Faculty Bibliography

OBJECTIVES: This study sought to improve global vascular risk prediction with behavioral and anthropometric factors. BACKGROUND: Few cardiovascular risk models are designed to predict the global vascular risk of myocardial infarction, stroke, or vascular death in multiethnic individuals, and existing schemes do not fully include behavioral risk factors. METHODS: A randomly derived, population-based, prospective cohort of 2,737 community participants free of stroke and coronary artery disease was followed up annually for a median of 9.0 years in the NOMAS (Northern Manhattan Study) (mean age 69 years, 63.2% women, 52.7% Hispanic, 24.9% African American, and 19.9% white). A global vascular risk score (GVRS) predictive of stroke, myocardial infarction, or vascular death was developed by adding variables to the traditional Framingham cardiovascular variables based on the likelihood ratio criteria. Model utility was assessed through receiver-operating characteristics, calibration, and effect on reclassification of subjects. RESULTS: Variables that significantly added to the traditional Framingham profile included waist circumference, alcohol consumption, and physical activity. Continuous measures for blood pressure and fasting blood sugar were used instead of hypertension and diabetes. Ten-year event-free probabilities were 0.95 for the first quartile of GVRS, 0.89 for the second quartile, 0.79 for the third quartile, and 0.56 for the fourth quartile. The addition of behavioral factors in our model improved prediction of 10-year event rates compared with a model restricted to the traditional variables. CONCLUSIONS: A GVRS that combines traditional, behavioral, and anthropometric risk factors; uses continuous variables for physiological parameters; and is applicable to nonwhite subjects could improve primary prevention strategies.

Cognitive impairment and chronic kidney disease (CKD) will become increasingly prevalent in the aging US population. Although evidence exists that CKD is a risk factor for cognitive decline, longitudinal studies are limited and largely have excluded ethnically diverse populations. The Northern Manhattan Study includes a population-based, prospective, stroke-free cohort. We assessed global cognitive function annually using the modified Telephone Interview for Cognitive Status (TICS-m) and estimated kidney function using Cockcroft-Gault creatinine clearance (CCl), Modification of Diet in Renal Disease estimated GFR (eGFR), and serum creatinine (sCr). We examined the association between CKD and change in TICS-m scores over time, adjusting for sociodemographic and vascular risk factors. Of 2172 subjects (mean age 71.5 yr, mean follow-up 2.9 yr), 59% were Hispanic, 20% were black, and 63% were women. Participants with a CCl <60 ml/min and those with a CCl between 60 and 90 ml/min performed significantly worse on the TICS-m over time than those with a CCl >90 ml/min, adjusting for potential confounders. Our results were similar when we used eGFR or sCr to estimate kidney function. In conclusion, decreased kidney function associates with greater cognitive decline, even in those with mild CKD. Kidney disease may represent a novel mechanism leading to cognitive impairment and a target for early intervention.

BACKGROUND AND PURPOSE: The objective of this study was to determine the relationship between chronic kidney disease (CKD), race-ethnicity, and vascular outcomes. METHODS: A prospective, multiracial cohort of 3298 stroke-free subjects with 6.5 years of mean follow-up time for vascular outcomes (stroke, myocardial infarction, vascular death) was used. Kidney function was estimated using serum creatinine and Cockcroft-Gault formula. Cox proportional hazards models were fitted to evaluate the relationship between kidney function and vascular outcomes. RESULTS: In multivariate analysis, Cockcroft-Gault formula between 15 and 59 mL/min was associated with a significant 43% increased stroke risk in the overall cohort. Blacks with Cockcroft-Gault formula between 15 and 59 mL/min had significantly increased risk of both stroke (hazard ratio, 2.65; 95% CI, 1.47 to 4.77) and combined vascular outcomes (hazard ratio, 1.59; 95% CI, 1.10-2.92). CONCLUSIONS: Chronic kidney disease is a significant risk factor for stroke and combined vascular events, especially in blacks.

BACKGROUND AND PURPOSE/OBJECTIVE:White matter hyperintensities have been associated with increased risk of stroke, cognitive decline, and dementia. Chronic kidney disease is a risk factor for vascular disease and has been associated with inflammation and endothelial dysfunction, which have been implicated in the pathogenesis of white matter hyperintensities. Few studies have explored the relationship between chronic kidney disease and white matter hyperintensities. METHODS:The Northern Manhattan Study is a prospective, community-based cohort of which a subset of stroke-free participants underwent MRIs. MRIs were analyzed quantitatively for white matter hyperintensities volume, which was log-transformed to yield a normal distribution (log-white matter hyperintensity volume). Kidney function was modeled using serum creatinine, the Cockcroft-Gault formula for creatinine clearance, and the Modification of Diet in Renal Disease formula for estimated glomerular filtration rate. Creatinine clearance and estimated glomerular filtration rate were trichotomized to 15 to 60 mL/min, 60 to 90 mL/min, and >90 mL/min (reference). Linear regression was used to measure the association between kidney function and log-white matter hyperintensity volume adjusting for age, gender, race-ethnicity, education, cardiac disease, diabetes, homocysteine, and hypertension. RESULTS:Baseline data were available on 615 subjects (mean age 70 years, 60% women, 18% whites, 21% blacks, 62% Hispanics). In multivariate analysis, creatinine clearance 15 to 60 mL/min was associated with increased log-white matter hyperintensity volume (beta 0.322; 95% CI, 0.095 to 0.550) as was estimated glomerular filtration rate 15 to 60 mL/min (beta 0.322; 95% CI, 0.080 to 0.564). Serum creatinine, per 1-mg/dL increase, was also positively associated with log-white matter hyperintensity volume (beta 1.479; 95% CI, 1.067 to 2.050). CONCLUSIONS:The association between moderate-severe chronic kidney disease and white matter hyperintensity volume highlights the growing importance of kidney disease as a possible determinant of cerebrovascular disease and/or as a marker of microangiopathy.