Nicotine Dependence and Psychiatric Disorders in the United States:  Results From the National Epidemiologic Survey on Alcohol and RelatedConditions FREE

Smoking is the leading cause of preventable death in the United Statesand the single most important avoidable cause of morbidity and premature mortalityworldwide.^1- 2 Studies have foundhigh smoking rates among mixed samples of psychiatric outpatients and inpatientsand especially high rates among patients with specific psychiatric diagnoses.^3- 6 A recentnational survey also found elevated smoking rates among adults with psychiatricdisorders compared with those without such disorders.⁷ However,these studies did not address the issue of nicotine dependence. Dependenceon psychoactive substances indicates a condition in which repeated self-administrationresults in compulsive substance-taking behavior that is very often chronicand continues despite serious consequences.⁸ Thus,determining the prevalence and comorbidity of nicotine dependence in the generalpopulation and the contribution of these conditions to the total public healthburden caused by cigarette smoking is of the highest public health importance.

Surprisingly, little is known about co-occurrence of nicotine dependenceand psychiatric disorders in representative samples of the adult general populationand how these disorders impact the total smoking public health burden. Themost extensive data are available for regional samples, predominantly amongyoung adults and adolescents. These have included studies in a health maintenanceorganization or among urban samples in Michigan,^3,9- 10 femaletwins in Virginia,¹¹ and young adult and adultsamples in urban regions of Germany.¹² In thesestudies, nicotine dependence was found to be highly associated with a varietyof psychiatric disorders, including substance use disorders and mood and anxietydisorders. In the German National Health Interview and Examination Survey,¹³ the only national survey of adults to examine psychiatriccomorbidity with nicotine dependence, more than 50% of the respondents withdependence fulfilled criteria for at least 1 psychiatric disorder.

To date, no nationally representative survey of the United States hasaddressed the co-occurrence of nicotine dependence and a broad array of psychiatricdisorders among adults, and no community survey has specifically examinedthe association between nicotine dependence and personality disorders (PDs).The absence of accurate national data on the comorbidity of nicotine dependenceand a broad range of psychiatric disorders reflects a gap in our understandingof treatment needs and type of interventions.

To address this gap in our public health knowledge, we present the firstnationally representative data on the prevalence and co-occurrence of DSM-IV⁸ nicotine dependenceand DSM-IV alcohol and drug use disorders, mood andanxiety disorders, and PDs. These disorders were assessed in the NationalInstitute on Alcohol Abuse and Alcoholism’s (NIAAA) 2001-2002 NationalEpidemiologic Survey on Alcohol and Related Conditions (NESARC).^14- 15 Becauseof the NESARC sample size (N = 43 093), accurate estimationwas possible for current or recent (past year) prevalence and co-occurrenceof DSM-IV nicotine dependence and DSM-IV Axis I disorders (alcohol and drug use disorders, major depression,dysthymia, mania, hypomania, panic disorder with and without agoraphobia,social phobia, specific phobia, and generalized anxiety disorder) and AxisII disorders (avoidant, dependent, obsessive-compulsive, histrionic, paranoid,schizoid, and antisocial PDs). Most previous studies were based on DSM-III-R¹⁶ diagnostic criteria thatdiffer significantly from DSM-IV criteria for a numberof disorders, especially nicotine dependence and other drug dependence diagnoses.Prior research also used lifetime measures of nicotine dependence and otherpsychiatric disorders that are less relevant to the public health implicationsof any associations found, less germane to clinicians and practitioners, andsubject to retrospective recall bias. Further, the sample size allowed forthe first time the co-occurrence of these disorders to be examined separatelyby specific psychiatric disorders and sex.

As is well known, the vast majority of nicotine consumption in the UnitedStates is in the form of cigarettes, and thus the public health burden ofnicotine occurs almost entirely through cigarette smoking. To gain an understandingof the contribution of nicotine dependence and psychiatric disorders to thispublic health burden, we also determined the percentage of all cigarettesin the United States that were consumed by individuals with nicotine dependenceand psychiatric disorders. This analysis was stimulated, in part, by tobaccoindustry documents recently released as the result of the 1998 master settlementagreement between state attorneys general and major US tobacco manufacturers.Information in these documents suggests that the tobacco industry designedproducts to target consumer segments with different psychological need profiles,for example, individuals scoring high on neuroticism and anxiety scales whomay have used tobacco to manage mood, anxiety, stress, anger, social dependence,insecurity, and other emotional states.¹⁷ Thecreation of new tobacco brands and their marketing strategies may have resultedin a higher risk of dependence among certain groups who, by virtue of theirpsychopathology, may have been most influenced by them. The present studyprovides an opportunity to address this critical question.

