DM+ DR-

Diagnosed with Diabetes Mellitus and not diagnosed with Diabetic Retinopathy

NPDR+ DMÖ-

Diagnosed with non-proliferative Diabetic Retinopathy without diabetic macular edema

NPDR+ DMÖ+

Diagnosed with non-proliferative DR with diabetic macular edema

PDR

Diagnosed with proliferative Diabetic Retinopathy

Eligibility Criteria

• Age: 60 Years - 85 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Probability Sample

Study Population

Individuals over the age of 60 who apply to the Department of Ophthalmology at Recep Tayyip Erdoğan University Faculty of Medicine

You may qualify if:

• Men and women aged 60 and over
• Those without systemic disease (control group)
• Patients diagnosed with diabetic retinopathy
• Patients diagnosed with diabetes mellitus (HbA1c\>6)

You may not qualify if:

• Patients with any autoimmune disease, osteoporosis, or cancer
• Patients taking immunosuppressive medications, oral contraceptives, or bisphosphonates
• Pregnancy
• Patients with acute or chronic eye diseases such as vitreoretinal, optic nerve, or choroidal vascular diseases, cataracts, glaucoma, retinal degeneration, uveitis, Behçet's disease, or scleritis
• Patients undergoing refractive or intraocular surgery
• Presence of active infectious disease (acute hepatitis, tuberculosis, AIDS)
• Chronic use of medications affecting periodontal tissues (cyclosporine A, phenytoin)
• Patients taking antioxidant supplements

Sponsors & Collaborators

• Recep Tayyip Erdogan University Training and Research Hospital: lead

Study Sites (1)

Department of Ophthalmology of the Faculty of Medicine of Recep Tayyip Erdogan University

Rize, Rize Province, 53200, Turkey (Türkiye)

Location

MeSH Terms

Conditions

Diabetic Retinopathy; Periodontitis

Condition Hierarchy (Ancestors)

Retinal Diseases; Eye Diseases; Diabetic Angiopathies; Vascular Diseases; Cardiovascular Diseases; Diabetes Complications; Diabetes Mellitus; Endocrine System Diseases; Periodontal Diseases; Mouth Diseases; Stomatognathic Diseases

Study Design

• Study Type: observational
• Observational Model: CASE ONLY
• Time Perspective: CROSS SECTIONAL
• Target Duration: 1 Day
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assoc. Prof. Dr.

Study Record Dates

• First Submitted: August 11, 2025
• First Posted: August 22, 2025
• Study Start: February 24, 2025
• Primary Completion: May 12, 2025
• Study Completion: June 23, 2025
• Last Updated: August 22, 2025

Record last verified: 2025-08

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)