Early Rather than Recent Exposure to Tobacco Increases Bronchial Reactivity

Abstract

Background: Tobacco is well known to impair respiratory function of infants and children. This study was done to identify periods of increased vulnerability of the airways to tobacco products. Patients and methods: In 162 unselected schoolchildren maximum expiratory flow at 25 % of vital capacity (MEF25) was measured before and after cold air hyperventilation. Parental smoking habits were assessed by measurement of cotinine concentrations in children's urine and by interview. Results: Children, whose mothers had smoked during pregnancy, showed increased bronchial reactivity at school age compared to children whose mothers had not smoked during pregnancy (median MEF25 [25th, 75th percentile] after cold air challenge as percent of baseline: 83 % [76, 95] vs. 95 % [79, 100]; p = 0.03). Similar differences were found, when the study population was divided according to the maternal smoking status during the first six months of life. On the contrary, if the cotinine excretion exceeded the group median as a measure of recent exposure to tobacco smoke, bronchial reactivity was not increased (median MEF25 [25th, 75th percentile] as percent of baseline: 88 % [76, 100] vs. 93 % [79, 100]; p = 0.25). Conclusions: Pregnancy and early infancy were found to be periods of increased vulnerability of the airways to tobacco products.

Zusammenfassung

Hintergrund: Es bestehen keine Zweifel daran, dass Tabakrauch die Atemwege von Kindern schädigt. Ziel dieser Studie war es, Phasen mit erhöhter Empfindlichkeit der Atemwege gegenüber Tabakprodukten zu identifizieren. Patienten und Methode: Bei 162 unselektierten Schulkindern wurde der maximale expiratorische Fluss bei 25 % der Vitalkapazität (MEF25) vor und nach einer Kaltluftprovokation gemessen. Die elterlichen Rauchgewohnheiten wurden erfasst durch die Messung der Cotinin-Konzentration im Urin der Kinder und durch Befragung. Ergebnisse: Kinder, deren Mütter in der Schwangerschaft geraucht hatten, zeigten eine höhere bronchiale Reaktivität im Schulalter als Kinder, deren Mütter in der Schwangerschaft nicht geraucht hatten (Median des MEF25 [25. und 75. Perzentile] nach Kaltluftprovokation in Prozent des Ausgangswertes: 83 % [76, 95] vs. 95 % [79, 100]; p = 0,03). Ähnliche Unterschiede fanden sich, wenn die Studienpopulation gemäß dem mütterlichen Rauchstatus in den ersten 6 Lebensmonaten des Kindes aufgeteilt wurde. Im Gegensatz dazu war die bronchiale Reaktivität nicht erhöht, wenn die Cotinin-Ausscheidung den Gruppenmedian überschritt als Hinweis für kürzer zurückliegende Tabakexposition (Median des MEF25 [25. und 75. Perzentile] in Prozent des Ausgangswertes: 88 % [76, 100] vs. 93 % [79, 100]; p = 0,25). Schlussfolgerung: Die Schwangerschaft und die ersten 6 Lebensmonate erwiesen sich als Zeitraum mit erhöhter Verletzlichkeit der Atemwege gegenüber Tabakprodukten.

