Persistent Helicobacter pylori infection for more than 3 years leads to elevated serum homocysteine concentration: A retrospective cohort study based on a healthy Chinese population

The relationship between the Helicobacter pylori (H. pylori) infection and homocysteine is unclear. We evaluated the effect of H. pylori on serum homocysteine in a healthy Chinese population. A total of 21 184 individuals aged over 18 years underwent 13 C/14 C urease breath test (13 C/14 C-UBT) and blood tests and 5042 individuals with follow-up intervals greater than 6 months. Homocysteine levels are classified according to the Chinese expert consensus. The rates of H. pylori infection of normal level, mild level, moderate level, and severe level were 40.9%, 43.8%, 45.8%, and 46.6%, respectively (P = 0.000). H. pylori infection increased the risk of higher homocysteine concentration (OR = 1.406, P = 0.000). In the case-control study, the rates of persistent negative, new infection, persistent infection, and eradication infection were 43.6%, 11.2%, 22.9%, and 22.3%, respectively. The percentage of changes in serum homocysteine levels varied significantly among the different H. pylori infection statuses only in mild level (P = 0.024). Mean changed homocysteine values were higher in the subgroup of persistent infection than in the persistent negative subgroup (P = 0.004) and the eradication infection subgroup (P = 0.034). Serum homocysteine values were elevated only in the subgroup with over 3 years interval time and persistent infection (n = 107, mean paired differences = 1.1 ± 4.6 μmol/L, P = 0.014). There is a relationship between H. pylori and serum homocysteine, and persistent infection leads to elevation of the latter.