TOBACCO AND OTHER METABOLIC DISORDERS MiniLecture 2 Module

TOBACCO AND OTHER METABOLIC DISORDERS Mini-Lecture 2 Module: Tobacco and Endocrine Problems

Objectives of the Mini Lecture Goal of Mini-Lecture: Provide students with knowledge of how tobacco affects metabolic disorders other than diabetes Learning Objectives: Student will be able to: • Discuss the association between tobacco use and obesity and dyslipidemia. • Advise smoking cessation for patients and populations with other CVD risk factors, i. e. obesity and dyslipidemia.

Contents Core Slides: Optional Slides: 1. 2. 3. 4. 5. 6. 7. 8. 9. Smoking and Metabolic Disorders Smoking and Insulin Resistance Body Fat Distribution in Smoking and Changes in Lipid Profile Smoking and HDL Centripetal Adiposity Smoking and Obesity: Mortality Smoking Cessation and Weight Gain What Should Doctors Do? 2. 3. 4. 5. Smoking, Weight Gain, and Women Lipid Profile Changes: Pathways Role of Plasma FFAs Smoking and LDL Oxidation Smoking and Free Radicals

CORE SLIDES TOBACCO AND ENDOCRINE PROBLEMS Mini-Lecture 2 Module: Tobacco and Endocrine Problems

Smoking and Metabolic Disorders • Metabolic syndrome is more prevalent in active smokers than in those who are exposed to secondhand smoke or those who have no exposure. 1 • Smoking cessation should be advised to all patients who smoke who have metabolic disorders and/or dyslipidemia. 2 1. Chiolero et al. 2008; 2. Erhardt 2009

Smoking and Insulin Resistance • Smoking has direct and indirect effects on increasing insulin resistance. • Smoking can lead to accumulation of visceral fat, which increases insulin resistance. • Most smokers exhibit insulin resistance syndromes. 1 • Cigarette smoking leads to reduced insulin sensitivity, decreased glucose utilization, and reduction in insulin receptor affinity. 2 1. Chiolero et al. , 2008; 2. Berlin 2008

Body Fat Distribution in Smokers 1 • Decreased body mass index, increased waist circumference, and decreased hip circumference. • Increased metabolic rate (i. e. increased energy expenditure and decreased metabolic efficiency). • Acute anorexic effect → decreased caloric absorption. 1. Chiolero et al. 2008

Smoking and Changes in Lipid Profile • Increased total plasma cholesterol, increased plasma triglycerides and decreased HDL cholesterol → leads to development of plaque • Smoking also increased lipid peroxidation → increased levels of Ox. LDLC (oxidized LDL-C) 1. Berlin 2008; 2. Erhardt 2009 http: //z. about. com/f/p/440/graphics/images/en/19289. jpg

Smoking and HDL • Plasma HDL levels reduced in adults, adolescents, and children 1, 2 • HDL protein structure modified by cross-linking apo A 1 and A 21 • Interrupts reverse cholesterol transport pathway • Impairs HDL mediated movement of cholesterol across cell membranes 1. Mc. Call et al. 1994; 2. Neufeld et al. 1997 http: //www. phillips-fit. co. uk/pfiles/images/HDL%20 LDL. jpg

Centripetal Adiposity • Abdominal fat accumulation 1: • High levels of plasma cortisol • Increased testosterone concentration • Increased accumulation of adipose tissue in abdomen compared to femoralgluteal area 2 1. Chiolero et al. 2008; 2. Troisi et al. 1991 http: //musicforchange. com/cms/images/rapid_weight_loss. jpg

Smoking and Obesity: Mortality • Compared to normal weight never smokers, obese current smokers have 1: • 3. 5 to 5 times higher risk of all-cause mortality • 6 to 11 times higher risk of cardiovascular mortality (among those less than 65 years old) • The associated risk of cardiovascular mortality among former smokers is significantly lower (about 4 times). 1. Freedman et al. 2006