The 2001-2002 NESARC is a representative sample of the United Statesconducted by the NIAAA that has been described in detail elsewhere.^14- 15 The target population of the NESARCwas the civilian, noninstitutionalized population aged 18 years and older,residing in the continental United States, Alaska, and Hawaii. The samplealso included a group-quarters sampling frame (boarding houses, rooming houses,military living off base, nontransient hotels and motels, shelters, facilitiesfor housing workers, college quarters, and group homes). Face-to-face computerizedpersonal interviews were conducted with 43 093 respondents. The overallsurvey response rate was 81%. African American, Hispanic, and young adultindividuals (18-24 years of age) were oversampled in the NESARC. The datawere weighted to reflect the design characteristics of the NESARC, to accountfor oversampling, and to adjust for nonresponse at the household and personlevels. The weighted data were then adjusted to be representative of the UScivilian population for a variety of socioeconomic variables, including urbanicity,region, age, sex, race, and ethnicity, using the 2000 Decennial Census.

Approximately 1800 lay interviewers from the US Bureau of the Censusadministered the NESARC using laptop computer–assisted software thatincluded built-in skip, logic, and consistency checks. On average, the interviewershad 5 years’ experience working on census and other health-related nationalsurveys. The interviewers completed 10 days of training. This was standardizedthrough centralized training sessions under the direction of NIAAA and censusheadquarters staff.

The diagnostic interview used to generate diagnoses presented in thisreport is the NIAAA Alcohol Use Disorder and Associated Disabilities InterviewSchedule–DSM-IV Version (AUDADIS-IV),¹⁸ a state-of-the-art structured diagnostic interviewdesigned for use by lay interviewers.

The AUDADIS-IV included an extensive list of symptom questions thatseparately assessed DSM-IV criteria for nicotinedependence and alcohol and drug-specific abuse and dependence for 10 classesof drugs. These included sedatives, tranquilizers, opiates (other than heroinor methadone), stimulants, hallucinogens, cannabis, cocaine (including crackcocaine), inhalants/solvents, heroin, and other drugs. Consistent with the DSM-IV, 12-month AUDADIS-IV diagnoses of alcohol and otherdrug abuse required a respondent to meet at least 1 of the 4 criteria definedfor abuse in the 12-month period preceding the interview. Nicotine-, alcohol-,and drug-dependence diagnoses, as defined by AUDADIS-IV, required respondentsto satisfy at least 3 of the 7 DSM-IV criteria fordependence during the last year. The withdrawal criterion of each dependencediagnosis was measured as a syndrome, requiring the requisite number of drug-specificwithdrawal symptoms as defined in the DSM-IV withdrawalcategories.

Rather than assessing nicotine dependence in the same modules as alcoholor drugs, we assessed nicotine dependence in a separate AUDADIS-IV module.This was done to closely adhere to the DSM-IV guidelines^8(p243) indicating that generic drug dependencecriteria do not apply or need to be modified to assess nicotine dependence.For example, the “using nicotine to relieve or avoid withdrawal symptoms”criterion was operationalized using the following 4 symptom items: (1) theuse of nicotine upon waking, (2) the use of nicotine after being in a situationin which use was restricted, (3) the use of nicotine to avoid nicotine withdrawalsymptoms, and (4) waking up in the middle of the night to use tobacco. The“giving up activities in favor of nicotine use” criterion wasassessed as (1) giving up or cutting down on activities that were important,like associating with friends or relatives or attending social activities,because tobacco use was not permitted at the activity and (2) giving up orcutting down on activities that you were interested in or gave you pleasurebecause tobacco use was not permitted at the activity. The “great dealof time spent using tobacco” criterion was assessed by the single symptomitem chain-smoking. The “using tobacco more than intended” criterionwas operationalized as having a period when tobacco was used more than intended.Nicotine dependence was assessed for any tobacco product, including cigarettes,cigars, pipes, chewing tobacco, and snuff.

