General characteristics of study participants
Baseline characteristics of participants according to hyperuricemia status are shown in Table 1. 18.38% of 20081 study participants had hyperuricemia. In general, participants with hyperuricemia were more likely to be older, male, Non-Hispanic black, had higher levels of obesity (BMI, WC, VAI and LAP), creatinine and lower levels of physical activity, as compared with those without hyperuricemia. In addition, a higher proportion of those classified as hyperuricemia smoked more, and a higher proportion of them suffered from other diseases.
Table 1. Baseline characteristics of participants according to Hyperuricemia status
Characteristics
|
All participants (n=20081)
|
|
Hyperuricemia
|
P value
|
Yes (N = 3691)
|
|
No (N=16390)
|
Mean, n
|
SD, %
|
|
Mean, n
|
SD, %
|
|
Mean, n
|
SD, %
|
Age group, n (%)
|
|
|
|
|
|
|
|
|
<0.001
|
20~39
|
6396
|
31.8
|
|
889
|
24.1
|
|
5507
|
33.6
|
|
40~59
|
6885
|
34.3
|
|
1099
|
29.8
|
|
5786
|
35.3
|
|
60~
|
6800
|
33.9
|
|
1703
|
46.1
|
|
5097
|
31.1
|
|
Gender, n (%)
|
|
|
|
|
|
|
|
|
<0.001
|
Male
|
9537
|
47.5
|
|
1965
|
53.2
|
|
7572
|
46.2
|
|
Female
|
10544
|
52.5
|
|
1726
|
46.8
|
|
8818
|
53.8
|
|
Race, n(%)
|
|
|
|
|
|
|
|
|
<0.001
|
Hispanic
|
5186
|
25.8
|
|
681
|
18.5
|
|
4505
|
27.5
|
|
Non-Hispanic white
|
3993
|
19.9
|
|
906
|
24.5
|
|
3087
|
18.8
|
|
Non-Hispanic black
|
8940
|
44.5
|
|
1762
|
47.7
|
|
7178
|
43.8
|
|
others
|
1962
|
9.8
|
|
342
|
9.3
|
|
1620
|
9.9
|
|
Poverty index, n(%)
|
|
|
|
|
|
|
|
|
0.001
|
<1.3
|
6336
|
31.6
|
|
1179
|
31.9
|
|
5157
|
31.5
|
|
1.3~3.5
|
7504
|
37.4
|
|
1454
|
39.4
|
|
6050
|
36.9
|
|
>=3.5
|
6241
|
31.1
|
|
1058
|
28.7
|
|
5183
|
31.6
|
|
Continued table 1. Baseline characteristics of participants according to Hyperuricemia status
|
Characteristics
|
All participants (n=20081)
|
|
Hyperuricemia
|
P value
|
Yes (N = 3691)
|
|
No (N=16390)
|
Mean, n
|
SD, %
|
|
Mean, n
|
SD, %
|
|
Mean, n
|
SD, %
|
Vigorous recreational activities, n(%)
|
|
|
|
|
|
|
|
|
<0.001
|
Yes
|
4435
|
22.1
|
|
610
|
16.5
|
|
3825
|
23.3
|
|
No
|
15646
|
77.9
|
|
3081
|
83.5
|
|
12565
|
76.7
|
|
Smoking at least 100 cigarettes in life, n(%)
|
|
|
|
|
|
|
|
|
<0.001
|
Yes
|
8840
|
44.0
|
|
1774
|
48.1
|
|
7066
|
43.1
|
|
No
|
11241
|
56.0
|
|
1917
|
51.9
|
|
9324
|
56.9
|
|
Hypertension, n(%)
|
|
|
|
|
|
|
|
|
<0.001
|
Yes
|
7491
|
37.3
|
|
1586
|
43.0
|
|
5386
|
32.9
|
|
No
|
12590
|
63.7
|
|
2105
|
57.0
|
|
11004
|
67.1
|
|
Diabetes, n (%)
|
|
|
|
|
|
|
|
|
<0.001
|
Yes
|
2531
|
12.6
|
|
678
|
18.4
|
|
1853
|
11.3
|
|
No
|
17550
|
87.4
|
|
3013
|
81.6
|
|
14537
|
88.7
|
|
Drinking, n(%)
|
|
|
|
|
|
|
|
|
0.932
|
Yes
|
5637
|
28.1
|
|
1034
|
28
|
|
4603
|
28.1
|
|
No
|
14444
|
71.9
|
|
2657
|
72
|
|
11787
|
71.9
|
|
|
|
|
|
|
|
|
|
