Dyslipidemia in Young American Indians: Strong Heart Family Study
Authors: Reese Jessica A. , Roman Mary J. , Deen Jason F. , Ali Tauqeer , Cole Shelley A. , Devereux Richard B. , Fretts Amanda M. , Howard Wm. James , Lee Elisa T. , Malloy Kimberly , Singh Parmanand , Umans Jason G. , Zhang Ying 
Published: June 2023

Background

Although many studies on the association between dyslipidemia and cardiovascular disease (CVD) exist in older adults, data on the association among adolescents and young adults living with disproportionate burden of cardiometabolic disorders are scarce.

Methods

The Strong Heart Family Study (SHFS) is a multi-center, family-based, prospective cohort study of CVD in American Indians, including 12 communities in central Arizona, southwestern Oklahoma, and the Dakotas. We evaluated SHFS participants, 15-39 years old at the baseline examination in 2001-2003 (n=1,440). Lipids were measured after a 12-hour fast. We used carotid ultrasounds to detect plaque at baseline and follow-up in 2006-2009 (median follow-up=5.5 years). We identified incident CVD events through 2020 with a median follow-up of 18.5 years. We used shared frailty proportional hazards models to assess the association between dyslipidemia and subclinical or clinical CVD, while controlling for covariates.

Results

Baseline dyslipidemia prevalence was 55.2%, 73.6%, and 78.0% for participants 15-19, 20-29, and 30-39 years old, respectively. Approximately 2.8% had LDL-C ≥ 160 mg/dL, which is higher than the recommended threshold for lifestyle or medical interventions in young adults of 20-39 years old. During follow-up, 9.9% had incident plaque (109/1,104 plaque free participants with baseline and follow-up ultrasounds), 11.0% had plaque progression (128/1,165 with both baseline and follow-up ultrasounds), and 9.2% had incident CVD (130/1,416 CVD free participants at baseline). Plaque incidence and progression was higher in participants with total cholesterol ≥200 mg/dL, LDL-C ≥160 mg/dL, or non-HDL-C ≥130 mg/dL, while controlling for covariates. CVD risk was independently associated with LDL-C≥160 mg/dL.

Conclusions

Dyslipidemia is a modifiable risk factor that is associated with both subclinical and clinical CVD even among the younger population of American Indians who have unexpectedly high rates of significant CVD events. Therefore, this population is likely to benefit from a variety of evidence-based interventions including screening, educational, lifestyle and guideline directed medical therapy at an early age.

Clinical Perspective

What is new?

First report of lipid levels and dyslipidemia in American Indians under 40 years old, in a large, prospectively followed, multi-site cohort.

The prevalence of dyslipidemia was 55.2%, 73.6%, and 78.0% for participants 15-19, 20-29, and 30-39 years old, respectively, which was more than twice as high than the general U.S. population in every age group.

Abnormal lipid levels were independently associated with incident plaque, progression of plaque, and the hard clinical end points of cardiovascular disease morbidity and mortality.

What are the clinical implications?

Screening and management of dyslipidemia for the prevention of cardiovascular diseases are needed among adolescents and young adults who are predisposed to high risk of cardiometabolic disorders.

Evidence-based interventions that include cholesterol health education, lifestyle modification, and guideline directed medical therapy may be used in preventing and managing dyslipidemia in the aforementioned population.