Current export research activities

Project 1: Long term efficacy and safety of the Atkins Diet (P1: Foster, NIH ROl ATO11O3-0; 03/02 - 02/07):

The specific aim is to: assess the short-term and long-term clinical effects of the Atkins diet in 360 obese men and women. Participants will be randomized to the Atkins diet (low-carbohydrate, unlimited fat and protein) or a conventional USDA diet (high-carbohydrate, low-fat). The effects of each dietary approach on changes in: 1) weight and body composition; 2) metabolic and organ function; and 3) exercise tolerance will be evaluated.

Project 2: Sleep apnea in Look AHEAD participants (P1: Foster, ROl HL70301; 07/01 - 06/06):

The research proposed in this application will assess the effects of weight loss on sleep disordered breathing in 120 obese, type 2 diabetics with obstructive sleep apnea (OSA) (RDI> 15) who are randomly assigned to either. weight loss (n=60) or usual care (n=60) treatments within the context of the Look AHEAD study. Home polysomnography studies will be performed before treatment and at 1 and 2 years. Among the 60 weight loss subjects, the investigators will assess the relative importance of changes in neck and abdominal fat in explaining the variability of changes in sleep disordered breathing after weight loss. Finally, the investigators will examine the relationship between changes in sleep-disordered breathing and changes in blood pressure after weight loss in the 60 weight loss participants. Specifically, this research will: 1) determine the efficacy of a weight loss program in reducing sleep disordered breathing in obese type 2 diabetics; 2) identify sources of variability in sleep disordered breathing associated with weight loss; and 3) examine the role of sleep disordered breathing in mediating changes in blood pressure associated with weight loss.

Project 3: Barriers to Physician Recommendation of Colorectal Cancer Screening (P1: Guerra; NCI KOl CA 97925; 10/02-10/07):

Physician recommendation is one of the strongest predictors of patient compliance with colorectal cancer screening. It is unclear why, despite the evidence that supports colorectal cancer screening and the existence of g idelines from multiple organizations recommending screening, physicians continue to underrecommend screening. The proposed two-phase research program will further understanding of the barriers and facilitators of physician recommendation of colorectal cancer screening. The proposed research project has three specific aims: 1) To identify the reasons why primary care physicians do and do not recommend colorectal cancer screening (phase 1); 2) To describe the reported frequency and relative importance of barriers and facilitators to physician recommendation of colorectal cancer screening in a nation-wide sample of primary care physicians (phase 2); and 3) To evaluate the impact of various levels of barriers and facilitators on p propensity to recommend colorectal cancer screening (phase 2).

Project 4: Weight management skills in African American outpatients (P1: Kumanyika;' ROl HL069400- 01; 7/02 - 06/06):

This study will examine the effectiveness of social support approaches, particularly involvement of family members and friends, in facilitating weight loss and related dietary and physical activity changes in African Americans. Men and women will be recruited from an urban, university health system and the surrounding community. Women and men eligible as "index" participants will be African Americans ages 35 to 70 years (n=128) with a body mass index (BMI) of 27 to 50 kg/rn and at least one obesity-related co morbidity or clinical CVD risk factor. Index participants will be encouraged but not required to name 1 or 2 family member or friend co-participants. Co-participants (n=128 to 256) will be eligible if they are aged 16 to 70 years and have a BMI in the same range as index participants by adult or adolescent BMI criteria. All index participants will receive the same group, behavioral counseling program supplemented with individual counseling. Index participants who name co-participants will be randomly assigned in a 1:1 ratio to Group A, direct involvement of family members and.friends, or Group B, indirect involvement of family members and friends. In Group A, both index and co-participants will be included in all counseling sessions. In Group B, co participants will not be included in group counseling sessions but will be provided self-help materials and invited to accompany index participants to individual counseling sessions. Index participants who do not identify co-participants (n=64) be randomly assigned in a 1:1 ratio to Group C, assigned to teams with other index participants, or Group D, not so assigned. Primary hypotheses are that weight loss from 0 to 12 months, 0 to 24 months, and weight maintenance from 12 to 24 months will be greater in Group A vs. Group B and in Group C vs. Group D. Secondary analyses will compare the respective treatment and control groups on diet, physical activity, and clinical CYD risk factor changes and will assess predictors of outcomes and cost- effectiveness.

