Research and Evaluation

The Physical Activity and Obesity Epidemiology Laboratory was established at Pennington Biomedical Research Center in August 2007. We have several completed and on-going collaborations on epidemiological and clinical investigations. The summaries below describe some of our recent research activities.

 

Pennington Center Longitudinal Study (PCLS) 

 

The PCLS draws its data from screening and study-specific information contained in the central PBRC clinic database and the bio-repository. These data have been collected over the last twenty years during the clinical research studies conducted at PBRC. The existing PCLS cross-sectional dataset represents an extract of the central clinic database that has undergone further data management to identify unique individuals and establish a baseline that maximizes the currently available data. The PCLS represents an effort to utilize the data collected on research volunteers to develop a cohort that can be used for cross-sectional analyses and can be followed prospectively for the development of a variety of health-related outcomes.

 

Selected Publications

 

Sung Y.J., L. Pérusse, M.A. Sarzynski, M. Fornage, S. Sidney, B. Sternfeld, T. Rice, G. Terry, D.R. Jacobs, P.T. Katzmarzyk, J Curran, J.J. Carr, J. Blangero, S. Ghosh, J.P. Despres, T. Rankinen, D.C. Rao and C. Bouchard. Genome-wide association studies suggest sex-specific loci associated with abdominal and visceral fat. International Journal of Obesity and Related Metabolic Disorders 2016; Advance Online Publication October 20, 2015.

 

Camhi S.M. and P.T. Katzmarzyk. Differences in body composition between metabolically healthy obese and metabolically abnormal obese adults. International Journal of Obesity and Related Metabolic Disorders 2014;38:1142-1145.

 

Katzmarzyk P.T., G. Hu, W.T. Cefalu, E. Mire and C. Bouchard. The importance of waist circumference and body mass index for mortality risk in diabetic adults. Diabetes Care 2013:36:3128-3130.

 

Katzmarzyk P.T., F.L. Greenway, S.B. Heymsfield and C. Bouchard. Clinical utility and reproducibility of visceral adipose tissue measurements derived from dual-energy X-ray absorptiometry in white and African American adults. Obesity 2013:21:2221-2224.

 

Katzmarzyk P.T., E. Mire, G.A. Bray, F.L. Greenway, S.B. Heymsfield and C. Bouchard. Anthropometric markers of obesity and all-cause mortality in white and African American adults: The Pennington Center Longitudinal Study. Obesity 2013;21:1070-1075.

 

Katzmarzyk P.T., S.B. Heymsfield and C. Bouchard. Clinical utility of visceral adipose tissue for the identification of cardiometabolic risk in white and African American adults. American Journal of Clinical Nutrition 2013;97:480-489.

 

Staiano A.E., C. Bouchard and P.T. Katzmarzyk. BMI-specific waist circumference thresholds to discriminate elevated cardiometabolic risk in white and African American adults. Obesity Facts 2013;6:317-324.

 

Katzmarzyk P.T., E. Mire and C. Bouchard. Abdominal obesity and mortality: The Pennington Center Longitudinal Study. Nutrition and Diabetes 2012;2:e42.

 

Camhi S.M. and P.T. Katzmarzyk. Total and femoral neck bone mineral density in a sample of men and women. Applied Physiology, Nutrition and Metabolism 2012; 37:947-954.

 

Barreira T.V., D.M. Harrington, A.E. Staiano, S.B. Heymsfield, S.R. Smith and P.T. Katzmarzyk. Anthropometric correlates of total body fat, abdominal adiposity and cardiovascular disease risk factors in a biracial sample of men and women. Mayo Clinic Proceedings 2012;87:452-460.

 

Katzmarzyk P.T., T.V. Barreira, D.M. Harrington, A.E. Staiano, S.B. Heymsfield and J.M. Gimble. Relationship between abdominal fat and bone mineral density in white and African American adults. Bone 2012; 50:576-579.

 

Barreira T.V., D.M. Harrington, A.E. Staiano, S.B. Heymsfield and P.T. Katzmarzyk. Body adiposity index, body mass index and body fat in white and black adults. Journal of the American Medical Association (JAMA) 2011;306:828-830.

 

Newton Jr., R.L., C. Bouchard, G.A. Bray, F.L. Greenway, W.D. Johnson, E. Ravussin, D.H. Ryan and P.T. Katzmarzyk. Abdominal adiposity depots are correlates of adverse cardiometabolic risk factors in Caucasian and African American adults. Nutrition and Diabetes Nutrition and Diabetes 2011; 1: e2; doi:10.1038/nutd.2010.2.


Hu G., C. Bouchard, G.A. Bray, F.L. Greenway, W.D. Johnson, R.L. Newton, E. Ravussin, D.H. Ryan and P.T. Katzmarzyk. Trunk versus extremity adiposity and cardiometabolic risk factors in white and African American adults. Diabetes Care 2011;34:1415-1418.


