There are many studies showing the prevalence and correlation of Hp in diabetic patients [8, 9, 10, 11, 12]. Studies by Ciortescu et al.  and Demir et al.  showed a significant increase in Hp prevalence in diabetic cases compared to the normal population. Gulcelik et al. reported Hp prevalence increased in another study of diabetic patients and that this may be due to slowed stomach emptying and bacterial increases as a result of diabetic-linked autonomic neuropathy . Along with studies showing Hp infection is more common in men [14, 15, 16, 17, 18, 19], a study by Lu et al. did not show a significant difference between gender and Hp presence , overlapping with our study.
In the literature there are many studies showing the correlation between Hp and atherosclerosis [6, 17, 18]. Some studies showed that Hp infection caused microvascular injury which triggers the initial stage of atherosclerosis [13, 18]. A study by Franceschi et al. reported that the interaction between Hp antibody and vein wall antigens may play a role in atherosclerosis development . Another study of diabetic patients by Hamed et al. identified that the increase in intima media thickness in Hp infection may play a role in development of atherosclerosis and CAD by causing atherosclerotic plaque formation through invasion of the vein wall .
There are many studies researching the relationship between Hp and lipid profile in the literature. A study by Rahman et al. compared lipid profiles between Hp positive cases with and without CAD and identified no significant changes in total cholesterol, triglyceride and LDL cholesterol values, but HDL cholesterol was low in both groups . A study by Laurila et al.  found similar results with high total cholesterol and triglyceride values and similar HDL cholesterol values in Hp positive cases compared to negative cases. Another study  showed lower HDL cholesterol value in Hp positive cases compared to negative ones. A different study identified LDL cholesterol values were high in Hp positive individuals . Vafaeimanesh et al.  found no significant difference in lipid parameters in Hp positive or negative cases, similar to our study. This result may be linked to the low number of participants in the study and patients who attended regular clinical follow-up beginning lipid-lowering treatment in the early period.
A study by Su et al. showed the effect of BAG and BGT on endothelial dysfunction . Another study identified a reduction in plasma glucose levels with Hp eradication treatment . While there are studies showing higher fasting plasma glucose in Hp positive cases compared to negative cases [15, 26], our study showed no significant effect of Hp positivity on fasting plasma glucose. This result may be linked to the use of medications effective on insulin resistance at similar rates in Hp positive and negative cases participating in the study and patients regularly attending clinical check-ups.
There are studies showing a relationship between microalbuminuria, an early clinical marker of diabetic nephropathy, with endothelial dysfunction and subclinical atherosclerosis [27, 28]. A study by Chung et al. identified that Hp positivity was independently associated with the presence of microalbuminuria and urine albumin creatinine ratio had positive correlation with severity . In our study, we showed the presence of Hp had no significant effect on albumin creatinine ratio and GFR level. Different from these studies, this result may be linked to the Hp positive and negative cases included in the study having similar risk factors for microvascular complications. In the study, Hp positive and negative cases did not have significant differences between diabetic duration and RAS blocker use so the actual effect on albumin creatinine ratio and GFR level may be inferred to be RAS blocker use and diabetic duration, rather than Hp.
The inflammation parameter of CRP was shown to increase CAD risk in many studies [30, 31]. A study by Jackson et al. compared the CRP levels of Hp positive and negative cases and showed Hp positive vases had higher CRP level . Similar to our study results, Vafaeinmanesh et al. identified no significant effect of Hp presence on CRP elevation .
There are studies showing Hp positivity in adults is positively correlated with disrupted glucose tolerance [33, 34]. In this context, the study by Chen et al.  identified a significant relationship between Hp positivity in diabetic patients with HbA1c elevation. A study by Dai et al. identified higher HbA1c levels in type 1 diabetic patients with Hp positivity but reported there was no significant effect of Hp positivity on HbA1c levels in type 2 diabetic patients . In our study, Hp presence was not shown to have a significant effect on HbA1c levels, supporting the findings of a study completed by Horikawa et al. .
In the literature, there are studies showing increased intima media thickness with BMI, a marker of obesity . When considered in terms of the presence of Hp, there was a positive significant correlation reported between Hp positivity and BMI  and BMI of Hp positive patients was higher compared to negative patients . In our study, the presence of Hp had no significant effect on BMI.
Atherosclerosis is an inflammatory disease beginning in the early periods of life progressing with arterial vein wall deformation. Arterial wall thickness is an early marker of atherosclerosis and may be easily assessed with Doppler ultrasound. There are many studies showing Hp positivity causes an increase in intima media thickness [14, 27]. A study by Zhang et al. in China showed presence of Hp had a positive effect on CIMT in men under 50 years of age; however, there was no significant effect in women and men over 50 years of age . In our study, similar to the study by Zhang et al., we observed Hp positivity significantly increased CIMT.
In the literature, there are many studies showing Hp infection increases plaque formation in the carotid artery [40, 41]. Hu et al. showed high HbA1c value accompanying Hp positivity was closely associated with plaque formation in the carotid artery . In our study, Hp positivity did not have a significant effect on plaque formation. This result leads to consideration that the basis of plaque formation in the carotid artery is not the presence of Hp, but is associated with the elevation in HbA1c. In fact, patients with increased plaque formation in the carotid artery were reported to differentiate not just in terms of the presence of Hp but also in terms of HbA1c elevation in the study by Hu et al. . In our study, the reason for the lack of observation of a significant correlation between Hp presence and carotid artery plaque formation may be the similar HbA1c levels in both groups.
Limitations of our study include the lack of prospective study and the low number of patients. However, strong aspects of our study include research of the presence of Hp with endoscopic methods and detailed knowledge of medications used by participants.