Association between body mass index and erosive esophagitis: A meta-analysis

Table 1 Study characteristics

Authors	Yr	Design	Region	Population size	Case population	Reference population	Confounders adjusted for
Ha et al[43]	2010	Case-control	South Korea	n = 292 (EE), n = 500 (NERD)	Single hospital	Hospital controls	G, E, T, J, OD, WHR, TG
Nam et al[44]	2010	Cohort	South Korea	n = 495 (EE), n = 3779 (normal)	General population	General population	WC , WHR , VAT , SAT
Wang et al[46]	2010	Case-control	China	n = 70 (EE), n = 502 (non-EE)	General population	General population	A, G, S, B, T, E, C, tea drinking, spicy food consumption, betel nut use
Koo et al[45]	2009	Case-control	South Korea	n = 42 (EE), n = 987 (control)	General population	General population	G, T, E, TG ,
Koo et al[45]	2009	Case-control	South Korea	n = 42 (EE), n = 1007 (control)	General population	General population	G, T, E, TG ,
Chua et al[47]	2009	Case-control	Taiwan, China	n = 427 (EE), n = 427 (control)	Single hospital	Hospital controls	TG, Glucose intolerance, HDL-C, SBP
Song et al[48]	2009	Case-control	South Korea	n = 639 (EE), n = 5443 (non-EE)	Single hospital	Hospital controls	A, G, T, E, H, TC, HDL-C, LDL-C, TG, BP, fasting glucose
Lien et al[49]	2009	Case-control	Taiwan, China	n = 102 (EE), n = 1942 (non-EE)	Single hospital	Hospital controls	A, G, J
Lien et al[49]	2009	Case-control	Taiwan, China	n = 240 (EE), n = 1662 (non-EE)	Single hospital	Hospital controls	A, G, J
Nam et al[50]	2009	Cohort	South Korea	n = 552 (EE), n = 8019 (non-EE)	General population	General population	A, WC, E, T
Lee et al[51]	2009	Case-control	South Korea	n = 100 (EE), n = 100 (control)	Single hospital	Hospital controls	WHR, T, J, VAT, SAT, VAT/SAT
Chung et al[52]	2008	Case-control	South Korea	n = 3539 (EE), n = 3539 (control )	Single hospital	Hospital controls	E, T, metabolic syndrome
Zagari et al[53]	2008	Cross-sectional	Italy	n = 122 (EE), n = 911 (non-EE)	General population	General population	A, G, E, T, H, J, C, medication use, peptic ulcer
Lee et al[54]	2008	Case-control	South Korea	n = 292 (EE), n = 2896 (control)	Medical center	Medical center	G, TC, TG, WHR, J, T, OD, PBF
Kim et al[42]	2008	Case-control	South Korea	n = 1810 (EE), n = 20154 (normal)	Multiple hospital	Multiple hospital	G, E, J, H, TC, TG, T, medications for liver/heart disease
Moki et al[56]	2007	Case-control	Japan	n = 191 (EE), n = 4968 (non-EE)	General population	General population	A, G, BP, TG, FBG
Kim et al[58]	2007	Case-control	South Korea	n = 1090 (EE), n = 26229 (non-EE)	Single hospital	Hospital controls	A, G, E, T
Nocon et al[55]	2007	Cohort	Germany	n = 5289 (EE), n = 926 (non-EE)	General population	General population	A, T, E,
Kang et al[57]	2007	Cross-sectional	South Korea	n = 161 (EE), n = 2281 (non-EE)	Single hospital	Hospital controls	A, G, J, T, B, hypertensive drugs, lifestyle choices, abdominal obesity
Labenz et al[8]	2004	Cross-sectional	Germany	n = 2455 (EE), n = 2834 (control)	Medical center	Medical center	A, G, R, S, T, E, B, H, concomitant disease, concomitant medicatons
Nilsson et al[12]	2002	Case-control	Sweden	n = 179 (EE), n = 179 (control)	Multiple hospital	Multiple hospital	T, cholecystectomy, I, drugs use
Wilson et al[59]	1999	Case-control	United States	n = 189 (EE), n = 1024 (control)	Single hospital	Single hospital	A, G, J, R
Stene-Larsen et al[4]	1988	Cross-sectional	Sweden	n = 195 (EE), n = 1029 (control)	Single hospital	Single hospital	None

A: Age; B: Aspirin or NSAID intake; C: Coffee; D: Meal size; E: Alcohol/ethanol; F: Family history; G: Gender; H: Helicobacter pylori infection; I: Asthma or asthma medication; J: Hiatal hernia; K: Hospital visit or hospitalization; M: Marital status; O: Symptom checklist-90 score; P: Physical activity; Q: Psychosomatic symptoms; R: Race; S: Socioeconomic status, education; T: Tobacco; W: Right handedness; V: Comorbidity; X: Case control status; Y: Birthplace; Z: Hormone replacement therapy; VAT: Visceral adipose tissue; SAT: Subcutaneous adipose tissue; BP: Blood pressure; SBP: Systolic; DBP: Diastolic blood pressure; TC: Total cholesterol; HDL-C: High-density lipoprotein cholesterol; LDL-C: Low-density lipoprotein cholesterol; TG: Triglyceride; HbAlc: Hemoglobin Alc; OD: Obesity degree; WHR: Waist-to-hip ratio; WC: Waist circumference; PBF: Percentage of body fat; FBG: Fasting blood glucose; EE: Erosive esophagitis; NERD: Non-erosive reflux disease; NSAID: Nonsteroidal antiinflammatory drugs.

