Women & Addiction: Why is it more difficult for women to quit smoking? Nora D. Volkow, M.D. Director National Institute on Drug Abuse National Institutes of Health Natural & Drug Reinforcers Increase Dopamine in NAc NICOTINE % of Basal Release 250 frontal cortex nucleus accumbens 200 Accumbens 150 100 0 1 0 VTA/SN 2 Time After Nicotine FOOD % of Basal Release 200 Drugs of abuse increase DA in the Nucleus Accumbens, which is believed to trigger the neuroadaptions that result in addiction 3 hr Accumbens 150 100 50 0 Empty Box Feeding 0 60 120 180 Time (min) Di Chiara et al. Long term effects of nicotine differs in males and females and this is influenced by age Prevalence Rate Smokers: Men -- 25.4% Women -- 20.7% 2010 National Survey on Drug Use & Health (NSDUH), SAMHSA, 2011. Menopause Menarche Tobacco Addiction is a Developmental Disease that Starts in Adolescence and Earlier in Girls than Boys 17.5 % in each age group who develop first time dependence 1.8% 17 1.6% 16.5 1.4% 16 Male Female 15.5 1.2% 15 1.0% 14.5 0.8% 14 Onset of Daily Smoking White et al. (2002) 0.6% 0.4% 0.2% 0.0% 5 10 15 21 25 30 35 40 45 50 55 60 65 Age Age at tobaccouse dependence as per DSM IV NIAAA National Epidemiologic Survey on Alcohol and Related Conditions, 2003. Time from onset to dependence: Girls: 3 weeks Boys: 6 months DiFranza et al. (2002) Rates of Cotinine Clearance Rates of Nicotine Clearance (ml/min/kg) (ml/min/kg) * * * * * * OC: oral contraceptives Benowitz et al., 2006, Clin Pharm Ther Nicotine: More than Dopamine Aromatase* (Estrogen synthase, CYP19A1) C H3 O H CH3 O H CH3 aromatase HO O testosterone • 17 b -estradiol Mediates sexual differentiation of the brain during development (Wu et al., Cell 2009) Acute nicotine inhibits aromatase in the Brain (Biegon et al., Biological Psychiatry , 2010) Baseline 0.015 mg/kg 0.03 mg/kg Smoking has Adverse Effects on Womens’ Endocrinology and Reproductive Health • • • • • Female smokers show hypo-estrogenic effects including early menopause, dysmenorrhea, menstrual irregularity Lower bone mineral density (osteoporosis) Conception delay, primary/secondary infertility Pregnancy & delivery complications Stillborn, neonatal death Surgeon General’s Report 2001, Women & Smoking Smoking During Pregnancy… • Affects prenatal and postnatal growth • Increases the risk of developmental and behavioral deficits Use of Drugs During Pregnancy Not Only Affects the Physiology of the Mother But Also that of the Fetus Nicotine Gets into the Fetus’ Brain Nicotine gets into the fetal brain [11C]Nicotine and metabolites Placenta Fetal brain Maternal Brain Fetal brain Fetal Liver Source: Benveniste et al. Unpublished data Effect of Secondhand Smoke on Occupancy of Nicotinic Acetylcholine Receptors in Brain Control Second Hand Smoke Secondhand smoke (SHS) exposure decreased 2-FA binding in brain demonstrating α4β2* nicotinic acetylcholine receptor occupancy Secondhand smoke (SHS) leads to significant α4β2* nicotinic acetylcholine receptor occupancy (18-22%) Brody et al. Arch General Psych 2011. Second Hand Smoke (SHS) Exposure • • • Increases risk of pregnancy complications and affects fetal health Worldwide, 50% of men smoke and particularly in developing countries, there are few proscriptions against smoking in the home Children exposed to SHS have increased risk of: -- Sudden Infant Death Syndrome -- Lower respiratory tract infections -- Ear infections -- Asthma -- Becoming smokers Women have a harder time quitting… • Factors control smoking -- Women are less sensitive to nicotine as a pharmacologic agent -- Women are more sensitive to non-nicotine factors • Greater role in women -- stress & negative affect -- depression -- weight concerns The Smoker’s Body Smokers have a 35-45% reduction in MAO B in heart, lungs, kidneys and spleen As Women Age, the Medical Consequences from Smoking are Greater than for Males Lung cancer risk is 2 x greater in women than in men; women develop lung cancer with less time than men Heart attacks relative risk for smokers vs non-smokers Men: 1.43 -- Women: 2.24 Breast cancer risk dose-dependently increases with exposure risk of breast cancer spreading to lungs is 2x than in nonsmokers Smoking Causes Cancer in Organs Throughout the Body Throat Larynx (voice box) Mouth Esophagus Lung Leukemia (blood) Stomach Kidney Bladder Pancreas Cervix Clinical Implications • Less attention to NRTs (except the inhaler) • More attention to • CBT to deal with the non-nicotine aspects of smoking -- environmental cues, mood • Cognitive restructuring regarding risks -- weight gain • Non-NRT pharmacotherapies -- bupropion: M=F; F only with CYP2BG polymorphism -- varenicline: M=F -- naltrexone: effective only in F • Menstrual cycle