|
|
Continue table 1. Baseline characteristics of participants according to Hyperuricemia status
|
Characteristics
|
All participants (n=20081)
|
|
Hyperuricemia
|
P value
|
Yes (N = 3691)
|
|
No (N=16390)
|
Mean, n
|
SD, %
|
|
Mean, n
|
SD, %
|
|
Mean, n
|
SD, %
|
CVD, n(%)
|
|
|
|
|
|
|
|
|
<0.001
|
Yes
|
2098
|
10.4
|
|
661
|
17.9
|
|
1437
|
8.8
|
|
No
|
17983
|
89.6
|
|
3030
|
82.1
|
|
14953
|
91.2
|
|
Liver disease, n (%)
|
|
|
|
|
|
|
|
|
<0.001
|
Yes
|
768
|
3.8
|
|
186
|
5.0
|
|
582
|
3.6
|
|
No
|
19313
|
96.2
|
|
3505
|
95.0
|
|
15808
|
96.4
|
|
Dyslipidemia, n(%)
|
|
|
|
|
|
|
|
|
<0.001
|
Yes
|
7595
|
37.8
|
|
1848
|
50.1
|
|
5747
|
35.1
|
|
No
|
12486
|
62.2
|
|
1843
|
49.9
|
|
10643
|
64.9
|
|
WC, mean (SD)
|
99.64
|
16.25
|
|
108.42
|
16.37
|
|
97.66
|
15.56
|
<0.001
|
BMI, mean (SD)
|
29.20
|
6.75
|
|
32.46
|
7.41
|
|
28.47
|
6.37
|
<0.001
|
VAI, mean (SD)
|
2.61
|
3.45
|
|
3.23
|
3.39
|
|
2.47
|
3.45
|
<0.001
|
LAP, mean (SD)
|
71.51
|
78.30
|
|
97.37
|
78.31
|
|
65.69
|
77.11
|
<0.001
|
Energery, mean (SD)
|
1971.06
|
695.81
|
|
1924.74
|
703.04
|
|
1981.49
|
693.76
|
<0.001
|
creatinine,mean (SD)
|
0.89
|
0.42
|
|
1.05
|
0.46
|
|
0.86
|
0.41
|
<0.001
|
Continuous variables are expressed as mean and standard deviation (SD), categorical variables presented are as counts and percentage.
a WC means waist circumference.
b BMI means body mass index.
b VAI means Visceral adiposity index.
d LAP means Lipid accumulation product Index.
In addition, in terms of demographics and health-related factors, there were no significant differences between the analytical sample and full NHANES (2007-2016) sample (Supplemental Table S1).
Nutrient patterns
Principal component analysis
We derived 3 independent nutrient patterns based on principal component analysis of complex survey, which explained 71.6% of the total variance.
The first pattern was negatively correlated with protein, fat, carbohydrate, cholesterol, choline, sodium and selenium, termed as “Low energy diet”; Pattern 2 was negatively correlated with vitamin A, vitamin C, vitamin K, carotene, lutein, termed as “Lower vitamin A, C, K pattern”; Pattern 3 was positively correlated with vitamin B6, B12, folate, and termed as “Vitamin B group”. The factor loadings for each nutrient pattern were shown in Supplemental Table S2.
Reduced rank regression
Only the first nutrient pattern was kept for further analyses based on RRR, since it explained the biggest variance (20.01%) of the response variables. It was positively correlated with fat, cholesterol and negatively associated with Vitamin A, C, D, K, fiber, folate, and termed as “High fat and low vitamin diet”. The factor loadings of the pattern and the correlation coefficients with the response variables were shown in Supplemental Table S3.
