Vitamin D levels do not predict the stage of hepatic fibrosis in patients with non-alcoholic fatty liver disease: A PRISMA compliant systematic review and meta-analysis of pooled data

Table 3 Characteristics of patients’ studies for vitamin D status in non-alcoholic fatty liver disease

Citation	Patel et al[32]	Luger et al[30]	Barchetta et al[28]	Anty et al[27]	Dasarthy et al[24]	Bril et al[29]	Nelson et al[31]	Targher et al[26]
Year	2016	2016	2012	2016	2014	2015	2016	2007
Country	United States	Austria	Italy	France	United States	United States	United States	Italy
Subjects (M, F)	293 (195, 98)	50 (10, 40)	45 (22, 23)	398 (64, 334)	187 (51, 136)	239 (204, 35)	190 (89, 101)	120 (80, 40)
Population	Suspected NAFLD undergoing liver biopsy	Gastric bypass patients	Suspected NAFLD	Morbidly obese referred for bariatric surgery	Biopsy proven NAFLD, normal controls	Overweight patients	Biopsy proven NAFLD	Biopsy proven NAFLD
Mean BMI	36.1 ± 7.8	43.8 ± 4.3	30.5 ± 5.5	42.8 ± 5.0	35.7 ± 7.0	34.6 ± 0.4	35.6 ± 10.8	26.3 ± 2.0
Subjects	NAFLD	All	NASH	All	NAFLD	NASH	NAFLD	NAFLD
Mean ± SD ALT IU/L	66.5 ± 51.2	36.4 ± 20.8	87.5 ± 46.6	35.2 ± 24.5	45.9 ± 30.0	64.0 ± 4.0	77.0 ± 48.2	105 ± 42.0
Subjects	NAFLD	All	NASH	Morbidly Obese	NAFLD	NASH	NAFLD	NAFLD
Study design	Cross sectional	Cross sectional	Cross sectional	Cross sectional	Cross sectional	Cross sectional	Cross sectional	Cross sectional
Vitamin D analysis	CLIA	Not described	CLIA	CLIA	CLIA	CLIA	GC-MS	CLIA
Mean/SD 25(OH)D (ng/mL), (n) subjects	27.6 ± 11.8	15.6 ± 5.6	22.0 ± 12.4	19.2 ± 9.0	21.2 ± 10.4	21.8 ± 1.0	20.9 ± 4.0	20.4 ± 8.8
Mean/SD 25(OH)D (ng/mL) Non-NAFLD Controls	27.9 ± 12.8	NA	52.9 ± 11.02	21.5 ± 10/2	35.7 ± 6.0	24.5 ± 2.1	NA	30.0 ± 6.0
P value; NAFLD vs controls	0.878	NA	Not significant	0.13	< 0.01	0.18	NA	< 0.001

n: Number of subjects; 25-OH(D): 25-hydroxylvitamin D; SD: Standard deviation; NAFLD: Nonalcoholic fatty liver disease; NASH: Nonalcoholic steatohepatitis; BMI: Body mass index; CLIA: Chemiluminescence; GC-MS: Gas chromatography mass spectroscopy; M: Male; F: Female.