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
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Characteristic | US population in NHANES (n=11,000) |
Korean population in KNHANES (n=18,560) |
|
---|---|---|---|
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 | 0.26/0.06–0.21 |
|
Physically inactive, % | 58.3 | 57.0 | |
Gestational diabetes (among women), % | 6.6 | Unavailable | |
Current smoker, % | 24.1 | 21.4 | |
Alcohol, light or moderate/heavy, % | 46.9/26.3 |
34.2/16.7 |
|
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±1.28 |
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±0.23 |
|
eGFR <60 mL/min/1.73 m2, % | 6.8 | 2.7/2.9 |
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 value |
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 | |||
Male (1) | 1.29 (1.05–1.58) | 0.012 | |||
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 | |||
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 |
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) | <0.001 |
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) | 0.264 |
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 | |||
PAD (1) | Unavailable | ||||
Proteinuria (1) | 1.89 (1.54–2.33) | <0.001 | Proteinuria (1) | 2.32 (1.88–2.85) | <0.001 |
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 NHANES |
49 | 70 | 66 | 59 | 76 | 2.06 | 0.45 | 36 | 0.73 | |
USA-DM score for DM/pre-DM, in KNHANES |
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 |
Variable | NHANES | KNHANES |
---|---|---|
Known DM (self-report) | Yes (Y) if doctor told you have diabetes, or taking insulin or diabetic treatment | |
Known kidney disease (self-report) | Y if ever told you had weak/failing kidneys, or received dialysis in past 12 mo | Y if kidney failure diagnosis or treatment |
Body mass index | Derived from measured weight (kg) divided by measured height2 (m2) (note: NHANES additionally collected self-reported weight and height and obesity status [i.e., normal or overweight], and we did not use these variables) | |
Blood pressure | Average of two measurements of systolic blood pressure (SBP) and diastolic blood pressure (DBP) | |
Known hypertension (self-report) | Y if ever told you had high blood pressure, or taking prescription (or treatment) for hypertension | |
Hypertension/prehypertension | Hypertension if SBP ≥140 mm Hg or DBP ≥90 mm Hg | |
Prehypertension if no hypertension and (120≤ SBP <140 or 80≤ DBP <90) | ||
Family history of DM | Y if parent or sibling had DM | |
Total DM | Y if known DM (see above) or based on lab test (see below) | |
Physically active | Y if days of any of the following activities are more than 5 day/wk: vigorous or moderate recreational activities; moderate work; or walk or bicycle | Y if exercise to control or lose weight, or exercise ≥60 min/day for 4 or more day/wk |
Gestational diabetes | Y if you are woman and told you have diabetes during pregnancy | Not measured |
Current smoker | Y if average number of cigarettes/day during past 30 days is >1; smoke cigarettes every day or some days; or used any tobacco product last 5 days | Y if smoke cigarettes every day or some days |
Alcohol, light or moderate/heavy | Moderate/heavy drinker if average number of alcoholic drinks/day for past 12 mo is ≥5; >60 days drink alcohol over past 12 mo; 4/5 drinks >60 days or ever every day | Moderate/heavy drinker if ≥5 glasses on ≥2 day/wk |
Light drinker if not moderate/heavy drinker, and average number of alcoholic drinks/day for past 12 mo is 1–4 (note: in 2017–2018, 60 day/yr was replaced by 2 time/wk because day/yr was not assessed) | Light drinker if not moderate/heavy drinker, and drink at least once a mo | |
Anemia | Y if taking anemia treatment past 3 mo, or hemoglobin <10 g/dL | Y if hemoglobin <10 g/dL |
Cardiovascular disease | Y if ever told had coronary heart disease, heart attack, or stroke | |
(Congestive) heart failure | Y if ever told had congestive heart failure | Not measured |
Proteinuria | Y if albumin-creatinine ratio ≥30 mg/g | Y if non-negative result from urine protein test |
DM/pre-DM (based on lab tests) | DM if (8 hours) fasting glucose ≥126 mg/dL; non-fasting glucose ≥200 mg/dL; HbA1c ≥6.5%; or 2-hr glucose ≥200 mg/dL | Same as NHANES except that 2-hr glucose was not measured |
Pre-DM if no DM, and fasting glucose in 100–125; HbA1c in 5.7%–6.4%; or 2-hr glucose in 140–199 (note: 2-hr glucose was not available for 2017–2018) | ||
CKD | Y if eGFR <60 mL/min/1.73 m2, where eGFR was derived from the CKD-EPI formula, which is a function of serum creatinine, age, sex, and race (note: MDRD formula was used in sensitivity analysis. Also, in the KDIGO 2012 Guideline, CKD is defined as abnormalities of kidney structure or function present for >3 mo, as manifested by markers of kidney damage [including albuminuria] or decreased GFR. In the present study, CKD was defined only by decreased GFR but proteinuria was ignored. Thus, the incidence of CKD could have been underestimated considerably depending on the definition used). | Same as NHANES; non-Black formula was used (note: Korean CKD-EPI formula was used in sensitivity analysis) |
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. 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), 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), Due to different assessments, % may not be comparable in the two countries, Left/right values are when USA/Korean Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formulas were used. See
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. NHANES 2015–2018 and KNHANES 2016–2018 among adults (≥19 year old) were used. For DM, known DM were excluded. Prediction equations are in Empty cells are due to different questions included in different questionnaires.
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). 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 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; Is due to multicollinearity; DM showed unadjusted OR, 2.95 (95% CI, 2.50 to 3.48; Empty cells are due to different questions included in different questionnaires.
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. 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, 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.