Katzmarzyk P.T., G.A. Bray, F.L. Greenway, W.D. Johnson, R.L. Newton, Jr., E. Ravussin, D.H. Ryan, and C. Bouchard. Ethnic-specific body mass index and waist circumference thresholds. Obesity 2011;19:1272-1278.


Broyles S.T., C. Bouchard, G.A. Bray, F.L. Greenway, W.D. Johnson, R.L. Newton, Jr., E. Ravussin, D.H. Ryan, S.R. Smith and P.T. Katzmarzyk. Consistency of fat to fat-free mass relationship across race and sex groups. British Journal of Nutrition 2011;105:1272-1276.


Camhi S.M., G.A. Bray, C. Bouchard, F.L. Greenway, W.D. Johnson, R.L. Newton, Jr., E. Ravussin, D.H. Ryan, S.R. Smith and P.T. Katzmarzyk. The relationship of waist circumference and BMI to visceral, subcutaneous, and total body fat: Sex and race differences. Obesity 2011;19:402-408.


Sullivan R., W.D. Johnson and P.T. Katzmarzyk. Waist circumference is an independent correlate of errors in self-reported body mass index. Obesity 2010;11:2237-2239.


Katzmarzyk P.T., G.A. Bray, F.L. Greenway, W.D. Johnson, R.L. Newton, Jr., E. Ravussin, D.H. Ryan, S.R. Smith and C. Bouchard. Racial differences in abdominal depot-specific adiposity in white and African American adults. American Journal of Clinical Nutrition 2010;91:7-15.


Johnson W.D., C. Bouchard, R. Newton, Jr., D. Ryan and Katzmarzyk P.T. Ethnic differences in self-reported and measured obesity. Obesity 2009;17:571-577.

  

Promoting Successful Weight Loss in Primary Care in Louisiana (PROPEL)

 

Obesity is a very common and serious medical and social condition, with Louisiana currently ranked among the states with the highest levels of obesity. Obesity is a condition that increases the risk of type 2 diabetes, heart disease, stroke, gallbladder disease, respiratory problems, quality of life, and several cancers. Obesity and its health problems greatly affect underserved populations, and Louisiana is characterized by high levels of poverty, low health literacy, and food insecurity, all of which may contribute to the high obesity levels in the State. PROPEL is a cluster-randomized, two-arm controlled trial in primary care settings. A total of 18 primary care clinics inclusive of low income populations with a high percentage of African Americans from urban and rural areas across Louisiana will be randomized to either: 1) intervention or 2) usual care. The sample will include 1,080 obese (BMI 30-45 kg/m2) patients (18 clinics, 60 patients / clinic). The primary aim of this trial is to develop and test the effectiveness of a 24 month, patient-centered, pragmatic and scalable obesity treatment program delivered within primary care in an underserved population. Trained health coaches embedded in the primary care clinic will deliver the active intervention - a comprehensive, “high-intensity" program, as recommended first-line therapy by the 2013 AHA/ACC/TOS Obesity Guidelines, and based on the Look AHEAD intensive lifestyle intervention which was an adaptation of the Diabetes Prevention Program (DPP). Patients in the intervention arm will attend weekly (15 in-person) sessions in the first six months, followed by monthly sessions for the remaining 18 months. Patients assigned to the usual care arm will continue to interact with their primary care practitioner (PCP) according to their usual schedule, and will be invited to attend a series of social meetings on topics of interest, including importance of sleep for health, household money management, family coping skills, smoking cessation, etc. PCPs in the usual care arm will receive a webinar describing the current CMS approach to reimbursing for obesity treatment, and a reminder informational brochure will be sent to the PCPs each year. Patients in both arms will be assessed on primary and secondary outcome measures at baseline, and at 6, 12, 18 and 24 months of intervention. PROPEL is funded by the Patient-Centered Outcomes Research Institute (PCORI).

 

Selected Publications

Kennedy B.M., K.B. Kennedy, D.F. Sarpong and P.T. Katzmarzyk. Perceptions of obesity treatment options among healthcare providers and low-income primary care patients. The Ochsner Journal 2016: In Press: Accepted for Publication on January 8, 2016.

