Infection by Helicobacter pylori and acute myocardial infarction. Do cytotoxic strains make a difference?
The classical risk factors for acute myocardial infarction (AMI) fail to explain all the epidemiological variations of the disease. Among the risk factors recently reported, several infectious agents appear to increase the risk of AMI. Helicobacter pylori (H. pylori) infection, a bacterium involved in duodenal and gastric ulcer, gastric cancer and MALT-lymphoma, seems to be strongly associated with AMI. More virulent (anti-CagA positive) strains of the bacterium are almost exclusively the causative agents of such diseases. To determine the prevalence of H. pylori infection and of virulent strains, a case-control study was conducted in a group of male patients with AMI. A group of patients consecutively admitted to the Emergency Care Unit served as controls. We studied 223 consecutive male patients, mean age 60.2 (range 40-79) years, admitted for AMI to the Coronary Care Units at Hospitals in two towns of Northern Italy, 223 age matched male patients (mean age 61.8, range 40-79 years) admitted to the Emergency Care Unit, served as control. H. pylori seroprevalence was assessed by presence of antibodies (IgG) against H. pylori and anti-CagA in circulation. Among the patients we investigated the presence of hypertension, levels of cholesterol and glucose in serum, fibrinogen in plasma and smoking habits. H. pylori infection was present in 189/223 (84.7%) of the patients and in 138/223 (61.8%) of the control population (p < 0.0001 OR 3.42 [IC 95% 2.12-5.54]). The anti-CagA antibodies were detected in 33.8% of infected patients with AMI (64/189) versus 26.8% in the control subjects (37/138) (p:0.17, OR 1.40 [IC 95% 0.84-2.33]). Classical risk factors for AMI did not differ among patients with and without H. pylori infection. Patients admitted to the Coronary Care Unit for acute myocardial infarction had a notably higher prevalence of anti-H. pylori not restricted to virulent strains, when compared to a population of patients referred to the Emergency Care Unit. The classical risk factors for coronary disease were present in the patients with AMI irrespective of H. pylori status.
Pellicano
R
R
Department of Gastro-Hepatology, Molinette Hospital, Turin, Italy.
Parravicini
P P
PP
Bigi
R
R
Gandolfo
N
N
Aruta
E
E
Gai
V
V
Figura
N
N
Angelino
P
P
Rizzetto
M
M
Ponzetto
A
A
D000328:Adult; D000367:Age Factors; D000368:Aged; D000907:Antibodies, Bacterial / Q000097:blood; D000942:Antigens, Bacterial; D001426:Bacterial Proteins / Q000378:metabolism; D015153:Blotting, Western; D016022:Case-Control Studies; D005340:Fibrinogen / Q000378:metabolism; D016481:Helicobacter Infections / Q000097:blood / Q000150:complications* / Q000453:epidemiology; D016480:Helicobacter pylori / Q000472:pathogenicity*; D006801:Humans; D006943:Hyperglycemia / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000382:microbiology*; D015995:Prevalence; D012307:Risk Factors; D014774:Virulence
D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C080866:cagA protein, Helicobacter pylori; D005340:Fibrinogen