Stroke and Subarachnoid Haemorrhage

For฀subarachnoid฀haemorrhage฀SAH,฀one฀study฀has฀examined฀432฀incident฀cases฀of฀ SAH฀frequency฀matched฀to฀473฀community฀SAH-free฀controls฀to฀determine฀dose-฀dependent฀ associations฀of฀active฀and฀passive฀smoking฀at฀home฀and฀smoking฀cessation฀with฀SAH฀ [130] .฀Compared฀with฀never-smokers฀not฀exposed฀to฀passive฀smoking,฀the฀aOR฀for฀SAH฀ among฀current฀smokers฀was฀5.0฀95฀CI,฀3.1–8.1;฀for฀past฀smokers,฀1.2฀95฀CI,฀0.8–2.0;฀ and฀for฀passive฀smokers,฀0.9฀95฀CI,฀0.6–1.5.฀Current฀and฀lifetime฀exposures฀showed฀a฀ clear฀dose-dependent฀effect,฀and฀risks฀appeared฀more฀prominent฀in฀women฀and฀for฀aneu- rysmal฀SAH.฀Approximately฀1฀in฀3฀cases฀of฀SAH฀could฀be฀attributed฀to฀current฀smoking,฀ but฀risks฀decline฀quickly฀after฀smoking฀cessation,฀even฀among฀heavy฀smokers.฀From฀this฀ study,฀it฀was฀concluded฀that฀there฀is฀a฀strong฀positive฀association฀present฀between฀cigarette฀ smoking฀and฀SAH,฀especially฀for฀aneurysmal฀SAH฀and฀women,฀which฀is฀virtually฀elimi- nated฀within฀a฀few฀years฀of฀smoking฀cessation.฀Large฀opportunities฀exist฀for฀preventing฀ SAH฀through฀smoking฀avoidance฀and฀cessation฀programs฀ [130] .

9.5 Respiratory Tract

ETS฀clearly฀impairs฀lung฀function฀variables.฀Forced฀expiratory฀volume฀in฀the฀irst฀second฀ FEV 1 ฀ and฀ forced฀ vital฀ capacity฀ FVC฀ were฀ studied฀ in฀ ETS-exposed฀ workers฀ Scottish฀ MONICA฀Survey:฀FEV 1 ฀fell฀by฀254฀84–420฀ml฀and฀FVC฀by฀273฀60–480฀ml฀compared฀ with฀values฀in฀workers฀not฀exposed฀to฀ETS.฀An฀inverse฀correlation฀between฀cotinine฀levels฀and฀ FVC฀was฀found฀only฀in฀those฀workers฀who฀had฀had฀blood฀collected฀in฀the฀morning฀ [131] . When฀male฀and฀female฀non-smokers฀were฀exposed฀for฀7.33฀hday฀to฀fresh฀diluted฀side- stream฀smoke฀with฀a฀respirable฀suspended฀particle฀concentration฀of฀179฀µgm 3 ,฀signiicant฀ reductions฀in฀FVC฀and฀FEV 1 ฀1.6,฀p฀฀0.05฀and฀in฀PEF฀1.3,฀p฀฀0.03฀were฀detected฀ within฀5฀days฀ [132] .฀The฀observed฀decline฀in฀pulmonary฀function฀was฀accompanied฀by฀ a฀ noradrenaline-induced฀ alteration฀ in฀ blood฀ low,฀ leading฀ to฀ transient฀ bronchocon- striction฀ [132] .

