Racially Conscious Cancer Screening Guidelines: A Path Towards Culturally Competent Science.

OBJECTIVE: To review the racial composition of the study populations that the current USPSTF screening guidelines for lung, breast, and colorectal cancer are based on, and the effects of their application across non-white individuals. SUMMARY OF BACKGROUND DATA: USPSTF guidelines commonly become the basis for establishing standards of care, yet providers are often unaware of the racial composition of the study populations they are based on. METHODS: We accessed the USPSTF screening guidelines for lung, breast, and colorectal cancer via their website, and reviewed all referenced publications for randomized controlled trials (RCTs), focusing on the racial composition of their study populations. We then used PubMed to identify publications addressing the generalizability of such guidelines across non-white individuals. Lastly, we reviewed all guidelines published by non-USPSTF organizations to identify the availability of race-specific recommendations. RESULTS: Most RCTs used as basis for the current USPSTF guidelines either did not report race, or enrolled cohorts that were not representative of the U.S. population. Several studies were identified demonstrating the broad application of such guidelines across non-white individuals can lead to underdiagnosis and higher levels of advanced disease. Nearly all guideline-issuing bodies fail to provide race-specific recommendations, despite often acknowledging increased disease burden among non-whites. CONCLUSION: Concerted efforts to overcome limitations in the generalizability of RCTs are required to provide screening guidelines that are truly applicable to non-white populations. Broader policy changes to improve the pipeline for minority populations into science and medicine are needed to address the ongoing lack of diversity in these fields.

Measurements of serum free cortisol in critically ill patients.

BACKGROUND: Because more than 90 percent of circulating cortisol in human serum is protein-bound, changes in the binding proteins can alter measured serum total cortisol concentrations without influencing free concentrations of this hormone. We investigated the effect of decreased amounts of cortisol-binding proteins on serum total and free cortisol concentrations during critical illness, when glucocorticoid secretion is maximally stimulated. METHODS: Base-line serum total cortisol, cosyntropin-stimulated serum total cortisol, aldosterone, and free cortisol concentrations were measured in 66 critically ill patients and 33 healthy volunteers in groups that were similar with regard to sex and age. Of the 66 patients, 36 had hypoproteinemia (albumin concentration, 2.5 g per deciliter or less), and 30 had near-normal serum albumin concentrations (above 2.5 g per deciliter). RESULTS: Base-line and cosyntropin-stimulated serum total cortisol concentrations were lower in the patients with hypoproteinemia than in those with near-normal serum albumin concentrations (P<0.001). However, the mean (+/-SD) base-line serum free cortisol concentrations were similar in the two groups of patients (5.1+/-4.1 and 5.2+/-3.5 microg per deciliter [140.7+/-113.1 and 143.5+/-96.6 nmol per liter]) and were several times higher than the values in controls (0.6+/-0.3 microg per deciliter [16.6+/-8.3 nmol per liter], P<0.001 for both comparisons). Cosyntropin-stimulated serum total cortisol concentrations were subnormal (18.5 microg per deciliter [510.4 nmol per liter] or less) in 14 of the patients, all of whom had hypoproteinemia. In all 66 patients, including these 14 who had hypoproteinemia, the base-line and cosyntropin-stimulated serum free cortisol concentrations were high-normal or elevated. CONCLUSIONS: During critical illness, glucocorticoid secretion markedly increases, but the increase is not discernible when only the serum total cortisol concentration is measured. In this study, nearly 40 percent of critically ill patients with hypoproteinemia had subnormal serum total cortisol concentrations, even though their adrenal function was normal. Measuring serum free cortisol concentrations in critically ill patients with hypoproteinemia may help prevent the unnecessary use of glucocorticoid therapy.