Smoker Personality Profiles and Genetic Inheritance of Smoking

Psychosocial฀characteristics฀that฀predispose฀adolescents฀to฀take฀up฀smoking฀were฀inves- tigated฀in฀a฀sixth฀grade฀class฀and฀again฀2฀years฀later฀in฀the฀eighth฀grade฀in฀Canada฀ [69] .฀The฀ signiicant฀ factors฀ were฀ found฀ to฀ include฀ attitudes฀ and฀ behaviour฀ relative฀ to฀ smoking,฀ smoking฀by฀others฀in฀the฀children’s฀environment,฀gender฀and฀stress.฀The฀gender฀difference฀ in฀the฀sixth฀grade฀lay฀in฀the฀fact฀that฀boys฀were฀more฀inluenced฀than฀girls฀by฀people฀smok- ing฀ in฀ their฀ environment.฀ In฀ the฀ eighth฀ grade,฀ on฀ the฀ other฀ hand,฀ boys฀ tended฀ to฀ start฀ ฀smoking฀for฀reasons฀related฀to฀personal฀abilities฀coping฀with฀life,฀self-respect,฀social฀inte- gration,฀acquisition฀of฀skills,฀conformist฀tendencies฀and฀rebellion.฀The฀main฀reasons฀why฀ girls฀took฀up฀smoking฀at฀this฀age฀were฀related฀to฀people฀in฀their฀environment฀who฀smoked฀ and฀rebellion.฀Regular฀smoking฀often฀begins฀as฀experimental฀smoking฀within฀one’s฀peer฀ group,฀especially฀in฀children฀of฀a฀depressive฀or฀anxious฀nature฀ [70] .฀In฀female฀teenagers,฀ regular฀smoking฀correlates฀with฀a฀tendency฀to฀depression฀and฀anxiety฀reactions฀ [71] .฀Other฀ depressive฀symptoms฀that฀predispose฀to฀adolescent฀smoking฀include฀unhappiness,฀despon- dency,฀hopelessness฀about฀the฀future฀and฀dificulty฀in฀falling฀asleep฀ [71] . According฀to฀the฀indings฀from฀twins฀research,฀the฀comorbidity฀of฀organic฀depression฀ and฀nicotine฀dependence฀results฀from฀general฀familial฀factors฀that฀may฀be฀of฀a฀genetic฀ nature฀ [72] .฀A฀genetic฀study฀revealed฀relationships฀between฀neuroses฀and฀smoking฀behav- iour฀ nicotine฀ volume฀ uptake,฀ dependence,฀ motivation฀ to฀ smoke฀ and฀ the฀ polymorphic฀ region฀5-HTT-LPR:฀s฀or฀l฀allele,฀short฀or฀long฀allele,฀ss฀or฀sl฀linked฀to฀the฀5-HT฀trans- porter฀gene.฀A฀predominance฀of฀functional฀polymorphism฀of฀the฀serotonin฀transporter฀gene฀ was฀posited,฀as฀was฀domination฀of฀the฀genotype฀5-HTTLPR-s฀over฀5-HTTLPR-l.฀Apparently,฀ the฀ neurosis฀ and฀ the฀ 5-HTTLPR-s฀ constellation฀ interact฀ in฀ their฀ inluence฀ on฀ nicotine฀ dependence฀ [73,฀74] .฀Another฀study฀involving฀72฀autistic฀subjects฀revealed฀variances฀in฀the฀ distribution฀of฀the฀two฀phenotypes฀ss฀and฀sl฀ [75] .

7.1.5 Depression

7.1.5.1 Smoking Prevalence

The฀prevalence฀of฀smoking฀among฀those฀who฀suffer฀from฀depression฀is฀higher฀than฀in฀the฀ normal฀population฀ [5] ฀but฀lower฀than฀among฀people฀with฀schizophrenia.฀In฀recent฀years,฀there฀ has฀been฀growing฀interest฀in฀the฀thesis฀of฀comorbidity฀of฀depressive฀conditions฀and฀raised฀ciga- rette฀consumption,฀already฀pronounced฀in฀adolescence฀Table฀ 7.2 ฀ [4,฀6,฀72,฀76,฀77] .฀Depressive฀ symptoms฀and฀clinical฀pictures฀with฀depressive฀content฀are฀more฀common฀among฀people฀who฀ Variable฀ Depressive฀illness฀ No฀depressive฀illness฀ OR฀95฀CI Whole฀group 90฀20.0 857฀5.1 4.6฀2.5–8.4 Men 26฀23.1 447฀5.2 5.5฀2.0–15.1 Women 64฀18.9 410฀5.1 4.3฀2.0–9.2 Table 7.2 ฀฀฀Nicotine฀dependence฀among฀1,265฀adolescents฀with฀or฀without฀concurrent฀depression.฀ Frequency฀igures,฀absolute฀and฀percentage฀,฀as฀well฀as฀odds฀ratios฀with฀a฀95฀conidence฀ interval฀ [52] also฀smoke฀OR฀between฀2.1฀and฀5.7฀ [6,฀72,฀78–80] .฀Women฀who฀smoke฀are฀more฀likely฀to฀ have฀a฀history฀of฀depression฀ [81] .฀Among฀depressive฀patients,฀however,฀there฀are฀no฀gender฀ differences฀in฀terms฀of฀smoking฀prevalence฀ [6] .฀Among฀272฀New฀Zealand฀women฀smokers฀ 20฀years฀of฀age,฀63.2฀had฀concurrent฀psychiatric฀disease฀and฀only฀22.7฀were฀psychiatri- cally฀normal.฀A฀study฀involving฀over฀3,200฀patients฀demonstrated฀that฀all฀of฀the฀74฀who฀had฀ experienced฀a฀depressive฀episode฀in฀their฀lives฀had฀also฀been฀smokers,฀whereas฀only฀53฀of฀ the฀psychologically฀healthy฀patients฀had฀smoked฀and฀that฀too฀only฀once฀ [6] .