Smoking Cessation and Weight Gain • Smoking cessation results in weight gain but less upper-body fat deposition 1, 2 • Upper body fat distribution in women puts them at higher risk for CAD, stroke, diabetes and unfavorable lipid profiles than generalized obesity 1 • No evidence of large or steady weight gain 2 1. Lissner et al. 1992; 2. Gruber et al. 2006 http: //conservativehome. blogs. com/torydiary/images/2007/10/18/barrie_free 2 bme. gif

What Should a Doctor Do? • Explain that smoking worsens lipid profile and increased risk of cardiovascular/ atherosclerotic diseases • Any patient with unfavorable lipids or centripetal obesity: advise to quit smoking http: //media. counton 2. com/wcbd/gfx. php? max_width=300 andimgfile=images/uploads/MEDICAL_SIGN_ON_BACKGROUND. JPG

OPTIONAL SLIDES TOBACCO AND ENDOCRINE PROBLEMS Mini-Lecture 2 Module: Tobacco and Endocrine Problems

Smoking, Weight Gain, and Women Studies in high-income countries found that : • Women viewed smoking as a weight control tool (39%)1 • Women smokers made fewer attempts to quit smoking when compared to men due to fear of ensuing weight gain 2 • Weight gain and increased appetite: reasons for relapse 1 1. Lissner et al. 1992; 2. Gruber et al. 2006 http: //obesitynews. com. au/wp-content/uploads/2009/05/fat-smoker-drinker-300 x 292. jpg

Lipid Profile Changes: Pathways • Inhibits lecithin cholesterol acyl transferase (LCAT) activity 1 • Increases levels of cholesteryl ester transfer protein (CETP) activity 2 • Smoking releases catecholamines: increases plasma free fatty acids (FFA)3 • Inhibits and decreases serum paraoxonase activity: increases LDL oxidation by arterial wall myeloperoxidases and lipoxygenases 3 http: //www. theheart. org/display. Item. do? primary. Key=113939 andtype=img 1. Mc. Call et al. 1994; 2. Dullaart et al. 1994; 3. Tsiara et al. 2003

Role of Plasma FFAs 1 • Smoking releases catecholamines increases plasma free fatty acid (FFA) concentration • Stimulates myocardial oxygen consumption • Decreases PGI 2 synthesis and bioavailability enhances atherogenesis • Increases arterial blood pressure • Adversely affects endothelial structure • Adversely affects endogenous, endothelium dependent, platelet inhibitor system – adenosine diphosphatase (ADPase) 1. Tsiara et al. 2003

Smoking and LDL Oxidation • Cigarette smoke exposure produces oxidized low-density lipoprotein (ox. LDL) accumulation of cholesteryl esters in macrophages 1 • Cigarette smoke inhibits and decreases serum paraoxonase activity diminishes its capacity to protect LDL from oxidation 2 • Stimulates arterial wall monocyte infiltration, adhesion, and migration into the sub-intimal space and smooth muscle cell proliferation 2 induces foam cell formation and atherosclerosis 1 • Induces apoptosis of the endothelial cells and atherosclerotic plaque erosion 2 • Increases levels of TNF-α and C-Reactive Protein 2 • Smoking cessation reduces the susceptibility of LDL to oxidation 2 1. Craig et al. 1990; 2. Tsiara et al. 2003

Smoking and Free Radicals 1 • Smoking induces free radical generation • Free radicals enhance atherogenic effect of lipid peroxidation induces endothelial dysfunction and increases incidence of vascular events • Antioxidants – vitamin C and α-tocopherol: provide protection against LDL oxidation • Smoking associated with low dietary vitamin intake, altered metabolism, and decreased serum concentrations of antioxidant vitamins • Smokers of both genders lower serum vitamin C and β-carotene 1. Tsiara et al. 2003

The most important health message a doctor can give to patients is to quit smoking.