J Clin Med Res

Journal of Clinical Medicine Research, ISSN 1918-3003 print, 1918-3011 online, Open Access

Article copyright, the authors; Journal compilation copyright, J Clin Med Res and Elmer Press Inc

Journal website https://jocmr.elmerjournals.com

Original Article

Volume 16, Number 12, December 2024, pages 589-599

Association Between Chronic Kidney Disease Risk Categories and Abdominal Aortic Calcification: Insights From the National Health and Nutrition Examination Survey

Figure 1. Flowchart of selection of participants. AAC: abdominal aortic calcification; NHANES: National Health and Nutrition Examination Survey.

**Table 1.** Demographics and Laboratory Findings of Included Patients
Variables	Severe AAC, n = 423, Population size (weighted estimate = 14,592,085)	No severe AAC, n = 2,717, Population size (weighted estimate = 112,592,130)	P-value
AAC: abdominal aortic calcification; Apo B: apolipoprotein B; CI: confidence interval; eGFR: estimated glomerular filtration rate; Hb: hemoglobin; HDL: high-density lipoprotein; LDL: low-density lipoprotein; OR: odds ratio; SE: standard error.
Age (years)	69.2	1.0	55.9	0.5	< 0.001
Body mass index (kg/m²)	27.2	0.8	28.7	0.2	0.09
Urine albumin/creatinine ratio (mg/g)	102.3	16.7	35.0	10.7	0.19
Albumin (g/dL)	4.2	0.03	4.2	0.02	0.61
Creatinine (mg/dL)	1.1	0.02	0.9	0.02	0.27
Uric acid (mg/dL)	5.7	0.2	5.4	0.04	0.082
Sodium (mmol/L)	140.2	0.2	139.9	0.1	0.19
Potassium (mmol/L)	4.2	0.04	4.1	0.02	0.054
Bicarbonate (mmol/L)	25.9	0.2	25.5	0.2	0.076
Blood urea nitrogen (mg/dL)	16.5	0.8	13.6	0.2	0.001
Chloride (mmol/L)	103.6	0.2	104.3	0.1	0.013
Calcium (mg/dL)	9.5	0.03	9.4	0.02	0.072
eGFR (mL/min/1.73 m²)	70.0	1.7	86.2	0.7	0.00001
Phosphorus (mg/dL)	3.8	0.05	3.7	0.02	0.04
Klotho (pg/mL)	799.9	22.3	842.0	13.3	0.1
Lymphocyte (1,000 cells/µL)	1.8	0.1	1.9	0.03	0.14
Segmented neutrophils (1,000 cells/µL)	4.1	0.1	4.1	0.1	0.34
Hemoglobin (g/dL)	14.1	0.2	14.3	0.1	0.18
Platelet count (1,000 cells/µL)	217.2	4.1	231.5	1.6	0.002
Platelet/lymphocyte ratio	137.0	6.3	131.1	1.3	0.23
Neutrophil/lymphocyte ratio	2.7	0.1	2.3	0.04	0.00001
Triglycerides (mg/dL)	140.8	7.6	135.7	4.9	0.5
LDL-cholesterol (mg/dL)	109.4	4.1	116.3	1.1	0.2
HDL-cholesterol (mg/dL)	55.3	1.8	55.3	0.5	0.98
Insulin (µIU/mL)	12.7	1.2	12.3	0.76	0.62
HbA1c (%)	6.1	0.1	5.7	0.027	0.034
Apo B (mg/dL)	92	2.59	94	2.7	0.44

Table 1. Demographics and Laboratory Findings of Included Patients

Variables

Severe AAC, n = 423, Population size (weighted estimate = 14,592,085)

No severe AAC, n = 2,717, Population size (weighted estimate = 112,592,130)

P-value

Mean

AAC: abdominal aortic calcification; Apo B: apolipoprotein B; CI: confidence interval; eGFR: estimated glomerular filtration rate; Hb: hemoglobin; HDL: high-density lipoprotein; LDL: low-density lipoprotein; OR: odds ratio; SE: standard error.

