Volume overload and its risk factors in South African chronic kidney disease patients: an appraisal of bioimpedance spectroscopy and inferior vena cava measurements.
BACKGROUND
Fluid retention occurs early in chronic kidney disease (CKD) resulting in increased cardiovascular morbidity and mortality. This study aimed to assess volume and nutritional status among South African CKD participants and determine the relationship between malnutrition, inflammation, atherosclerosis, and volume overload using a body composition monitor (BCM). We also evaluated the usefulness of BCM measurement in assessing volume overload.


METHODS
160 participants comprising hemodialysis, peritoneal dialysis, stage 3 CKD patients, and healthy controls (40 in each group) were studied. A BCM was used to assess fluid and nutritional status. Cardiac dimension measurements, and inferior vena cava diameter (IVCD) and carotid intima media thickness were assessed by echocardiography and ultrasonography, respectively. Serum interleukin-6 (IL-6) and C-reactive protein (CRP) levels were measured as markers of inflammation.


RESULTS
Fluid overload and malnutrition were present in 68% and 63% of studied patients, respectively. Using physical examination findings as the reference measurements for volume overload, the area under the concentration curves for BCM and IVCD measurements were 0.866 (sensitivity 82%, specificity 74%, p < 0.001) and 0.727 (sensitivity 57%, specificity 70%, p < 0.001), respectively. Lean tissue index, inflammation, and atherosclerosis were associated with volume overload.


CONCLUSIONS
Volume overload and malnutrition were common across the spectrum of South African CKD cohorts; volume overload was associated with malnutrition, inflammation, and atherosclerosis. Bioimpedance spectroscopy (BIS) is a useful and sensitive tool for the assessment of fluid status in clinically euvolumic nondialytic CKD patients.
Muzamil Olamide
MO
Hassan
Raquel
R
Duarte
Therese
T
Dix-Peek
Ahmed
A
Vachiat
Caroline
C
Dickens
Sacha
S
Grinter
Sagren
S
Naidoo
Pravin
P
Manga
Saraladevi
S
Naicker
D000328:Adult; D050197:Atherosclerosis / Q000150:complications / Q000209:etiology; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000378:metabolism; D059168:Carotid Intima-Media Thickness; D004452:Echocardiography; D017097:Electric Impedance; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging; D006801:Humans; D007249:Inflammation / Q000097:blood / Q000209:etiology; D015850:Interleukin-6 / Q000097:blood; D008297:Male; D044342:Malnutrition / Q000175:diagnosis*; D008875:Middle Aged; D009752:Nutritional Status; D010530:Peritoneal Dialysis / Q000009:adverse effects; D006435:Renal Dialysis / Q000009:adverse effects*; D051436:Renal Insufficiency, Chronic / Q000150:complications / Q000628:therapy*; D012307:Risk Factors; D013019:South Africa; D013057:Spectrum Analysis; D014682:Vena Cava, Inferior / Q000000981:diagnostic imaging*; D014883:Water-Electrolyte Imbalance
D015415:Biomarkers; D015850:Interleukin-6; D002097:C-Reactive Protein