Demographic and health factors associated with enrollment in posttrial studies: the Women's Health Initiative Hormone Therapy Trials.

BACKGROUND: After clinical trials end, continued follow-up of the assembled cohort often is desirable for additional research. Factors influencing participants' decisions to consent to additional follow-up and how these shape posttrial cohorts have not been broadly studied. PURPOSE: We examined how two re-enrollment campaigns and the passage of time altered features of the posttrial cohorts compared with the original Women's Health Initiative (WHI) Hormone Therapy clinical trials. METHODS: We examined associations that markers of sociodemography, health, lifestyle, and on-trial experiences had with re-enrollment and contrasted the characteristics of successive posttrial cohorts with those of the original enrollees. RESULTS: The posttrial enrollment campaigns re-enrolled 81.1% and 82.5% of available women, respectively. Women who re-enrolled tended to have better health characteristics than those not re-enrolled. Compared to women of comparable age in the original cohort, women retained for the second posttrial follow-up less often had a history of cardiovascular disease (odds ratio (OR) = 0.36), hypertension (OR = 0.57), diabetes (OR = 0.59), or measured cognitive deficit (OR = 0.40). These women more often had graduated from high school (OR = 1.72) and had participated in other WHI trials (OR = 1.76). LIMITATIONS: We have examined experience with creating follow-up cohorts from participants in a single study. Thus, our findings may not apply to other cohorts and protocols. CONCLUSIONS: Posttrial enrollment in follow-up studies can be successful; however, the characteristics of the resulting cohort may differ substantially from the originally assembled group of trial participants. Collection during the original trial of potential predictors of differential re-enrollment may strengthen interpretation of findings.

Why African-American women are at greater risk for pregnancy-related death.

PURPOSE: Our study aim was to identify factors that may contribute to the racial disparity in pregnancy-related mortality. METHODS: We examined differences in severity of disease, comorbidities, and receipt of care among 608 (304 African-American and 304 white) consecutive patients of non-Hispanic ethnicity with one of three pregnancy-related morbidities (pregnancy-related hypertension, puerperal infection, and hemorrhage) from hospitals selected at random from a statewide region. RESULTS: African-American women had more severe hypertension, lower hemoglobin concentrations preceding hemorrhage, more antepartum hospital admissions, and a higher rate of obesity. The rate of surgical intervention for hemorrhage was lower among African-Americans, although the severity of hemorrhage did not differ between the two racial groups. More African-American women received eclampsia prophylaxis. After stratifying by severity of hypertension, we found that more African-Americans received antihypertensive therapy. The rate of enrollment for prenatal care was lower in the African-American group. Among women receiving prenatal care, African-American women enrolled significantly later in their pregnancies. CONCLUSIONS: We have identified racial differences in severity of disease, comorbidities, and care status among women with pregnancy-related complications that would place African-Americans at disadvantage to survive pregnancy. These differences are potentially modifiable.