Age (years)

69.2

1.0

55.9

0.5

< 0.001

Body mass index (kg/m²)

27.2

0.8

28.7

0.2

0.09

Urine albumin/creatinine ratio (mg/g)

102.3

16.7

35.0

10.7

0.19

Albumin (g/dL)

4.2

0.03

4.2

0.02

0.61

Creatinine (mg/dL)

1.1

0.02

0.9

0.02

0.27

Uric acid (mg/dL)

5.7

0.2

5.4

0.04

0.082

Sodium (mmol/L)

140.2

0.2

139.9

0.1

0.19

Potassium (mmol/L)

4.2

0.04

4.1

0.02

0.054

Bicarbonate (mmol/L)

25.9

0.2

25.5

0.2

0.076

Blood urea nitrogen (mg/dL)

16.5

0.8

13.6

0.2

0.001

Chloride (mmol/L)

103.6

0.2

104.3

0.1

0.013

Calcium (mg/dL)

9.5

0.03

9.4

0.02

0.072

eGFR (mL/min/1.73 m²)

70.0

1.7

86.2

0.7

0.00001

Phosphorus (mg/dL)

3.8

0.05

3.7

0.02

0.04

Klotho (pg/mL)

799.9

22.3

842.0

13.3

0.1

Lymphocyte (1,000 cells/µL)

1.8

0.1

1.9

0.03

0.14

Segmented neutrophils (1,000 cells/µL)

4.1

0.1

4.1

0.1

0.34

Hemoglobin (g/dL)

14.1

0.2

14.3

0.1

0.18

Platelet count (1,000 cells/µL)

217.2

4.1

231.5

1.6

0.002

Platelet/lymphocyte ratio

137.0

6.3

131.1

1.3

0.23

Neutrophil/lymphocyte ratio

2.7

0.1

2.3

0.04

0.00001

Triglycerides (mg/dL)

140.8

7.6

135.7

4.9

0.5

LDL-cholesterol (mg/dL)

109.4

4.1

116.3

1.1

0.2

HDL-cholesterol (mg/dL)

55.3

1.8

55.3

0.5

0.98

Insulin (µIU/mL)

12.7

1.2

12.3

0.76

0.62

HbA1c (%)

6.1

0.1

5.7

0.027

0.034

Apo B (mg/dL)

2.59

2.7

0.44

**Table 2.** Univariate Analysis
Variables	No AAC unweighted (n = 2,717)	No AAC weighted (n = 1.108 × 10⁸), SE 7.107 × 10⁶*	AAC unweighted (n = 423)	AAC weighted (1.490 × 10⁷) SE 1.154 × 10⁶*	OR	95% CI	P-value
*Univariate analysis of demographic and clinical variables by the presence of severe abdominal aortic calcification. AAC: abdominal aortic calcification; CI: confidence interval; OR: odds ratio; SE: standard error.
Sex (male)	1,314 (48%)	5.37 × 10⁷ (48%)	204 (48%)	6.76 × 10⁶ (45%)	0.89	0.6 - 1.30	0.49
Race (Caucasian)	1,129 (42%)	7.78 × 10⁷ (70%)	246 (58%)	1.15 × 10⁷ (77%)	1.43	0.96 - 2.14	0.07
Hypertension	1,460 (53%)	5.56 × 10⁷ (50%)	335 (79%)	1.18 × 10⁷ (79%)	3.77	2.8 - 5.10	0.00001
Diabetes	543 (20%)	1.70 × 10⁷ (15%	151 (36%)	4.70 × 10⁶ (31%)	2.53	1.93 - 3.30	0.00001
Hypercholesterolemia	1,275 (47%)	5.34 × 10⁷ (48%)	273 (61%)	9.73 × 10⁶ (65%)	2.03	1.57 - 2.61	0.00002
Smoked more than 100 cigarettes in a lifetime	1,207 (44%)	4.91 × 10⁷ (44%)	254 (57%)	8.7 × 10⁶ (58%)	1.75	1.30 - 2.40	0.0015

Table 2. Univariate Analysis

Variables

No AAC unweighted (n = 2,717)

No AAC weighted (n = 1.108 × 10⁸), SE 7.107 × 10⁶*

AAC unweighted (n = 423)

AAC weighted (1.490 × 10⁷) SE 1.154 × 10⁶*

95% CI

P-value

*Univariate analysis of demographic and clinical variables by the presence of severe abdominal aortic calcification. AAC: abdominal aortic calcification; CI: confidence interval; OR: odds ratio; SE: standard error.

Sex (male)

1,314 (48%)

5.37 × 10⁷ (48%)

204 (48%)

6.76 × 10⁶ (45%)

0.89

0.6 - 1.30

0.49

Race (Caucasian)

1,129 (42%)

7.78 × 10⁷ (70%)

246 (58%)

1.15 × 10⁷ (77%)

1.43

0.96 - 2.14

0.07

Hypertension

1,460 (53%)

5.56 × 10⁷ (50%)

335 (79%)

1.18 × 10⁷ (79%)

3.77

2.8 - 5.10

0.00001

Diabetes

543 (20%)

1.70 × 10⁷ (15%

151 (36%)

4.70 × 10⁶ (31%)

2.53

1.93 - 3.30

0.00001

Hypercholesterolemia

1,275 (47%)

