The adjusted cardiovascular mortality rate among non-institutionalized U.S. adult residents aged 20+ with CKD stage 3 and 4 and macroalbuminuria in 1988-1994 was 41 per 1,000 person-years; those with normal kidney function and no albuminuria had a rate of 5 per 1,000 person-years.
Albuminuria appeared to be more strongly associated with cardiovascular mortality than reduced eGFR.
Chart Explanation: Through 2000, the overall incidence of cardiovascular mortality among U.S. residents aged 20 years or older who had normal kidney function and microalbuminuria or macroalbuminuria in 1988-1994 were 10 and 19 per 1,000 person-years, respectively, compared to those with normal kidney function and no albuminuria (5 per 1,000 person-years). Those with eGFRs of 60-89 ml/min/1.73 m² and microalbuminuria or macroalbuminuria (CKD stage 2) had incidence of cardiovascular mortality of 13 and 24 per 1,000 person-years, respectively, compared to those with no albuminuria (6 per 1,000 person-years). Similarly, those with eGFRs of 15-59 ml/min/1.73 m² (CKD stages 3 and 4) and microalbuminuria or macroalbuminuria had incidence of 24 and 41 per 1,000 person-years, respectively, compared to those with no albuminuria (11 per 1,000 person-years).
The NHANES (National Health and Nutrition Examination Survey) is a nationally representative, cross-sectional survey that is conducted by the National Center for Health Statistics to examine disease prevalence and trends over time in non-institutionalized U.S. civilian residents. The National Death Index (NDI) tracks all mortality in the United States through state death certificates.
The NHANES III survey was conducted from 1988 to 1994 by the National Center for Health Statistics to examine disease prevalence and trends over time in cross-sectional representative samples of non-institutionalized U.S. civilian residents. The survey consists of a standardized in-home interview and a physical examination and blood and urine collection at a mobile examination center (MEC). These data have been linked to data from the National Death Index (http://www.cdc.gov/nchs/ndi.htm), which tracks mortality data from death certificates provided by each state, and both all-cause and cardiovascular mortality through 2000 by participants’ eGFR and albuminuria were examined (Astor et al., 2008). Albuminuria as measured by the albumin:creatinine ratio, was categorized as: normal, <30 mg/g; microalbuminuria, 30-299 mg/g; and macroalbuminuria, >300 mg/g.
|Description of Measure||Proportion moving to ESRD over time|
|Type of Data Source||Public; restricted use|
|Data Set||NHANES III/CMS|
|Health Care System Data||No|
|Regional or National?||National|
|Demographic Group||Non-institutionalized U.S. residents aged 20+ years|
|Numerator||Participants with CKD who subsequently initiated treatment for ESRD (as captured by Medicare Enrollment Database)|
|Denominator||All participants with CKD|
|Definition of CKD||eGFR ≥ 90 ml/min/1.73 m² and estimated persistent albuminuria; eGFR 60-89 ml/min/1.73 m² and estimated persistent albuminuria; Stage 3, eGFR 30-59 ml/min/1.73 m²; Stages 4&5, eGFR <29 ml/min/1.73 m²|
|Glomerular filtration rate||Estimated using MDRD Study equation: eGFR=186 × [(serum creatinine in mg/dl)-1.154] × age-0.203 × (0.742 if female) × (1.210 if African-American)|
|Proteinuria||Urinary albumin-to-creatinine ratios of 17-250 (male) and 25-355 (female) mg/g (microalbuminuria) and >250/>355 mg/g (macroalbuminuria)|
|Primary Data Source Indicator||Initiation of dialysis treatment in 1991-2000|
|Primary Indicator Method of Measurement||Claims from Medicare Enrollment Database|
|Secondary (1) Variable||lbxscr: Serum creatinine (NHANES III)|
|Secondary (1) Indicator Method of Measurement||Examination/Laboratory|
|Secondary (2) Variable||ridageyr: Age in years (NHANES III)|
|Secondary (2) Indicator Method of Measurement||Questionnaire (interviewer-administered)|
|Secondary (3) Variable||ridgendr: Gender (NHANES III)|
|Secondary (3) Indicator Method of Measurement||Questionnaire (interviewer-administered)|
|Secondary (4) Variable||ridreth1: Race/ethnicity (NHANES III)|
|Secondary (4) Indicator Method of Measurement||Questionnaire (interviewer-administered)|
|Secondary (5) Variable||urxuma: Urine albumin (NHANES III)|
|Secondary (5) Indicator Method of Measurement||Examination/lab|
|Secondary (6) Variable||urxucr: Urine creatinine (NHANES III)|
|Secondary (6) Indicator Method of Measurement||Examination/lab|
|Frequency of Measurement (Primary)||Once (cross-sectional)|
|U.S. Region Covered by Primary Variable||All|
|Period Currently Available||1988–2000|
|Pending Data||NHANES 1999-2006 linked with CMS, up to 2006|
|Additional Data Items of Interest||Stage of CKD, year, other stratification variables of interest (diabetes by self-report, hypertension by self-report)|
|Limitations of Indicator||Proteinuria can only be assessed from a one-time cross-sectional measurement for most participants; NHANES 1999-2006 not yet linked to CMS|
|Analytical Considerations||Appropriate NHANES survey weights must be used for all analyses; estimation of persistence of proteinuria can only be done at the population level; if SE 30% or more of estimate, must report as “low precision”|
References and Sources:
Astor BC, Hallan SI, Miller ER 3rd, Yeung E, Coresh J. Glomerular filtration rate, albuminuria, and risk of cardiovascular and all-cause mortality in the US population.Am J Epidemiol. 2008;167(10):1226-1234.