Normal Tension GlaucomaNCT03387306
Serum Bilirubin Levels in Normal-tension Glaucoma
An observational study of Normal Tension Glaucoma and Bilirubin; Defect, Excretion, run by Trakya University at 1 site in Turkey (Türkiye).
Trial summary
Purpose: To analyze the relationship between normal-tension glaucoma (NTG) and serum bilirubin levels. Materials and Methods: This research included 38 patients with NTG and 38 healthy controls with similar age and sex distribution, for a total of 76 subjects. Read more about this study
- Who is it for?
- Ages 18 to 80 years
- Conditions the study is for
- Normal Tension Glaucoma, Bilirubin; Defect, Excretion
- How many people
- 76 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- Jan 2010to Apr 2017
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 80 years
- All sexes
- Adult, Older adult
Study population: NTG was diagnosed based on a clinical examination showing a normal IOP (corrected for corneal thickness), thinning of the peripapillary retinal nerve fibre layer, optic nerve damage, and characteristic glaucomatous visual field defects. The exclusion criteria included other forms of glaucoma such as primary open-angle glaucoma, primary closed-angle glaucoma, pigmentary glaucoma and exfoliative glaucoma. Patients who had active systemic diseases such as those affecting the liver, biliary system, pancreas and kidney and infectious diseases or malignant tumours that could influence the serum bilirubin concentrations were also excluded.
Who may be able to join
- Healthy volunteers
Who cannot join
- Patients who had active systemic diseases such as those affecting the liver, biliary system, pancreas and kidney and infectious diseases or malignant tumours that could influence the serum bilirubin concentrations were excluded.
Trial locations and contacts
1 site in 1 country.
Turkey (Türkiye)1 site
Sadık Altan Ozal
Edirne, In the USA Or Canada, Please Select..., 22030
About this study
Official title: Reduced Serum Bilirubin Levels in Patients With Normal-tension Glaucoma
Purpose: To analyze the relationship between normal-tension glaucoma (NTG) and serum bilirubin levels.
Materials and Methods: This research included 38 patients with NTG and 38 healthy controls with similar age and sex distribution, for a total of 76 subjects. Serum samples were taken from all of the subjects, direct serum bilirubin, indirect serum bilirubin and the total serum bilirubin were measured.
Read the detailed description
This is a retrospective study of cases with recently or previously diagnosed NTG who were admitted to our clinic between 2010 and 2017. This study included 38 patients with NTG and 38 healthy controls with similar age and sex distribution, for a total of 76 subjects. Written informed consent was obtained from all of the participants. The study was approved by the institutional review board of the hospital and adhered to the tenets of the Declaration of Helsinki.
A complete ophthalmic examination including best-corrected visual acuity, slit-lamp biomicroscopy, Goldmann applanation tonometry (AT 900, Haag-Streit Diagnostics, Koeniz, CH), corneal thickness evaluation (Pachymeter SP-3000, Tomey Corporation, Nagoya, JP), gonioscopy and ophthalmoscopy was performed in all NTG cases. Additionally, optical coherence tomography (OCT RS-3000 Lite, NIDEK Corporation, Tokyo, JP) measurement of the peripapillary retinal nerve fibre layer thickness, and Humprey visual field testing (Carl-Zeiss Meditec, Dublin, CA) were also performed.
NTG was diagnosed based on a clinical examination showing a normal IOP (corrected for corneal thickness), thinning of the peripapillary retinal nerve fibre layer, optic nerve damage, and characteristic glaucomatous visual field defects. The exclusion criteria included other forms of glaucoma such as primary open-angle glaucoma, primary closed-angle glaucoma, pigmentary glaucoma and exfoliative glaucoma. Patients who had active systemic diseases such as those affecting the liver, biliary system, pancreas and kidney and infectious diseases or malignant tumours that could influence the serum bilirubin concentrations were also excluded.