5.34 × 10⁷ (48%)

273 (61%)

9.73 × 10⁶ (65%)

2.03

1.57 - 2.61

0.00002

Smoked more than 100 cigarettes in a lifetime

1,207 (44%)

4.91 × 10⁷ (44%)

254 (57%)

8.7 × 10⁶ (58%)

1.75

1.30 - 2.40

0.0015

**Table 3.** Multivariable Logistic Regression of Risk Factors for Severe AAC
Variables	OR	SE	95% CI	P-value
AAC: abdominal aortic calcification; CI: confidence interval; eGFR: estimated glomerular filtration rate; OR: odds ratio; Ref: reference; SE: standard error.
Age	1.10	0.01	1.05	1.11	0.00001
History of hypertension	1.83	0.48	1.04	3.21	0.03
Smoking history	1.76	0.45	1.03	3.0	0.04
eGFR	0.98	0.01	0.97	0.98	0.004

Table 3. Multivariable Logistic Regression of Risk Factors for Severe AAC

Variables

95% CI

P-value

AAC: abdominal aortic calcification; CI: confidence interval; eGFR: estimated glomerular filtration rate; OR: odds ratio; Ref: reference; SE: standard error.

Age

1.10

0.01

1.05

1.11

0.00001

History of hypertension

1.83

0.48

1.04

3.21

0.03

Smoking history

1.76

0.45

1.03

3.0

0.04

eGFR

0.98

0.01

0.97

0.98

0.004

**Table 4.** Multivariate Analysis of Renal Risk for CKD and AAC
Renal risk category	OR	SE	95% CI	P-value
AAC: abdominal aortic calcification; BMI: body mass index; CI: confidence interval; CKD: chronic kidney disease; OR: odds ratio; Ref: reference; SE: standard error.
Multivariable logistic regression analysis of renal risk for CKD and AAC (unadjusted model)
1	Ref.	Ref.	Ref.	Ref.	Ref.
2	3.93	0.96	2.34	6.60	< 0.001
3	3.75	1.74	1.40	10.08	0.012
4	10.48	5.95	3.13	35.14	0.001
Multivariable logistic regression analysis of renal risk and AAC adjusted for age
1	Ref.	Ref.	Ref.	Ref.	Ref.
2	1.80	0.48	1.02	3.16	0.043
3	1.34	0.64	0.48	3.72	0.549
4	6.34	6.09	0.82	49.05	0.073
Multivariable logistic regression analysis of renal risk and AAC adjusted for age and hypertension
1	Ref.	Ref.	Ref.	Ref.	Ref.
2	1.60	0.43	0.96	2.94	0.067
3	1.30	0.60	0.48	3.46	0.59
4	5.30	4.8	0.76	36	0.09
Multivariable logistic regression analysis of renal risk and AAC adjusted for age, hypertension, and smoking history
1	Ref.	Ref.	Ref.	Ref.	Ref.
2	1.72	0.43	0.9	2.86	0.06
3	1.07	0.50	0.40	3.0	0.90
4	5.7	5.0	0.85	38	0.070
Multivariable logistic regression analysis of renal risk and AAC adjusted for age, hypertension, smoking history and BMI
1	Ref	Ref	Ref	Ref	Ref
2	1.73	0.44	1.00	2.98	0.05
3	1.18	0.51	0.47	2.95	0.70
4	6.34	6.13	0.80	49.83	0.08

Table 4. Multivariate Analysis of Renal Risk for CKD and AAC

Renal risk category

95% CI

P-value

AAC: abdominal aortic calcification; BMI: body mass index; CI: confidence interval; CKD: chronic kidney disease; OR: odds ratio; Ref: reference; SE: standard error.

Multivariable logistic regression analysis of renal risk for CKD and AAC (unadjusted model)

Ref.

3.93

0.96

2.34

6.60

< 0.001

3.75

1.74

1.40

10.08

0.012

10.48

5.95

3.13

35.14

0.001

Multivariable logistic regression analysis of renal risk and AAC adjusted for age

Ref.

1.80

0.48

1.02

3.16

0.043

1.34

0.64

0.48

3.72

0.549

6.34

6.09

0.82

49.05

0.073

Multivariable logistic regression analysis of renal risk and AAC adjusted for age and hypertension

Ref.

1.60

0.43

0.96

2.94

0.067

1.30

0.60

0.48

3.46

0.59

5.30

4.8

0.76

0.09

Multivariable logistic regression analysis of renal risk and AAC adjusted for age, hypertension, and smoking history

Ref.