 

Anthropometric Assessment of Abdominal Obesity and Health Risk in Children and Adolescents

 

Abdominal fat, in particular intra-abdominal visceral adipose tissue, is considered to be the most dyslipidemic and atherogenic fat depot in the human body. Intra-abdominal visceral adipose tissue and total body fat can be measured precisely and reliably in a laboratory setting using advanced imaging techniques; however, reliable clinical measurements of pediatric intra-abdominal visceral adipose tissue and total body fat are yet to be developed. Thus, the specific aims of this study are to 1) identify reliable landmarks and methodology for the measurement of pediatric waist circumference that are associated with intra-abdominal visceral adipose tissue and total body fat across the pediatric age, total body adiposity, and maturity range among African American and Caucasian children and adolescents, 2) determine if waist circumference in combination with other anthropometric indices is a better predictor of intra-abdominal visceral adipose tissue and total body fat than waist circumference alone across the pediatric age, total body adiposity, and maturation range, and 3) develop and determine the clinical utility of pediatric race-sex-specific waist circumference thresholds for the identification of elevated chronic disease risk factors across the pediatric age, total body adiposity, and maturation range. We will accomplish these aims by conducting a cross-sectional study of 100 African American boys, 100 Caucasian boys, 100 African American girls, and 100 Caucasian girls 5 to 18 years of age. Waist circumference will be measured at the four common anatomic sites used in pediatric research: 1) superior border of the iliac crest, 2) midpoint between the iliac crest and the lowest rib, 3) umbilicus, and 4) minimal waist. Additional body dimensions will be obtained in order to determine the clinical utility of combining waist circumference with other measurements in predicting intra-abdominal visceral adipose tissue and total body fat, which will be assessed using advanced imaging techniques. The identification of the most appropriate waist circumference landmarks and measurement techniques is important for the clinical identification of children at elevated obesity-related health risk and for the standardization of obesity surveillance strategies within and between countries. This study was funded by the U.S. National Institutes of Health.

 

Selected Publications

 

Staiano A.E., S.T. Broyles and P.T. Katzmarzyk. School term versus school holiday: Associations with children’s physical activity, screen time, diet and sleep. International Journal of Environmental Research and Public Health 2015;12:8861-8870.

 

Barreira T.V., S.T. Broyles, A.K. Gupta and P.T. Katzmarzyk. Relationship of anthropometric indices to abdominal and total body fat in youth: sex and race differences. Obesity 2014;22:1345-50.

 

Staiano A.E., A.K. Gupta and P.T. Katzmarzyk. Cardiometabolic risk factors and fat distribution in children and adolescents. Journal of Pediatrics 2014;164:560-565.

 

Katzmarzyk P.T. and C. Bouchard. Where is the beef? Waist circumference is more highly correlated with BMI and total body fat than with abdominal visceral fat in children. International Journal of Obesity and Related Metabolic Disorders 2014:38:753-754.

 

Staiano A.E., S.T. Broyles, A.K. Gupta, R.M. Malina and P.T. Katzmarzyk. Maturity-associated variation in total and depot-specific body fat in children and adolescents. American Journal of Human Biology 2013:25:473-479.

 

Harrington D.M., A.E. Staiano, S.T. Broyles, A. Gupta and P.T. Katzmarzyk. Sex- and ethnic-specific BMI percentiles for the identification of abdominal obesity and metabolic risk in children and adolescents: Evidence in support of the CDC 95th percentile. European Journal of Clinical Nutrition 2013;67:218-222.

 

Staiano A.E., S.T. Broyles, A.K. Gupta and P.T. Katzmarzyk. Ethnic and sex differences in visceral, subcutaneous, and total body fat in children and adolescents. Obesity 2013;21:1251-1255.

 

Barreira T.V., A.E. Staiano and P.T. Katzmarzyk. Validity assessment of a portable bioimpedance scale to estimate body fat percentage in white and African American children and adolescents. Pediatric Obesity 2013;8:e29-e32.

 

Harrington D.M., A.E. Staiano, S.T. Broyles, A.K. Gupta and P.T. Katzmarzyk.  Waist circumference measurement site does not affect relationships with visceral adiposity and cardiometabolic risk factors in children. Pediatric Obesity 2013;8:199-206.

 

Staiano A.E., D.M. Harrington, S.T. Broyles, A.K. Gupta and P.T. Katzmarzyk. Television, adiposity, and cardiometabolic risk in children and adolescents. American Journal of Preventive Medicine 2013;44:40-47.

 

Broyles S.T., A.E. Staiano, K.T. Drazba, A. Gupta, M. Sothern and P.T. Katzmarzyk. Elevated C-reactive protein in children from risky neighborhoods: Evidence for a stress pathway linking neighborhoods and inflammation in children. PloS ONE 2012; 7(9):e45419.

