Epidemiological Studies on Environmental Stressors from Tobacco to Pesticides

Transcription

1 Epidemiological Studies on Environmental Stressors from Tobacco to Pesticides W. Susan Cheng, PhD, MPH Rebecca Carlstrom, MPH Sukaina Hussain, MPH Healthy Lawn Symposium Oct 31, 2014

2 Two Presentations Allergies, Asthma, and Environmental Stressors By Dr. Susan Cheng, PhD, MPH Tobacco-Free Campus Research Study and Initiative By Rebecca Carlstrom, MPH & Sukaina Hussain, MPH

3 Effects of Pesticides on Health (especially Asthma) W. Susan Cheng, PhD, MPH Master of Public Health Department

4 Effects of Pesticides on Health Pesticide exposure has been shown to be correlated to: Cancer (leukemia, non-hodgkin s lymphoma) Birth defects (cleft palate, limb reduction) Endocrine disruption (fertility issues, endometriosis) Neurological disorders (dizzy, lightheaded, confused) Weakened immune system/response Asthma (can trigger, initiate, or exacerbate)

5 Asthma Asthma is an inflammatory disease of the lung... Once considered a minor ailment affecting only a small portion of the population, asthma is now the most common chronic disorder of childhood. Sources: National Heart Lung and Blood Institute, National Institutes of Health

6 Asthma Environmental and genetic links Familial link or atopy Inherited tendency for allergies Triggered by allergens Exposure in early childhood: Viral infection or allergen Once triggered, inflammation occurs in airways, compromising breathing Sources: National Heart Lung and Blood Institute, National Institutes of Health

7 Signs and Symptoms of Asthma Recurring periods of wheezing Chest tightness Shortness of breath Coughing Sources: National Heart Lung and Blood Institute, National Institutes of Health

8 Treatment of Asthma Avoiding environmental triggers Asthma Action Plan Medications (preventive) Inhaled Corticosteroids Antihistamines Rescue medications Albuterol Steroids Sources: National Heart Lung and Blood Institute, National Institutes of Health

9 Epidemiology of Asthma 25 million people with known asthma in the US (1 in 12) ½ have asthma attacks every year $58 Billion approximate annual costs Medical care, lost school and work days, early deaths 9 people die daily from asthma attacks

10 Epidemiology of Asthma 6.2 million children under 18 years old have asthma More prevalent among boys than girls among children Among adults, more women than men have asthma Majority of patients with asthma have allergies Children can outgrow allergies after 6 years old Increased risk for lifelong asthma with allergies, eczema, or parents/familial link with asthma

11 Epidemiology of Asthma Asthma is increasing in incidence: From , # diagnosed increased by 4.3 million ppl African-American children increased by 50% Roughly 1 in 9 African Americans, and 1 in 6 AA children have asthma Estimated 50 million Americans have allergies Over half of asthmatics have allergies too

12 Environmental Triggers for Asthma Occupational asthma triggered by chemical irritants or industrial dust Environmental asthma tobacco smoke air pollution chemicals or dust in the workplace compounds in home products aerosol sprays (e.g. hair sprays)

13 Tobacco Smoke and Asthma International Study of Asthma and Allergies in Childhood (ISAAC) surveyed 3000 adolescents aged yo Smokers twice as likely to have asthma or rhinitis Boys more likely than girls M Gomez, et al. Adolescent smokers are at greater risk for current asthma and rhinitis. Int J Tuberc Lung Dis. 13 (8): , 2009.

14 Pesticides and Asthma Pesticides can trigger asthma attacks, especially in children More susceptible (children breath in more air than adults, relatively) More direct contact with lawns and shrubs/greens More repeated (chronic) contact with pesticides in yards Source: A Glaser. Asthma, Children and Pesticides. National Coalition Against the Misuse of Pesticides. Vol 25, No 2, 2005.

15 Pesticides and Asthma Pesticides can trigger hypersensitivity in airways, making them more susceptible to an asthma attack at subsequent exposure to pesticides Johns Hopkins researchers hypothesize that pesticides alter the nerve function controlling the smooth muscle lining of the airway, causing the airway to contract and restrain airflow and thus an asthmatic attack 27 of the 30 most common lawn pesticides are irritants or stimulate hypersensitivity in the airways; may trigger or exacerbate asthma in children Source: A Glaser. Asthma, Children and Pesticides. National Coalition Against the Misuse of Pesticides. Vol 25, No 2, 2005.