The reliability of nicotine dependence was assessed in a test-reteststudy conducted as part of the NESARC survey proper¹⁹ usingprocedures similar to those used in the German National Health Interview andExamination Survey.¹³ A random subsample of347 respondents was reinterviewed with the AUDADIS-IV nicotine dependencemodule within 10 weeks of their NESARC interview. The reliability of current12-month nicotine dependence was good (κ = 0.63).The validity of nicotine dependence was assessed in a series of linear regressionanalyses, using the NESARC data, that examined the associations between nicotinedependence and Short-Form-12v2 physical disability scores, controlling forage, PDs, current comorbid alcohol and drug use, and mood and anxiety disorders.The Short-Form-12v2, a reliable and valid measure of generic quality of lifeused in large population surveys,²⁰ yields10 component and profile scores assessing various dimensions of physical andmental disability and impairment. In the present analyses, the focus was on6 physical disability scores of the Short-Form-12v2 measuring (1) limitationsin physical functioning due to physical problems, (2) role impairment dueto physical problems, (3) general physical health, (4) bodily pain, (5) vitality,and (6) overall physical disability. Nicotine dependence was shown to be ahighly significant (P<.001) predictor of all 6of these disability scores. Respondents with nicotine dependence had significantlygreater physical disability and dysfunction than respondents who did not havenicotine dependence.

The reliability^{15,19,21- 25} andvalidity^26- 39 ofAUDADIS-IV alcohol and drug use disorders are well documented in clinicaland especially general population samples. The psychometric properties ofAUDADIS-IV alcohol and drug use disorders also were documented in the WorldHealth Organization/National Institutes of Health International Study on Reliabilityand Validity.^40- 44

The DSM-IV mood and anxiety diagnoses reportedhere included major depression, dysthymia, mania, hypomania, panic disorderwith and without agoraphobia, social phobia, specific phobia (simple phobia),and generalized anxiety disorder.

The current (last 12 months) mood and anxiety diagnoses presented inthis article are defined in the DSM-IV as “primary”or independent diagnoses. In the DSM-IV, the termprimary is used as a shorthand to indicate those mental disorders that arenot substance induced and that are not due to a general medical condition.^8(p192) Diagnoses of major depression alsoruled out bereavement.

The reliability of AUDADIS-IV measures of DSM-IV moodand anxiety disorders are documented in test-retest studies among generalpopulation samples.^19,21- 22 Inthese test-retest studies, the reliabilities associated with mood and anxietydisorders were fair to good, ranging from κ = 0.42for specific phobia to κ = 0.64 formajor depression. The validity of mood and anxiety disorders was assessedusing the same procedures as those used for nicotine dependence. Each moodand anxiety disorder was shown to be a highly significant (P<.05 to P<.001) predictor of the 4mental disability scores of the Short-Form-12v2, controlling for age, PDs,and current substance use, mood, and anxiety disorders. Respondents with eachmood or anxiety disorder had significantly greater mental disability and social/occupationaldysfunction than respondents who did not have the specific mood or anxietydisorder.

Diagnoses of PDs require an evaluation of the individual’s long-termpatterns of functioning.^8(p630) Diagnosesof PDs using the AUDADIS-IV were made accordingly. Respondents were askeda series of personality symptom questions about how they felt or acted mostof the time throughout their lives regardless of the situation or whom theywere with. They were instructed not to include times when they were depressed,manic, anxious, drinking heavily, using medicines or drugs, or experiencingwithdrawal symptoms (defined earlier in the AUDADIS-IV) or times when theywere physically ill. To receive a DSM-IV diagnosis,respondents needed to endorse the requisite number of DSM-IV symptom items for the particular PD, and at least 1 positive symptomitem must have caused social and/or occupational dysfunction.

The reliability of AUDADIS-IV categorical diagnoses of each PD alsowas assessed in a test-retest study conducted as part of the NESARC.¹⁹ A random subsample of 282 respondents was reinterviewedwith the antisocial PD module, and another subsample of 315 respondents wasreinterviewed with the AUDADIS-IV modules containing the remaining PD measures.The reliability of the PD diagnoses in these community samples ranged fromfair to good, from κ = 0.40 for histrionicPD to κ = 0.67 for antisocial PD.Reliabilities of the AUDADIS-IV diagnoses compare favorably with those foundfor semistructured personality interviews conducted in treated samples ofpatients.⁴⁵

The validity of PDs was assessed using the same procedures as thoseused for mood and anxiety disorders.¹⁵ Withthe exception of histrionic PD, all PDs were shown to be highly significant(P<.01 to P<.001)predictors of the 4 Short-Form-12v2 mental disability scores. Respondentswith these PDs had significantly greater mental disability and social/occupationaldysfunction than respondents who did not have the PD.