7.1.5.2 Peculiarities of the Smoker’s Personality

The฀motives฀for฀smoking฀ [82] ,฀expressed฀by฀both฀sexes฀suffering฀from฀a฀depressive฀state฀ more฀frequently฀than฀by฀non-depressives,฀are฀the฀hoped฀for฀stimulation฀correlating฀positively฀ with฀the฀degree฀of฀dependence,฀sedation฀irrespective฀of฀the฀degree฀of฀dependence฀and฀ mastery฀of฀negative฀emotional฀situations.฀Depressive฀patients฀showed฀a฀higher฀rate฀of฀depen- dence฀and,฀in฀connection฀with฀this,฀reduced฀joie฀de฀vivre฀anhedonia.฀An฀increased฀frequency฀ of฀depressive฀episodes฀in฀the฀spring฀occurs฀only฀in฀smokers,฀i.e.฀it฀is฀not฀seen฀in฀non-smokers฀ [83] .฀Smokers฀of฀both฀sexes฀in฀a฀psychiatric฀clinic฀had฀a฀higher฀suicide฀rate฀than฀a฀correspond- ing฀group฀of฀non-smoking฀clinic฀patients.฀A฀previous฀suicide฀attempt฀was฀found฀twice฀as฀ often฀in฀the฀medical฀histories฀of฀smokers฀than฀in฀non-smokers,฀and฀moderate฀to฀severe฀suicide฀ ixations฀were฀expressed฀1.43฀times฀more฀frequently฀among฀the฀smokers฀than฀among฀the฀non- smoking฀group฀ [84] .฀Therefore฀an฀interactive฀relationship฀appears฀to฀exist฀between฀smoking฀ and฀depression:฀smoking฀leads฀to฀a฀higher฀rate฀of฀depression฀and฀depression฀predisposes฀ people฀to฀smoke฀ [85,฀86] .฀These฀interactions฀also฀apply฀to฀adolescents฀ [87] . Both฀those฀predisposed฀to฀depression฀and฀depressive฀smokers฀displayed฀less-effective฀ “cognitive฀coping฀strategies”฀than฀non-smokers฀and฀non-depressives฀in฀terms฀of฀Ways฀of฀ Responding฀WOR฀tests,฀leading฀to฀an฀attempt฀at฀additional฀“cognitive฀behavioural฀ther- apy”฀as฀part฀of฀withdrawal฀therapy฀for฀smokers฀at฀high฀risk฀of฀depression฀ [88] .฀Any฀con- nection฀between฀a฀disposition฀to฀psychiatrically฀relevant฀disturbances฀mood,฀anxiety฀or฀ substance-abuse฀disorders฀and฀therapeutic฀success฀was฀rejected฀on฀the฀basis฀of฀combined฀ withdrawal฀therapy฀with฀luoxetine฀plus฀behavioural฀therapy,฀so฀that฀a฀connection฀between฀ mood฀and฀unsatisfactory฀treatment฀outcome฀was฀only฀detected฀in฀smokers฀without฀any฀ previous฀psychiatric฀disease฀ [89] .

7.1.5.3 Reasons for Increased Cigarette Consumption

In฀view฀of฀the฀fact฀that฀tobacco฀smoke฀contains฀a฀number฀of฀psychoactive฀substances฀in฀ addition฀to฀nicotine,฀it฀is฀conceivable฀that฀these฀substances฀interact฀with฀the฀nicotine฀recep- tor฀to฀increase฀the฀release฀of฀neurotransmitters.฀The฀secretion฀of฀many฀neurotransmitters฀ noradrenaline,฀serotonin,฀dopamine,฀acetylcholine,฀g-amino-butyric฀acid฀and฀glutamate฀is฀ increased฀by฀the฀binding฀of฀nicotine฀to฀central฀nicotine฀receptors.฀Changes฀in฀serotonin฀ 5-HT฀formation฀and฀secretion฀caused฀by฀chronic฀smoking฀are฀also฀under฀฀discussion฀ [90] .