1Graduate Group of Biostatistics, Department of Statistics, University of California, Davis, CA, USA
2Department of Preventive Medicine, Jeonbuk National University Medical School, Jeonju, Korea
3Department of Endocrinology and Metabolism, Ajou University School of Medicine, Suwon, Korea
4Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea
5Department of Orthopedic Surgery, Seoul Sacred Heart General Hospital, Seoul, Korea
6University of North Carolina Kidney Center & Division of Nephrology and Hypertension, School of Medicine, University of North Carolina, Chapel Hill, NC, USA
7Division of Biostatistics, Department of Public Health Sciences, University of California, Davis, CA, USA
8Clinical and Translational Science Center & Center for Healthcare Policy and Research, Davis School of Medicine, University of California, Sacramento, CA, USA
Copyright © 2022 Korean Diabetes Association
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
CONFLICTS OF INTEREST
No potential conflict of interest relevant to this article was reported.
AUTHOR CONTRIBUTIONS
Conception or design: L.M., H.B.
Acquisition, analysis, or interpretation of data: L.M., K.S.K., J.K., H.B.
Drafting the work or revising: K.S.K., D.J.K., Y.L., J.K., A.V.K.
Final approval of the manuscript: L.M., K.S.K., D.J.K., Y.L., J.K., A.V.K., H.B.
FUNDING
Heejung Bang is partly supported by the National Institutes of Health through grant UL1 TR001860. The funding source had no role in the study design or implementation.
Characteristic | US population in NHANES (n=11,000)a | Korean population in KNHANES (n=18,560)a | |
---|---|---|---|
Age, yr | 47.7±0.39 | 47.3±0.24 | |
Women, % | 51.8 | 50.2 | |
BMI, kg/m2 | 29.6±0.18 | 24.0±0.04 | |
BMI/obesity status (based on USA/Asian criteria) | |||
BMI <25/BMI <23 kg/m2 | 28.5/17.3 | 65.0/42.6 | |
25≤ BMI <30/23≤ BMI <27.5 kg/m2 | 31.0/27.0 | 29.3/42.8 | |
30≤ BMI <40/27.5≤ BMI <35 kg/m2 | 32.3/36.9 | 5.5/13.7 | |
BMI ≥40/BMI ≥35 kg/m2 | 8.2/18.8 | 0.1/0.8 | |
Waist (women/men), inches | 38.7±0.23/40.4±0.21 | 30.9±0.06/33.9±0.05 | |
Hypertension, % | 38.7 | 28.6 | |
Prehypertension, % | 42.8 | 41.6 | |
SBP/DBP, mm Hg | 123.7±0.32/71.2±0.37 | 117.7±0.19/75.8±0.12 | |
Family history of DM, % | 42.0 | 23.3 | |
Known DM, % | 12.1 | 7.7 | |
Known kidney disease (kidney weak, failure, or dialysis), % | 3.2 | 0.26/0.06–0.21b | |
Physically inactive, % | 58.3 | 57.0 | |
Gestational diabetes (among women), % | 6.6 | Unavailable | |
Current smoker, % | 24.1 | 21.4 | |
Alcohol, light or moderate/heavy, % | 46.9/26.3c | 34.2/16.7c | |
Anemia treatment, % | 3.8 | Unavailable | |
Hemoglobin, g/dL | 14.2±0.04 | 14.2±0.02 | |
Cardiovascular disease, % | 7.4 | 3.6 | |
(Congestive) heart failure, % | 2.3 | Unavailable | |
Proteinuria, % | 9.9 | 12.7 | |
Outcomes-related | |||
Fasting glucose (at least 8 hours), mg/dL | 109.6±0.61 | 99.8±0.23 | |
Hemoglobin HbA1c, % | 5.7±0.02 | 5.6±0.01 | |
2-hour glucose, mg/dL | 117.1±1.28c | Unavailable | |
DM (based on lab tests), % | 11.0 | 10.0 | |
Pre-DM (based on lab tests), % | 31.5 | 34.3 | |
Undiagnosed DM (no. of newly diagnosed DM/no. of total DM), % | 20.1 | 34.1 | |
Creatinine, mg/dL | 0.87±0.005 | 0.83±0.002 | |
eGFR, mL/min/1.73 m2 | 94.9±0.58 | 97.8±0.23/98.9±0.23d | |
eGFR <60 mL/min/1.73 m2, % | 6.8 | 2.7/2.9d |
Values are presented as mean±standard error.