Among those in the survey who were lifetime smokers of cigarettes (definedas smoking at least 100 cigarettes over the life course), current cigaretteuse was defined as any smoking during the year preceding the interview. Amongcurrent smokers, the total number of cigarettes smoked in the last year wasdetermined by respondents’ answers to the following 2 questions: “Onthe days that you smoked in the past year, about how many cigarettes did youusually smoke?” and “About how often did you usually smoke inthe past year?” (eg, daily, 5 to 6 days per week). The total numberof cigarettes smoked in the past year was the product of the respondent’sreplies to these 2 questions.

Similar to the high reliabilities found for other AUDADIS-IV nicotinemeasures, the test-retest reliabilities of the number of cigarettes smokedin the past year and the number of days smoked in the past year were excellent,with intraclass coefficients of 0.83 and 0.84.¹⁹

Cross-tabulations were used to calculate prevalences of nicotine dependenceand all other Axis I and II disorders. Odds ratios (OR) derived from logisticregression analyses were used to study associations between nicotine dependenceand other Axis I and II disorders in the total population and among men andwomen. All standard errors and 95% confidence limits were estimated usingSUDAAN,⁴⁶ a software package that uses Taylorseries linearization to adjust for design effects of complex sample surveyslike the NESARC.

We multiplied the total number of cigarettes smoked in the past yearby the weighted number of persons in the following 4 groups to arrive at thepercentage of all cigarettes consumed in the past year (ie, in 2001-2002)in each group: (1) dependent cigarette smokers with a comorbid psychiatricdisorder, (2) dependent cigarette smokers without a comorbid psychiatric disorder,(3) nondependent cigarette smokers with a psychiatric disorder, and (4) nondependentcigarette smokers without a psychiatric disorder.

Among the total sample, 28.4% were current users of any tobacco product,while 24.9% were current cigarette smokers. The prevalence of nicotine dependencewas 12.8% in the total sample (Table 1).These individuals constituted nearly half of all current nicotine users. Bysex, the prevalence of nicotine dependence was 14.1% among men and 11.5% amongwomen. Nicotine dependence associated with cigarette use constituted 93.7%of all nicotine dependence.

The prevalence of any alcohol use disorder (8.5%) was much greater thanany drug use disorder (2.0%), and for both these disorders, the rates forabuse exceeded those for dependence. The 12-month prevalence rates of anymood and anxiety disorder were 9.2% and 11.1%, respectively, in the totalsample. The most prevalent mood and anxiety disorders were major depression(7.1%) and specific phobia (7.1%). The most prevalent PD in the general populationwas obsessive-compulsive PD (7.9%), followed by paranoid (4.4%), antisocial(3.6%), schizoid (3.1%), avoidant (2.4%), histrionic (1.8%), and dependent(0.5%) PDs.

As indicated in the first column of Table2, the prevalence of any alcohol use disorder was 22.8% among respondentswith current nicotine dependence. The rate of any current mood disorder amongrespondents with nicotine dependence was 21.1%, and the rate of any currentanxiety disorder in the same group was 22.0%. The rate of any PD among nicotine-dependentindividuals was 31.7%. The prevalence of any drug use disorder among nicotine-dependentindividuals was lower (8.2%).

When specific Axis I and II disorders were considered, the prevalenceof current alcohol dependence (13.5%) was greater than the prevalence of currentalcohol abuse (9.3%) among nicotine-dependent individuals. The opposite wastrue for any drug use disorder where the prevalence of drug abuse (4.8%) wasgreater than dependence (3.4%). Major depression (16.6%) and specific phobia(14.3%) were by far the most prevalent mood and anxiety disorders among individualswith current nicotine dependence. As for the Axis II PDs, no intraclusterpatterns were observed. Obsessive-compulsive PD (14.4%, cluster C PD), antisocialPD (12.2%, cluster B PD), and paranoid PD (11.7%, cluster A PD) were the mostprevalent among nicotine-dependent individuals.

Nicotine dependence was most prevalent among individuals with a currentalcohol or drug use disorder (34.5% and 52.4%, respectively). The correspondingprevalences of nicotine dependence among individuals with any mood or anxietydisorder or PD were somewhat lower (29.2%, 25.3%, and 27.3%, respectively).

