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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Age Factors, Aged, Aged, 80 and over, Aortic Aneurysm, Abdominal, Biomarkers, Comorbidity, Cross-Sectional Studies, Genetic Predisposition to Disease, Homocysteine, Homozygote, Humans, Hyperhomocysteinemia, Immunoassay, Linear Models, Logistic Models, Male, Methylenetetrahydrofolate Reductase (NADPH2), Multivariate Analysis, Odds Ratio, Phenotype, Polymerase Chain Reaction, Polymorphism, Genetic, Risk Assessment, Risk Factors, Sex Factors, Ultrasonography, Up-Regulation, Western Australia.
user
Is plasma total homocysteine associated with abdominal aortic aneurysm and aortic diameter in older men? Context: This study was conducted to determine whether plasma total homocysteine (tHcy) and the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism are associated with abdominal aortic aneurysm (AAA) and aortic diameter. This was a cross-sectional study set in Western Australia of 4248 community-dwelling men aged 70 to 88 years. Infrarenal aortic diameter was measured using ultrasound scan, tHcy was measured by immunoassay, and MTHFR 677T polymorphism was detected by polymerase chain reaction. Adjusted multinomial logistic regression analysis showed the odds of having an AAA (aortic diameter ≥ 30 mm) for men with high tHcy (≥ 15 μmol/L) compared with those with normal tHcy (<15 μmol/L) was 1.45 (95% confidence interval [CI], 1.10-1.91). Every 5-μmol/L increment in tHcy was associated with 0.15-mm (95% CI, 0.01-0.28 mm) increase in mean aortic diameter. The tHcy concentration was higher in MTHFR TT homozygote individuals than in wild-type CC individuals. There was, however, no apparent association between MTHFR C677T polymorphism with AAA (TT vs CC genotype: odds ratio, 0.97; 95% CI, 0.72-1.31) or aortic diameter (TT vs CC genotype: mean increment of 0.01 mm; 95% CI, -0.63 to 0.65 mm).
assistant
Elevated tHcy is associated with the presence of AAA in older men. There is also a positive dose-response relationship between tHcy and abdominal aortic diameter. Longitudinal studies and clinical trials of lowering tHcy are required to assess whether these relationships are causal. Final Decision: yes