NHANES, National Health and Nutrition Examination Survey; KNHANES, Korea National Health and Nutrition Examination Survey; BMI, body mass index; SBP, systolic blood pressure; DBP, diastolic blood pressure; HbA1c, glycosylated hemoglobin; DM, diabetes mellitus; eGFR, estimated glomerular filtration rate.
a Before excluding known/already diagnosed DM and chronic kidney disease (CKD) cases. Sample sizes (number) are unweighted, while other summary statistics are weighted (following NHANES/KNHANES analysis guidelines),
b Left/right values are because weak kidney was not asked/when we included eGFR <15 to <30 mL/min/1.73 m2 (note that creatinine was missing among 707 participants in KNHANES),
c Due to different assessments, % may not be comparable in the two countries,
d Left/right values are when USA/Korean Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formulas were used. See Appendix 1 for variable definitions.
USA-DM score in NHANES (428 DM cases, n=8,928; AUC=0.753) |
K-DM score in KNHANES (791 DM cases, n=16,209; AUC=0.766) |
||||
---|---|---|---|---|---|
Predictor (assigned score) | OR (95% CI) | P valueb | Predictor (assigned score) | OR (95% CI) | P value |
Age, yr | Age, yr | ||||
40–49 (1) | 2.68 (1.83–3.93) | <0.001 | 35–44 (2) | 3.07 (2.00–4.71) | <0.001 |
50–59 (2) | 4.65 (3.25–6.64) | <0.001 | ≥45 (3) | 5.27 (3.54–7.84) | <0.001 |
≥60 (3) | 4.96 (3.52–6.99) | <0.001 | c | ||
Male (1) | 1.29 (1.05–1.58) | 0.012 | c | ||
Hypertension (1) | 1.49 (1.20–1.86) | <0.001 | Hypertension (1) | 2.03 (1.74–2.38) | <0.001 |
Family DM (1) | 1.29 (1.06–1.58) | 0.013 | Family DM (1) | 1.83 (1.55–2.15) | <0.001 |
BMI, kg/m2 | Waist, inches | ||||
25–29.9 (1) | 1.23 (0.90–1.69) | 0.194 | 30–32.9/33–34.9 (F/M) (2) | 1.77 (1.40–2.23) | <0.001 |
30–39.9 (2) | 2.65 (1.99–3.53) | <0.001 | ≥33/35 (F/M) (3) | 3.84 (3.13–4.72) | <0.001 |
≥40 (3) | 3.83 (2.63–5.59) | <0.001 | c | ||
Physically inactive (1) | 1.36 (1.09–1.69) | 0.006 | Current smoker (1) | 1.43 (1.18–1.73) | <0.001 |
Gestational DM, women only (1) | 2.46 (1.53–3.95) | <0.001 | Alcohol, drinks/day | ||
Light or moderate, 1–4.9 (1) | 0.92 (0.77–1.11) | 0.387 | |||
Heavy, ≥5 (2) | 1.17 (0.95–1.44) | 0.137 |
DM, diabetes mellitus; NHANES, National Health and Nutrition Examination Survey; AUC, area under the receiver operating characteristic (ROC) curve; KNHANES, Korea National Health and Nutrition Examination Survey; OR, odds ratio; CI, confidence interval; BMI, body mass index.
a NHANES 2015–2018 and KNHANES 2016–2018 among adults (≥19 year old) were used. For DM, known DM were excluded. Prediction equations are in Supplementary Table 4,
b P value is calculated with chi-square test,
c Empty cells are due to different questions included in different questionnaires.
USA-CKD score in NHANES (664 CKD cases, n=9,890; AUC=0.893) |
K-CKD score in KNHANES (653 CKD cases, n=17,803; AUC=0.912) |
||||
---|---|---|---|---|---|
Predictor (assigned score) | OR (95% CI) | P value | Predictor (assigned score) | OR (95% CI) | P value |
Age, yr | Age, yr | ||||
50–59 (2) | 5.54 (3.10–9.90) | <0.001 | 50–59 (2) | 5.41 (2.79–10.5) | <0.001 |
60–69 (3) | 20.3 (12.1–34.0) | <0.001 | 60–69 (3) | 17.1 (9.31–31.2) | <0.001 |
≥70 (4) | 73.3 (44.3–121) | <0.001 | ≥70 (4) | 59.9 (33.2–108) | <0.001 |
Female (1) | 1.19 (0.99–1.42) | 0.065 | Female (1) | 0.74 (0.62–0.88) | <0.001b |
Hypertension (1) | 1.50 (1.21–1.87) | <0.001 | Hypertension (1) | 2.24 (1.81–2.76) | <0.001 |
DM (1) | 1.12 (0.92–1.35) | 0.264c | DM (1) | 2.00 (1.67–2.39) | <0.001 |
Anemia (1) | 2.04 (1.48–2.81) | <0.001 | Anemia (1) | 4.09 (3.36–4.99) | <0.001 |
CVD (1) | 1.54 (1.23–1.92) | <0.001 | CVD (1) | 1.36 (1.07–1.73) | 0.011 |
CHF or HF (1) | 1.65 (1.20–2.27) | 0.002 | d | ||
PAD (1) | Unavailable | d | |||
Proteinuria (1) | 1.89 (1.54–2.33) | <0.001 | Proteinuria (1) | 2.32 (1.88–2.85) | <0.001 |
CKD, chronic kidney disease; NHANES, National Health and Nutrition Examination Survey; AUC, area under the receiver operating characteristic (ROC) curve; KNHANES, Korea National Health and Nutrition Examination Survey; OR, odds ratio; CI, confidence interval; DM, diabetes mellitus; CVD, cardiovascular disease; CHF, congestive heart failure; HF, heart failure; PAD, peripheral artery disease (or circulation problems in legs in the questionnaire).
