Comparison of Risk Scores for the Prediction of Stroke in African Americans: Findings from the Jackson Heart Study

• Published in: The American heart journal 2016-07, Vol.177, p.25-32
• Main Authors: Foraker, Randi E., PhD, MA, FAHA, Greiner, Melissa, MS, Sims, Mario, PhD, Tucker, Katherine L., PhD, Towfighi, Amytis, MD, Bidulescu, Aurelian, MD, PhD, MPH, Shoben, Abigail B., PhD, Smith, Sakima, MD, MPH, Talegawkar, Sameera, PhD, MHSc, Blackshear, Chad, MS, Wang, Wei, PhD, Hardy, N. Chantelle, MPH, O’Brien, Emily, PhD
• Format: Article
• Language: English
• Subjects: Adult; African Americans; Aged; Aged, 80 and over; American Heart Association; Behavior; Black or African American - statistics & numerical data; Body mass index; Cardiovascular; Cardiovascular disease; Cardiovascular Diseases - epidemiology; Cholesterol; Cohort Studies; Colleges & universities; Coronary Disease - epidemiology; Demographics; Diabetes; Family medical history; Fasting; Female; Glucose; Health care; Health risk assessment; Heart attacks; Humans; Incidence; Kaplan-Meier Estimate; Laboratories; Male; Medical records; Middle Aged; Nutrition research; Proportional Hazards Models; Risk Assessment; Risk Factors; Stroke; Stroke - epidemiology; United States; Young Adult
• ISSN: 0002-8703; 1097-6744
• DOI: 10.1016/j.ahj.2016.04.007

Background Evidence from existing cohort studies support the prediction of incident coronary heart disease and stroke using 10-year cardiovascular disease (CVD) risk scores and the American Heart Association/American Stroke Association’s cardiovascular health (CVH) metric. Methods We included all Jackson Heart Study participants with complete scoring information at the baseline study visit (2000–2004) who had no history of stroke (n=4,140). We used Kaplan-Meier methods to calculate the cumulative incidence of stroke, and used Cox models to estimate hazard ratios and 95% confidence intervals for stroke according to CVD risk and CVH score. We compared the discrimination of the two models according to the Harrell c-index, and plotted predicted versus observed stroke risk calibration plots for each of the two models. Results The median age of the African-American participants was 54.5 years, and 65% were female. The cumulative incidence of stroke increased across worsening categories of CVD risk and CVH. A one-unit increase in CVD risk increased the hazard of stroke (1.07, 1.06-1.08), while each one-unit increase in CVH corresponded to a decreased hazard of stroke (0.76, 0.69-0.83). As evidenced by the c-statistics, the CVH model was less discriminating than the CVD risk model (0.59, 0.55-0.64 versus 0.79, 0.76-0.83). Conclusions Both scores were associated with incident stroke in a dose–response fashion; however, the CVD risk model was more discriminating than the CVH model. The CVH score may still be preferable for its simplicity in application to broad patient populations and public health efforts.