Dietary iron intake and risk of non-fatal acute myocardial infarction.
OBJECTIVE
The relation between several measures of body iron and atherosclerotic disease, particularly acute myocardial infarction (AMI), is debated. This is of specific interest since iron is frequently included in supplementation and fortification of foods. We assessed the relation between dietary iron intake and the risk of non-fatal AMI.


METHODS
Case-control study. The information was collected by interviewers using a food-frequency questionnaire tested for validity and reproducibility. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were obtained by multiple unconditional logistic regression models, including terms for energy and alcohol intake, as well as for sociodemographic factors, tobacco and other major recognised risk factors for AMI.


METHODS
Milan, Italy, between 1995 and 1999.


METHODS
Cases were 507 patients, below age 79 years, with a first episode of non-fatal AMI, and controls were 478 patients admitted to hospital for a wide spectrum of acute conditions unrelated to known or potential AMI risk factors.


RESULTS
Compared with patients in the lowest tertile of total iron intake, the OR was 0.48 (95% CI 0.29-0.82) for those in the highest tertile. The corresponding value for haem iron was 0.71 (95% CI 0.48-1.06), for non-haem, non-alcohol iron was 0.80 (95% CI 0.51-1.24) and for iron derived from alcoholic beverages was 0.60 (95% CI 0.40-0.90). Sex-specific OR for total iron intake were not heterogeneous.


CONCLUSIONS
In this Italian population dietary iron intake was inversely related to AMI risk. This inverse association may depend on other nutrients present in the major sources of iron in the Italian diet.
Tavani
Alessandra
A
Istituto di Ricerche Farmacologiche Mario Negri, Via Eritrea 62, I-20157 Milan, Italy. tavani@marionegri.it
Gallus
Silvano
S
Bosetti
Cristina
C
Parpinel
Maria
M
Negri
Eva
E
La Vecchia
Carlo
C
D000208:Acute Disease; D000368:Aged; D000428:Alcohol Drinking; D016022:Case-Control Studies; D016001:Confidence Intervals; D004032:Diet; D005260:Female; D006801:Humans; D019266:Iron, Dietary / Q000008:administration & dosage*; D007558:Italy / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood* / Q000453:epidemiology*; D016017:Odds Ratio; D012307:Risk Factors; D011795:Surveys and Questionnaires
D019266:Iron, Dietary