Journal of the American Society of Hypertension 9(8) (2015) 584–585
Commentary
Cardiovascular risk factors in severely obese adolescents Stefan Engeli, MD* Hannover Medical School, Institute of Clinical Pharmacology, Hannover, Germany Manuscript received May 7, 2015 and accepted May 9, 2015
High body weight increases the incidence for a plethora of metabolic, cardiovascular, orthopedic and mental conditions. The longer a patient lives with these conditions, the greater is the likelihood for a severe disease to develop. Consequently, obese children and adolescents represent a highly vulnerable group of patients because most obese children will grow up to become even more obese adults.1 Comparable to adults, current preventive measures and lifestyle interventions to reduce body weight were only modestly effective and will not provide a solution in the long-term.2,3 The more drastic interventional approach of bariatric surgery has thus become a reasonable and increasingly used therapeutic option in adolescents. Guidelines from the International Pediatric Endosurgery Group suggest the following indications for adolescents: BMI >40 kg/m2 or >35 kg/m2 when accompanied by severe comorbidities and nearly attained adult stature.4 Surgical techniques and experience have improved significantly over the last years, so that indication criteria have become broader, and procedure numbers in adolescents are rapidly increasing, for example in Germany an 8-fold increase between 2005 and 2010 was reported.5 In the meantime we learned a lot about immediate perioperative risk that ranges between 2% and 7% depending on the surgical technique and decreases with experience.5,6 We also know a lot about weight changes during the first 2-3 years. Again, different procedures yield different results, gastric banding leads to a mean BMI reduction of about 9 kg/m2, whereas gastric bypass and sleeve gastrectomy operations are more effective and decrease BMI by 14-16 kg/m2.5,6 However, long-term outcome data are scarce, and of course we do not know yet whether adolescent gastric surgery is able to reduce the number of massively obese young adults who experience stigmatization, extremely impaired job possibilities and who suffer from diabetes and early cardiovascular disease.7,8 Skepticism against the procedure may be raised given the lack of long-term outcome data. Therefore, a closer look at the comorbidities of adolescents scheduled for bariatric *Corresponding author: Stefan Engeli, MD, Institute of Clinical Pharmacology, Hannover Medical School, Carl-NeubergStrasse 1, 30625 Hannover, Germany. Tel: þ49 511 532 2796; Fax: þ49 511 532 2750. E-mail: [email protected]
surgery might help to understand the medical necessity of the approach. The Teen Longitudinal Assessment of Bariatric Surgery (Teen-LABS) Study is a prospective cohort study that enrolled 242 consecutive patients 19 years or younger between February 2007 and December 2011 in five centers in the U.S. The predominant procedure was gastric bypass (66%), whereas sleeve gastrectomy (28%) and gastric banding (6%) were done less often. Mean age of participants was 17 years and mean BMI 50.5 kg/m2. 73% were women, 72% white, and 93% non-hispanic. Perioperative risk was comparable to other reports, within 30 days after surgery major complications occurred in 19 patients, and minor complications occurred in 36%.9 Analyzing this cohort, a recent report in JAMA Pediatrics described the prevalence of cardiovascular risk factors.10 Only 5% of the patients were free of any cardiovascular risk factor, but fasting hyperinsulinemia (74%), elevated C-reactive protein (75%), dyslipidemia (50%, mostly elevated triglycerides and decreased HDL cholesterol), hypertension (49%, diagnosed by prescription of antihypertensive drugs) and impaired fasting glucose (26%) occurred with high prevalence. Compared to the obese cohort NHANES data, adolescents undergoing bariatric surgery are significantly heavier, and the prevalence of elevated blood pressure and low HDL is much higher.10 The clustering of risk factors at age 17 is impressive, 61% presented with at least 2 risk factors. Despite the already high prevalence of hypertension in the BMI 3050 kg/m2 group (39%), rising BMI further increased the prevalence of hypertension (57% with BMI 50-60; 61% with BMI > 60). For every 5 BMI points increase, the hypertension risk increased by 10%. The graded effect of BMI on hypertension is mirrored by a similar development of the impaired fasting glucose prevalence, whereas other risk factors have already reached a maximum in the BMI 3050 kg/m2 group. These findings on elevated blood pressure might well be associated with the high prevalence of obstructive sleep apnea (57%), a condition that raises sympathetic nerve activity and contributes to blood pressure elevation. Prevalence of cardiovascular risk factors in his report may be biased by patient selection in terms of sex and ethnicity. Males had a higher prevalence of hypertension
