Physical Function and Strength in Relation to Inflammation in Older Adults with Obesity and Increased Cardiometabolic Risk.

BACKGROUND: Inflammation is implicated in functional decline and the development of disability in aging. This study aimed to investigate the association of inflammation with physical function and muscle strength in older adults with obesity and increased cardiometabolic risk. DESIGN: In baseline assessments from the CROSSROADS randomized controlled trial, serum interleukin-6 (IL-6), tumor necrosis factor-α (TNFα) and C-reactive protein (hs-CRP) were assayed in 163 older adults (37% males, 24% African American, BMI 34±3, age 70±5yrs) with hypertension, dyslipidemia and/or diabetes. Physical function was assessed by six-minute walk test (6MWT), chair sit-and-reach (CSR), hand-grip and knee-extension strength; specific-strength as muscle strength/mass ratio. Analyses included ANCOVA and multiple linear regression adjusted for thigh skeletal muscle (MRI), arm lean mass (DXA) and moderate-to-vigorous intensity physical activity (MVPA; accelerometry). RESULTS: Higher hs-CRP (p<0.01) and IL-6 (p=0.07) were associated with lower 6MWT and CSR, respectively. A composite inflammation score combining all 3 inflammatory markers showed the strongest inverse association with 6MWT (p<0.01). MVPA moderated associations such that amongst participants who engaged in low MVPA, 6MWT distances and CSR scores were significantly lower in those with high IL-6 and TNFα (p<0.05), respectively. In participants with high MVPA, higher hs-CRP (p<0.05) and TNFα (p=0.07) were associated with poorer upper-extremity specific-strength. CONCLUSIONS: Chronic inflammation was associated with poorer physical function and specific strength in older adults with obesity and increased cardiometabolic risk. This association was strongest in participants with multiple elevated inflammatory markers. Physical activity levels below current recommendations mitigated the deleterious effects of inflammation on lower body mobility, underscoring the benefits of exercise for preserving physical function with age.

Weight loss and improved metabolic outcomes amongst rural African American women in the Deep South: six-month outcomes from a community-based randomized trial.

BACKGROUND: Obesity is highly prevalent in African American women, especially those in the rural southern USA, resulting in persistent health disparities. OBJECTIVE: To test the effectiveness of an evidence-based behavioural weight loss intervention delivered by community health advisors to African American women in the rural south. DESIGN AND METHODS: Overweight or obese African American women (30-70 years) from eight counties in Mississippi and Alabama participated in a 24-month randomized controlled trial of an evidence-based behavioural weight loss programme augmented with community strategies to support healthy lifestyles (Weight Loss Plus, N = 154) compared to the weight loss programme alone (Weight Loss Only, N = 255). This study reports on 6-month outcomes on primary (weight change) and secondary (waist circumference, blood pressure, lipids, fasting blood glucose) outcomes, coinciding with the completion of the intensive weight loss phase. RESULTS: Weight Loss Only participants lost an average of 2.2 kg (P < 0.001). Weight Loss Plus participants lost an average of 3.2 kg (P < 0.001). The proportion of the total sample that lost at least 5% of their body weight was 27.1% with no difference between treatment groups. Similarly, we observed statistically significant reductions in blood pressure, waist circumference and triglycerides in each treatment group, with no statistical differences between groups. CONCLUSION: Trained lay health staff and volunteers from the rural southern USA were able to deliver a translation of a high-intensity behavioural intervention targeted to African American women, resulting in clinically meaningful weight loss and improvement in other metabolic outcomes in a significant proportion of participants.

Psychosocial predictors of weight loss by race and sex.

This paper examined the psychosocial predictors of weight loss among race and sex subgroups. Analyses included overweight and obese participants from the PREMIER study, a previously published randomized trial that examined the effects of two multi-component lifestyle interventions on blood pressure among pre-hypertensive and stage 1 hypertensive adults. Both intervention conditions received behavioural recommendations for weight loss and group sessions. Weight and psychosocial measures of self-efficacy and social support for diet and exercise were assessed at baseline and at 6 months. There were 157 African-American (AA) women, 46 AA men, 203 non-AA women and 182 non-AA men with an average age of 50 years and average body mass index of 34 at baseline. Multiple predictor regression models were performed individually by race and sex subgroup. Among AA women, increases in diet self-efficacy were associated with weight loss. Among AA men, increases in diet-related social support and self-efficacy, along with increases in family support to exercise, were associated with weight loss (all Ps <0.05). Among non-AA women, increases in friends' support to exercise and exercise-related self-efficacy were associated with weight loss, and among non-AA men only increases in diet self-efficacy were associated with weight loss (all Ps <0.05). These results emphasize the need for targeted interventions based on race and sex to optimize the impact of lifestyle-based weight loss programmes.

Effect of lifestyle modifications on blood pressure by race, sex, hypertension status, and age.

Recommendations for control of high blood pressure (BP) emphasize lifestyle modification, including weight loss, reduced sodium intake, increased physical activity, and limited alcohol consumption. The Dietary Approaches to Stop Hypertension (DASH) dietary pattern also lowers BP. The PREMIER randomized trial tested multicomponent lifestyle interventions on BP in demographic and clinical subgroups. Participants with above-optimal BP through stage 1 hypertension were randomized to an Advice Only group or one of two behavioural interventions that implement established recommendations (Est) or established recommendations plus DASH diet (Est plus DASH). The primary outcome was change in systolic BP at 6 months. The study population was 810 individuals with an average age of 50 years, 62% women, 34% African American (AA), 95% overweight/obese, and 38% hypertensive. Participants in all the three groups made lifestyle changes. Mean net reductions in systolic (S) BP in the Est intervention were 1.2 mmHg in AA women, 6.0 in AA men, 4.5 in non-AA women, and 4.2 in non-AA men. The mean effects of the Est Plus DASH intervention were 2.1, 4.6, 4.2, and 5.7 mmHg in the four race-sex subgroups, respectively. BP changes were consistently greater in hypertensives than in nonhypertensives, although interaction tests were nonsignificant. The Est intervention caused statistically significant BP reductions in individuals over and under age 50. The Est Plus DASH intervention lowered BP in both age groups, and significantly more so in older individuals. In conclusion, diverse groups of people can adopt multiple lifestyle changes that can lead to improved BP control and reduced CVD risk.

