Annals of Internal Medicine
SUMMARIES FOR PATIENTS
The Obesity Paradox in Type 2 Diabetes Mellitus The full report is titled “The Obesity Paradox in Type 2 Diabetes Mellitus: Relationship of Body Mass Index to Prognosis. A Cohort Study.” It is in the 5 May 2015 issue of Annals of Internal Medicine (volume 162, pages 610-618). The authors are P. Costanzo, J.G.F. Cleland, P. Pellicori, A.L. Clark, D. Hepburn, E.S. Kilpatrick, P. Perrone-Filardi, J. Zhang, and S.L. Atkin.
What is the problem and what is known about it so far? Obesity is a well-established risk factor for cardiovascular disease and type 2 diabetes. However, studies show that overweight patients with cardiovascular disease live longer than normal-weight patients with cardiovascular disease. This could be because sicker people lose weight. It is unclear whether patients with type 2 diabetes also live longer if they are overweight. Why did the researchers do this particular study? To compare cardiovascular disease risks and survival rates for underweight, normal-weight, overweight, and obese patients with type 2 diabetes. Who was studied? The patients had type 2 diabetes, were seen in a single diabetes center in the United Kingdom, and were part of a long-term study. They did not have cardiovascular disease at their first visit. How was the study done? Information on how long the patients had diabetes, whether they smoked cigarettes or had other chronic diseases, and physical measurements (such as weight and height) were collected at their first visit. Investigators collected information on hospitalizations for cardiovascular problems and deaths during the long-term follow-up. What did the researchers find? Patients who were overweight or obese had an increased risk for hospitalization for cardiovascular disease. Compared with normal-weight patients, underweight patients had the worst survival and overweight patients had the best survival. The survival of obese patients was not different from that of normal-weight patients. What were the limitations of the study? The investigators did not have information on causes of death, patients' fitness levels, or whether patients took medications to decrease their cholesterol levels. What are the implications of the study? Patients who have type 2 diabetes and are overweight or obese have an increased risk for cardiovascular disease. However, patients who were overweight but not obese lived longer than those who were underweight or normal weight. The explanation for these results is unknown and does not mean that patients with diabetes should try to become overweight. Patients should continue to follow a healthy lifestyle.
Summaries for Patients are a service provided by Annals to help patients better understand the complicated and often mystifying language of modern medicine. Summaries for Patients are presented for informational purposes only. These summaries are not a substitute for advice from your own medical provider. If you have questions about this material, or need medical advice about your own health or situation, please contact your physician. The summaries may be reproduced for not-for-profit educational purposes only. Any other uses must be approved by the American College of Physicians.
Ann Intern Med. 2015;162:I-26. doi:10.7326/P15-9015
I-26 © 2015 American College of Physicians
Downloaded From: http://annals.org/ by a Welch Medical Library JHU User on 06/09/2015
SUMMARIES FOR PATIENTS
The Obesity Paradox in Type 2 Diabetes Mellitus The full report is titled “The Obesity Paradox in Type 2 Diabetes Mellitus: Relationship of Body Mass Index to Prognosis. A Cohort Study.” It is in the 5 May 2015 issue of Annals of Internal Medicine (volume 162, pages 610-618). The authors are P. Costanzo, J.G.F. Cleland, P. Pellicori, A.L. Clark, D. Hepburn, E.S. Kilpatrick, P. Perrone-Filardi, J. Zhang, and S.L. Atkin.
What is the problem and what is known about it so far? Obesity is a well-established risk factor for cardiovascular disease and type 2 diabetes. However, studies show that overweight patients with cardiovascular disease live longer than normal-weight patients with cardiovascular disease. This could be because sicker people lose weight. It is unclear whether patients with type 2 diabetes also live longer if they are overweight. Why did the researchers do this particular study? To compare cardiovascular disease risks and survival rates for underweight, normal-weight, overweight, and obese patients with type 2 diabetes. Who was studied? The patients had type 2 diabetes, were seen in a single diabetes center in the United Kingdom, and were part of a long-term study. They did not have cardiovascular disease at their first visit. How was the study done? Information on how long the patients had diabetes, whether they smoked cigarettes or had other chronic diseases, and physical measurements (such as weight and height) were collected at their first visit. Investigators collected information on hospitalizations for cardiovascular problems and deaths during the long-term follow-up. What did the researchers find? Patients who were overweight or obese had an increased risk for hospitalization for cardiovascular disease. Compared with normal-weight patients, underweight patients had the worst survival and overweight patients had the best survival. The survival of obese patients was not different from that of normal-weight patients. What were the limitations of the study? The investigators did not have information on causes of death, patients' fitness levels, or whether patients took medications to decrease their cholesterol levels. What are the implications of the study? Patients who have type 2 diabetes and are overweight or obese have an increased risk for cardiovascular disease. However, patients who were overweight but not obese lived longer than those who were underweight or normal weight. The explanation for these results is unknown and does not mean that patients with diabetes should try to become overweight. Patients should continue to follow a healthy lifestyle.
Summaries for Patients are a service provided by Annals to help patients better understand the complicated and often mystifying language of modern medicine. Summaries for Patients are presented for informational purposes only. These summaries are not a substitute for advice from your own medical provider. If you have questions about this material, or need medical advice about your own health or situation, please contact your physician. The summaries may be reproduced for not-for-profit educational purposes only. Any other uses must be approved by the American College of Physicians.
Ann Intern Med. 2015;162:I-26. doi:10.7326/P15-9015
I-26 © 2015 American College of Physicians
Downloaded From: http://annals.org/ by a Welch Medical Library JHU User on 06/09/2015