Nutrient patterns and the risk of hyperuricemia and obesity
Multivariate logistic regression analyses in the associations between 4 nutrient patterns with hyperuricemia are shown in Table 2. After adjusting for all confounders (Model 3), there are two patterns that are significantly related to hyperuricemia. Among them, the “Vitamin B group” was based on principal component analysis, compared to the first quartile as reference, the higher ORs were 0.81(0.67,0.99), 0.75(0.63,0.89) and 0.63(0.51,0.77) respectively. In addition, “High fat and low vitamin diet” based on RRR was significantly related to hyperuricemia, compared with the lowest quartile, the adjusted OR indicated a dose-dependent relation with each quartile increment (P for trend <0.001). The OR in the highest quartile was 1.23 (1.06, 1.41).
Table 2. Odds ratios and 95% confidence intervals for the association between nutrient patterns and hyperuricemia
Nutrient patterns
|
Quartiles of nutrient pattern scores
|
P-trend
|
Q1
|
Q2
|
Q3
|
Q4
|
OR (95% CI)
|
OR (95% CI)
|
OR (95% CI)
|
PCAa
|
|
|
|
|
|
Lower energy diet
|
|
|
|
|
|
Model 1 c
|
Ref.
|
0.79 (0.67, 0.94)
|
0.88 (0.76, 1.02)
|
0.88 (0.74, 1.05)
|
0.296
|
Model 2 d
|
Ref.
|
0.85 (0.70, 1.02)
|
1.01 (0.85, 1.20)
|
1.04 (0.88 ,1.24)
|
0.267
|
Model 3 e
|
Ref.
|
0.84 (0.68, 1.03)
|
1.01 (0.78, 1.29)
|
1.00 (0.73, 1.37)
|
0.459
|
Low vitamin A, C, K pattern
|
|
|
|
|
|
Model 1 c
|
Ref.
|
1.07 (0.89, 1.29)
|
1.20 (1.01, 1.42)
|
1.25 (1.03, 1.52)
|
0.009
|
Model 2 d
|
Ref.
|
1.04 (0.87, 1.25)
|
1.16 (0.97, 1.39)
|
1.22 (0.98, 1.52)
|
0.036
|
Model 3 e
|
Ref.
|
1.01 (0.84, 1.22)
|
1.12 (0.93, 1.34)
|
1.17 (0.93, 1.46)
|
0.104
|
Vitamin B group
|
|
|
|
|
|
Model 1 c
|
Ref.
|
0.84 (0.70, 1.02)
|
0.74 (0.62, 0.89)
|
0.63 (0.51, 0.77)
|
<0.001
|
Model 2 d
|
Ref.
|
0.82 (0.67, 0.99)
|
0.74 (0.62, 0.88)
|
0.63 (0.51, 0.77)
|
<0.001
|
Model 3 e
|
Ref.
|
0.81 (0.67, 0.99)
|
0.75 (0.63, 0.89)
|
0.63 (0.51, 0.77)
|
<0.001
|
RRRb
|
|
|
|
|
|
High fat and low vitamin diet
|
|
|
|
|
|
Model 1 c
|
Ref.
|
1.09 (0.92, 1.29)
|
1.27 (1.10, 1.46)
|
1.37 (1.18, 1.58)
|
<0.001
|
Model 2 d
|
Ref.
|
1.11 (0.93, 1.32)
|
1.27 (1.09, 1.48)
|
1.32 (1.14, 1.52)
|
<0.001
|
Model 3 e
|
Ref.
|
1.00 (0.84, 1.19)
|
1.14 (0.97, 1.32)
|
1.23 (1.06, 1.41)
|
<0.001
|
a PCA is the method of principal component analysis and including “Lower energy diet”, “Low vitamin A, C, K pattern” and “Vitamin B group” 3 nutrient patterns.
b RRR stands for Reduced Rank Regression and including “High fat and low vitamin diet” pattern which is related to obesity.
c Model 1 was a crude model;
d Model 2 was adjusted for age, race, gender;
e Model 3 was further adjusted for adjusted for smoking, drinking, vigorous physical activity, pox ratio, creatinine level, energy intake, the history of diabetes, hypertension, cardiovascular diseases, cancer, liver disease and dyslipidemia.
The results of multivariable linear regression analysis were shown inTable 3. All four nutrient patterns were correlated with BMI, WC and LAP (P for trend <0.05). Further, VAI was also significantly correlated with “High fat and low vitamin diet”.