 

InSight

 

Dietary intervention and other strategies to prevent unhealthy weight gain and the development of obesity should be based on knowledge of dietary, physiological, genetic, and behavioral determinants and their contributing interactions.  Identifying these determinants is difficult because physiological susceptibility to specific dietary and behavioral factors implicated in unhealthy weight gain differs between populations and among individuals within populations.  The research challenge is identifying specific determinants in a free-living, U.S. adult population. InSight is a prospective longitudinal study of free-living normal weight adults aged 20-35 at baseline. The primary aim of InSight is to identify the most important determinants of weight gain and the development of overweight and obesity.  As a secondary aim, we will identify a single parsimonious collection of factors and develop strategies to mitigate the risks of developing obesity. The sample is equally divided by sex and race (white and African American). The participants are undergoing a series of assessments in the domains of diet, physiology, genetics, and behavior at baseline and will return every 12 months for 10 years. Advanced longitudinal and multivariate statistical and epidemiologic techniques will be used to identify and model underlying correlation structures among the measurements collected by the research team pertaining to diet (dietary intake of fat, sugar-sweetened beverages, calcium, and fiber, and portion size) physiological factors (energy expenditure, insulin sensitivity and secretion, detailed body composition, skeletal muscle metabolism, adipocyte factors), genetic factors (sensory perception and candidate genes), behavioral factors (dietary restraint, disinhibition, food neophobia, sedentary behavior, and physical activity), demographics, and other possible contributing factors to unhealthy weight gain over time. 

 

Selected Publications

 

Raja G.K., M.A. Sarzynski, P.T. Katzmarzyk, W.D. Johnson, Y. Tchoukalova, S.R. Smith and C. Bouchard. Commonality versus specificity among adiposity traits in normal-weight and moderately overweight adults. International Journal of Obesity and Related Metabolic Disorders 2014;38:719-723.

 

Harrington D.M., C.K. Martin, E. Ravussin and P.T. Katzmarzyk. The relationship between objectively measured physical activity and subjective measures of hunger and satiety. Appetite 2013;67:1-7.

 

Tudor-Locke C., C.K. Martin, M.M. Brashear, J.C. Rood, P.T. Katzmarzyk and W.D. Johnson. Predicting doubly labeled water energy expenditure from ambulatory activity. Applied Physiology, Nutrition and Metabolism 2012;37:1091-1100.

 

International Study of Childhood Obesity, Lifestyle and the Environment (ISCOLE)

 

Childhood obesity remains a major public health concern, and key questions about lifestyle and childhood obesity remain to be answered. Large multi-country studies of childhood obesity have not been truly global and are rare outside of Europe. Given that each country has limited variability in obesity and potentially modifying factors, an international study is able to maximize variability in these factors. The primary aim of ISCOLE is to determine the relationships between lifestyle behaviours and obesity in a multi-national study of children, and to investigate the influence of higher-order characteristics such as behavioural settings, and the physical, social and policy environments, on the observed relationships within and between countries. The study involved the collection of dietary, physical activity, and obesity data using a rigorous, standardized protocol across all countries. The final sample includes more than 7000 children from 12 countries on every inhabited continent. ISCOLE represents a multi-national collaboration among all world regions, and represents a global effort to increase research understanding, capacity and infrastructure in childhood physical activity and obesity. More than 240 people have worked on ISCOLE to date, including junior and senior scientists, post-doctoral fellows, students and staff. ISCOLE was funded by The Coca-Cola Company.

 

Selected Publications

Katzmarzyk P.T., D.G. Lambert and T.S. Church. Introduction to the International Study of Childhood Obesity, Lifestyle and the Environment (ISCOLE). International Journal of Obesity Supplements 2015(2):S1-S2.

 

Broyles S.T., K.D. Denstel, T.S. Church, J.-P. Chaput, M. Fogelholm, G. Hu, R. Kuriyan, A. Kurpad, E.V. Lambert, C. Maher, J. Maia, V. Matsudo, T. Olds, V. Onywera, O.L. Sarmiento, M. Standage, M.S. Tremblay, C. Tudor-Locke, P. Zhao and P.T. Katzmarzyk for the ISCOLE Research Group. The epidemiological transition and the global childhood obesity epidemic. International Journal of Obesity Supplements 2015;5(2):S3-S8.

 

Mikkilä V., H. Vepsäläinen, T. Saloheimo, S.A. Gonzalez, J.D. Meisel, G. Hu, C.M. Champagne, T.S. Church, P.T. Katzmarzyk, R. Kuriyan, A. Kurpad, E.V. Lambert, C. Maher, J. Maia, V. Matsudo, T.S. Olds, V. Onywera, O.L. Sarmiento, M. Standage, M.S. Tremblay, C. Tudor-Locke, P. Zhao and M. Fogelholm for the ISCOLE Research Group. An international comparison of dietary patterns in 9-11 year old children. International Journal of Obesity Supplements 2015;5(2):S17-S21.

 

Saloheimo T., S.A. González, M. Erkkola, D.M. Milauskas, J.D. Meisel, C.M. Champagne, C. Tudor-Locke, O.L. Sarmiento, P.T. Katzmarzyk and M. Fogelholm for the ISCOLE Research Group. The reliability and validity of a short food frequency questionnaire among 9-11 year olds: A multinational study on 3 middle income and high income countries. International Journal of Obesity Supplements 2015;5(2):S22-S28.

