Association Between Serum Uric Acid and Non-Alcoholic Fatty Liver Disease: An Updated Systematic Review and Meta-Analysis

Figures & data

Figure 1 Flow chart of study selection in the meta-analysis.

Table 1 Summary of the Characteristics of Included Studies (Association Between SUA Levels and NAFLD)^a

Characteristics	Overall
Number of studies	50
Sample size (median value) (N %)
≤4149	24 (48.00)
>4149	26 (52.00)
Age (year) (N %)
≤44	19 (38.00)
45–59	22 (44.00)
≥60	3 (6.00)
Not available	6 (12.00)
Follow-up (year) (N %)
≤2	28 (56.00)
>2	18 (36.00)
Not available	4 (8.00)
Study design (N %)
Cohort Study	13 (26.00)
Cross-Sectional Study	36 (72.00)
Case-Control Study	1 (2.00)
Comparison (N %)
T3 vs T1	2 (4.00)
Q4 vs Q1	24 (48.00)
Q5 vs Q1	4 (8.00)
HUA (+) vs HUA (-)	22 (44.00)
Gout (+) vs Gout (-)	1 (2.00)
Elevated SUA vs normal SUA	1 (2.00)
Study quality (N %)
<7	27 (54.00)
≥7	23 (46.00)
Country (N %)
China	40 (80.00)
Korea	6 (12.00)
USA	2 (4.00)
Japan	1 (2.00)
Italy	1 (2.00)

Note: ^aA total of 50 studies were included, with 54 estimates.

Abbreviations: T3 vs T1, Highest vs lowest tertile; Q4 vs Q1, Highest vs lowest quartile; Q5 vs Q1, Highest vs lowest quintile; HUA, hyperuricemia; SUA, serum uric acid.

Table 2 Subgroup Analysis for Articles Included in the Meta-Analysis of Associations Between SUA Levels and NAFLD

Subgroup Analysis	Number of Estimates	OR (95% CI)	P value	I^2 (%)
Study design
Cohort Study	14	1.73 (1.52–1.97)	<0.001	77.10%
Cross-sectional Study	39	1.91 (1.79–2.05)	<0.001	81.20%
Case-control Study	1	5.92 (3.39–10.33)	–	–
Sex
Male	14	1.76 (1.53–2.01)	<0.001	77.60%
Female	14	2.09 (1.77–2.47)	<0.001	68.00%
Study quality
<7	28	1.97 (1.82–2.15)	<0.001	68.10%
≥7	26	1.79 (1.61–1.99)	<0.001	89.10%
Sample size (median value)
≤4149	26	2.17 (1.91–2.47)	<0.001	55.50%
>4149	28	1.77 (1.64–1.91)	<0.001	90.80%
Comparison
Q4 vs Q1	24	1.95 (1.76–2.17)	<0.001	69.50%
HUA (+) vs HUA (-)	22	1.73 (1.58–1.90)	<0.001	87.50%
Q5 vs Q1	4	2.50 (1.57–3.99)	<0.001	91.90%
T3 vs T1	2	2.26 (1.32–3.89)	0.860	0.00%
Gout (+) vs Gout (-)	1	1.42 (1.26–1.61)	–	–
Elevated SUA vs Normal SUA	1	2.12 (1.85–2.42)	–	–
Age^a
≤44	19	1.76 (1.55–2.00)	<0.001	83.10%
45–59	22	1.96 (1.77–2.17)	<0.001	65.20%
≥60	3	3.42 (1.60–7.33)	<0.001	94.20%
Country
China	42	1.96 (1.83–2.10)	<0.001	82.40%
Korea	7	1.57 (1.34–1.83)	0.001	73.00%
USA	3	1.46 (1.25–1.70)	0.721	0.00%
Japan	1	2.00 (1.42–2.82)	-	-
Italy	1	3.01 (1.40–6.48)	-	-

Note: ^aThere are 10 estimates that do not provide age of subjects.

Abbreviations: T3 vs T1, Highest vs lowest tertile; Q4 vs Q1, Highest vs lowest quartile; Q5 vs Q1, Highest vs lowest quintile; HUA, hyperuricemia; SUA, serum uric acid; CI, confidence interval.

Figure 2 Overall pooled OR of association between SUA and NAFLD.

Table 3 Results of Meta-Regression Analysis

Variable	Coef	SE	t	P
Study design	5.920	2.163	4.87	<0.001
Study quality	2.959	0.686	4.68	<0.001
Sample size	2.171	0.145	11.57	<0.001
Comparison	2.115	0.528	3.00	0.004
Country	2.000	0.606	2.29	0.027
Age	1.852	0.131	8.70	<0.001

Abbreviations: SE, Standard error; Coef, coefficient.

Figure 3 Prevalence and incidence rate of NAFLD in patients with hyperuricemia.