1933-1711/$ - see front matter Ó 2015 American Society of Hypertension. All rights reserved. http://dx.doi.org/10.1016/j.jash.2015.05.007
S. Engeli / Journal of the American Society of Hypertension 9(8) (2015) 584–585
but are a minority in the study cohort; non-whites had a higher risk of impaired fasting glucose, but are a minority in the study cohort. Moreover, the fact that medical help was requested and a decision towards bariatric surgery was made may suggest that patients were less healthy than other adolescents of the same weight. Thus, the true prevalence of the reported cardiovascular risk factors may be smaller. Nevertheless, patients enrolled in the TeenLABS study are severely affected by their body weight and there is tremendous hope that bariatric surgery at that early time in life will do what no other treatment option could provide. The long-term outcome data of the TeenLABS study are highly anticipated. In the meantime, performing bariatric surgery in adolescents appears to be a meaningful approach when accepted indications are followed (see above) and post-surgical care according to current guidelines can be provided.4,11 Moreover, if patients are not included in clinical studies, immediate postsurgical as well as long-term outcome need to be recorded in registries in as many cases as possible. Outcome measures should not be limited to weight changes but should also include comorbidities and psycho-social variables (eg stigmatization, education, career chances).
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References 1. McCrindle BW. Cardiovascular consequences of childhood obesity. Can J Cardiol 2015;31:124–30. 2. Peirson L, Fitzpatrick-Lewis D, Morrison K, Ciliska D, Kenny M, Usman Ali M, et al. Prevention of overweight and obesity in children and youth: a systematic review and meta-analysis. CMAJ Open 2015;3:E23–33. 3. Peirson L, Fitzpatrick-Lewis D, Morrison K, Warren R, Usman Ali M, Raina P. Treatment of overweight and obesity in children and youth: a systematic review and meta-analysis. CMAJ Open 2015;3:E35–46. 4. International Pediatric Endosurgery G. IPEG guidelines for surgical treatment of extremely obese adolescents.
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11.
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J Laparoendosc Adv Surg Tech A 2009;19(Suppl 1): xiv–xvi. Lennerz BS, Wabitsch M, Lippert H, Wolff S, Knoll C, Weiner R, et al. Bariatric surgery in adolescents and young adults–safety and effectiveness in a cohort of 345 patients. Int J Obes 2014;38:334–40. Paulus GF, de Vaan LE, Verdam FJ, Bouvy ND, Ambergen TA, van Heurn LW. Bariatric surgery in morbidly obese adolescents: a systematic review and meta-analysis. Obes Surg 2015;25:860–78. Wabitsch M, Moss A, Reinehr T, Wiegand S, Kiess W, Scherag A, et al. Medical and psychosocial implications of adolescent extreme obesity - acceptance and effects of structured care, short: Youth with Extreme Obesity Study (YES). BMC Public Health 2013;13:789. Britz B, Siegfried W, Ziegler A, Lamertz C, HerpertzDahlmann BM, Remschmidt H, et al. Rates of psychiatric disorders in a clinical study group of adolescents with extreme obesity and in obese adolescents ascertained via a population based study. Int J Obes 2000; 24:1707–14. Inge TH, Zeller MH, Jenkins TM, Helmrath M, Brandt ML, Michalsky MP, et al., Teen-LABS Consortium. Perioperative outcomes of adolescents undergoing bariatric surgery: the Teen-Longitudinal Assessment of Bariatric Surgery (Teen-LABS) study. JAMA Pediatr 2014;168:47–53. Michalsky MP, Inge TH, Simmons M, Jenkins TM, Buncher R, Helmrath M, et al., For the Teen-LABS Consortium. Cardiovascular Risk Factors in Severely Obese Adolescents: The Teen Longitudinal Assessment of Bariatric Surgery (Teen-LABS) Study. JAMA Pediatr 2015;169:438–44. Fried M, Yumuk V, Oppert JM, Scopinaro N, Torres AJ, Weiner R, et al. European Association for the Study of Obesity; International Federation for the Surgery of Obesity - European Chapter. Interdisciplinary European Guidelines on metabolic and bariatric surgery. Obes Facts 2013;6:449–68.
