Older men and women respond to local and reflex-mediated heat stress with an attenuated increase in cutaneous vascular conductance (CVC). This study was performed to test the hypothesis that an augmented or sustained noradrenergic vasoconstriction (VC) may play a role in this age-related difference. Fifteen young (22 +/- 1 yr) and 15 older (66 +/- 1 yr) men exercised at 50% peak oxygen uptake in a 36 degrees C environment. Skin perfusion was monitored at two sites on the right forearm by laser-Doppler flowmetry: one site pretreated with bretylium tosylate (BT) to block the local release of norepinephrine and thus VC and an adjacent control site. Blockade of reflex VC was verified during whole body cooling using a water-perfused suit. CVC (perfusion divided by mean arterial pressure) at each site was reported as a percentage of the maximal CVC (%CVCmax) induced at the end of each experiment by prolonged local heating at 42 degrees C. Neither age nor BT affected the %CVCmax (75-86%) attained at high core temperatures. During the early rise phase of CVC, the %CVCmax-change in esophageal temperature (delta T(es)) curve was shifted to the right in the older men (effective delta T(es) associated with 50% CVC response for young, 0.22 +/- 0.04 and 0.39 +/- 0.04 degrees C and for older, 0.73 +/- 0.04 and 0.85 +/- 0.04 degrees C at control and BT sites, respectively). BT had no interactive effect on this age difference, suggesting a lack of involvement of the VC system in the attenuated CVC response of individuals over the age of 60 yr. Additionally, increases in skin vascular conductance were quantitatively compared by measuring increases in total forearm vascular conductance (FVC, restricted to the forearm skin under these conditions). After the initial approximately 0.2 degrees C increase in T(es), FVC was 40-50% lower in the older men (P < 0.01) for the remainder of the exercise. Decreased active vasodilator sensitivity to increasing core temperature, coupled with structural limitations to vasodilation, appears to limit the cutaneous vascular response to exertional heat stress in older subjects.

This investigation examined effects of chronic (>/=2 yr) hormone replacement therapy (HRT), both estrogen replacement therapy (ERT) and estrogen plus progesterone therapy (E+P), on core temperature and skin blood flow responses of postmenopausal women. Twenty-five postmenopausal women [9 not on HRT (NO), 8 on ERT, 8 on E+P] exercised on a cycle ergometer for 1 h at an ambient temperature of 36 degrees C. Cutaneous vascular conductance (CVC) was monitored by laser-Doppler flowmetry, and forearm vascular conductance (FVC) was measured by using venous occlusion plethysmography. Iontophoresis of bretylium tosylate was performed before exercise to block local vasoconstrictor (VC) activity at one skin site on the forearm. Rectal temperature (Tre) was approximately 0.5 degrees C lower for the ERT group (P < 0.01) compared with E+P and NO groups at rest and throughout exercise. FVC: mean body temperature (Tb) and CVC: Tb curves were shifted approximately 0.5 degrees C leftward for the ERT group (P < 0.0001). Baseline CVC was significantly higher in the ERT group (P < 0.05), but there was no interaction between bretylium treatment and groups once exercise was initiated. These results suggest that 1) chronic ERT likely acts centrally to decrease Tre, 2) ERT lowers the Tre at which heat-loss effector mechanisms are initiated, primarily by actions on active cutaneous vasodilation, and 3) addition of exogenous progestins in HRT effectively blocks these effects.

Factors contributing to racial inequities in outcomes from coronavirus disease 2019 (COVID-19) remain poorly understood. We compared by race the risk of 4 COVID-19 health outcomes––maximum length of hospital stay (LOS), invasive ventilation, hospitalization exceeding 24 h, and death––stratified by Elixhauser comorbidity index (ECI) ranking. Outcomes and ECI scores were constructed from retrospective data obtained from the Cerner COVID-19 De-Identified Data cohort. We hypothesized that racial disparities in COVID-19 outcomes would exist despite comparable ECI scores among non-Hispanic (NH) Blacks, Hispanics, American Indians/Alaska Natives (AI/ANs), and NH Whites. Compared with NH Whites, NH Blacks had longer hospital LOS, higher rates of ventilator dependence, and a higher mortality rate; AI/ANs, higher odds of hospitalization for ECI = 0 but lower for ECI ≥ 5, longer LOS for ECI = 0, a higher risk of death across all ECI categories except ECI ≥ 5, and higher odds of ventilator dependence; Hispanics, a lower risk of death across all ECI categories except ECI = 0, lower odds of hospitalization, shorter LOS for ECI ≥ 5, and higher odds of ventilator dependence for ECI = 0 but lower for ECI = 1–4. Our findings contest arguments that higher comorbidity levels explain elevated COVID-19 death rates among NH Blacks and AI/ANs compared with Hispanics and NH Whites.

Standardized programming for individuals with sickle cell disease (SCD) transitioning from pediatric to adult-centered care does not currently exist, resulting in high rates of mortality and morbidity. This scoping review examines and evaluates the current literature on SCD transition programs and interventions. Eligible studies described an existing program for individuals with SCD aged 12-29 years preparing to transition.The Evidence Project risk-of-bias tool was used to assess article quality. We identified 30 eligible articles, of which, only two were randomized controlled trials. Many studies have incomplete reports of feasibility information, such as completion rates, patient characteristics, and attrition; all studies were limited to a single institution; and most studies were rated high for risk of bias. Progress has been made in designing and gathering initial evaluation data for SCD transition programs; however, there is a need for higher quality studies, consistent assessment, and better dissemination of programs.

PURPOSE: Racial and ethnic minorities remain underrepresented in research and clinical trials. Better understanding of the components of effective minority recruitment into research studies is critical to understanding and reducing health disparities. Research on recruitment strategies for cancer-specific research—including colorectal cancer (CRC)—among African American men is particularly limited. We present an instrumental exploratory case study examining successful and unsuccessful strategies for recruiting African American men into focus groups centered on identifying barriers to and facilitators of CRC screening completion. METHODS: The parent qualitative study was designed to explore the social determinants of CRC screening uptake among African American men 45-75 years of age. Recruitment procedures made use of community-based participatory research strategies combined with built community relationships, including the use of trusted community members, culturally tailored marketing materials, and incentives. RESULTS: Community involvement and culturally tailored marketing materials facilitated recruitment. Barriers to recruitment included limited access to public spaces, transportation difficulties, and medical mistrust leading to reluctance to participate. CONCLUSION: The use of strategies such as prioritizing community relationship building, partnering with community leaders and gatekeepers, and using culturally tailored marketing materials can successfully overcome barriers to the recruitment of African American men into medical research studies. To improve participation and recruitment rates among racial and ethnic minorities in cancer-focused research studies, future researchers and clinical trial investigators should aim to broaden recruitment, strengthen community ties, offer incentives, and use multifaceted approaches to address specific deterrents such as medical mistrust and economic barriers.