Among individuals with a current substance use disorder, the rate ofnicotine dependence was greater for those with alcohol or drug dependence(45.4% and 69.3%, respectively) than for those with alcohol or drug abuse(25.5% and 44.7%, respectively). There was little variation in the prevalenceof nicotine dependence among individuals with specific mood (30.0%-35.3%),anxiety (25.6%-39.8%), and personality (23.3%-44.0%) disorders.

Associations between current nicotine dependence and current Axis Iand II disorders are shown in the third column of Table2. All OR were substantialin size and significant. Nicotine dependence was most strongly related toany drug use disorder (OR, 8.1) and any alcohol use disorder (OR, 4.4). Therelationship was stronger for alcohol (OR, 6.4) and drug (OR, 15.9) dependencethan for alcohol (OR, 2.5) or drug (OR, 5.7) abuse. There was little variationin the strength of associations between nicotine dependence and specific mood(OR, 3.3-3.9), anxiety (OR, 2.6-4.6), and personality (OR, 2.3-5.7) disorders.Comorbidity rates and associations between current nicotine dependence andcurrent Axis I and II disorders among men and women were strikingly similarto one another and to those observed for the total population (Table 3).

Nicotine-dependent individuals made up only 12.8% of the population,but they consumed 57.5% of all cigarettes smoked in the United States. Individualswith a current psychiatric disorder (with and without nicotine dependence)made up 30.3% of the population, and they consumed 46.3% of all cigarettessmoked in the United States. Although respondents with current nicotine dependenceand at least 1 comorbid psychiatric disorder made up only 7.1% of the totalUS adult population, they consumed 34.2% of all cigarettes smoked in the UnitedStates.

Respondents without comorbidity between nicotine dependence and psychiatricdisorders smoked lower proportions of the total number of cigarettes smoked.Those with a current psychiatric disorder but no nicotine dependence consumed12.1% of all cigarettes smoked. Respondents with nicotine dependence and nopsychiatric disorder consumed 23.3% of all cigarettes smoked. Current smokerswithout nicotine dependence or a psychiatric disorder consumed 30.4% of allcigarettes smoked.

The co-occurrence of DSM-IV current nicotinedependence and PDs and of current substance use, mood, and anxiety disordersand PDs is pervasive in the US population. Among respondents with currentnicotine dependence, between 21.1% and 31.7% had a current alcohol use, mood,or anxiety disorder or PD. The prevalence of any drug use disorder among individualswith nicotine dependence was 8.2%. Current nicotine dependence also was highlyprevalent among individuals with Axis I or II disorders (25.3%-52.4%). Further,associations between current nicotine dependence and current alcohol and druguse disorders, specific mood and anxiety disorders, and PDs all were substantialand statistically significant for the total sample and among men and women.

Nicotine dependence was more strongly related to alcohol and drug usedisorders, especially drug dependence, than any other Axis I or II disorderexamined in this study. These results are consistent with evidence concerningthe reciprocal effects of nicotine and other psychoactive substances throughshared physiological effects, cross-tolerance, or cueing.^47- 50 Withregard to physiological effects, substance abusers may smoke to decrease someof the negative effects of alcohol or other drugs. Synergistic physiologicaleffects may contribute to the concurrent use of nicotine and other substancesbut also may lead to increased use of both kinds of substance and/or the developmentof nicotine and substance dependence because of cross-tolerance. The use ofone of these substances also may cue the use of the other, creating a learnedassociation between the 2 consumption behaviors. Further research is neededto test these different hypotheses.

Previous studies also have found significant associations between nicotinedependence and substance use disorders and mood and anxiety disorders. Theearlier studies, however, were very different in design, with numerous featuresthat limited their generalizability or the information they provided. Forexample, the German National Comorbidity Survey that included nicotine dependencewas too small to examine the relationship of nicotine dependence to specificsubstance use, mood, and anxiety disorders. Studies of adolescents and youngadults are limited by restricted age ranges. Previous studies also were limitedgeographically and by use of lifetime measures of disorders, which providemuch less information on the current public health implications of any associationsfound. Nonetheless, the magnitude of the associations between nicotine dependenceand other Axis I disorders examined among adolescents and young adults^3,9- 10 was similar to thatfound in this study. These similarities suggest that these comorbid patternsbecome established early and persist. This indicates that a large part ofthe prevention effort should be targeted at young individuals.