 

Barreira T.V., J.M. Schuna, C. Tudor-Locke, J.-P. Chaput, T.S. Church, M. Fogelholm, G. Hu, R. Kuriyan, A. Kurpad, E.V. Lambert, C. Maher, J. Maia, V. Matsudo, T. Olds, V. Onywera, O.L. Sarmiento, M. Standage, M.S. Tremblay, P. Zhao and P.T. Katzmarzyk for the ISCOLE Research Group. Reliability of accelerometer-determined physical activity and sedentary behavior in school-aged children: A 12 country study. International Journal of Obesity Supplements 2015;5(2):S29-S35.

 

Broyles S.T., K.T. Drazba, T.S. Church, J.-P. Chaput, M. Fogelholm, G. Hu, R. Kuriyan, A. Kurpad, E.V. Lambert, C. Maher, J. Maia, V. Matsudo, T. Olds, V. Onywera, O.L. Sarmiento, M. Standage, M.S. Tremblay, C. Tudor-Locke, P. Zhao and P.T. Katzmarzyk for the ISCOLE Research Group. Development and reliability of an audit tool to assess the school physical activity environment across 12 countries. International Journal of Obesity Supplements 2015;5(2):S36-S42.

 

Katzmarzyk P.T., T.V. Barreira, S.T. Broyles, J.-P. Chaput, M. Fogelholm, G. Hu, R. Kuriyan, A. Kurpad, E.V. Lambert, C. Maher, J. Maia, V. Matsudo, T. Olds, V. Onywera, O.L. Sarmiento, M. Standage, M.S. Tremblay, C. Tudor-Locke, P. Zhao and T.S. Church for the ISCOLE Research Group. Association between body mass index and body fat in 9-11 year old children from countries spanning a range of human development. International Journal of Obesity Supplements 2015;5(2):S43-S46.

 

Chaput J.-P., P.T. Katzmarzyk, A.G. LeBlanc, M.S. Tremblay, T.V. Barreira, S.T. Broyles, M. Fogelholm, G. Hu, R. Kuriyan, A. Kurpad, E.V. Lambert, D.E. Rae, C. Maher, J. Maia, V. Matsudo, V. Onywera, O.L. Sarmiento, M. Standage, C. Tudor-Locke, P. Zhao and T. Olds for the ISCOLE Research Group. Associations between sleep patterns and lifestyle behaviors in children: An international comparison. International Journal of Obesity Supplements 2015;5(2):S59-S65.

 

Katzmarzyk P.T., T.V. Barreira, S.T. Broyles, C.M. Champagne, J.-P. Chaput, M. Fogelholm, G. Hu, W.D. Johnson, R. Kuriyan, A. Kurpad, E.V. Lambert, C. Maher, J. Maia, V. Matsudo, T. Olds, V. Onywera, O.L. Sarmiento, M. Standage, M.S. Tremblay, C. Tudor-Locke, P. Zhao and T.S. Church for the ISCOLE Research Group. Relationship between lifestyle behaviors and obesity in 9-11 year old children: Results from a 12-country study. Obesity 2015;23:1696-1702.

 

Katzmarzyk P.T., T.V. Barreira, S.T. Broyles, C.M. Champagne, J.-P. Chaput, M. Fogelholm, G. Hu, W.D. Johnson, R. Kuriyan, A. Kurpad, E.V. Lambert, C. Maher, J. Maia, V. Matsudo, T.S. Olds, V. Onywera, O.L. Sarmiento, M. Standage, M.S. Tremblay, C. Tudor-Locke, P. Zhao and T.S. Church for the ISCOLE Research Group. Physical activity, sedentary time and obesity in an international sample of children. Medicine and Science in Sports and Exercise 2015;47:2062-2069.

 

Tudor-Locke C., T.V. Barreira, J.M. Schuna Jr., E.F. Mire, J.-P. Chaput, M. Fogelholm, G. Hu, R. Kuriyan, A. Kurpad, E.V. Lambert, C. Maher, J. Maia, V. Matsudo, T. Olds, V. Onywera, O.L. Sarmiento, M. Standage, M.S. Tremblay, P. Zhao, T.S. Church and P.T. Katzmarzyk. Improving wear time compliance with a 24-hour waist-worn accelerometry protocol in the International Study of Childhood Obesity, Lifestyle and the Environment (ISCOLE). International Journal of Behavioural Nutrition and Physical Activity 2015;12:11.

 

Barreira T.V., J.M. Schuna, Jr., E.F. Mire, P.T. Katzmarzyk, J.-P. Chaput, G. Leduc and C. Tudor-Locke. Identifying children’s nocturnal sleep using 24-hour waist accelerometry. Medicine and Science in Sports and Exercise 2015;47:937-943.

