PURPOSE The Hispanic Community Health Study (HCHS)/Study of Latinos (SOL) is a comprehensive multi-center community based cohort study of Hispanics/Latinos in the United States. Its rationale, objectives, design and implementation are described in this paper. METHODS The HCHS/SOL will recruit 16,000 men and women who self-identify as Hispanic or Latino, age 18-74 years, from a random sample of households in defined communities in the Bronx, Chicago, Miami and San Diego. The sites were selected so that the overall sample would consist of at least 2000 persons in each of the following origin designations: Mexican, Puerto Rican and Dominican, Cuban, and Central and South American. The study includes research in the prevalence of and risk factors for heart, lung, blood and sleep disorders, kidney and liver function, diabetes, cognitive function, dental conditions, and hearing disorders. CONCLUSIONS The HCHS/SOL will 1) characterize the health status and disease burden in the largest minority population in the U.S; 2) describe the positive and negative consequences of immigration and acculturation of Hispanics/Latinos to the mainstream U.S. life-styles, environment and health care opportunities; and 3) identify likely causal factors of many diseases in a population with diverse environmental exposures, genetic backgrounds and early life experiences.

PURPOSE The Hispanic Community Health Study (HCHS)/Study of Latinos (SOL) is a multi-center, community based cohort study of Hispanic/Latino adults in the United States. A diverse participant sample is required that is both representative of the target population and likely to remain engaged throughout follow-up. The choice of sample design, its rationale, and benefits and challenges of design decisions are described in this paper. METHODS The study design calls for recruitment and follow-up of a cohort of 16,000 Hispanics/Latinos aged 18-74 years, with 62.5% (10,000) over 44 years of age and adequate subgroup sample sizes to support inference by Hispanic/Latino background. Participants are recruited in community areas surrounding four field centers in the Bronx, Chicago, Miami, and San Diego. A two-stage area probability sample of households is selected with stratification and over-sampling incorporated at each stage to provide a broadly diverse sample, offer efficiencies in field operations, and ensure that the target age distribution is obtained. CONCLUSIONS Embedding probability sampling within this traditional, multi-site cohort study design enables competing research objectives to be met. However, the use of probability sampling requires developing solutions to some unique challenges in both sample selection and recruitment, as described here.

OBJECTIVEApproximately one-third of the adult U.S. population has the metabolic syndrome. Its prevalence is the highest among Hispanic adults, but variation by Hispanic/Latino background is unknown. Our objective was to quantify the prevalence of the metabolic syndrome among men and women 18–74 years of age of diverse Hispanic/Latino background.RESEARCH DESIGN AND METHODSTwo-stage area probability sample of households in four U.S. locales, yielding 16,319 adults (52% women) who self-identified as Cuban, Dominican, Mexican, Puerto Rican, Central American, or South American. The metabolic syndrome was defined according to the American Heart Association/National Heart, Lung, and Blood Institute 2009 Joint Scientific Statement. The main outcome measures were age-standardized prevalence of the metabolic syndrome per the harmonized American Heart Association/National Heart, Lung, and Blood Institute definition and its component abnormalities.RESULTSThe metabolic syndrome was present in 36% of women and 34% of men. Differences in the age-standardized prevalence were seen by age, sex, and Hispanic/Latino background. The prevalence of the metabolic syndrome among those 18–44, 45–64, and 65–74 years of age was 23%, 50%, and 62%, respectively, among women; and 25%, 43%, and 55%, respectively, among men. Among women, the metabolic syndrome prevalence ranged from 27% in South Americans to 41% in Puerto Ricans. Among men, prevalences ranged from 27% in South Americans to 35% in Cubans. In those with the metabolic syndrome, abdominal obesity was present in 96% of the women compared with 73% of the men; more men (73%) than women (62%) had hyperglycemia.CONCLUSIONSThe burden of cardiometabolic abnormalities is high in Hispanic/Latinos but varies by age, sex, and Hispanic/Latino background. Hispanics/Latinos are thus at increased, but modifiable, predicted lifetime risk of diabetes and its cardiovascular sequelae.