Anemia and its Relationship w/ Sarcopenia, Physical function and Mortality (Anemia)

Anemia is a common health problem in US older populations and it increases the risk for disability, decline in physical performance, low muscle strength, and premature death in the elderly. A recent study from NHANES III reported the prevalence rate of anemia being larger than 10% in the US population over age 65. The prevalence of anemia varies by ethnicity, suggesting significant health disparities in minorities, especially in the non-Hispanic black population. There is an urgent need to study the patterns and health consequences of anemia in older people from different ethnic groups. In this study, a large (N >160,000) multiethnic (non-Hispanic white, Hispanic, African American, Native American, Asian/Pacific Islander) cohort from the US nationwide Women’s Health Initiative (WHI) study will be used to achieve the following specific aims: 1) examine associations of anemia with skeletal muscle loss (sarcopenia) among WHI women with baseline and prospective measurements of body composition using dual-energy x-ray absorptiometry; 2) determine the association between anemia and risk of death over 10 years of follow-up in postmenopausal women overall, and by race-ethnicity; 3) determine associations between anemia and changes in physical function over 9 years of follow-up in postmenopausal women overall, and by race-ethnicity; 4) determine the frequency of anemia and anemia subtypes by morphologic categories according to race-ethnicity in the diverse population of postmenopausal women enrolled in the WHI. A number of secondary aims are also proposed to study the association of anemia with other health outcomes. This study will use existing data in the WHI from 40 WHI clinical centers. Additional data entering (including MCV, MCH, MCHC and RBC from existing files) and data merging (body composition measurements) will be conducted in the WHI DXA cohort from Arizona, Birmingham and Pittsburgh. Multivariate analyses will be conducted to test the primary hypotheses. The WHI provides a unique and invaluable resource for answering the research questions proposed above. In additional to the large longitudinal cohort and enormous numbers of covariates, the WHI is the only study in the nation that has prospective body composition data as well as anemia measures in multiethnic groups of older women. This study has a great potential to provide new and critical evidence that are needed for preventing and managing anemia in older women from different ethnic backgrounds.

PI: Beth Lewis, MD MSPH

Funding Source: University of Arizona (Tuscon)