Homocysteine and the Risk of Ischemic Stroke in a Triethnic Cohort

Abstract

Background and Purpose-The level of total homocysteine (tHcy) that confers a risk of ischemic stroke is unsettled, and no prospective cohort studies have included sufficient elderly minority subjects. We investigated the association between mild to moderate fasting tHcy level and the incidence of ischemic stroke, myocardial infarction, and vascular death in a multiethnic prospective study. Methods-A population-based cohort was followed for vascular events (stroke, myocardial infarction, and vascular death).Baseline values of tHcy and methylmalonic acid were measured among 2939 subjects (mean age, 69Ϯ10; 61% women, 53% Hispanics, 24% blacks, and 20% whites). Cox proportional models were used to calculate hazard ratios (HRs) and 95% CIs in tHcy categories after adjusting for age, race, education, renal insufficiency, B 12 deficiency, and other risk factors. Results-The adjusted HR for a tHcy level Ն15 mol/L compared with Ͻ10 mol/L was greatest for vascular death (HRϭ6.04; 95% CI, 3.44 to 10.60), followed by combined vascular events (HRϭ2.27; 95% CI, 1.51 to 3.43), ischemic stroke (HRϭ2.01; 95% CI, 1.00 to 4.05), and nonvascular death (HRϭ2.02; 95% CI, 1.31 to 3.14). Mild to moderate elevations of tHcy of 10 to 15 mol/L were not significantly predictive of ischemic stroke, but increased the risk of vascular death (2.27; 95% CI, 1.44 to 3.60) and combined vascular events (1.42; 95% CI, 1.06 to 1.88). The effect of tHcy was stronger among whites and Hispanics, but not a significant risk factor for blacks. Conclusions-Total Hcy elevations above 15 mol/L are an independent risk factor for ischemic stroke, whereas mild elevations of tHcy of 10 to 15 mol/L are less predictive. The vascular effects of tHcy are greatest among whites and Hispanics, and less among blacks. (Stroke.

Relation Between Soluble Intercellular Adhesion Molecule-1, Homocysteine, and Fibrinogen Levels and Race/Ethnicity in Women Without Cardiovascular Disease

“…In data obtained prior to folate supplementation from the National Health and Nutrition Examination Survey III, whites were noted to have the highest homocysteine levels, followed by Mexican Americans and blacks, a finding that might be due to the higher prevalence of the MTHFR 677C → T point mutation that causes decreased activity of the noted enzyme among whites (15). However, both pre and post folate fortification data from the Northern Manhattan Study show that while blacks had the highest homocysteine levels followed by whites and Hispanics, only among whites and Hispanics were these levels significantly predictive of vascular outcomes and stroke (16). In contrast to our finding, research related to homocysteine levels among South Asians residing in England as well as in Canada show that they have higher homocysteine levels than their white and black counterparts (17)(18).…”

Ideal Cardiovascular Health and Biomarkers of Subclinical Brain Aging: The Northern Manhattan Study

“…Northern Manhattan represents a well‐defined area of New York City with a unique population that was 63% Hispanic, 20% non‐Hispanic black, and 15% non‐Hispanic white during our random sampling (1993–2001). Study details have been published 12. Briefly, participants were identified using random‐digit dialing between 1993 and 2001 with the following eligibility criteria: (1) had never been diagnosed with a stroke; (2) were aged >40 years; and (3) resided in Northern Manhattan for ≥3 months, in a household with a telephone.…”

The Association between a Mediterranean-Style Diet and Kidney Function in the Northern Manhattan Study Cohort

“…The details of recruitment and assessment were previously described (23). Briefly, participants were enrolled between 1993 and 2001, and were eligible if they met the following criteria: no prior history of stroke, age .40 years, and residence in a household with a telephone in northern Manhattan.…”

“…Demographic variables and well established baseline risk factors for CKD progression were assessed as previously described and included in multivariable regression models (23). Race/ethnicity was based on self-identification.…”