9.5.1 Respiratory Tract in Children and Teenagers

Studies฀and฀meta-analyses฀have฀focused฀in฀particular฀on฀the฀effects฀of฀ETS฀exposure฀on฀the฀ respiratory฀tract฀in฀children฀ [78,฀133–137] .฀ETS฀exposure,฀airway฀symptoms฀and฀respira- tory฀history฀were฀assessed฀in฀an฀urban฀population฀of฀8,008฀randomly฀selected฀inhabitants฀ [137] .฀ In฀ never-smokers฀ with฀ childhood฀ ETS฀ exposure,฀ the฀ prevalence฀ of฀ physician-฀ diagnosed฀asthma฀was฀7.6฀compared฀with฀5.9฀in฀non-exposed฀subjects฀฀p฀=฀0.036,฀and฀ ETS฀was฀reported฀to฀be฀the฀most฀common฀lower฀airway฀irritant฀ahead฀of฀exercise฀in฀cold฀ air,฀dust,฀perfume,฀pollen฀and฀pets฀ [137] . A฀study฀by฀Manning฀et฀al.฀examined฀the฀prevalence฀of฀bronchitis฀cough฀with฀phlegm฀ symptoms฀in฀teenagers฀who฀either฀smoked฀cigarettes฀on฀a฀regular฀basis฀active฀smokers฀or฀ were฀non-smokers฀but฀who฀are฀exposed฀to฀passive฀smoking฀passive฀smokers฀in฀the฀home฀ [138] .฀The฀study฀was฀undertaken฀in฀1995฀and฀repeated฀in฀1998.฀The฀1995฀study฀was฀a฀ cross-sectional฀questionnaire฀survey฀of฀smoking฀habits฀in฀secondary฀school฀children฀aged฀ 13–14฀years฀and฀was฀undertaken฀as฀part฀of฀the฀ISAAC฀questionnaire฀survey.฀Thirty฀repre- sentative฀and฀randomly฀selected฀schools฀from฀throughout฀the฀Republic฀of฀Ireland฀took฀part฀ in฀the฀study.฀In฀the฀1995฀study,฀3,066฀students฀completed฀a฀questionnaire฀on฀their฀current฀ smoking฀habits฀and฀symptoms฀of฀cough฀and฀phlegm.฀The฀authors฀found฀that฀634฀20.7฀ of฀these฀young฀teenagers฀actively฀smoked฀cigarettes฀with฀signiicantly฀more฀females฀smok- ing฀than฀males฀with฀23.3฀of฀girls฀compared฀to฀17.6฀boys฀฀p฀=฀0.0001.฀Percentage฀of฀ non-smoking฀children฀exposed฀to฀smoking฀in฀the฀home฀passive฀smokers฀with฀parental฀ smoking฀accounting฀for฀most฀of฀the฀passive฀smoking฀is฀46.3.฀Bronchitis฀symptoms฀were฀ more฀commonly฀reported฀in฀active฀smokers฀compared฀to฀non-smokers฀with฀an฀OR฀of฀3.02฀ 95฀CI,฀2.34–3.88฀฀p฀฀0.0001฀or฀in฀passive฀smokers฀compared฀to฀those฀not฀exposed฀to฀ smoking฀with฀OR฀of฀1.82฀95฀CI,฀1.32–2.52฀฀p฀฀0.0001.฀The฀1998฀study฀showed฀simi- lar฀results฀for฀smoking฀habits,฀passive฀smoking฀and฀prevalence฀of฀bronchitis฀symptoms฀as฀ with฀the฀1995฀study.฀In฀conclusion,฀the฀results฀of฀this฀study฀documented฀that฀increased฀ bronchitis฀symptoms฀occur฀in฀teenagers฀exposed฀to฀active฀or฀passive฀smoking฀ [138] . A฀study฀by฀Kabesch฀et฀al.฀was฀performed฀to฀determine฀whether฀the฀consequences฀of฀ parental฀smoking฀could฀be฀traced฀in฀adulthood฀ [139] .