Table 2 Determining the odds ratio with the confidence interval of association between Helicobacter pylori infection and metabolic syndrome and insulin resistance in case–control studies based on variables of detection methods of infection, study populations, age, body mass index, and the continents of the world

Metabolic Syndrome

Method of bacteria detection

Anti- H. pylori antibody

5

1.26 (1.01–1.70)

0.0%

0.852

1.38

0.19

0.910

 Rapid urease test

1

1.26 (0.53–3.00)

–

–

–

 C urea breath test (UBT)

5

1.17 (0.02–1.35)

0.0%

0.830

1.49

BMI

0.13

0.71

 < = 24

3

1.25 (0.92–1.69)

0.0%

0.731

0.62

 > 24

5

1.36 (1.01–2.00)

0.0%

0.977

1.63

Age

0.56

 < = 45

5

1.16 (1.00–1.35)

0.0%

0.771

1.78

0.32

0.32

 > 45

6

1.26 (1.00–1.89)

0.0%

0.964

0.96

Insulin Resistance

Method of bacteria detection

Anti- H. pylori antibody

7

1.63 (1.25–2.12)

0.0%

0.990

2.71

0.44

0.661

 Rapid urease test (RUT) & Histology

3

1.33 (0.56–3.16)

67.1%

0.043

6.64

Type of diabetes

 Diabetes dellitus

5

1.19 (1.00–1.78)

0.0%

0.890

4.37

3.33

0.192

 Gestational diabetes

1

2.80 (0.39–19.92)

–

–

–

 NIDDM

4

1.80 (1.34–2.42)

0.0%

0.510

2.33

Population

 Male

4

1.19 (1.00–1.78)

0.0%

0.990

0.08

0.23

0.89

 Female

4

2.80 (0.39–19.92)

0.0%

0.940

0.38

 Both

7

1.80 (1.34–2.42)

44.1%

0.152

9.36

Continent

 Asia

5

1.67 (1.23–2.26)

0.0%

0.764

1.85

1.72

0.63

 America

7

1.47 (0.89–2.44)

0.0%

0.930

0.58

 Africa

2

1.00 (0.26–3.77)

47.6%

0.173

1.91

 Europe

1

2.35 (1.16–4.73)

–

–

–

BMI

 < = 29

5

1.04 (0.60–1.79)

12.2%

0.488

3.46

0.84

0.36

 > 29

7

1.47 (0.89–2.44)

0.0%

0.662

0.55

Age

 <= 45

8

1.09 (0.70–1.70)

2.5%

0.770

4.05

0.99

0.77

 > 45

7

1.77 (1.35–2.33)

0.0%

0.872

2.40