Commentary
Cardiovascular risk factors in severely obese adolescents Stefan Engeli, MD* Hannover Medical School, Institute of Clinical Pharmacology, Hannover, Germany Manuscript received May 7, 2015 and accepted May 9, 2015
High body weight increases the incidence for a plethora of metabolic, cardiovascular, orthopedic and mental conditions. The longer a patient lives with these conditions, the greater is the likelihood for a severe disease to develop. Consequently, obese children and adolescents represent a highly vulnerable group of patients because most obese children will grow up to become even more obese adults.1 Comparable to adults, current preventive measures and lifestyle interventions to reduce body weight were only modestly effective and will not provide a solution in the long-term.2,3 The more drastic interventional approach of bariatric surgery has thus become a reasonable and increasingly used therapeutic option in adolescents. Guidelines from the International Pediatric Endosurgery Group suggest the following indications for adolescents: BMI >40 kg/m2 or >35 kg/m2 when accompanied by severe comorbidities and nearly attained adult stature.4 Surgical techniques and experience have improved significantly over the last years, so that indication criteria have become broader, and procedure numbers in adolescents are rapidly increasing, for example in Germany an 8-fold increase between 2005 and 2010 was reported.5 In the meantime we learned a lot about immediate perioperative risk that ranges between 2% and 7% depending on the surgical technique and decreases with experience.5,6 We also know a lot about weight changes during the first 2-3 years. Again, different procedures yield different results, gastric banding leads to a mean BMI reduction of about 9 kg/m2, whereas gastric bypass and sleeve gastrectomy operations are more effective and decrease BMI by 14-16 kg/m2.5,6 However, long-term outcome data are scarce, and of course we do not know yet whether adolescent gastric surgery is able to reduce the number of massively obese young adults who experience stigmatization, extremely impaired job possibilities and who suffer from diabetes and early cardiovascular disease.7,8 Skepticism against the procedure may be raised given the lack of long-term outcome data. Therefore, a closer look at the comorbidities of adolescents scheduled for bariatric *Corresponding author: Stefan Engeli, MD, Institute of Clinical Pharmacology, Hannover Medical School, Carl-NeubergStrasse 1, 30625 Hannover, Germany. Tel: þ49 511 532 2796; Fax: þ49 511 532 2750. E-mail: [email protected]
surgery might help to understand the medical necessity of the approach. The Teen Longitudinal Assessment of Bariatric Surgery (Teen-LABS) Study is a prospective cohort study that enrolled 242 consecutive patients 19 years or younger between February 2007 and December 2011 in five centers in the U.S. The predominant procedure was gastric bypass (66%), whereas sleeve gastrectomy (28%) and gastric banding (6%) were done less often. Mean age of participants was 17 years and mean BMI 50.5 kg/m2. 73% were women, 72% white, and 93% non-hispanic. Perioperative risk was comparable to other reports, within 30 days after surgery major complications occurred in 19 patients, and minor complications occurred in 36%.9 Analyzing this cohort, a recent report in JAMA Pediatrics described the prevalence of cardiovascular risk factors.10 Only 5% of the patients were free of any cardiovascular risk factor, but fasting hyperinsulinemia (74%), elevated C-reactive protein (75%), dyslipidemia (50%, mostly elevated triglycerides and decreased HDL cholesterol), hypertension (49%, diagnosed by prescription of antihypertensive drugs) and impaired fasting glucose (26%) occurred with high prevalence. Compared to the obese cohort NHANES data, adolescents undergoing bariatric surgery are significantly heavier, and the prevalence of elevated blood pressure and low HDL is much higher.10 The clustering of risk factors at age 17 is impressive, 61% presented with at least 2 risk factors. Despite the already high prevalence of hypertension in the BMI 3050 kg/m2 group (39%), rising BMI further increased the prevalence of hypertension (57% with BMI 50-60; 61% with BMI > 60). For every 5 BMI points increase, the hypertension risk increased by 10%. The graded effect of BMI on hypertension is mirrored by a similar development of the impaired fasting glucose prevalence, whereas other risk factors have already reached a maximum in the BMI 3050 kg/m2 group. These findings on elevated blood pressure might well be associated with the high prevalence of obstructive sleep apnea (57%), a condition that raises sympathetic nerve activity and contributes to blood pressure elevation. Prevalence of cardiovascular risk factors in his report may be biased by patient selection in terms of sex and ethnicity. Males had a higher prevalence of hypertension