Fasting blood samples were taken from each participant to measure direct bilirubin, indirect bilirubin, and the total serum bilirubin concentrations. The direct bilirubin and total bilirubin concentrations were measured with an Architect C16000 Clinical Chemistry Analyzer (Abbott Laboratories, Abbott Park, IL, USA), using its original kits, and the indirect bilirubin concentrations were calculated by the following formula: indirect bilirubin = total bilirubin - direct bilirubin.
All the data were compiled into a computer file, and Statistical Package for Social Sciences for Windows 22.0 was used to perform the statistical analysis. Student's t test or the Mann-Whitney U test were used to compare the mean values between the two groups, after the evaluation of the data for a normal distribution using the Kolmogorov-Smirnov test. A p value less than 0.05 was considered statistically significant.
- Keywords
- serum bilirubin, normal-tension glaucoma, oxidative stress
- Medical subject headings
- Low Tension Glaucoma
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| Patient group | This grup included 38 patients with NTG. | |
| Control group | This group included 38 healthy controls. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Serum Bilirubin Levels
Serum indirect, direct and total bilirubin levels
Measured: January 2017-March 2017
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted2 Jan 2018
- Study startJan 2010
- Primary completionMar 2017
- Study completionApr 2017
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (19)Papers the sponsor has linked to this study.
- Other trials for Normal Tension GlaucomaStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Case-control
- Time perspective
- Retrospective
- Enrolment
- 76 participants (actual)
Sponsor and investigators
- Lead sponsor
- Trakya University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Sadık Altan Ozal, Trakya University
- Investigators
- Sadık Altan Ozal, Principal investigator, Trakya University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03387306
- Sponsor's protocol ID
- 14783786
- Status last verified
- Dec 2017
- First submitted
- 21 Dec 2017
- Last updated
- 2 Jan 2018
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Tham YC, Li X, Wong TY, Quigley HA, Aung T, Cheng CY. Global prevalence of glaucoma and projections of glaucoma burden through 2040: a systematic review and meta-analysis. Ophthalmology. 2014 Nov;121(11):2081-90. doi: 10.1016/j.ophtha.2014.05.013. Epub 2014 Jun 26.
PubMed 24974815Flammer J, Mozaffarieh M. What is the present pathogenetic concept of glaucomatous optic neuropathy? Surv Ophthalmol. 2007 Nov;52 Suppl 2:S162-73. doi: 10.1016/j.survophthal.2007.08.012.
PubMed 17998042Mallick J, Devi L, Malik PK, Mallick J. Update on Normal Tension Glaucoma. J Ophthalmic Vis Res. 2016 Apr-Jun;11(2):204-8. doi: 10.4103/2008-322X.183914.
PubMed 27413503Cho HK, Kee C. Population-based glaucoma prevalence studies in Asians. Surv Ophthalmol. 2014 Jul-Aug;59(4):434-47. doi: 10.1016/j.survophthal.2013.09.003. Epub 2014 May 13.
PubMed 24837853Iwase A, Suzuki Y, Araie M, Yamamoto T, Abe H, Shirato S, Kuwayama Y, Mishima HK, Shimizu H, Tomita G, Inoue Y, Kitazawa Y; Tajimi Study Group, Japan Glaucoma Society. The prevalence of primary open-angle glaucoma in Japanese: the Tajimi Study. Ophthalmology. 2004 Sep;111(9):1641-8. doi: 10.1016/j.ophtha.2004.03.029.
PubMed 15350316Cursiefen C, Wisse M, Cursiefen S, Junemann A, Martus P, Korth M. Migraine and tension headache in high-pressure and normal-pressure glaucoma. Am J Ophthalmol. 2000 Jan;129(1):102-4. doi: 10.1016/s0002-9394(99)00289-5.
PubMed 10653426Henry E, Newby DE, Webb DJ, O'Brien C. Peripheral endothelial dysfunction in normal pressure glaucoma. Invest Ophthalmol Vis Sci. 1999 Jul;40(8):1710-4.
