Iron indices in chronic kidney disease in the National Health and Nutritional Examination Survey 1988-2004.
OBJECTIVE
Anemia is a common and early complication of nondialysis chronic kidney disease (CKD). One contributing factor is iron deficiency, which may be particularly problematic during erythropoietin replacement therapy. The aim of this study was to examine the prevalence of iron deficiency in nondialysis CKD.


METHODS
The National Health and Nutritional Examination Survey (NHANES) data for NHANES III (1988 to 1994) and subsequent NHANES 2-yr datasets, 1999 to 2000, 2001 to 2002, and 2003 to 2004 were analyzed for individuals >18 yr old.


RESULTS
It was found that low levels of iron tests [either serum ferritin < 100 ng/ml or transferrin saturation (TSAT) < 20%] were present in most patients with reduced creatinine clearance (CrCl). The percentage of low iron tests was higher among women than men, present in 57.8 to 58.8% of men and 69.9 to 72.8% of women (P < 0.001). With declining levels of CrCl, in women, TSAT levels decreased, whereas, surprisingly, serum ferritin tended to progressively increase. The percentage of anemic subjects increased progressively with declining quartiles of TSAT but was unrelated to serum ferritin quartiles.


CONCLUSIONS
It was found that low levels of iron tests, following National Kidney Foundation/Kidney Disease Outcomes Quality Initiative guidelines (either serum ferritin < 100 ng/ml or TSAT < 20%) were present in most patients with reduced CrCl.
Fishbane
Steven
S
Winthrop University Hospital, Mineola, NY 11501, USA. sfishbane@metrorenal.com
Pollack
Simcha
S
Feldman
Harold I
HI
Joffe
Marshall M
MM
D000328:Adult; D018798:Anemia, Iron-Deficiency / Q000097:blood / Q000188:drug therapy / Q000453:epidemiology / Q000209:etiology*; D015415:Biomarkers / Q000097:blood; D002908:Chronic Disease; D003404:Creatinine / Q000097:blood; D005260:Female; D005293:Ferritins / Q000097:blood; D006306:Health Surveys; D006397:Hematinics / Q000627:therapeutic use; D006801:Humans; D000090463:Iron Deficiencies; D007674:Kidney Diseases / Q000097:blood / Q000150:complications* / Q000188:drug therapy / Q000453:epidemiology; D008297:Male; D009749:Nutrition Surveys; D017410:Practice Guidelines as Topic; D015995:Prevalence; D012720:Severity of Illness Index; D013997:Time Factors; D014168:Transferrin / Q000378:metabolism; D014481:United States / Q000453:epidemiology
D015415:Biomarkers; D006397:Hematinics; D014168:Transferrin; D005293:Ferritins; D003404:Creatinine