Sistas Inspiring Sistas Through Activity and Support (SISTAS): Study Design and Demographics of Participants

Meal timing, distribution of macronutrients, and inflammation among African-American women: A cross-sectional study

Chronic low-grade inflammation is an underlying risk factor for numerous chronic diseases, including cancer. Eating earlier in the day has been associated with a reduction in levels of inflammatory markers and inflammation-related health outcomes (e.g., obesity, metabolic disorders). This cross-sectional study of 249 obese African-American women examined the effect of various mealtime-related factors associated with macronutrient consumption in relation to chronic inflammation and Breast Imaging Reporting and Data System (BI-RAD) readings. During 2011 and 2013, a single 24-hour dietary recall was administered, blood samples were assayed for c-reactive protein (CRP) and interleukin-6 (IL-6), and BI-RAD ratings were assessed to determine the influence of mealtime on chronic inflammation and breast cancer risk score. Multiple linear and logistic regression models were used to assess these relationships. Higher carbohydrate consumption at breakfast was associated with a significantly lower CRP vs. higher carbohydrate consumption at dinner (6.99, vs. 9.56 mg/L, respectively, p = .03). Additionally, every 1-unit increase in percent energy consumed after 5PM resulted in a BI-RAD reading indicating a possibly suspicious abnormality (OR: 1.053, 95% CI: 1.003-1.105), suggesting an increase in breast cancer risk. Timing of energy and macronutrient intake may have important implications for reducing the risk of diseases associated with chronic inflammation.

Recruitment and Retention of Healthy, Postmenopausal Women of African and European Ancestry: Results from a Dietary Intervention with Repeated Biospecimen Collections

Recruitment of minority participants to clinical trials, especially studies without therapeutic intent, has been historically challenging. This study describes barriers to and successes of recruitment and retention strategies to dietary studies. A flaxseed study was conducted in healthy, postmenopausal women of African ancestry (AA) and European ancestry (EA) to assess associations between gut microbial community composition and host metabolism (NCT01698294). To ensure equitable participation by AA and EA women, multiple forms of recruitment were utilized, including advertisements, posters, e-mail, word of mouth, and community outreach. Successful recruitment and retention of AA women to the intervention depended upon the specific methods used. AA women compared with EA women were more likely to respond to direct recruitment and community-based methods, rather than general advertisements. However, once women expressed interest, similar rates of consent were observed for AA and EA women (AA and EA: 51.6% vs. 55.7%, respectively; P > 0.05), supporting the willingness of minority populations to participate in clinical research. Retention, however, was lower among AA compared with EA women (AA and EA: 57.6% vs. 80.9%, respectively; P < 0.01), which may be related to multiple factors, including health reasons, intolerance to flaxseed, noncompliance with study requirements, time constraints, and nonspecified personal reasons. This study confirms the utility of direct community-based strategies for recruitment of diverse populations into nontherapeutic dietary intervention studies. The methods used successfully identified eligible women who expressed willingness to consent to the trial and were able to achieve >70% of recruitment goals for AA women. Future efforts are warranted to improve retention to complex studies. This trial was registered at www.clinicaltrials.gov as NCT01698294.

Temporal changes in allostatic load patterns by age, race/ethnicity, and gender among the US adult population; 1988-2018

The objective of this study is to provide an assessment of allostatic load (AL) burden among US adults across race/ethnicity, gender, and age groups over a 30-year time period. We analyzed data from 50,671 participants of the National Health and Nutrition Examination Survey (NHANES) years 1988 through 2018. AL score was defined as the sum total for abnormal measures of the following components: serum albumin, body mass index, serum C - reactive protein, serum creatinine, diastolic blood pressure, glycated hemoglobin, systolic blood pressure, total cholesterol, and serum triglycerides. We performed modified Poisson regression to estimate the adjusted Relative Risks (aRRs) of allostatic load, and generalized linear models to determine adjusted mean differences accounting for NHANES sampling weights. Among US adults aged 18 or older, the prevalence of high AL increased by more than 45% from 1988 to 1991 to 2015-2018, from 33.5% to 48.6%. By the latest period, 2015-2018, Non-Hispanic Black women (aRR: 1.292; 95% CI: 1.290-1.293) and Latina women (aRR: 1.266; 95% CI: 1.265-1.267) had higher risks of AL than non-Hispanic White women. Similar trends were observed among men. Age-adjusted mean AL score among NH-Black and Latinx adults was higher than for NH-Whites of up to a decade older regardless of gender. From 1988 through 2018, Adults aged 40 years old and older had over 2-fold increased risks of high AL when compared to adults 18-29 years old. After 30-years of collective data, racial disparities in allostatic load persist for NH-Black and Latinx adults.

The impact of a randomized dietary and physical activity intervention on chronic inflammation among obese African-American women

Lifestyle interventions may reduce inflammation and lower breast cancer (BrCa) risk. This randomized trial assessed the impact of the Sistas Inspiring Sistas Through Activity and Support (SISTAS) study on plasma C-reactive protein (CRP), interleukin-6 (IL-6) and Dietary Inflammatory Index (DII). This unblinded, dietary and physical activity trial was implemented in 337 obese (body mass index [BMI] ≥30 kg/m²) African American (AA) women recruited between 2011 and 2015 in South Carolina through a community-based participatory approach with measurements at baseline, 3 months, and 12 months. Participants were randomized into either intervention (n = 176) or wait-list control group (n = 161). Linear mixed-effect models were used for analyses of CRP and IL-6. Baseline CRP was significantly higher in those with greater obesity, body fat percentage, and waist circumference (all p <.01). No difference was observed between groups for CRP or IL-6 at 3 or 12 months; however, improvements in diet were observed in the intervention group compared to the control group (p = .02) at 3 months but were not sustained at 12 months. Although the intervention was not successful at reducing levels of CRP or IL-6, a significant decrease was observed in DII score for the intervention group, indicating short-term positive dietary change.