Table 2 Exposure and outcome definitions

Authors	Yr	Exposure (source)	BMI reference (kg/m2)	Exposure (definitions)			Outcome (source)	Outcome (definitions)
				BMI overweight(kg/m2)	BMI obese(kg/m2)	BMI overweight + obese (kg/m2)
Ha et al[43]	2010	Measured BMI	≤ 25			≥ 25	Endoscopy	Los Angeles classification
Nam et al[44]	2010	Measured BMI	< 20	25-29.9	≥ 30	≥ 25	Endoscopy	Los Angeles classification
Wang et al[46]	2010	Measured BMI	< 25	25-30	> 30	≥ 25	Endoscopy	Los Angeles classification
Koo et al[45]	2009	Measured BMI	< 23	23-24.9	≥ 25	≥ 23	Endoscopy	Los Angeles classification
Koo et al[45]	2009	Measured BMI	< 23	23-24.9	≥ 25	≥ 23	Endoscopy	Los Angeles classification
Chua et al[47]	2009	Self-report	< 25		≥ 25	≥ 25	Endoscopy	Los Angeles classification
Song et al[48]	2009	Measured BMI			≥ 30		Endoscopy	Los Angeles classification
Lien et al[49]	2009	Self-report	< 24	24-26.9	≥ 27	≥ 24	Endoscopy	Modified Savary-Miller endoscopic classification
Lien et al[49]	2009	Self-report	< 24	24-26.9	≥ 27	≥ 24	Endoscopy	Modified Savary-Miller endoscopic classification
Nam et al[50]	2009	Self-report	< 20	25-29.9	≥ 30	≥ 25	Endoscopy	Los Angeles classification
Lee et al[51]	2009	Measured BMI	20-25	25-30	≥ 30	≥ 25	Endoscopy	Los Angeles classification
Chung et al[52]	2008	Measured BMI	< 23	23-24.9	≥ 25	≥ 23	Endoscopy	Los Angeles classification
Zagari et al[53]	2008	Self-report	20-24.9	25-29.9	≥ 30	≥ 25	Endoscopy	Modified Savary-Miller endoscopic classification
Lee et al[54]	2008	Measured BMI	< 20	25-30	> 30	≥ 25	Endoscopy	Los Angeles classification
Kim et al[42]	2008	Measured BMI	< 23			≥ 25	Endoscopy	Los Angeles classification
Moki et al[56]	2007	Measured BMI	< 25		≥ 25		Endoscopy	Los Angeles classification
Kim et al[58]	2007	Measured BMI	18.9-24.5	25-29.9	≥ 30	≥ 25	Endoscopy	Los Angeles classification
Nocon et al[55]	2007	Measured BMI		25-30	> 30		Endoscopy	Los Angeles classification
Kang et al[57]	2006	Measured BMI	< 25	25-30	> 30	≥ 25	Endoscopy	Los Angeles classification
Labenz et al[8]	2004	Measured BMI	< 25	25-30	> 30		Endoscopy	Los Angeles classification
Nilsson et al[12]	2002	Self-report	< 25	25-30	> 30	≥ 25	Endoscopy	Modified Savary-Miller endoscopic classification
Wilson et al[59]	1999	Measured BMI	< 20	25-30	> 30	≥ 25	Endoscopy	NA
Stene-Larsen et al[4]	1988	Measured BMI	< 25	25-28	> 28		Endoscopy	NA

BMI: Body mass index; NA: Not available.

Table 3 Meta-analysis results in association between body mass index and erosive esophagitis

BMI category	OR (95% CI)	Phomogeneity	I2(%)	No. of studies
Overall
Overweight	1.60 (1.35-1.88)	0.003	59.8	12[4,8,12,44,45,50,51,53,54,57-59]
Obese	2.05 (1.65-2.55)	0.000	74.2	15[4,8,12,44-46,50-54,56-59]
Overweight + obese	1.64 (1.45-1.85)	0.000	65.7	18[4,8,12,43-47,49,50-54,56-59]
Females
Overweight	1.47 (1.15-1.88)	0.011	7.4	3[12,44,55]
Obese	3.76 (0.92-15.28)	0.340	78.0	3[12,44,55]
Overweight + obese	1.45 (1.26-1.66)	0.579	0.0	4[12,44,55,56]
Males
Overweight	1.40 (1.11-1.75)	0.285	20.8	4[12,44,46,55]
Obese	1.74 (1.02-2.96)	0.099	52.1	4[12,44,46,55]
Overweight + obese	1.52 (1.24-1.87)	0.179	36.3	5[12,44,46,55,56]

BMI: Body mass index; OR: Odds ratio.