Prevalence of lack of health care insurance increased significantly during 2001–2004 to 2009–2012 and then decreased significantly through 2017–March 2020 among adults with or without CKD. During 2017–March 2020, 17.9% of adults with CKD reported that they did not have health insurance coverage as compared to 25.9% of adults in 2009–2012. This downward trend was also present among adults without CKD. After age standardization for both groups, the difference in lack of health care coverage appears larger, with higher prevalence of lack of coverage for adults with CKD compared with those without CKD, although not significantly different.
Age-standardized estimates were standardized to the 2010 U.S. Census population for adults (18–24 years, 25–44 years, and 45–64 years). The 2017–2020 cycle is till March 2020.
NHANES is a nationally representative, cross-sectional survey that is currently conducted every two years (since 1999) by CDC's National Center for Health Statistics among noninstitutionalized US civilian residents. The survey consists of a standardized in-home interview and a physical examination with blood and urine collected at a mobile examination center. Data were examined by combining two NHANES cycles to represent four-year periods from 2001 to 2016 and the 2017–March 2020 pre-pandemic cycle.
Note: Not all NHANES variables are collected for all years; therefore, some NHANES indicators may not utilize the full 20-year span.
Lack of health insurance among U.S. adults, by CKD.
National Health and Nutrition Examination Survey (NHANES).
Noninstitutionalized U.S. adults aged 18–64 years, pregnant women excluded.
2001–March 2020.
U.S. adults aged 18–64 years who self-reported having no health insurance or health care coverage.
U.S. adults aged 18–64 years with health insurance data and serum creatinine and urine albumin measurements. Those with missing health insurance data were excluded (<0.2%).
CKD was defined by an estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m² or albuminuria (urine albumin to creatinine ratio [UACR] ≥30 mg/g). Estimates were based on single estimates of eGFR and UACR.
Based on the CKD-EPI (2021) equation for calibrated creatinine: eGFR=142 x [min(serum creatinine in mg/dL) /κ, 1)]**α x [max(serum creatinine/κ, 1)]**-1.20 x 0.9938**age x (1.012 if female). κ = 0.7 if female and 0.9 if male α = -0.241 if female and -0.302 if male ** = raise to the power
UACR was calculated as urine albumin divided by urine creatinine. Albuminuria is defined as UACR ≥30 mg/g.
Serum creatinine values used for eGFR calculation were standardized against isotope dilution mass spectrometry.
Measured in random urine collection by fluorescent immunoassay.
Self-reported response of “No” to the question: “Covered by health insurance?”
Age-standardized estimates were standardized to the 2010 U.S. Census population for adults: 18–24 years: 15.8%, 25–44 years: 42.3%, and 45–64 years: 41.9%.
Albuminuria and kidney function were assessed from one-time cross-sectional measurements, possibly overestimating CKD prevalence.
Appropriate NHANES survey weights were used for all analyses; if the relative standard error was greater than 30%, the estimates are not shown. Serum creatinine measurements were assay corrected for NHANES years 2005 and 2006 and prior to being combined with later years.