PubMed 10393040Himori N, Kunikata H, Shiga Y, Omodaka K, Maruyama K, Takahashi H, Nakazawa T. The association between systemic oxidative stress and ocular blood flow in patients with normal-tension glaucoma. Graefes Arch Clin Exp Ophthalmol. 2016 Feb;254(2):333-41. doi: 10.1007/s00417-015-3203-z. Epub 2015 Oct 30.
PubMed 26514963Yuki K, Murat D, Kimura I, Ohtake Y, Tsubota K. Reduced-serum vitamin C and increased uric acid levels in normal-tension glaucoma. Graefes Arch Clin Exp Ophthalmol. 2010 Feb;248(2):243-8. doi: 10.1007/s00417-009-1183-6. Epub 2009 Sep 8.
PubMed 19763599Harada T, Harada C, Nakamura K, Quah HM, Okumura A, Namekata K, Saeki T, Aihara M, Yoshida H, Mitani A, Tanaka K. The potential role of glutamate transporters in the pathogenesis of normal tension glaucoma. J Clin Invest. 2007 Jul;117(7):1763-70. doi: 10.1172/JCI30178.
PubMed 17607354Gupta N, Singh T, Chaudhary R, Garg SK, Sandhu GS, Mittal V, Gupta R, Bodin R, Sule S. Bilirubin in coronary artery disease: Cytotoxic or protective? World J Gastrointest Pharmacol Ther. 2016 Nov 6;7(4):469-476. doi: 10.4292/wjgpt.v7.i4.469.
PubMed 27867680Kapitulnik J. Bilirubin: an endogenous product of heme degradation with both cytotoxic and cytoprotective properties. Mol Pharmacol. 2004 Oct;66(4):773-9. doi: 10.1124/mol.104.002832. Epub 2004 Jul 21. No abstract available.
PubMed 15269289Liao SL. The role of bilirubin and phototherapy in the oxidative/antioxidant balance. Pediatr Neonatol. 2015 Apr;56(2):77-8. doi: 10.1016/j.pedneo.2015.01.001. Epub 2015 Jan 22. No abstract available.
PubMed 25735960Wu TW, Fung KP, Wu J, Yang CC, Weisel RD. Antioxidation of human low density lipoprotein by unconjugated and conjugated bilirubins. Biochem Pharmacol. 1996 Mar 22;51(6):859-62. doi: 10.1016/0006-2952(95)02395-x.
PubMed 8602883Cao L, Xue L, Luo DM. Lower serum bilirubin concentration in patients with migraine. Int J Clin Exp Med. 2015 Aug 15;8(8):13398-402. eCollection 2015.
PubMed 26550273
Study at a glance
From the registry record, last updated by the sponsor on 2 Jan 2018. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Reduced Serum Bilirubin Levels in Patients With Normal-tension Glaucoma
- ClinicalTrials.gov ID
- NCT03387306
- Acronym / sponsor ID
- 14783786
- Keywords
- serum bilirubin, normal-tension glaucoma, oxidative stress
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 76 participants (actual)
- Lead sponsor
- Trakya UniversityUniversity, hospital or other
- Study start
- Jan 2010 (actual)
- Primary completion
- Mar 2017 (actual)
- Study completion
- Apr 2017 (actual)
- First posted
- 2 Jan 2018 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Purpose: To analyze the relationship between normal-tension glaucoma (NTG) and serum bilirubin levels.
Materials and Methods: This research included 38 patients with NTG and 38 healthy controls with similar age and sex distribution, for a total of 76 subjects. Serum samples were taken from all of the subjects, direct serum bilirubin, indirect serum bilirubin and the total serum bilirubin were measured.
Detailed description
This is a retrospective study of cases with recently or previously diagnosed NTG who were admitted to our clinic between 2010 and 2017. This study included 38 patients with NTG and 38 healthy controls with similar age and sex distribution, for a total of 76 subjects. Written informed consent was obtained from all of the participants. The study was approved by the institutional review board of the hospital and adhered to the tenets of the Declaration of Helsinki.
