Pediatric Obesity Slowly Declining Interview with:

Dr-Corinna-Koebnick Corinna Koebnick, PhD
Research scientist with Research & Evaluation
Kaiser Permanente Southern California

MedicalResearch: Please describe your study, what you were looking for, and why. 

Dr. Koebnick: This study is based on the Kaiser Permanente Southern California Children’s Health Study, which includes all children and adolescents 2–19 years of age in Southern California who are actively enrolled in a large, integrated, managed health care system. We examined the body weight from electronic health records of more than 1.3 million children and adolescents 2-19 years of age from 2008 to 2013.

The objective of this study was to investigate recent trends in pediatric obesity in Southern California between 2008 and 2013. Several recent studies have investigated national trends in childhood obesity in the United States and indicated that childhood obesity rates may have reached a plateau, but are not declining. Ours is one of the few studies that is large enough to be able to detect small changes in the prevalence of obesity in time periods of less than 10 years.

MedicalResearch: What are the findings of this study? 

Dr. Koebnick: Our study provides strong indication that the prevalence of overweight and obesity between 2008 and 2013 has not only plateaued, but also is slowly declining. While the decline in overweight and obesity was less pronounced in girls, adolescents, some minority groups and youth living in low income and low education areas, the decline was remarkably stable across all groups and significant even in minority youth and youth of lower socioeconomic status.

We found the prevalence of overweight and obesity decreased overall by 2.2 percent and 1.6 percent, respectively. This change corresponds to a relative decline of 6.1 percent in overweight youth and 8.4 percent in obese youth. Although a decline was seen across all groups, the decrease was not as strong in adolescents aged 12-19 years, in girls compared to boys, and Hispanic and black children compared to non-Hispanic whites.

MedicalResearch: Why are those findings significant? (Does it move the evidence base significantly?)

Dr. Koebnick: Several recent studies have investigated national trends in childhood obesity in the U.S. and indicated obesity rates may be plateauing, but our study is one of the few that is large enough to detect small declines in the prevalence of obesity over a relatively short time period.

Childhood obesity has reached epidemic proportions in the United States. In the last 30 years, childhood obesity has more than doubled in children and quadrupled in adolescents, with more than one third of children and adolescents found to be overweight or obese in 2012, according to the Centers for Disease Control and Prevention.

Adolescent obesity has been linked to increased mortality before 50 years of age. Obesity increases the burden of diseases such as diabetes, cardiovascular disease, kidney disease, liver disease and some cancers. Childhood overweight and obesity often continues into adulthood. Therefore reversing the trends we’ve seen in recent decades among children and adolescents is of high public interest.

Obesity is a serious issue that can continue into adulthood, which is why it is important to tackle it early on. Our study shows the prevalence of overweight and obesity is slowly declining, indicating that obesity prevention efforts may have an impact.

MedicalResearch: Why was the decrease less pronounced in certain groups (i.e., in girls compared to boys, and Hispanic and black children compared to non-Hispanic whites)? 

Dr. Koebnick: Our study cannot answer the ‘why’. It is an observational study. So, I can only speculate here. Our obesity prevention efforts are working slowly but they work better for some than for others. Now, we need to go on a search and find out what we can do better.

MedicalResearch: Why did long-term Kaiser Permanente members see a steeper decline?

Dr. Koebnick: The more pronounced decline in the prevalence of childhood overweight and obesity among long-term Kaiser Permanente members may be due to the fact that they were exposed to weight management initiatives targeting youth within the health plan. The decline may also be a result of an electronic decision support tool delivered to pediatric health care providers at point of care for overweight and obese children. Such tools can improve the performance of health care providers, the quality of care and BMI in children.

MedicalResearch: Is there a second phase to this study? Do you have plans to conduct further research into the potential factors related to this decline? 

Dr. Koebnick: We will continue our studies to hopefully answer at least part of the ‘why’. This will help us to tailor our approaches to those groups that are not declining as much.

MedicalResearch: What does this study mean for consumers, the medical profession, etc.?  What’s the take away message? 

Dr. Koebnick: Our findings show the prevalence of obese and overweight children is slowly declining, indicating that obesity prevention efforts are important and have an impact. The decline especially as it relates to childhood obesity is certainly a success, but we will have to focus on children who did not experience a decline.

Kaiser Permanente has several programs in place to address the obesity epidemic and related chronic conditions in its clinics and communities, including:

  • Industry-leading clinical prevention and treatment strategies including documenting BMI status and exercise as a vital sign, and using motivational interviewing techniques to counsel patients on healthy eating and active living.
  • Co-founding the Partnership for a Healthier America in conjunction with First Lady, Michelle Obama’s Let’s Move! Improving community health through Community Health Initiatives, a nationally recognized model for hospital and public health collaboration.
  • Supporting more than 50 health eating and active living collaboratives in California, Colorado, Georgia, the Pacific Northwest and the Mid-Atlantic region.


Secular Trends of Overweight and Obesity in Young Southern Californians 2008-2013

Corinna Koebnick, PhD, Yasmina D. Mohan, MPH, Xia Li, MSc, Deborah R. Young, PhD

The Journal of Pediatrics Available online 26 September 2015

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Corinna Koebnick, PhD (2015). Pediatric Obesity Slowly Declining om

Last Updated on October 5, 2015 by Marie Benz MD FAAD