฀Information฀from฀interviewer-led฀ questionnaires฀was฀available฀for฀18,922฀subjects฀aged฀20–44฀years฀from฀random฀popula- tion฀ samples฀ in฀ 37฀ areas฀ participating฀ in฀ the฀ European฀ Community฀ Respiratory฀ Health฀ Survey.฀Lung฀function฀data฀were฀available฀for฀15,901฀subjects.฀It฀was฀found฀that฀in฀men,฀ father’s฀smoking฀in฀childhood฀was฀associated฀with฀more฀respiratory฀symptoms฀ORwheeze฀ 1.13฀95฀CI,฀1.00–1.28;฀never-smokers:฀ORwheeze฀1.21฀95฀CI,฀0.96–1.50฀and฀there฀ was฀a฀dose-dependent฀association฀between฀number฀of฀parents฀smoking฀and฀wheeze฀one:฀ OR฀ 1.08฀ 95฀ CI,฀ 0.94–1.24;฀ both:฀ OR฀ 1.24฀ 95฀ CI,฀ 1.05–1.47;฀ ptrend฀ =฀ 0.010.฀ A฀reduced฀ratio฀of฀forced฀expiratory฀volume฀in฀FEV 1 ฀to฀FVC฀was฀related฀to฀father’s฀smok- ing฀−0.3฀95฀CI,฀−0.6฀to฀0฀and฀number฀of฀parents฀smoking฀ptrend฀0.001฀among฀ men.฀In฀women,฀mother’s฀smoking฀was฀associated฀with฀more฀respiratory฀symptoms฀and฀ poorer฀lung฀function฀ORwheeze฀1.15฀95฀CI,฀1.01–1.31,฀never-smokers:฀ORwheeze฀ 1.21฀95฀CI,฀0.98–1.51;฀FEV1฀−24฀ml฀95฀CI,฀−45฀to฀−3;฀FEV1FVC฀ratio฀−0.6฀ 95฀CI,฀−0.9฀to฀−0.3.฀These฀effects฀were฀possibly฀accounted฀for฀by฀maternal฀smoking฀ in฀pregnancy฀ORwheeze฀1.39฀95฀CI,฀1.17–1.65;฀FEV1฀−23฀ml฀95฀CI,฀−52฀to฀7;฀ FEV1FVC฀ratio฀−0.9฀95฀CI,฀−1.3฀to฀−0.4฀as฀there฀was฀no฀association฀with฀paternal฀ smoking฀among฀women฀interaction฀by฀sex,฀p฀฀0.05.฀These฀results฀were฀homogeneous฀ across฀centres.฀The฀authors฀concluded฀that฀both฀intrauterine฀and฀environmental฀exposure฀ to฀parental฀tobacco฀smoking฀was฀related฀to฀more฀respiratory฀symptoms฀and฀poorer฀lung฀ function฀in฀adulthood฀in฀this฀multicultural฀study.฀The฀age฀window฀of฀particular฀vulnerabil- ity฀appeared฀to฀differ฀by฀sex,฀postnatal฀exposure฀being฀important฀only฀in฀men฀and฀a฀role฀for฀ prenatal฀exposure฀being฀more฀evident฀in฀women฀ [139] .฀Only฀one฀study฀focussed฀on฀the฀ effects฀ of฀ domestic฀ passive฀ smoking฀ by฀ narghile฀ water฀ pipe฀ andor฀ cigarettes฀ on฀ the฀ development฀of฀respiratory฀ailments฀among฀children฀aged฀10–15฀years฀ [140] .฀In฀this฀study,฀ students฀ were฀ recruited฀ from฀ ive฀ private฀ schools฀ in฀ Beirut,฀ and฀ information฀ on฀ demo- graphic,฀ in-home฀ smoking,฀ and฀ students’฀ respiratory฀ tract฀ illnesses฀ cough,฀ wheezing,฀ runny฀nose,฀or฀nasal฀congestion฀were฀collected฀from฀each฀participant฀results:฀of฀625฀stu- dents฀surveyed,฀438฀70.1฀had฀at฀least฀one฀individual฀smoking฀at฀home.฀Compared฀with฀ the฀ non-exposed฀ group,฀ the฀ OR฀ of฀ having฀ respiratory฀ illness฀ for฀ children฀ exposed฀