A complete ophthalmic examination including best-corrected visual acuity, slit-lamp biomicroscopy, Goldmann applanation tonometry (AT 900, Haag-Streit Diagnostics, Koeniz, CH), corneal thickness evaluation (Pachymeter SP-3000, Tomey Corporation, Nagoya, JP), gonioscopy and ophthalmoscopy was performed in all NTG cases. Additionally, optical coherence tomography (OCT RS-3000 Lite, NIDEK Corporation, Tokyo, JP) measurement of the peripapillary retinal nerve fibre layer thickness, and Humprey visual field testing (Carl-Zeiss Meditec, Dublin, CA) were also performed.
NTG was diagnosed based on a clinical examination showing a normal IOP (corrected for corneal thickness), thinning of the peripapillary retinal nerve fibre layer, optic nerve damage, and characteristic glaucomatous visual field defects. The exclusion criteria included other forms of glaucoma such as primary open-angle glaucoma, primary closed-angle glaucoma, pigmentary glaucoma and exfoliative glaucoma. Patients who had active systemic diseases such as those affecting the liver, biliary system, pancreas and kidney and infectious diseases or malignant tumours that could influence the serum bilirubin concentrations were also excluded.
Fasting blood samples were taken from each participant to measure direct bilirubin, indirect bilirubin, and the total serum bilirubin concentrations. The direct bilirubin and total bilirubin concentrations were measured with an Architect C16000 Clinical Chemistry Analyzer (Abbott Laboratories, Abbott Park, IL, USA), using its original kits, and the indirect bilirubin concentrations were calculated by the following formula: indirect bilirubin = total bilirubin - direct bilirubin.
All the data were compiled into a computer file, and Statistical Package for Social Sciences for Windows 22.0 was used to perform the statistical analysis. Student's t test or the Mann-Whitney U test were used to compare the mean values between the two groups, after the evaluation of the data for a normal distribution using the Kolmogorov-Smirnov test. A p value less than 0.05 was considered statistically significant.
Study design
- Observational model
- Case-control
- Time perspective
- Retrospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Patient group | – | –This grup included 38 patients with NTG. |
| Control group | – | –This group included 38 healthy controls. |
Who may qualify
- Ages
- 18 to 80 years
- Sex
- All
- Age groups
- Adult, Older adult
- Study population
- NTG was diagnosed based on a clinical examination showing a normal IOP (corrected for corneal thickness), thinning of the peripapillary retinal nerve fibre layer, optic nerve damage, and characteristic glaucomatous visual field defects. The exclusion criteria included other forms of glaucoma such as primary open-angle glaucoma, primary closed-angle glaucoma, pigmentary glaucoma and exfoliative glaucoma. Patients who had active systemic diseases such as those affecting the liver, biliary system, pancreas and kidney and infectious diseases or malignant tumours that could influence the serum bilirubin concentrations were also excluded.
Key inclusion criteria (1 listed)
- Healthy volunteers
Key exclusion criteria (1 listed)
- Patients who had active systemic diseases such as those affecting the liver, biliary system, pancreas and kidney and infectious diseases or malignant tumours that could influence the serum bilirubin concentrations were excluded.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Serum Bilirubin Levels
Time frame: January 2017-March 2017
Serum indirect, direct and total bilirubin levels
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 2 Jan 2018.
- Results publication: PubMed 24974815Tham YC, Li X, Wong TY, Quigley HA, Aung T, Cheng CY. Global prevalence of glaucoma and projections of glaucoma burden through 2040: a systematic review and meta-analysis. Ophthalmology. 2014 Nov;121(11):2081-90. doi: 10.1016/j.ophtha.2014.05.013. Epub 2014 Jun 26.
- Results publication: PubMed 17998042Flammer J, Mozaffarieh M. What is the present pathogenetic concept of glaucomatous optic neuropathy? Surv Ophthalmol. 2007 Nov;52 Suppl 2:S162-73. doi: 10.1016/j.survophthal.2007.08.012.