The NESARC is the first national survey to assess DSM-IV nicotine dependence as well as DSM-IV AxisII PDs. Current nicotine dependence was highly associated with avoidant, dependent,obsessive-compulsive, paranoid, schizoid, histrionic, and antisocial PDs inthe overall sample and among men and women. These results are consistent withearlier research showing associations between smoking (or nicotine dependence)and personality characteristics, primarily neuroticism and extroversion.^8,10 In these studies, neuroticism wasfound to account in part for the associations between smoking and nicotinedependence and major depression by acting as a common genetic and/or environmentalpredisposition to both disorders. That a broad array of PDs might contributeto the associations between nicotine dependence and other Axis I disordersis intriguing and the subject of separate ongoing analyses.

We showed that a very high percentage of cigarettes smoked in the UnitedStates were consumed by those with nicotine dependence and/or psychiatricdisorders relative to their representation in the population as a whole. Forexample, nicotine-dependent individuals made up 12.8% of the population, butthey consumed 57.5% of all cigarettes smoked in the United States. Nicotine-dependentindividuals with a comorbid psychiatric disorder made up 7.1% of the populationyet consumed 34.2% of all cigarettes smoked in the United States. These strikingresults are consistent with those of Lasser et al,⁷ whofound a high rate of smoking among individuals with a psychiatric disorderin the early 1990s. A recent analysis by Le Cook et al¹⁷ of239 relevant industry documents dated 1960 to 1996 suggests that the industrydesigned products to target consumer segments with various psychological needs.Psychological needs in these studies, measured in some by standard, well-validatedpsychiatric assessment instruments (eg, Eysenck Neuroticism Scale⁵¹ and Taylor-Spence Manifest Anxiety Scale⁵²), included neuroticism, anxiety, obsessive behavior,social dependence, nervousness, irritation, and smoking to manage mood, anxiety,anger, worry, unhappiness, social insecurity, and family and other stresses.These psychological and personality characteristics are, of course, strikinglysimilar to the DSM-IV Axis I and II disorder symptomatologymeasured in our study. Further, these analyses suggest that the industry notonly sought to incorporate knowledge of personality characteristics in thedesign of existing and new brands but also conducted research to relate thesepsychological and personality characteristics to corresponding smoking behaviors.For example, one industry study⁵³ cited byLe Cook concluded that these psychological and personality constructs werepositively associated with cigarette consumption, depth of inhalation, andanticipated difficulty in giving up smoking.

Our study is the first to demonstrate that nicotine dependence is highlyassociated with DSM-IV Axis I and II disorders ina representative sample of the US general population. This study also is thefirst to show that individuals with nicotine dependence, psychiatric disorders,and comorbid nicotine dependence and psychiatric disorders carry a very largeshare of the burden of all US tobacco consumption. These results clearly indicatethe importance of focusing smoking prevention and cessation efforts on thesevulnerable subgroups of the population who may have been more likely to beinfluenced by tobacco advertising. Further, in the past, smoking preventionand cessation research has focused on individual differences in psychologicalresponse, need, and addiction to tobacco use to identify prevention and interventiontargets. The present study suggests that research on macro-level approachesis also needed, addressing the best methods to counter consumer segmentationand other marketing strategies. Such information may increase our understandingof the factors that undermine the effectiveness of existing coping and cessationstrategies.

The results of this study are consistent with the conclusions of LeCook et al¹⁷ that awareness of tobacco productdevelopment and marketing can improve smoking cessation efforts by cliniciansand other health care professionals among all smokers and especially amongthe most vulnerable. This knowledge also can be used in broader public policyinterventions, such as media campaigns, to target antitobacco advertisementstoward psychiatrically vulnerable subgroups of the population. Moreover, thesheer magnitude of the comorbidity found between DSM-IV nicotine dependence and Axis I and II disorders suggests that knowledgeof the psychological and personality constructs underlying product developmentwill be helpful in researching causes of nicotine dependence and its psychiatriccomorbidity.

Submitted for Publication: March 29, 2004;final revision received June 9, 2004; accepted June 15, 2004.

Correspondence: Bridget F. Grant, PhD, PhD,Laboratory of Epidemiology and Biometry, Room 3077, Division of IntramuralClinical and Biological Research, National Institute on Alcohol Abuse andAlcoholism, National Institutes of Health, MS 9304, 5635 Fishers Lane, Bethesda,MD 20892-9304 (bgrant@willco.niaaa.nih.gov).

Disclaimer: The views and opinions expressedin this report are those of the authors and should not be construed as representingthe views of any of the sponsoring organizations, agencies, or the US government.