Project 5: Bacterial vaginosis and pregnancy outcomes in low income women (P1: Nelson ROl HD38856, 04/0 1 - 03/06):

Bacterial vaginosis (BV) is extremely prevalent among low-income, urban pregnant women. The current standard of medical care does not involve screening pregnant women for BV unless clinical symptoms are reported; however, the majority of pregnant women with BV are asymptomatic. A number of studies have found associations between BY and late pregnancy outcomes; such as, preterm labor, premature rupture of membrane, chorioamnionitis, and low birth weight. The impact of BV on the risk for spontaneous abortion (SAB) is unclear. In the proposed prospective cohort study, all women will be screened for BV early in pregnancy regardless of symptoms. The specific aims of this study are to: 1) characterize the prevalence and predictors of BV in women early in pregnancy and 2) evaluate whether BV during pregnancy is an important, independent predictor of SAB. Women attending their first clinical prenatal care visit at the Hospital of the University of Pennsylvania Obstetric Clinic with a pregnancy of 12 weeks gestation or less as determined by last menstrual period will be recruited. We will screen all women for bacterial vaginosis and follow-up through 22 weeks gestation to identify women experiencing a spontaneous abortion. We will enroll 2200 women over a three year period and compare SAB rates for the estimated 400 women found to test positive for BV (20% of patients) and the 1600 women found to test negative for BV. Baseline data collection will be standardized and include a structured in-person interview, a vaginal smear used to detect BV, and urine analysis to determine alcohol, cocaine and cotinine. Follow-up telephone interviews will be conducted at 22 weeks gestation to determine the status of pregnancy (SAB vs. non-SAB) and BV diagnosis and treatment. Pregnancy outcome status will also be ascertained through ongoing review of medical records, pathology logs and birth certificates.

Project 6: Energy balance in children with Down's Syndrome (P1: Stettler, NCRR K23 RR16073-01; 07/01 - 06/06):

The research component of the program proposes a three-year prospective cohort study to investigate the components of energy balance in children with Down syndrome (DS), in order to identify the causes of their increased risk for obesity. As the life expectancy of people with DS has increased, chronic diseases and the psychosocial burden associated with obesity have a significant impact on their quality of life. The primary hypothesis is that the resting energy expenditure (REE) of children with DS, measured by indirect calorimetry, is lower than the REE of healthy control subjects sharing the same family background, their siblings. The association between REE and the accretion of fat mass over a three-year follow-up period, as well as the impact of activity will also be investigated. REE, growth, and body composition will be measured by state of the art technologies available at the GCRC Nutrition Assessment Core Laboratory, and physical activity will be derived from measurement of total energy expenditure measured by doubly labeled water.

Project 7: Lifestyle activity for weight loss (P1: Wadden, ROl DK56114-03, 8/99 - 07/04):

The goal of the proposed research is to improve the maintenance of weight loss by increasing physical activity in individuals who participate in a comprehensive behavioral weight loss program. A total of 216 obese adults (108 males, 108 females) will be randomly assigned to one of three conditions: 1) structured on-site exercise; 2) structured at-home exercise; or 3) lifestyle activity. Subjects will be treated for 40 weeks and then followed through week 104. We predict that, at week 104, subjects in the lifestyle condition will maintain their end-of-treatment weight losses significantly better than those in the two other conditions and will have significantly greater improvements in health and psychosocial status. This will result from their maintaining significantly higher levels of physical activity during the follow-up period.

