Mediterranean Diet is Associated with Reduced Risk of Abdominal Aortic Aneurysm in Smokers: Results of Two Prospective Cohort Studies.

OBJECTIVE

Smoking is a strong risk factor for the development of abdominal aortic aneurysm (AAA). It was hypothesised that a Mediterranean diet via its anti-oxidative properties would decrease the risk of AAA, particularly among smokers.

METHODS

The study population included the Cohort of Swedish Men (45 072 men) and the Swedish Mammography Cohort (36 632 women), aged 45 - 83 years at baseline. A modified Mediterranean Diet (mMED) score, including eight food groups, was calculated based on a food frequency questionnaire. Cox proportional hazard models were used to estimate hazard ratios (HRs) with 95% confidence intervals (CIs).

RESULTS

During 17.5 years of follow up (1 427 841 person-years), 1 781 AAA cases (1 496 in men, 285 in women; 1 497 non-ruptured, 284 ruptured) were ascertained via Swedish registers. The mMED score was inversely associated with AAA incidence in men (per each one point increment in mMED score HR 0.96, 95% CI 0.93 - 1.00) and in women (HR 0.83, 95% CI 0.77 - 0.90), for non-ruptured (HR 0.95, 95% CI 0.92 - 0.99; in men with infrarenal aortic diameter ≥ 30 mm HR 0.90, 95% CI 0.81 - 1.00) and for ruptured AAA (HR 0.81, 95% CI 0.70 - 0.93). In current and ex-smokers with low (< 20) and moderate (20 - 39.9) pack-years of smoking, a statistically significant inverse association was observed. HRs for each one point increment in the mMED score in current smokers were 0.83 (95% CI 0.75 - 0.91) and 0.90 (95% CI 0.84 - 0.97), respectively; in ex-smokers 0.89 (95% CI 0.81 - 0.97) and 0.93 (95% CI 0.85 - 1.01), respectively. No association was observed among current or ex-smokers with ≥ 40 pack-years; HRs 1.02 (95% CI 0.91 - 1.13) and 0.95 (95% CI 0.83 - 1.10), respectively.

CONCLUSION

Adherence to the Mediterranean diet was associated with a reduced AAA risk in current and ex-smokers with low pack-years of smoking.