1.72

0.43

0.9

2.86

0.06

1.07

0.50

0.40

3.0

0.90

5.7

5.0

0.85

0.070

Multivariable logistic regression analysis of renal risk and AAC adjusted for age, hypertension, smoking history and BMI

Ref

1.73

0.44

1.00

2.98

0.05

1.18

0.51

0.47

2.95

0.70

6.34

6.13

0.80

49.83

0.08

**Table 5.** Subgroup Analyses Based on Patients’ Demographics and Comorbidities and Renal Risk Categories
Variables	Renal risk category	OR	95% CI	P-value	P-value for interaction
^aThere were no participants with no history of hypertension in renal risk category for AAC class 4. CI: confidence interval; OR: odds ratio; Ref: reference.
Age < 65	1	Ref.	Ref.	Ref.	Ref.	0.453
	2	2.27	0.73	7.05	0.144
	3	4.02	0.68	23.74	0.116
	4	14.54	2.99	70.68	0.003
Age ≥ 65	1	Ref.	Ref.	Ref.	Ref.
	2	2.29	1.20	4.357	0.015
	3	1.51	0.52	4.41	0.421
	4	4.41	1.15	16.89	0.033
Male gender	1	Ref.	Ref.	Ref.	Ref.	0.714
	2	4.85	2.66	8.83	0.0001
	3	5.42	1.37	21.51	0.019
	4	7.99	1.31	48.64	0.027
Female gender	1	Ref.	Ref.	Ref.	Ref.
	2	3.32	1.67	6.57	0.002
	3	1.66	0.17	16.59	0.648
	4	39.92	3.20	498.00	0.007
History of diabetes mellitus	1	Ref.	Ref.	Ref.	Ref.	0.288
	2	1.89	0.88	4.09	0.098
	3	2.94	0.73	11.85	0.121
	4	5.49	1.16	25.87	0.033
No history of diabetes mellitus	1	Ref.	Ref.	Ref.	Ref.
	2	4.71	2.54	8.74	0.0001
	3	1.89	0.30	8.96	0.398
	4	9.82	0.76	127.79	0.077
White race	1	Ref.	Ref.	Ref.	Ref.	0.818
	2	3.93	1.81	8.51	0.002
	3	4.57	1.31	15.93	0.02
	4	11.00	1.50	80.66	0.022
Non-white race	1	Ref.	Ref.	Ref.	Ref.
	2	2.27	0.73	7.05	0.144
	3	4.02	0.68	23.74	0.116
	4	14.53	2.99	70.68	0.003
History of hypertension	1	Ref.	Ref.	Ref.	Ref.	0.411
	2	3.01	1.81	5.02	0.0001
	3	2.32	0.79	6.83	0.117
	4	6.82	1.90	24.47	0.006
No history of hypertension	1	Ref.	Ref.	Ref.	Ref.
	2	3.59	1.35	9.54	0.014
	3	7.58	0.66	87.09	0.097
	4^a	n/a	n/a	n/a	n/a

Table 5. Subgroup Analyses Based on Patients’ Demographics and Comorbidities and Renal Risk Categories

Variables

Renal risk category

95% CI

P-value

P-value for interaction

^aThere were no participants with no history of hypertension in renal risk category for AAC class 4. CI: confidence interval; OR: odds ratio; Ref: reference.

Age < 65

Ref.

0.453

2.27

0.73

7.05

0.144

4.02

0.68

23.74

0.116

14.54

2.99

70.68

0.003

Age ≥ 65

Ref.

2.29

1.20

4.357

0.015

1.51

0.52

4.41

0.421

4.41

1.15

16.89

0.033

Male gender

Ref.

0.714

4.85

2.66

8.83

0.0001

5.42

1.37

21.51

0.019

7.99

1.31

48.64

0.027

Female gender

Ref.

3.32

1.67

6.57

0.002

1.66

0.17

16.59

0.648

39.92

3.20

498.00

0.007

History of diabetes mellitus

Ref.

0.288

1.89

0.88

4.09

0.098

2.94

0.73

11.85

0.121

5.49

1.16

25.87

0.033

No history of diabetes mellitus

Ref.

4.71

2.54

8.74

0.0001

1.89

0.30

8.96

0.398

9.82

0.76

127.79

0.077

White race

Ref.

0.818

3.93

1.81

8.51

0.002

4.57

1.31

15.93

0.02

11.00

1.50

80.66

0.022

Non-white race

Ref.

2.27

0.73

7.05

0.144

4.02

0.68

23.74

0.116

14.53

2.99

70.68

0.003

History of hypertension

Ref.

0.411

3.01

1.81

5.02

0.0001

2.32

0.79

6.83

0.117

6.82

1.90

24.47

0.006

No history of hypertension

Ref.

3.59

1.35

9.54

0.014

7.58

0.66

87.09

0.097

4^a

n/a