Key words

Environmental tobacco smoke - cold air challenge - bronchial reactivity

Schlüsselwörter

Passivrauchen - Kaltluftprovokation - Bronchiale Reaktivität

Literatur

• 1 Strachan D P, Cook D G. Health effects of passive smoking. 1. Parental smoking and lower respiratory illness in infancy and early childhood.  Thorax. 1997;  52 905-914
• 2 Gortmaker S L, Walker D K, Jacobs F H, Ruch-Ross H. Parental smoking and the risk of childhood asthma.  Am J Publick Health. 1982;  72 574-579
• 3 Halken S, Host A, Nilsson L, Taudorf E. Passive smoking as a risk factor for development of obstructive respiratory disease and allergic sensitization.  Allergy. 1995;  50 97-105
• 4 DiFranza J R, Lew R A. Morbidity and mortality in children associated with the use ofa tobacco products by other people.  Pediatrics. 1996;  97 560-568
• 5 Cook D G, Strachan D P, Carey I M. Health effects of passive smoking. 9. Parental smoking and spirometric indices in children.  Thorax. 1998;  53 884-893
• 6 Gilliland F D, Berhane K, McConnell R. et al . Maternal smoking during pregnancy, environmental tobacco smoke exposure and childhood lung function.  Thorax. 2000;  55 271-276
• 7 Strachan D P, Jarvis M J, Feyerabend C. The relationship of salivary cotinine to respiratory samptoms, spirometry, and exercise-induced bronchospasm in seven-year-old children.  Am Rev Respir Dis. 1990;  142 147-151
• 8 Martinez F D, Cline M, Burrows B. Increased incidence of asthma in children of smoking mothers.  Pediatrics. 1992;  89 21-26
• 9 Wright A L, Holberg C, Martinez F D, Taussig L M. Relationship of parental smoking to wheezing and nonwheezing lower respiratory tract illnesses in infancy.  J Pediatr. 1991;  118 207-214
• 10 Junge B, Nagel M. Smoking behavior in Germany.  Gesundheitswesen. 1999;  61 121-125
• 11 Zach M, Polgar G, Kump H, Kroisel P. Cold air challenge of airway hyperreactivity in children: practical application and theoretical aspects.  Pediatr Res. 1984;  18 469-478
• 12 Pedersen O F, Miller M R. Lung function. In: Respiratory Epidemiology in Europe. Sheffield; European Respiratory Society 2000: 167-198
• 13 Nicolai T, von Mutius E, Reitmeir P, Wyst M. Reactivity to cold-air hyperventilation in normal and in asthmatic children in a survey of 5697 schoolchildren in southern Bavaria.  Am Rev Respir Dis. 1993;  147 565-572
• 14 Abt K. Descriptive data analysis: a concept between confirmatory and exploratory data analysis.  Methods Inf Med. 1987;  26 77-88
• 15 von Mutius E, Martinez F D, Fritzsch C, Nicolai T, Roell G, Thiemann H H. Prevalence of asthma and atopy in two areas of West and East Germany.  Am J Respir Crit care Med. 1994;  149 358-364
• 16 von Mutius E, Illi S, Hirsch T, Leupold W, Keil U, Weiland S K. Frequency of infections and risk of asthma, atopy and airway hyperresponsiveness in children.  Eur Respir J. 1999;  14 4-11
• 17 Jaakkola M S. Environmental tobacco smoke and respiratory diseases.  In: Respiratory Epidemiology in Europe. Sheffield; European Respiratory Society 2000: 322-383
• 18 Jorres R, Magnussen H. Influence of short-term passive smoking on symptoms, lung mechanics and airway responsiveness in asthmatic submeces and healthy controls.  Eur Respir J. 1992;  5 936-944
• 19 Peat J K, Salome C M, Woolcock A J. Factors associated with bronchial hyperresponsiveness in Australian adults and children.  Eur Respir J. 1992;  5 921-929
• 20 Watts R R, Langone J J, Knight G J, Lewtas J. Cotinine analytical workshop report: consideration of analytical methods for determining cotinine in human body fluids as a measure of passive exposure to tobacco smoke.  Environ Health Perspect. 1990;  84 173-182
• 21 Frischer T, Kuehr J, Meinert R. et al . Maternal smoking in early childhood: a risk factor for bronchial responsiveness to exercise in primary-school children.  J Pediatr. 1992;  121 17-22
• 22 Cunningham J, Dockery D W, Speizer F E. Maternal smoking during pregnancy as a predictor of lung function in children.  Am J Epidemiol. 1994;  139 1139-1152
• 23 Nuesslein T G, Beckers D, Rieger C H. Cotinine in meconium indicates risk for early respiratory tract infections.  Hum Exp Toxicol. 1999;  18 283-290
• 24 Fergusson D M, Horwood L J, Shannon F T. Parental smoking and respiratory illness in infancy.  Arch Dis Child. 1980;  55 358-361
• 25 Henry R L, Hodges I G, Milner A D, Stokes G M. Respiratory problems 2 years after acute bronchiolitis in infancy.  Arch Dis Child. 1983;  58 713-716
• 26 Murray M, Webb M S, O'Callighan C, Swarbrick A S, Milner A D. Respiratory status and allergy after bronchiolitis.  Arch Dis Child. 1992;  67 482-487
• 27 Korppi M, Kuikka L, Reijonen T, Remes K, Juntunen-Backman K, Launiala K. Bronchial asthma and hyperreactivity after early childhood bronchiolitis or pneumonia. An 8-year follow-up study.  Arch Pediatr Adolesc Med. 1994;  148 1079-1084
• 28 Riedel F, Nüßlein T, Rüschoff J, Rieger C HL. Tobacco smoke enhances allergic bronchial sensitization in the guinea pig.  Pediatr Allergy Immunol. 1990;  1 26-33
• 29 Ownby D R, McCullough J. Passive exposure to cigarette smoke does not increase allergic sensitization in children.  J Allergy and Clin Immunol. 1988;  82 634-638
• 30 Henderson F W, Henry M M, Ivins S S. et al . Correlates of recurrent wheezing in school-age childdren. the Physicians of Raleigh Pediatric Associates.  Am J Respir Crit Care med. 1995;  151 1786-1793
• 31 Strachan D P, Cook D G. Health effect sof passive smoking. 5. Parental smoking and allergic sensitization in children.  Thorax. 1998;  53 117-123