Objective To systematically review the relationship between helicobacter pyloric (HP) infection and ischemia stroke. Methods We searched MEDLINE, BIOSIS, VIP, and China Full Text Journal databases to identify the studies that studied the relationship between HP infection and ischemia stroke. All the studies were strictly screened according to the inclusion criteria, and meta-analyses were performed for the included studies using RevMan 4.2 software.Results Eleven case-control studies involving 1 530 patients with ischemia stroke and 1 451 health controls were included. The results of meta-analyses showed that there was a significant difference in the infection ratio of HP between the patients with ischemia stroke and health controls (OR=1.77, 95%CI 1.38 to 2.28, Plt;0.0001), but this difference was not been found after adjusting some related risk factors (1.22, 95%CI 0.93 to 1.59, P=0.15). The results of subgroup meta-analyses showed these differences were only found in the LAA (large-artery atherosclerosis) subgroup (OR=3.65, 95%CI 2.58 to 5.17) and the SAA (small-artery atherosclerosis) subgroup (OR=1.74, 95%CI 1.30 to 2.34), but was not found in the CE (cardiogenic cerebral embolism) subgroup (OR=1.08, 95%CI 0.58 to 2.02). Conclusion HP infection is associated with ischemia stroke, but the relationships between HP infection and the subtypes of ischemia stroke are different. The association between HP and LAA is ber than that between HP and the other subtypes. More evidence is needed to prove whether Helicobacter pyloric infection is an independent risk factor of ischemia stroke.
Objective To review the association between chlamydia pneumoniae (CP) infection and cerebral infarction. Methods We electronically searched MEDLINE, BIOSIS, VIP database, and China Full Text Journal Database from Jan. 1990 through Dec. 2007 to identify case-control studies about the association of CP and cerebral infarction. The quality of the included studies was assessed and the RevMan 4.2 software was used for meta-analyses. Results A total of 22 studies were included. The results of meta-analyses showed: ① When the microimmunofluorescence (MIF) method was used to examine CP antibody in serum, the positive rate of the cerebral infarction group was higher than that of the control group when the positive infection was defined by IgA≥1?16 [n=8, OR=2.18, 95%CI (1.49 to 3.49), Plt;0.0001]; but when positive infection was defined by IgA≥1?32 (n=3), IgG≥1?32 (n=6), or IgG≥1?64 (n=5), there were no significant differences in the positive rate between the two groups [OR (95%CI) were 1.47 (0.97 to 2.24), 1.24 (0.82 to 1.86), and 1.23 (0.98 to 1.55), respectively]; ② When the ELISA method was used to examine CP-IgG antibody in serum, the positive rate of the cerebral infarction group was higher than that of the controlled group [n=8, OR=2.40, 95%CI (1.42 to 4.06), P=0.000 2]. ③ The acute and chronic CP infections were associated with the incidence of cerebral infarction [n=4, OR=7.22, 95%CI (2.68 to 19.49); n=4, OR=4.30, 95%CI (3.40 to 7.40)]. Conclusion ① The association between CP infection and cerebral infarction is determined by the positive criterion. IgA antibody is more sensitive than the IgG antibody. When the positive infection is determined by IgA≥1?16, CP infection is associated with cerebral infarction. ② The results of ELISA for examining CP-IgG support the association between CP infection and cerebral infarction. ③ Both acute and chronic CP infections are associated with cerebral infarction, but these associations needed to be proven by more scientific studies.