16 Pesticides and Asthma Studies In 2003, a study of 3,000 Lebanese children reported correlation between home and garden pesticide exposure, proximity to a treated agricultural field, or occupation use by a family member with asthma In 2004, a study of 4,000+ school aged children in CA found that exposure to herbicides in the 1 st year of life increases risk 4.5 times of developing asthma by age 5 Toddlers and young infants are at much greater risk MT Salem, et al. Early life environmental risk factors for asthma: findings from the children s healthy study. Environ Health Perspect 2003; 112: JD Thrasher, et al. Immunologic abnormalities in humans exposed to chlorpyrifos: preliminary observations. Arch Environ Med 1993; 48:89-93.

17 Pesticides and Asthma Studies In Spain, a study of 405 children ages newborn to 14 years old reported on a subset of 275 children at age 4 and reported that evidence of pesticides in the blood was associated with wheezing Looked specifically at DDT and HCB persistent organic pollutants Although these substances were banned in the 70 s, many still evident in soil samples and bioaccumulate in children who have increased contact M Gascon et al. Persistent organic pollutants and children s respiratory health: The role of cytokines and inflammatory biomarkers. Environment International. 2014; 69:

18 Pesticides and Asthma Studies Cord blood study of 2,050 infants found levels of pesticides in blood associated with allergies & eczema; children with higher levels of pesticides in their blood are at increased risk of asthma (strong, positive association) In Mexico, cord blood from 613 infants were analyzed for presence of pesticides and IgE levels (marker for allergic response); pesticides were associated with higher IgE levels in the infants. Exposure to insecticides, herbicides, and fungicides have all been shown to be correlated with higher rates of asthma W. Karmaus, et al. Infections an datopic disorders in childhood and organochlorine exposure. Arch Environ Health 2001; 56: E Hernandez et al. Prenatal determinants of cord blood total immunoglobulin E levels in Mexican newborns.

19 Some Good News Microbiome diversity may decrease risk of asthma and allergies in children Two studies follow: Diversity of microbiome Early exposure to bacteria

20 Dust in Homes with Dogs May Protect Against Allergies, Asthma Previous study: infants in homes with dogs have lower risk of developing childhood allergies Dog-associated house dust decreases allergic inflammation (asthma) Dust collect wide diversity of bacteria from dogs Toddlers are exposed to a wider variety of bacteria from this household dust from the dogs Increases the biodiversity of the toddlers microbiome Lactobacillus johnsonii could potentially prevent airway inflammation (asthma) from exposure to allergens or RSV infection KE Fujimura et al. House dust exposure mediates gut microbiome Lactobacillus enrichment and airway immune defense against allergens and virus infection. Proceedings of the National Academy of Sciences DOI: /pmas (2013).

21 Early Exposure of Bacteria Birth cohort enrolled since 2005 with 560 children enrolled from four cities Baltimore, Boston, New York, and St. Louis All children have parental history of asthma Examined exposure to cat, dog, roaches, dust mites, & mice Findings: cats, mice, and roach exposure in early life decreased risk of wheezing later in life Substudies: compare 104 children who (a) no asthma or allergies; (b) wheezing only; (c) allergies only; (d) both wheezing and allergies Findings: those exposed to dust with bacteria in it were most likely to be in the no asthma or allergies group High bacterial diversity and early exposure to bacteria are both protective against allergies and asthma SV Lynch et al. Effects of early life exposure to allergens and bacteria on recurrent wheeze and stopy in urban children. Journal of Allergy and Clinical Immunology.

22 Questions? References List National Heart Lung and Blood Institute, National Institutes of Health National Health Interview Survey, National Center for Health Statistics, Centers for Disease Control and Prevention National Center for Health Statistics M Gomez, et al. Adolescent smokers are at greater risk for current asthma and rhinitis. Int J Tuberc Lung Dis. 13 (8): , A Glaser. Asthma, Children and Pesticides. National Coalition Against the Misuse of Pesticides. Vol 25, No 2, MT Salem, et al. Early life environmental risk factors for asthma: findings from the children s healthy study. Environ Health Perspect 2003; 112: JD Thrasher, et al. Immunologic abnormalities in humans exposed to chlorpyrifos: preliminary observations. Arch Environ Med 1993; 48: M Gascon et al. Persistent organic pollutants and children s respiratory health: The role of cytokines and inflammatory biomarkers. Environment International. 2014; 69: W. Karmaus, et al. Infections an datopic disorders in childhood and organochlorine exposure. Arch Environ Health 2001; 56: E Hernandez et al. Prenatal determinants of cord blood total immunoglobulin E levels in Mexican newborns. KE Fujimura et al. House dust exposure mediates gut microbiome Lactobacillus enrichment and airway immune defense against allergens and virus infection. Proceedings of the National Academy of Sciences DOI: /pmas (2013). SV Lynch et al. Effects of early life exposure to allergens and bacteria on recurrent wheeze and stopy in urban children. Journal of Allergy and Clinical Immunology.