Table3. The association between nutrient patterns and obesity indicators
Nutrient patterns
|
Quartiles of nutrient pattern scores
|
P-trend
|
Q1
|
Q2 (95% CI)
|
Q3 (95% CI)
|
Q4 (95% CI)
|
PCAa
|
|
|
|
|
|
Lower energy diet
|
|
|
|
|
|
BMI
|
0
|
-1.37 (-1.89,-0.84)
|
-1.93 (-2.59,-1.26)
|
-2.67 (-3.49,-1.85)
|
<0.001
|
WC
|
0
|
-2.87 (-4.12,-1.63)
|
-4.51 (-5.99,-3.02)
|
-6.06 (-7.90,-4.23)
|
<0.001
|
VAI
|
0
|
-0.22 (-0.41,-0.02)
|
-0.19 (-0.48,0.09)
|
-0.28 (-0.59,0.04)
|
0.211
|
LAP
|
0
|
-8.89 (-14.15,-3.63)
|
-11.02 (-18.38,-3.65)
|
-15.32 (-24.25,-6.38)
|
0.003
|
Low vitamin A, C, K pattern
|
|
|
|
|
|
BMI
|
0
|
0.29 (-0.08,0.66)
|
0.92 (0.55,1.28)
|
1.02 (0.61,1.42)
|
<0.001
|
WC
|
0
|
0.95 (0.10,1.80)
|
2.23 (1.38,3.07)
|
2.77 (1.85,3.70)
|
<0.001
|
VAI
|
0
|
-0.11 (-0.27,0.05)
|
-0.03 (-0.19,0.13)
|
0.11 (-0.10,0.31)
|
0.263
|
LAP
|
0
|
-0.74 (-4.35,2.87)
|
2.42 (-1.13,5.97)
|
3.70 (-0.48,7.88)
|
0.037
|
Vitamin B group
|
|
|
|
|
|
BMI
|
0
|
-0.39 (-0.86,0.07)
|
-0.95 (-1.4,-0.51)
|
-1.48 (-1.92,-1.05)
|
<0.001
|
WC
|
0
|
-1.22 (-2.31,-0.14)
|
-2.35 (-3.39,-1.31)
|
-3.61 (-4.59,-2.63)
|
<0.001
|
VAI
|
0
|
0.04 (-0.12,0.19)
|
-0.07 (-0.21,0.08)
|
-0.10 (-0.25,0.05)
|
0.075
|
LAP
|
0
|
-0.89 (-4.36,2.58)
|
-4.05 (-7.9,-0.19)
|
-6.47 (-9.9,-3.04)
|
<0.001
|
RRRb
|
|
|
|
|
|
High fat and low vitamin diet
|
|
|
|
|
|
BMI
|
0
|
0.91 (0.59, 1.24)
|
1.78 (1.41, 2.15)
|
2.73 (2.35, 3.11)
|
<0.001
|
WC
|
0
|
2.44 (1.66, 3.23)
|
4.57 (3.68, 5.46)
|
6.89 (6.02, 7.77)
|
<0.001
|
VAI
|
0
|
0.24 (0.07, 0.41)
|
0.28 (0.09, 0.47)
|
0.24 (0.07, 0.40)
|
0.005
|
LAP
|
0
|
7.87 (3.92, 11.83)
|
9.94 (5.51, 14.37)
|
13.61 (9.54, 17.68)
|
<0.001
|
Survey linear regression models were used to estimate β and 95% CIs and adjusted for smoking, drinking, vigorous physical activity, pox ratio, creatinine level, energy intake, the history of diabetes, hypertension, cardiovascular diseases, cancer, liver disease and dyslipidemia.
a PCA is the method of principal component analysis and including “Lower energy diet”, “Low vitamin A, C, K pattern” and “Vitamin B group” 3 nutrient patterns.
b RRR stands for Reduced Rank Regression and including “High fat and low vitamin diet” pattern which is related to obesity.