a NHANES 2015–2018 and KNHANES 2016–2018 among adults (≥19 year old) were used. For CKD, known kidney failure/disease were excluded. Prediction equations are in Supplementary Table 4,
b When Korean Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) was used, there were 697 CKD cases, and “female” showed OR, 1.10 (95% CI, 0.93 to 1.31; P=0.27 and AUC=0.907),
c Is due to multicollinearity; DM showed unadjusted OR, 2.95 (95% CI, 2.50 to 3.48; P<0.001), and OR, 1.23 (95% CI, 1.02 to 1.48; P=0.029) when proteinuria was excluded. For DM, total DM (i.e., diagnosed and undiagnosed together) was used. When only known/diagnosed DM was used, results did not change materially; beta coefficient was slightly attenuated but AUC was unchanged (i.e., second or third decimal point change),
d Empty cells are due to different questions included in different questionnaires.
Model, population | % of high score | Se | Sp | PPV | NPV | LR+ | LR– | Youden | AUC | |
---|---|---|---|---|---|---|---|---|---|---|
Outcome: undiagnosed DM (cutpoint ≥5 for high risk) | ||||||||||
USA-DM score, in NHANES | 48 | 84 | 53 | 8 | 99 | 1.79 | 0.30 | 37 | 0.75 | |
USA-DM score, in KNHANES | 31 | 67 | 70 | 10 | 98 | 2.23 | 0.47 | 37 | 0.78 | |
K-DM score, in KNHANES | 57 | 89 | 45 | 8 | 99 | 1.62 | 0.24 | 34 | 0.77 | |
K-DM score, in NHANES | 72 | 93 | 29 | 6 | 99 | 1.31 | 0.24 | 22 | 0.71 | |
USA-DM score for DM/pre-DM, in NHANESb | 49 | 70 | 66 | 59 | 76 | 2.06 | 0.45 | 36 | 0.73 | |
USA-DM score for DM/pre-DM, in KNHANESb | 31 | 48 | 82 | 68 | 67 | 2.67 | 0.63 | 30 | 0.75 | |
Outcome: undiagnosed CKD (cutpoint ≥4 for high risk) | ||||||||||
USA-CKD score, in NHANES | 39 | 94 | 65 | 16 | 99 | 2.69 | 0.09 | 59 | 0.89 | |
USA-CKD score, in KNHANES | 38 | 96 | 64 | 9 | 100 | 2.67 | 0.06 | 60 | 0.91 | |
K-CKD score, in KNHANES | 38 | 96 | 64 | 9 | 100 | 2.67 | 0.06 | 60 | 0.91 | |
K-CKD score, in NHANES | 39 | 94 | 65 | 16 | 99 | 2.69 | 0.09 | 59 | 0.89 |
DM, diabetes mellitus; CKD, chronic kidney disease; Se, sensitivity; Sp, specificity; PPV, positive predictive value; NPV, negative predictive value; LR+, likelihood ratio positive; LR–, likelihood ratio negative; AUC, area under the ROC curve; NHANES, National Health and Nutrition Examination Survey; KNHANES, Korea National Health and Nutrition Examination Survey.
a NHANES 2015–2018 and KNHANES 2016–2018 data among adults (≥19 year old) were used. For DM (and DM/pre-DM), known DM were excluded. For CKD, known kidney failure or disease were excluded,
b 3,767 had DM/pre-DM among 8,743 in NHANES and 7,144 had DM/pre-DM among 16,148 in KNHANES. Of note, denominators are slightly reduced due to the fact that persons with unknown DM/pre-DM status were excluded.
NHANES, National Health and Nutrition Examination Survey; KNHANES, Korea National Health and Nutrition Examination Survey; DM, diabetes mellitus; eGFR, estimated glomerular filtration rate; HbA1c, glycosylated hemoglobin; CKD-EPI, Chronic Kidney Disease Epidemiology Collaboration; MDRD, Modification of Diet in Renal Disease; KDIGO, Kidney Disease: Improving Global Outcomes.