 

Katzmarzyk P.T., T.V. Barreira, S.T. Broyles, C.M. Champagne, J.-P. Chaput, M. Fogelholm, G. Hu, W.D. Johnson, R. Kuriyan, A. Kurpad, E.V. Lambert, J. Maia, V. Matsudo, C. Maher, T. Olds, V. Onywera, O.L. Sarmiento, M. Standage, M.S. Tremblay, C. Tudor-Locke, P. Zhao and T.S. Church. The International Study of Childhood Obesity, Lifestyle and the Environment (ISCOLE): Design and Methods. BMC Public Health 2013;13:900.

 

Delta Obesity Prevention Research Unit

 

Reducing the high and increasing prevalence of obesity is a federal priority. The current high levels of obesity are taking a staggering toll on public and personal health in the USA. The Pennington Biomedical Research Center is part of a research consortium that includes multiple universities in Louisiana, Mississippi, and Arkansas. The mission of this consortium is to conduct nutrition research to prevent obesity in at-risk, rural populations in the Lower Mississippi Delta of Arkansas, Louisiana, and Mississippi. The Agricultural Research Service (ARS) is coordinating this major research endeavor that brings together the talents of ARS and other research cooperators in the tri-state region with the ultimate goal of promoting optimal health and reducing the burden of obesity in this population. USDA funding for this research initiative at PBRC has been continuous since 1998. The partner institutions include the Pennington Biomedical Research Center, Southern University and A&M College, Baton Rouge, LA; University of Southern Mississippi, Alcorn State University, MS; University of Arkansas Pine Bluff, Arkansas Children’s Hospital Research Institute, AR; Delta NIRI Executive Office, AR. The current USDA funded project at PBRC is aimed at increasing physical activity among residents of the Lower Mississippi Delta. This project is being conducted in two phases. During Phase I we will determine the feasibility of adapting physical activity recommendations by incorporating pedometers (step-counters) as self-monitoring tools within the context of an education program. Specifically, participants will be instructed to achieve DG physical activity recommendations and monitor the number of steps they take congruent with this success. Lessons learned from the feasibility study will be incorporated into the design of Phase II, in which we will conduct a properly powered, randomized controlled effectiveness trial of physical activity and adapted DG eating patterns to reduce unhealthy weight gain. An expectation from the short-term nature of the feasibility study is an immediate increase in physical activity (both number of steps and time in moderate to vigorous activity as assessed by accelerometer) based on the adopted use of a pedometer. The Phase II study will determine if the implementation of these newly identified step-based physical activity recommendations can be used directly to achieve and sustain recommended levels of physical activity in the Lower Mississippi Delta population. 

 

Selected Publications

 

Barreira T.V., D.M. Harrington, J.M. Schuna, C. Tudor-Locke and P.T. Katzmarzyk. Pattern changes in step count accumulation and peak cadence due to a physical activity intervention. Journal of Science and Medicine in Sports 2016:19:227-231.

 

Harrington D.M., C.M. Champagne, S.T. Broyles, W.D. Johnson, C. Tudor-Locke and P.T. Katzmarzyk. Cardiometabolic risk factor response to a lifestyle intervention: A randomized trial. Metabolic Syndrome and Related Disorders 2015;13:125-131.

 

Harrington D.M., C.M. Champagne, S.T. Broyles, W.D. Johnson, C. Tudor-Locke and P.T. Katzmarzyk. Steps Ahead: A randomized trial to reduce unhealthy weight gain in the Lower Mississippi Delta. Obesity 2014;22:E21-28.

 

Barreira T.V., C. Tudor-Locke, C.M. Champagne, S.T. Broyles, W.D. Johnson and P.T. Katzmarzyk. Comparison of GT3X accelerometer and YAMAX pedometer steps/day in a free-living sample of overweight and obese adults. Journal of Physical Activity and Health 2013;10:263-270.


Katzmarzyk P.T., C.M. Champagne, C. Tudor-Locke, S.T. Broyles, D. Harsha, B.M. Kennedy and W.D. Johnson. A short-term physical activity randomized trial in the Lower Mississippi Delta. PloS ONE 2011;6(10):e26667. doi:10.1371/journal.pone.0026667.


Harrington D.M., C. Tudor-Locke, C.M. Champagne, S.T. Broyles, D. Harsha, B.M. Kennedy, W.D. Johnson, R. Allen and P.T. Katzmarzyk. Step-based translation of physical activity guidelines in the Lower Mississippi Delta. Applied Physiology, Nutrition and Metabolism 2011;36:583-585.

  

Bogalusa Heart Study

 

The Bogalusa Heart Study is a community-based investigation of the natural history of cardiovascular disease from childhood into adulthood. Eligible participants were drawn from children and adolescents living in Ward 4 of Washington Parish in South East Louisiana, a bi-racial community (65% white, 35% black) of approximately 20,000 people.  Several cross-sectional surveys have been conducted between 1973 and 2002, and many individuals have participated in multiple surveys. A longitudinal cohort of participants in embedded into the cross-sectional surveys, allowing for the study of childhood risk factors and adult health outcomes. The Bogalusa Heart Study is administered by Dr. Gerald Berenson at the Tulane University Center for Cardiovascular Health. We collaborated for several years with Dr. Berenson and the Bogalusa Heart Study investigators mainly in the area of pediatric obesity.

