Evidence mapPaperPMID 41557563Full record

Observational studyOphthalmic research2026

Impact of Diabetic Peripheral Neuropathy on Corneal Sensitivity and Ocular Surface.

Pau Cid-Bertomeu, Magí Vilaltella, Laura Capilla, Valentín Huerva

Abstract readObservational Study
In one paragraph

Observational study in Ophthalmic research, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
field-weighted citation impact
1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

4 authors.

Pau Cid-BertomeuDepartment of Ophthalmology, University Hospital Arnau de Vilanova, Lleida, Spain, pauciber@gmail.com.
Magí VilaltellaDepartment of Ophthalmology, University Hospital Arnau de Vilanova, Lleida, Spain.
Laura CapillaDepartment of Ophthalmology, Optometry Section, University Hospital Arnau de Vilanova, Lleida, Spain.
Valentín HuervaDepartment of Ophthalmology, University Hospital Arnau de Vilanova, Lleida, Spain.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

introductionDiabetes mellitus (DM) is frequently associated with microvascular complications, including diabetic peripheral neuropathy (DPN). The cornea, one of the most densely innervated tissues in the body, has been proposed as a surrogate marker for small fiber neuropathy. Patients with DM often present with ocular surface disease (OSD) and corneal sensitivity impairment, but the relationship between DPN, ocular surface alterations, and inflammatory biomarkers remains unclear. This study aimed to evaluate ocular surface parameters between patients with type 2 DM with and without DPN and to explore the associations among corneal sensitivity, ocular surface inflammation (matrix metalloproteinase-9 [MMP-9]), and dry eye-related parameters.

methodsIn this cross-sectional observational study, 158 eyes of 79 patients with type 2 DM were categorized based on the presence or absence of DPN, diagnosed via electromyography. Corneal sensitivity was evaluated using the Brill esthesiometer, and tear MMP-9 levels were assessed with the InflammaDry test. Additional assessments included the Ocular Surface Disease Index (OSDI), tear osmolarity, Schirmer test, noninvasive tear break-up time, and meibography. Corneal impairment was defined as esthesiometry levels 4-6 or pressure thresholds ≥8 mbar in either eye.

resultsPatients with DPN exhibited significantly reduced corneal sensitivity (6.98 ± 2.25 mbar vs. 5.62 ± 2.53 mbar; p = 0.014) and higher OSDI scores (median 26 vs. 10; p < 0.001). MMP-9 positivity was more common in patients with corneal sensory impairment (81.8% vs. 54.3%; p = 0.0215). A significant negative correlation was observed between tear osmolarity and corneal sensitivity (r = -0.182, p = 0.022). Multivariable regression showed that both DPN (β = 1.20) and MMP-9 positivity (β = 1.24) were independently associated with reduced sensitivity.

conclusionsReduced corneal sensitivity was significantly associated with the presence of DPN and with MMP-9 positivity and showed a negative correlation with tear osmolarity. Corneal sensitivity testing combined with tear MMP-9 assessment may provide complementary information on ocular surface changes in diabetic patients, although current variability and limited reproducibility prevent their use as standalone screening tools for neuropathy.

Indexed as

CorneaDiabetes Mellitus, Type 2Diabetic NeuropathiesDry Eye SyndromesAdultAgedCross-Sectional StudiesFemaleHumansMaleMatrix Metalloproteinase 9Middle AgedTearsMatrix Metalloproteinase 9Corneal sensitivityDiabetic peripheral neuropathyDry eyeOcular surface disease

Identifiers

PMID41557563
PMCPMC12923250

What Socratic holds

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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.