Change in the distribution of albuminuria according to estimated glomerular filtration rate in Pima Indians with type 2 diabetes.
OBJECTIVE
We examined secular trends in the frequency distribution of albuminuria and estimated glomerular filtration rate (eGFR) in subjects with type 2 diabetes in 1982-1988 and 2001-2006, two periods associated with major changes in the management of diabetes.


METHODS
The cross-sectional study included Pima Indians > or =15 years old with type 2 diabetes and measures of serum creatinine and urinary albumin-to-creatinine ratios (ACR). The continuous probability density distributions of ACR and eGFR were compared for the two time periods. eGFR was calculated using the Modification of Diet in Renal Disease Study equation.


RESULTS
The overall standardized distribution of ACR shifted toward lower values between time periods (P = 0.001), whereas the standardized distribution of eGFR did not (P = 0.45). In the first period, eGFR was <60 ml/min per 1.73 m(2) in 6.5% of the 837 subjects. Of these, 9.3% had normal ACR, 7.4% had microalbuminuria, and 83.3% had macroalbuminuria. In the second period, the prevalence of low eGFR was similar (6.6% of the 1,310 subjects). Among those with low eGFR, normal ACR prevalence doubled to 17.2%, microalbuminuria prevalence nearly tripled to 19.5%, and macroalbuminuria prevalence declined to 63.2%. Twice as many subjects in the second period received antihypertensive medicines and 30% more received hypoglycemic medicines than in the first period.


CONCLUSIONS
The distribution of albuminuria changed significantly among diabetic Pima Indians over the past 20 years, as treatment with medicines to control hyperglycemia and hypertension increased. The distribution of eGFR, however, remained unchanged. Consequently, the frequency of chronic kidney disease characterized by normoalbuminuria and low eGFR doubled.
Pavkov
Meda E
ME
Diabetes Epidemiology and Clinical Research Section, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Phoenix, Arizona, USA. mpavkov@cdc.gov
Mason
Clinton C
CC
Bennett
Peter H
PH
Curtis
Jeffrey M
JM
Knowler
William C
WC
Nelson
Robert G
RG
D000328:Adult; D000419:Albuminuria / Q000503:physiopathology*; D003404:Creatinine / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology*; D005260:Female; D005919:Glomerular Filtration Rate / Q000502:physiology*; D006801:Humans; D007198:Indians, North American; D007674:Kidney Diseases / Q000209:etiology; D008297:Male; D008875:Middle Aged
D003404:Creatinine