    

Selected Publications

 

Camhi S.M., P.T. Katzmarzyk, S.T. Broyles, S.R. Srinivasan, W. Chen, C. Bouchard and G.S. Berenson. Subclinical atherosclerosis and metabolic risk: Role of BMI and waist circumference. Metabolic Syndrome and Related Disorders 2011;9:119-125.


Freedman D.S., P.T Katzmarzyk, W.H. Dietz, S.R. Srinivasan and G.S. Berenson. The relation of BMI and skinfold thicknesses to risk factors among young and middle-aged adults: The Bogalusa Heart Study. Annals of Human Biology 2010;37:726-737.


Broyles S.T., P.T. Katzmarzyk, S.R. Srinivasan, W. Chen, C. Bouchard, D.S. Freedman and
G.S. Berenson. The pediatric obesity epidemic continues unabated in Bogalusa, Louisiana.
Pediatrics 2010;125:900-905.


Camhi S.M., P.T. Katzmarzyk, S. Broyles, S.R. Srinivasan, W. Chen, C. Bouchard and G.S.
Berenson. Predicting adult BMI-specific cardiometabolic risk from childhood. Metabolic
Syndrome and Related Disorders
2010;8:165-172.


Freedman D.S., P.T. Katzmarzyk, W.H. Dietz, S.R Srinivasan, and G.S. Berenson. The
relation of BMI and skinfold thicknesses to cardiovascular disease risk factors among
children: The Bogalusa Heart Study. American Journal of Clinical Nutrition 2009;90:210-216.


Sisson S.B., P.T. Katzmarzyk, S.R. Srinivasan, W. Chen, D. Freedman, C. Bouchard and G.S. Berenson. Ethnic differences in BMI, subcutaneous fat and waist girth in children and youth. Obesity 2009;17:2075-2081.


Janssen I., P.T. Katzmarzyk, S. R. Srinivasan, W. Chen, R.M. Malina, C. Bouchard and G.S. Berenson. The clinical utility of childhood body mass index in the prediction of adult disease: Comparison of national reference and international guidelines. Obesity Research 2005;13:1106-1115.


Janssen I., P.T. Katzmarzyk, S. R. Srinivasan, W. Chen, R.M. Malina, C. Bouchard and G.S. Berenson. Combined influence of the body mass index and waist circumference on coronary heart disease risk factors in children and adolescents. Pediatrics 2005;155:1623-1630.


Katzmarzyk P.T., S. R. Srinivasan, W. Chen, R.M. Malina, C. Bouchard and G.S. Berenson. Body mass index, waist circumference, and clustering of cardiovascular disease risk factors in a biracial sample of children and adolescents. Pediatrics 2004;114:e198-e205.

 

Canadian Physical Activity Longitudinal Study (PALS)

 

PALS is a cohort study of individuals aged 15 years and older who originally participated in the nationally representative 1981 Canada Fitness Survey and/or the 1988 Campbell’s Survey of Well-Being in Canada. Participant information was used to match to the Canadian Mortality Database in 1994, and participants were traced and sent a follow-up self-administered questionnaire pertaining to a variety of health-related topics between 2002 and 2004. We are currently investigating the role of physical activity and obesity in the prevention of chronic disease and premature mortality in this cohort, which has now been followed for 20 years.

Selected Publications

 

Katzmarzyk P.T. Standing and mortality in a prospective cohort of Canadian adults. Medicine and Science in Sports and Exercise 2014;46:940-946.

 

Mason C., C.L. Craig, L. Gauvin and P.T. Katzmarzyk. Opposing effects of waist and extremity circumferences on the risk of incident diabetes. Canadian Journal of Diabetes 2009;33:85-91

 

Katzmarzyk P.T., T.S. Church, C.L. Craig and C. Bouchard. Sitting time and mortality from all causes, cardiovascular disease, and cancer. Medicine and Science in Sports and Exercise 2009;41:998-1005.

 

Herman K.M., C.L. Craig, L. Gauvin and P.T. Katzmarzyk. Tracking of obesity and physical activity from childhood to adulthood: The Physical Activity Longitudinal Study. International Journal of Pediatric Obesity 2009; 4:281-288. .

 

Barnett T.A., L. Gauvin, C.L. Craig, and P.T. Katzmarzyk. Distinct trajectories of leisure time physical activity in adults and predictors of trajectory class membership: a 22 year cohort study. International Journal of Behavioural Nutrition and Physical Activity 2008; 5:57 (E-Pub).