Angiotensinogen genotype and blood pressure response in the Dietary Approaches to Stop Hypertension (DASH) study.

OBJECTIVE: To determine the relationship between angiotensinogen (ANG) genotype and blood pressure response to the dietary patterns of the Dietary Approaches to Stop Hypertension (DASH) trial. The angiotensin converting enzyme (ACE) gene was also tested. DESIGN: The DASH trial was a randomized outpatient feeding study comparing the effects on blood pressure (BP) of three dietary patterns: a control diet, similar to typical American intake; a 'fruits and vegetables' diet (F/V) that is rich in fruits and vegetables but otherwise resembles the control diet; and the DASH diet that is reduced in fats and that emphasizes fruits, vegetables and low-fat dairy products. Participants' genotype was also determined. SETTING: Four clinical sites. PARTICIPANTS: Adults with above-optimal BP or stage 1 hypertension. INTERVENTION: Participants ate one of the three dietary patterns for 8 weeks. Sodium intake and weight were held constant. In 355 of 459 DASH participants, DNA was extracted from leukocytes and genotyped for the G-6A ANG polymorphism and the D/I ACE polymorphism, by the polymerase chain reaction. MAIN OUTCOMES: Genotype at ANG and ACE loci; BP after 8 weeks of intervention diet. RESULTS: There was no association between ACE genotype and BP response. Associations with ANG polymorphism were significant: net systolic and diastolic BP response to the DASH diet was greatest in individuals with the AA genotype (-6.93/-3.68 mmHg) and least in those with the GG genotype (-2.80/0.20 mmHg). A similar relationship existed for the F/V diet. CONCLUSIONS: ANG genotype is associated with BP response to the DASH diet. The AA genotype confers excess risk of hypertension and is associated with increased responsiveness to diet.

Culturally-sensitive weight loss program produces significant reduction in weight, blood pressure, and cholesterol in eight weeks.

Dietary and behavioral needs of special populations are rarely considered in traditional weight loss programs. This study assessed the impact of culturally-sensitive modifications to the Duke University Rice Diet weight loss program for African-American dieters. The study was a randomized modified cross-over study in which volunteers received either early or delayed weight loss intervention. Final outcomes were measured at 8 weeks. At the onset of the study, there were 56 African American participants, however, only 44 (79%) completed the study. The eight-week intervention was a modified 1000-calorie/day version of the Rice Diet. Modifications to the program included decreased cost, culturally-sensitive recipes, addressing attitudes about exercise, and including family members in weight loss efforts. Average weight loss for subjects completing the program was 14.8 pounds (SD = 6.8 pounds). BMI decreased from 37.8 kg/m2 to 35.3 kg/m2 (p < 0.01). Total cholesterol levels decreased from 199.2 mg/dL to 185.4 mg/dL (p < 0.01); systolic and diastolic blood pressure decreased by 4.3 mmHg (p < 0.01) and 2.4 mmHg (p < 0.05), respectively. The control group showed no significant change in any outcome measures. We found that diet programs can be successfully tailored to incorporate the needs of African-Americans. Most importantly, these dietary program changes can lead to significant improvement in clinical parameters. Additional studies are necessary to determine the permanence of these short-term changes.

The effects of dietary patterns on quality of life: a substudy of the Dietary Approaches to Stop Hypertension trial.

Few studies have examined the effects of dietary changes, particularly modifications of whole dietary patterns, on quality of life. The Dietary Approaches to Stop Hypertension (DASH) trial compared the effects of 3 dietary patterns on blood pressure. In this substudy, we examined the effect of these diets on health-related quality of life. All DASH participants ate a control diet for 3 weeks and then were randomly assigned to continue the control diet, to a fruits and vegetables diet or to a combination diet for 8 weeks. The combination diet emphasized fruits, vegetables, and low-fat dairy products. It included whole grains, poultry, fish, and nuts, and was reduced in fats, red meat, sweets, and sugar-containing beverages. The control diet was similar to typical American intake; the fruits and vegetables diet was rich in fruits and vegetables but was otherwise similar to the control diet. Both the fruits and vegetables diet (P < .001) and the combination diet (P < .001) significantly lowered blood pressure. At the Duke University Medical Center, Durham, NC, site, participants completed the Medical Outcomes Study Short Form-36 questionnaire to assess their health-related quality of life at baseline and at the end of the dietary intervention. Eighty-three participants completed the questionnaires at both time points. In general, health-related quality of life improved in all treatment groups except for the control group in perceptions of change in health, which diminished. In the combination diet group all the subscales were improved or unchanged compared with baseline values. However, only the change in health score improved significantly (P < .05) as compared with that of the control diet group. When all the subscales were summed into a total score, the control diet was associated with mean improvement of 4.0%, the fruits and vegetables diet with 5.0%, and the combination diet with 5.9% from baseline. These data suggest that the fruits and vegetables diet and particularly the combination diet cannot only lower blood pressure, but may also improve the perception of health-related quality of life.