Epidemiology of Helicobacter pylori infection among the healthy population in Iran and countries of the Eastern Mediterranean Region: A systematic review of prevalence and risk factors

Table 2 Risk factors for Helicobacter pylori infection and prevalence of Anti-Cag A seropositivity in the Iranian population

Ref.	Prevalence of Anti-Cag A	Main findings and risk factors
Alborzi et al[12]	NA	The prevalence of H. pylori was significantly lower in the 15-yr-old age group compared to the < 14-yr-old age group
		Sex was not a risk factor for prevalence
Nouraie et al[13]	NA	Higher maternal education was protective against H. pylori infection
		Low education, increasing age and overcrowding were risk factors for H. pylori infection
Jafarzadeh et al[14]	72.8%	Prevalence of Anti-Hp IgG and Anti-Cag A Ab were increased with age
Jafarzadeh et al[15]	67.4%	Prevalence of Anti-Cag A Ab was higher in males than females
		Prevalence of Anti-Cag A Ab was higher in those < 30 yr
Alizadeh et al[16]	NA	Female sex and age (median 37 yr) were risk factors for H. pylori infection
		Hygienic practice and crowding were not risk factors for H. pylori infection
Ghasemi Kebria et al[17]	57.7%	No significant difference between rural and urban areas regarding prevalence
		Seroprevalence increased with increasing age
Jafar et al[18]	NA	Larger family size was associated with higher prevalence
		Increasing age was associated with H. pylori infection
Mikaeli et al[19]	NA	Increasing age was the only predictor of H. pylori infection
Mansour-Ghanaei et al[20]	NA	Water supply was a predictor of H. pylori infection
Mahram et al[21]	NA	Age and sex were not risk factors for H. pylori infection

NA: Not available; H. pylori: Helicobacter pylori.