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Pulmonary Involvement in Obesity. ผศ.พญ. กนกพร อุดมอิทธิพงศ์ สาขาระบบหายใจและเวชบำบัดวิกฤต ภาควิชากุมารเวชศาสตร์ คณะแพทยศาสตร์ศิริราชพยาบาล. Definition of Obesity. (body mass index) BMI = weight (kg)/ height(m) 2 WHO classification of adult categories of BMI. Caucasian. Asia.
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Pulmonary Involvement in Obesity ผศ.พญ. กนกพร อุดมอิทธิพงศ์ สาขาระบบหายใจและเวชบำบัดวิกฤต ภาควิชากุมารเวชศาสตร์ คณะแพทยศาสตร์ศิริราชพยาบาล
Definition of Obesity (body mass index) BMI = weight (kg)/ height(m)2 WHO classification of adult categories of BMI Caucasian Asia Criteria and classification of obesity in Japan and Asia-Oceania Asia Pacific J Clin Nutr (2002) 11(Suppl): S732–S737
Definition of Obesity Children BMI percentile > 5th and < 85th = normal weight for height ≥ 85th and < 95th = at risk for overweight ≥ 95th = obese Weight for height ≥ 120th percentile = obesity ≥ 110th percentile < 120 = overweight
Trends in the prevalence of overweight Children’s ages (in years) Australia:2–18, Brazil: 6–18, Canada: 7–13, China: 6–18, Spain: 6–14, UK: 7–11, USA: 6–18. The International Association for the Study of Obesity. obesity reviews 5 (Suppl. 1), 4–85
การเปลี่ยนแปลงของเด็กไทยในรอบ 5 ปี % 36% 15.5% 5.8 7.9 5.8 6.7
Prevalence of obesity in Thai children การสำรวจโรงเรียน 342 โรงของเครือข่ายวิจัยสุขภาพ มูลนิธิสาธารณสุขแห่งชาติ พ.ศ. 2548 พบว่า • อ้วน ร้อยละ 12 ท้วม ร้อยละ 5 • กทม. อ้วน ร้อยละ 15.5 ท้วม ร้อยละ 7 รศ.พญ.ลัดดา เหมาะสุวรรณ
Complications of childhood obesity Childhood obesity: public-health crisis, common sense cure Lancet 2002, 360: 473–82
Pulmonary involvement in obesity: overview • Lung function in obesity • Asthma and obesity • Obstructive sleep apnea and obesity • Obesity hypoventilation syndrome • Postoperative pulmonary complications in obese patients
Lung function in obesity • Lung volume • FRC, ERV, TLC, VC, TV • RV • Lung mechanics • respiratory system compliance • work of breathing (WOB) • Flow limitation • FEV1 • Others: diffusion capacity (DLco) ventilation-perfusion mismatch O2 consumption and CO2 production
Obesity and asthma • Consistent association between obesity and asthma • Temporal association - Obesity precedes the development of asthma • Dose-response association - the greater the obesity, the greater the effect on asthma Obesity and asthma; AJRCC 2006: 174,112-9 Obesity and asthma: cause for concern; Curr Opin Pharm 2006,6: 230-6 Obesity and asthma, what are the link?; Curr Opin Allergy Clin Immunol 2005,5:185-93
Obesityandasthma :pathophysiology Obesity and Asthma, Am J Respir Crit Care Med 2006 ; 174. 112–119,
Obesity and asthma: pathophysiology Inflammatory factors Obesity and Asthma,Am J Respir Crit Care Med2006; 174. 112–119
Obesity and asthma: pathophysiology Mechanical factor Systemic inflammation Obesity Shared genetic factor Gender GERD
Obesity and asthma • Studies in children or adolescents • Inconsistent results in the asthma-obesity relation • No convincing evidence for a gender difference Prospective studies of obesity and asthma among paediatric patients Paediatric asthma and obesity, Paed Resp Rev 2006; 7, 233-8 Obesity and asthma; AJRCC 2006: 174,112-9
Obstructive Sleep Apnea (OSA)and Obesity • OSA : Disorder of breathing during sleep characterized by prolonged partial upper airway obstruction / intermittent complete obstruction that disrupts normal ventilation during sleep and normal sleep pattern . (ATS. AJRCC.1996; 153: 866-878) • Prevalence of OSA in obesity 37%- 46% • Correlation between degree of obesity and apnea index Mallory GB. et al. J Pediatr. 1989:115(6):892-7 Silvestri JM. et al. Ped Pulm. 1993;16(2):124-9 Marcus CL. et al. Ped Pul. 1996;21(3):176-83
OSA:History * Physical examination Polysomnography(PSG) Nighttime • snoring, labored breathing, • paradoxical breathing, • restless sleep, apnea, • cyanosis, enuresis Daytime • adenotonsillar hypertrophy, • mouth breathing • nasal obstruction • adenoid facies • systemic hypertention • prominent 2nd heart sound
OSA and obesity :pathophysiology OBESITY Abdominal and chest wall fat↑ Pharyngealfat ↑ Lung volumes↓ UA caliber↓ UA compliance↑ UA collapsibility ↑ OSAS Obesity and weight loss in obstructive sleep apnea: a critical review. Sleep 1996;19:104-115
OSA and obesity :pathophysiology • Increased pharyngeal fat • Increased chest wall and abdominal fat • Tonsil or adenoid enlargement • Shared genetic factors between OSA and obesity • Respiratory complications of obesity. Int J Clin Pract 2004;58:573-80. • Obesity and obstructive sleep apnea in children. Paediatr Respir Rev 2006;7:247-59. • Obstructive sleep apnea, morbid obesity, and adenotonsillar surgery: a review of the • literature. Int J Pediatr Otorhinolaryngol 2005;69:1475-82.