1933-1711/$ - see front matter Ó 2015 American Society of Hypertension. All rights reserved. http://dx.doi.org/10.1016/j.jash.2015.05.007
S. Engeli / Journal of the American Society of Hypertension 9(8) (2015) 584–585
but are a minority in the study cohort; non-whites had a higher risk of impaired fasting glucose, but are a minority in the study cohort. Moreover, the fact that medical help was requested and a decision towards bariatric surgery was made may suggest that patients were less healthy than other adolescents of the same weight. Thus, the true prevalence of the reported cardiovascular risk factors may be smaller. Nevertheless, patients enrolled in the TeenLABS study are severely affected by their body weight and there is tremendous hope that bariatric surgery at that early time in life will do what no other treatment option could provide. The long-term outcome data of the TeenLABS study are highly anticipated. In the meantime, performing bariatric surgery in adolescents appears to be a meaningful approach when accepted indications are followed (see above) and post-surgical care according to current guidelines can be provided.4,11 Moreover, if patients are not included in clinical studies, immediate postsurgical as well as long-term outcome need to be recorded in registries in as many cases as possible. Outcome measures should not be limited to weight changes but should also include comorbidities and psycho-social variables (eg stigmatization, education, career chances).
5.
6.
7.
8.
9.
References 1. McCrindle BW. Cardiovascular consequences of childhood obesity. Can J Cardiol 2015;31:124–30. 2. Peirson L, Fitzpatrick-Lewis D, Morrison K, Ciliska D, Kenny M, Usman Ali M, et al. Prevention of overweight and obesity in children and youth: a systematic review and meta-analysis. CMAJ Open 2015;3:E23–33. 3. Peirson L, Fitzpatrick-Lewis D, Morrison K, Warren R, Usman Ali M, Raina P. Treatment of overweight and obesity in children and youth: a systematic review and meta-analysis. CMAJ Open 2015;3:E35–46. 4. International Pediatric Endosurgery G. IPEG guidelines for surgical treatment of extremely obese adolescents.
10.
11.
585
J Laparoendosc Adv Surg Tech A 2009;19(Suppl 1): xiv–xvi. Lennerz BS, Wabitsch M, Lippert H, Wolff S, Knoll C, Weiner R, et al. Bariatric surgery in adolescents and young adults–safety and effectiveness in a cohort of 345 patients. Int J Obes 2014;38:334–40. Paulus GF, de Vaan LE, Verdam FJ, Bouvy ND, Ambergen TA, van Heurn LW. Bariatric surgery in morbidly obese adolescents: a systematic review and meta-analysis. Obes Surg 2015;25:860–78. Wabitsch M, Moss A, Reinehr T, Wiegand S, Kiess W, Scherag A, et al. Medical and psychosocial implications of adolescent extreme obesity - acceptance and effects of structured care, short: Youth with Extreme Obesity Study (YES). BMC Public Health 2013;13:789. Britz B, Siegfried W, Ziegler A, Lamertz C, HerpertzDahlmann BM, Remschmidt H, et al. Rates of psychiatric disorders in a clinical study group of adolescents with extreme obesity and in obese adolescents ascertained via a population based study. Int J Obes 2000; 24:1707–14. Inge TH, Zeller MH, Jenkins TM, Helmrath M, Brandt ML, Michalsky MP, et al., Teen-LABS Consortium. Perioperative outcomes of adolescents undergoing bariatric surgery: the Teen-Longitudinal Assessment of Bariatric Surgery (Teen-LABS) study. JAMA Pediatr 2014;168:47–53. Michalsky MP, Inge TH, Simmons M, Jenkins TM, Buncher R, Helmrath M, et al., For the Teen-LABS Consortium. Cardiovascular Risk Factors in Severely Obese Adolescents: The Teen Longitudinal Assessment of Bariatric Surgery (Teen-LABS) Study. JAMA Pediatr 2015;169:438–44. Fried M, Yumuk V, Oppert JM, Scopinaro N, Torres AJ, Weiner R, et al. European Association for the Study of Obesity; International Federation for the Surgery of Obesity - European Chapter. Interdisciplinary European Guidelines on metabolic and bariatric surgery. Obes Facts 2013;6:449–68.
