Relationship Between Glaucoma and Selenium Levels in Plasma and Aqueous Humor

Persistent Link:
http://hdl.handle.net/10150/195335
Title:
Relationship Between Glaucoma and Selenium Levels in Plasma and Aqueous Humor
Author:
Bruhn, Roberta L
Issue Date:
2008
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Purpose: To determine the association of plasma and aqueous humor selenium with glaucoma; and to determine those factors influencing biological levels of selenium in patients with glaucoma and cataractMethods: 47 primary open angle glaucoma (POAG) cases and 54 controls were recruited from surgery patients at the University Physician's Ophthalmology Clinic in Tucson, Arizona. Aqueous humor and plasma selenium concentration was determined by high performance liquid chromatography ion channel plasma-mass spectrometry (HPLC ICP-MS). Potential confounders were assessed via questionnaire. Outcome measures included the odds of glaucoma in relation to plasma selenium and aqueous humor selenium. Factors driving plasma and aqueous humor selenium in the study population were determined via linear regression.Results: After adjustment for risk factors and multiple outcomes, the odds of glaucoma in the highest tertile of plasma selenium (OR = 13.51; p=.03) and the middle tertile of aqueous humor selenium (OR = 0.05; p=0.02) were significantly associated with glaucoma. Selenium concentration in plasma and aqueous humor was primarily driven by metabolic factors (cancer, DMII, and ARMD).Conclusions: Although a causal pathway cannot be inferred from the analysis, it may be prudent to explore these relations in a larger sample in varying areas of geographic selenium distribution. Such information could be helpful in examining a larger study population and comparing biological data. Evaluating a subject's selenium levels over time and in relation to glaucoma onset could also lend pertinent informationDriving forces behind selenium concentrations in this population are mainly metabolic in nature. Selenium levels fluctuate in most tissue as it is metabolized by the body. Selenium supplementation is a significant predictor but this effect is small and may be transient as supplementation only temporarily increases selenium pools. It is interesting to note that sex is a significant predictor of aqueous humor selenium but not of plasma selenium. In this model, female sex predicts a decrease in the selenium within the aqueous humor. This point should be explored in future studies that are powered to discern possibly subtle differences that sex plays in relation to selenium concentrations in plasma and aqueous humor and its possible role in glaucoma.
Type:
text; Electronic Dissertation
Keywords:
epidemiology; glaucoma; selenium; aqueous humor
Degree Name:
PhD
Degree Level:
doctoral
Degree Program:
Epidemiology; Graduate College
Degree Grantor:
University of Arizona
Committee Chair:
Chen, Zhao

Full metadata record

DC FieldValue Language
dc.language.isoENen_US
dc.titleRelationship Between Glaucoma and Selenium Levels in Plasma and Aqueous Humoren_US
dc.creatorBruhn, Roberta Len_US
dc.contributor.authorBruhn, Roberta Len_US
dc.date.issued2008en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractPurpose: To determine the association of plasma and aqueous humor selenium with glaucoma; and to determine those factors influencing biological levels of selenium in patients with glaucoma and cataractMethods: 47 primary open angle glaucoma (POAG) cases and 54 controls were recruited from surgery patients at the University Physician's Ophthalmology Clinic in Tucson, Arizona. Aqueous humor and plasma selenium concentration was determined by high performance liquid chromatography ion channel plasma-mass spectrometry (HPLC ICP-MS). Potential confounders were assessed via questionnaire. Outcome measures included the odds of glaucoma in relation to plasma selenium and aqueous humor selenium. Factors driving plasma and aqueous humor selenium in the study population were determined via linear regression.Results: After adjustment for risk factors and multiple outcomes, the odds of glaucoma in the highest tertile of plasma selenium (OR = 13.51; p=.03) and the middle tertile of aqueous humor selenium (OR = 0.05; p=0.02) were significantly associated with glaucoma. Selenium concentration in plasma and aqueous humor was primarily driven by metabolic factors (cancer, DMII, and ARMD).Conclusions: Although a causal pathway cannot be inferred from the analysis, it may be prudent to explore these relations in a larger sample in varying areas of geographic selenium distribution. Such information could be helpful in examining a larger study population and comparing biological data. Evaluating a subject's selenium levels over time and in relation to glaucoma onset could also lend pertinent informationDriving forces behind selenium concentrations in this population are mainly metabolic in nature. Selenium levels fluctuate in most tissue as it is metabolized by the body. Selenium supplementation is a significant predictor but this effect is small and may be transient as supplementation only temporarily increases selenium pools. It is interesting to note that sex is a significant predictor of aqueous humor selenium but not of plasma selenium. In this model, female sex predicts a decrease in the selenium within the aqueous humor. This point should be explored in future studies that are powered to discern possibly subtle differences that sex plays in relation to selenium concentrations in plasma and aqueous humor and its possible role in glaucoma.en_US
dc.typetexten_US
dc.typeElectronic Dissertationen_US
dc.subjectepidemiologyen_US
dc.subjectglaucomaen_US
dc.subjectseleniumen_US
dc.subjectaqueous humoren_US
thesis.degree.namePhDen_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineEpidemiologyen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.chairChen, Zhaoen_US
dc.contributor.committeememberRanger-Moore, Jamesen_US
dc.contributor.committeememberStamer, W. Danielen_US
dc.contributor.committeememberGandolfi, A. Jayen_US
dc.identifier.proquest2669en_US
dc.identifier.oclc659749673en_US
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