OSA and obesity: Treatment • Weight reduction • CPAP or BIPAP • Adenoidectomy and/or tonsillectomy Postoperative care in ICU • RDI ≥ 40 • RDI < 40 accompanied by desaturation nadir < 80% • Presence of cardiac sequelae from OSA Obstructive sleep apnea, morbid obesity, and adenotonsillar surgery. Int J Pediatr Otorhinolaryngol. 2005 Nov;69(11):1475-82
Obesity Hypoventilation Syndrome • Definition: Obesity and awake arterial hypercapnia (PaCO2 >45 mmHg) in the absence of other known causes of hypoventilation • Prevalence: 1-3% of obese children • Risk factor: morbid obesity
Obesity Hypoventilation Syndrome • Sleep-related breathing disorder • Hypersomnolence, fatigue • Morning headache • Hypoventilation: PaCO2>45 mmHg • Polycythemia • Cor pulmonale
Leptin Insensitivity ? Impaired Respiratory System Mechanics Increased Work of Breathing Increased Ventilatory Drive Normal or Diminished Ventilatory Drive Normal Ventilation, Eucapnia Hypoventilation, Hypercapnia Obstructive Sleep Apnea Severe Steep Hypoxemia Severe Steep Fragmentation Maintain Normal Ventilation Hypoventilation Hypercapnia Eucapnia The obesity hypoventilation syndrome. Am J Med 2005;118: 948
Obesity Hypoventilation Syndrome:treatment • Weight reduction • CPAP or BIPAP • Adenoidectomy and/or tonsillectomy Reversibility of hypercapnia to normal Obesity and obstructive sleep apnea in children. Paed resp rev. 2006; 7: 247
Postoperative pulmonary complications in obese patients • Atelectasis: obesity, anesthesia • Pulmonary embolism : severe obesity, OHS, decreased mobility • Respiratory failure Postoperative care • Closed monitoring • Early mobilization • Chest physiotherapy • Semiupright position Pulmonary complications of obesity. Am J Med sci 2001;321: 249
Pulmonary involvement in obesity OSA PFT OHS Asthma
PAEDIATRIC RESPIRATORY REVIEWS(2006) 7, 233-238Paediatric asthma and obesity Review of controlled trials on the benefits of exercise conditioning in paediatric in patients with asthma increased decreased ; unchanged; PWC peak word capacity at a heart rate of 170 beatsiminc, VO2, maximum oxygen consumption Vth, ventilatory threshold; H, healthy.
Comorbidities Related to Overweight in Youth Psychological Depression Poor quality of life Neurological Pseudotumor cerebri Hepatic Nonalcoholic fatty liver disease Nonalcoholic steatohepatitis Pulmonary Obstructive sleep apnea Asthma Central hypoventilation syndrome Renal Proteinuria Metabolic Type 2 DM Metabolic syndrome Orthopedic Slipped capital femoral epiphysis Blount’s disease Cardiovascular Dyslipidemia Hypertension Left ventricular hypertrophy Atherosclerosis
A Obesity B asthma • Tidal breathing FRC Tidal Breathing • Large cyclic strains on ASM Peribronchial pressure • ASM cells compliant • Small cyclic strains on ASM ASMcellsstiff • ASM cells long, airway caliber large ASM cells short, airway caliber narrowing
OSA • The increased prevalence and severity of childhood obesity has translated into increases in the prevalence of obesity-associated morbidities. • Among the multiple morbidities associated with obesity, OSA and OHS should be considered and evaluated. • The classic presentation of children with OSAS as underweight children with adenotonsillar hypertrophy is now being substantially replaced by patients being overweight. • Obese children are at increased risk for developing sleep-disordered breathing and the severity of OSAS is at least partially explained by the degree of obesity. • Obstructive sleep apnea may represent an important contributor to the association between obesity and metabolic and cardiovascular morbidities, by amplification of inflammatory cascades.
Obstructive sleep apnea and obesity:pathophysiology • Increased pharyngeal fat • Increased chest wall and abdominal fat • Tonsil or adenoid enlargement • Leptin resistance • Shared genetic factors between OSA and obesity • Respiratory complications of obesity. Int J Clin Pract 2004;58:573-80. • Obesity and obstructive sleep apnea in children. Paediatr Respir Rev 2006;7:247-59. • Obstructive sleep apnea, morbid obesity, and adenotonsillar surgery: a review of the • literature. Int J Pediatr Otorhinolaryngol 2005;69:1475-82.
Obesity Hypoventilation Syndrome Obesity Leptin > Leptin- resistance Hypercapnia Leptin Leptin- resistance Apneas (intermitent Hypoxemia) Increases in Visceral fat OSA predisposition
Inflammatory factors Figure 1. In obesity, visceral adiposity is correlated with circulating levels of proinflammatory cytokines, and adipose tissue propagates inflammation both locally and systemically, in part through recruitment of macrophages via chemokines such as monocyte chemoattractant protein-1 (MCP-1) and in part via elaboration of cytokines and chemokines such as (but not limited to) leptin, interleukin 6 (IL-6), tumor necrosis factor (TNF-), transforming growth factor 1 (TGF-1), and eotaxin. Although the precise relationship between obesity and asthma remains to be determined, modifications of atopy, lung development, Th1–Th2 balance, immune responsiveness, and airway smooth muscle have been hypothesized to be mechanisms by which obesity might increase asthma risk or modify asthma phenotype. CRP C-reactive protein. Obesity and Asthma,David A. Beuther, Scott T. Weiss, and E. Rand Sutherland Am J Respir Crit Care Med Vol 174. pp 112–119, 2006