Project 8: Study of health outcomes of weight loss (P1: Wadden, U01 DK57135-03, 09/99 - 08/06): Look AHEAD is a multicenter, randomized clinical trial to study two primary research questions: 1) Do interventions designed to produce sustained weight loss in obese individuals with type 2 diabetes mellitus improve health? 2) How do the benefits and risk of interventions designed to produce weight loss compare with the benefits and risk related to treatment of obesity-related comorbid conditions in the absence of weight-loss interventions? The trial is anticipated to enroll 6000 obese patients with type 2 diabetes for a period of 4 to 7 years. The trial compares community care with intensive lifestyle interventions designed to produce sustained long-term weight loss (with or without weight-loss medications, as will be determined by the study group). A number of outcomes will be studied, including progression of atherosclerosis as assessed by carotid ultrasound, glycemic control, cardiovascular and cerebrovascular event rates, cardiovascular and all-cause mortality, and cardiovascular risk factors. Additional outcomes may be studied including health-related quality of life measures; changes in body fat and body fat distribution; diabetes-specific microvascular and macrovascular outcomes; musculoskeletal outcomes, such as bone density; changes in use of medications; and fitness measures.

Project 9: A church-based intervention to increase physical activity (P1: Whitt, KOl HL70449-0, 05/02 - 04/07):

Physical activity has been shown to decrease the risk of diseases that affect a large proportion of the African American community, such as coronary heart disease, hypertension, diabetes, and obesity. In spite of the fact that increased physical activity has been shown to decrease the risk of.these diseases, relatively few physical activity interventions have involved African Americans. Several church-based lifestyle interventions have been successful at improving health-related risk factors among African Americans, including smoking cessation, weight reduction, and cholesterol and high blood pressure education programs; however, no published studies have been identified that specifically target physical activity as the primary outcome of interest. The specific aims of the proposed research project will be to: 1) develop a physical activity program that can be incorporated into on-going church-related activities; 2) assess the feasibility of implementation of this program in a church setting; 3) assess program acceptance by participants; and 4) assess program effects on physical activity (primary outcome), blood pressure, body mass index, waist circumference, weight loss and/or weight gain prevention, stress, and diet.

Project 10: Building better bones in children (P1: Zemel; ROl HD37748-01, 06/99-05/04):

Increased calcium intake has proven effective in increasing bone mineral density in children, but the effect disappears when calcium supplements are discontinued. This study will develop and implement a Behavioral Modification - Nutrition Education (BM-NE) intervention program aimed at increasing dietary calcium. Male and female subject (n = 154), ages 7 to 10 years (Tanner stage I or II), will be randomly assigned to participate in an intensive BM-NE intervention group to increase calcium intake to 1500 mg/d or a group that will receive usual care (UC) as counseling on bone health. The BM-NE program will consist of five separate group sessions for parents and children over a 5 to 6 week period, and will use individualized plans to increase calcium intake. Participants will be recruited into two groups: a group of healthy children (i.e., no known chronic disease or previous oral steroid exposure) with no know risk factors, and a group of healthy children with potential risk factors for low bone density (previous fracture from usual childhood activities, daily refusal or lactose intolerance, and family history of osteoporosis). These two groups will be equally represented in their assigmnent to BM-NE and US groups. This latter strategy will be used to determine whether the presence of risk factors influences participant compliance with the programs. We hypothesize that (a) at the end of 36 months the BM-NE group will have increased dietary calcium of at least 300 mg/d in the no-risk BM-NE group compared with those receiving UC, (b) baseline calcium intake and presence of risk factors will be associated with changes in calcium intake over the course of the study, and (c) after controlling for important covariates, such as increases in body size and sexual and skeletal maturation, changes in BMD will be associated with calcium intake and physical activity.

Studies currently recruiting

coming soon

(c) 2003 center for clinical epidemiology and biostatistics · export-study@cceb.med.upenn.edu