- Results publication: PubMed 27413503Mallick J, Devi L, Malik PK, Mallick J. Update on Normal Tension Glaucoma. J Ophthalmic Vis Res. 2016 Apr-Jun;11(2):204-8. doi: 10.4103/2008-322X.183914.
- Results publication: PubMed 24837853Cho HK, Kee C. Population-based glaucoma prevalence studies in Asians. Surv Ophthalmol. 2014 Jul-Aug;59(4):434-47. doi: 10.1016/j.survophthal.2013.09.003. Epub 2014 May 13.
- Results publication: PubMed 15350316Iwase A, Suzuki Y, Araie M, Yamamoto T, Abe H, Shirato S, Kuwayama Y, Mishima HK, Shimizu H, Tomita G, Inoue Y, Kitazawa Y; Tajimi Study Group, Japan Glaucoma Society. The prevalence of primary open-angle glaucoma in Japanese: the Tajimi Study. Ophthalmology. 2004 Sep;111(9):1641-8. doi: 10.1016/j.ophtha.2004.03.029.
- Results publication: PubMed 10653426Cursiefen C, Wisse M, Cursiefen S, Junemann A, Martus P, Korth M. Migraine and tension headache in high-pressure and normal-pressure glaucoma. Am J Ophthalmol. 2000 Jan;129(1):102-4. doi: 10.1016/s0002-9394(99)00289-5.
- Results publication: PubMed 10393040Henry E, Newby DE, Webb DJ, O'Brien C. Peripheral endothelial dysfunction in normal pressure glaucoma. Invest Ophthalmol Vis Sci. 1999 Jul;40(8):1710-4.
- Results publication: PubMed 26514963Himori N, Kunikata H, Shiga Y, Omodaka K, Maruyama K, Takahashi H, Nakazawa T. The association between systemic oxidative stress and ocular blood flow in patients with normal-tension glaucoma. Graefes Arch Clin Exp Ophthalmol. 2016 Feb;254(2):333-41. doi: 10.1007/s00417-015-3203-z. Epub 2015 Oct 30.
- Results publication: PubMed 19763599Yuki K, Murat D, Kimura I, Ohtake Y, Tsubota K. Reduced-serum vitamin C and increased uric acid levels in normal-tension glaucoma. Graefes Arch Clin Exp Ophthalmol. 2010 Feb;248(2):243-8. doi: 10.1007/s00417-009-1183-6. Epub 2009 Sep 8.
- Results publication: PubMed 17607354Harada T, Harada C, Nakamura K, Quah HM, Okumura A, Namekata K, Saeki T, Aihara M, Yoshida H, Mitani A, Tanaka K. The potential role of glutamate transporters in the pathogenesis of normal tension glaucoma. J Clin Invest. 2007 Jul;117(7):1763-70. doi: 10.1172/JCI30178.
- Results publication: PubMed 27867680Gupta N, Singh T, Chaudhary R, Garg SK, Sandhu GS, Mittal V, Gupta R, Bodin R, Sule S. Bilirubin in coronary artery disease: Cytotoxic or protective? World J Gastrointest Pharmacol Ther. 2016 Nov 6;7(4):469-476. doi: 10.4292/wjgpt.v7.i4.469.
- Results publication: PubMed 15269289Kapitulnik J. Bilirubin: an endogenous product of heme degradation with both cytotoxic and cytoprotective properties. Mol Pharmacol. 2004 Oct;66(4):773-9. doi: 10.1124/mol.104.002832. Epub 2004 Jul 21. No abstract available.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Sadık Altan Ozal principal investigator
Trakya University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Normal Tension Glaucoma and Bilirubin; Defect, Excretion, run by Trakya University at 1 site in Turkey (Türkiye).
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 1 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 2 Jan 2018. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Turkey (Türkiye). Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Serum Bilirubin Levels (time frame: January 2017-March 2017). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT03387306, which also lists 19 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 2 Jan 2018; AzTrials last refreshed its copy on 5 Nov 2026.