 

Mason C., C.L. Craig and P.T. Katzmarzyk. Influence of central and extremity circumferences on all-cause mortality in men and women. Obesity 2008;16:2690-2695.

 

Mason C., P.T. Katzmarzyk, C.L. Craig and L. Gauvin. Mortality and self-rated health in Canada. Journal of Physical Activity and Health 2007;4:423-433.

 

Katzmarzyk P.T., C.L. Craig and L. Gauvin. Adiposity, physical fitness and incident diabetes: The Physical Activity Longitudinal Study. Diabetologia 2007;50:538.

 

Brien S., P.T. Katzmarzyk, C.L. Craig and L. Gauvin. Physical activity, cardiorespiratory fitness and body mass index as predictors of substantial weight gain and obesity: The Canadian Physical Activity Longitudinal Study. Canadian Journal of Public Health 2007;98:121-124.

 

Barnett T.A., L. Gauvin, C.L. Craig and P.T. Katzmarzyk. Modifying effects of sex, age, and education on 22-Year trajectory of leisure-time energy expenditure in a Canadian cohort. Journal of Physical Activity and Health 2007;4: 153-166.

 

Mason C., S. Brien, C.L. Craig, L. Gauvin and P.T. Katzmarzyk. Musculoskeletal fitness and weight gain in Canada. Medicine and Science in Sports and Exercise 2007;39:38-43.

 

Katzmarzyk P.T. and C.L. Craig. Independent effects of waist circumference and physical activity on risk of all-cause mortality in Canadian women. Applied Physiology, Nutrition and Metabolism 2006;31:271-276.

 

Craig C.L., L. Gauvin, S. Cragg, P.T. Katzmarzyk, T.M. Stephens, S.J. Russell, L. Potvin, M. Keast and L. Bentz. Towards a social epidemiological perspective on physical activity and health: The aims, design, and methods of the Physical Activity Longitudinal Study (PALS). Journal of Physical Activity and Health 2005;3:272-284.

 

Katzmarzyk P.T., C.L. Craig and C. Bouchard.  Adiposity, adipose tissue distribution and mortality. International Journal of Obesity and Related Metabolic Disorders 2002;26:1054-1059.

 

Katzmarzyk P.T., C.L. Craig and C. Bouchard.  Underweight, overweight and obesity: Relationships with mortality in the 13-year follow-up of the Canada Fitness Survey. Journal of Clinical Epidemiology 2001;54:916-920.

Canadian Heart Health Surveys Follow-up Study

 

The Canadian Heart Health Surveys (CHHS) is a compilation of 10 provincial, independently conducted surveys on cardiovascular risk factors, behavior and risk factor knowledge. Participants in the CHHS were selected from provincial medical insurance registries between 1986 and 1992, and a two-stage probability sampling scheme was used to ensure geographical, sex and age representativeness. Several cross-sectional studies have been published using data from the CHHS. We have recently linked the original CHHS data from five provinces to the Canadian Mortality Database (CMDB), with follow-up through December 31, 2004. This linkage was completed in 2009, and analyses of obesity, cardiovascular disease risk factor and mortality are in development. 

 

Selected Publications

 

Staiano A.E., B. Reeder, S. Elliott, M. Joffres, P. Pahwa, S. Kirkland, G. Paradis and P.T. Katzmarzyk. Physical activity, waist circumference and mortality. Applied Physiology, Nutrition and Metabolism 2012;37:1008-1013.


Staiano A.E., B. Reeder, S. Elliott, M. Joffres, P. Pahwa, S. Kirkland, G. Paradis and P.T. Katzmarzyk. Body mass index versus waist circumference as predictors of mortality in Canadian adults. International Journal of Obesity and Related Metabolic Disorders 2012;36:1450-1454.


Katzmarzyk P.T., B.A. Reeder, S. Elliott, M.R. Joffres, P. Pahwa, K.D. Raine, S.A. Kirkland and G. Paradis. Body mass index and risk of cardiovascular disease, cancer and all-cause mortality. Canadian Journal of Public Health 2012;103:147-151.


Brien S. and P.T. Katzmarzyk. Physical activity and the metabolic syndrome in Canada.
Applied Physiology, Nutrition and Metabolism 2006;31:40-47.


Mason C. and P.T. Katzmarzyk. Application of obesity treatment algorithms to Canadian
adults. European Journal of Clinical Nutrition 2005;59:797-800.


Ardern C.I., I. Janssen, R. Ross and P.T. Katzmarzyk. Development of health-related waist
circumference thresholds within BMI categories. Obesity Research 2004;12:1094-1103.

  

Evaluation Unit

 

In addition to the research activities described above, our group has also been active in the evaluation of several programs and projects, including the Louisiana Department of Health and Hospitals Chronic Disease Unit and the Blue Cross and Blue Shield of Louisiana Foundation Challenge Grant Program.  For more detailed information about our Evaluation Unit please Click Here.