Mediating role of obesity indicators in the association between nutrient patterns and hyperuricemia
Table 4 presents the direct and indirect effect of nutrient patterns on hyperuricemia with obesity measures as mediators. Overall, all four obesity indicators mediated the relationship between each nutrient pattern and hyperuricemia more or less. Further, the direct effects of the other three nutrient patterns in relation to hyperuricemia were almost insignificant except for the Vitamin B group. Conclusions suggest that the association of each nutrient pattern with hyperuricemia was mediated by obesity. Although the indirect and direct effects were in opposite directions for two nutrient patterns and the proportion of indirect effects in this case could not be explained, we found obesity measures (BMI, WC, LAP) fully mediated the relationship between “High fat and low vitamin pattern” based on RRR and hyperuricemia. In particular, two common obesity measures (BMI, WC) had significant mediating effects on the relationships between all four nutrient patterns and hyperuricemia and the mediating proportion were as high as 53.34 and 59.69, respectively. In addition, LAP also mediated the relationship between the three nutrient patterns and hyperuricemia, although the indirect effect was not as large as that of BMI and WC.
Table4. Mediating effects of obesity on the association between nutrient patterns and odds ratios of hyperuricemia
Nutrient patterns
|
Direct effects
|
Indirect effects
|
Proportion of indirect effect
|
OR (95% CI)
|
OR (95% CI)
|
PCAa
|
|
|
|
Lower energy diet
|
|
|
|
BMI
|
1.14 (1.00, 1.28)
|
0.94 (0.92, 0.95)
|
NAc
|
WC
|
1.13 (0.99, 1.28)
|
0.94 (0.92, 0.95)
|
NAc
|
LAP
|
1.06 (0.94, 1.21)
|
0.98 (0.97, 1.00)
|
NAc
|
VAI
|
1.05 (0.93, 1.08)
|
1.00 (0.99, 1.01)
|
0.12%
|
Low vitamin A, C, K pattern
|
|
|
|
BMI
|
1.03 (0.96, 1.11)
|
1.03 (1.02, 1.04)
|
53.34%
|
WC
|
1.03 (0.96, 1.10)
|
1.04 (1.02, 1.05)
|
59.69%
|
LAP
|
1.05 (0.99, 1.12)
|
1.01 (1.00, 1.01)
|
18.54%
|
VAI
|
1.06 (0.99, 1.13)
|
1.00 (0.99, 1.01)
|
7.81%
|
Vitamin B group
|
|
|
|
BMI
|
0.90 (0.84, 0.96)
|
0.95 (0.94, 0.97)
|
28.31%
|
WC
|
0.90 (0.83, 0.96)
|
0.95 (0.94, 0.97)
|
28.95%
|
LAP
|
0.87 (0.81, 0.93)
|
0.98 (0.97, 0.99)
|
8.49%
|
VAI
|
0.86 (0.81, 0.92)
|
0.99 (0.99, 1.00)
|
2.48%
|
RRRb
|
|
|
|
High fat and low vitamin diet
|
|
|
|
BMI
|
0.99 (0.94, 1.05)
|
1.08 (1.06, 1.09)
|
NAc
|
WC
|
0.98 (0.93, 1.04)
|
1.09 (1.07, 1.10)
|
NAc
|
LAP
|
1.07 (0.99, 1.11)
|
1.01 (1.01, 1.03)
|
27.77%
|
VAI
|
1.07 (1.01, 1.13)
|
1.01 (1.00, 1.01)
|
6.49%
|
Mediation analysis was adjusted for smoking, drinking, vigorous physical activity, pox ratio, creatinine level, energy intake, the history of diabetes, hypertension, cardiovascular diseases, cancer, liver disease and dyslipidemia.
a PCA is the method of principal component analysis and including “Lower energy diet”, “Low vitamin A, C, K pattern” and “Vitamin B group” 3 nutrient patterns.
b RRR stands for Reduced Rank Regression and including “High fat and low vitamin diet” pattern which is related to obesity.
c NA means the proportion of indirect effects could not be explained because the direction of indirect and direct effect is opposite.
Sensitivity Analyses
Sensitivity analysis showed similar results that “Vitamin B group” and “High fat and low vitamin pattern” were significantly associated with urate level (Supplemental Table S4). In addition, all four nutrient patterns were correlated with BMI, WC and LAP (Supplemental Table S5), which were also shown to be important mediators in the nutrient patterns and uric acid pathways (Supplemental Table S6).