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Published on: July 3, 2013
Changes in osmol gap in chronic kidney disease: an exploratory study.
Gulvahid Shaikh1, Rahul Sehgal, Sukhdeep Sandhu
1Department of Medicine, Division of Nephrology and Hypertension, Nassau University Medical Center , East Meadow, NY , USA and.
The osmol gap (OG) increases with chronic kidney disease (CKD) progression and is elevated in patients undergoing maintenance hemodialysis (HD). Hemodialysis effectively normalizes the osmol gap, suggesting its utility in assessing CKD stage and dialysis adequacy.
Area of Science:
- Nephrology
- Clinical Chemistry
Background:
- Limited data exists on osmol gap (OG) in chronic kidney disease (CKD) by stage.
- Data on OG in adults on maintenance hemodialysis (HD) is scarce.
Purpose of the Study:
- To investigate the trend of OG across different stages of CKD.
- To compare pre- and post-hemodialysis OG in patients on maintenance HD.
Main Methods:
- A cross-sectional study involving 67 patients.
- Patients were categorized into six groups: normal renal function, CKD stages 2-5 (non-dialysis), and maintenance HD.
- Osmol gap was measured in all groups, with pre- and post-HD measurements for the HD group.
Main Results:
- A statistically significant upward trend in OG was observed with increasing CKD stage (p < 0.001).
- Patients on maintenance HD exhibited significantly higher OG compared to reference and CKD groups (p < 0.001).
- Hemodialysis significantly reduced OG in the HD group (p < 0.001).
Conclusions:
- Osmol gap demonstrates a significant positive correlation with CKD stage.
- Elevated OG in maintenance HD patients is normalized post-dialysis.
- OG may serve as a valuable biomarker for CKD staging and dialysis adequacy assessment.
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