Nicotine dependence among African American light smokers: a comparison of three scales

Approximately 50% of African American (AA) smokers are light smokers (smoke 相似文献   

Smoking, nicotine dependence and psychiatric comorbidity--a population-based study including smoking cessation after three years

BACKGROUND: Evidence suggests that nicotine-dependent smokers are at increased risk for psychiatric comorbidity but general population data that included the number of nicotine dependence and withdrawal symptoms according to DSM-IV, the Fagerstrom Test for Nicotine Dependence (FTND), somatoform disorders and the number of psychiatric diagnoses are rare. The goal of the present study was to analyse relationships of smoking and nicotine dependence with psychiatric disease and whether psychiatric disease predicts the sustaining of smoking after three years. METHODS: Cohort study with a random adult population sample in a northern German region (N = 4075) including a baseline measurement of ever daily smokers aged 18-64 (n = 2458), a first follow-up of the current smokers at baseline (n = 1552) after 30 months and a second follow-up after 36 months. Measures included DSM-IV diagnoses by the Composite International Diagnostic Interview, FTND, smoking cessation by interview. RESULTS: Current daily smokers showed higher odds of a substance use disorder other than nicotine dependence compared with never smokers (odds ratio, OR, 4.6; confidence interval, CI, 2.9-7.2), affective (OR 1.8; CI 1.4-2.5), anxiety (OR 1.6; CI 1.2-2.0) or somatoform disorder (OR 1.4; CI 1.0-1.8). DSM-IV nicotine dependence and the FTND were positively related with the number of psychiatric diagnoses. Psychiatric comorbidity did not predict the maintenance of smoking or quitting. CONCLUSIONS: Findings of increased rates of mental disorders among smokers and nicotine-dependent smokers in the adult general population are supported by this study. The number of nicotine dependence and withdrawal symptoms are related to mental disorders. In addition, somatoform disorders show relationships with smoking similar to relationships with depressive or anxiety disorders. The intention to stop smoking should be proactively supported among these comorbid patients.     

Predictive validity of four nicotine dependence measures in a college sample

BACKGROUND: The present study compared the predictive and incremental validity of four commonly used dependence measures (Diagnostic and Statistical Manual-IV [DSM-IV] nicotine dependence criteria, Fagerstrom Test for Nicotine Dependence [FTND], Hooked On Nicotine Checklist [HONC], Nicotine Dependence Syndrome Scale [NDSS]) in a first year college sample reporting light smoking patterns. METHODS: Nicotine dependence measures were administered at the end of the first semester and follow-up smoking behavior (i.e. continued smoking, quantity, frequency, and length of abstinence) was assessed at the end of the first and second academic years. RESULTS: Higher levels of dependence as measured by the HONC and DSM-IV predicted smoking behavior at both follow-up assessments. While higher scores on some of the NDSS factors predicted heavier smoking behavior during follow-up assessments, higher scores on other NDSS factors predicted lighter smoking behavior. The DSM-IV, NDSS-priority, and HONC measures provided some evidence for incremental validity. Higher dependence scores on all four measures were related to shorter lengths of smoking abstinence. CONCLUSIONS: The four dependence measures were differentially related to smoking behavior outcomes in a light smoking sample. These findings suggest that nicotine dependence can predict a variety of smoking behaviors in light smokers.     

Consistency or change in nicotine dependence according to the Fagerström Test for Nicotine Dependence over three years in a population sample

The goal was to determine whether nicotine dependence levels remain consistent or change over three years. From a population- based sample of 4075 residents aged 18-64, drawn at random, data of 696 individuals was used, who had smoked cigarettes for 21 years on average. Nicotine dependence was assessed by the Fagerstr?m Test for Nicotine Dependence (FTND) at baseline, and 30 and 36 months later. In addition, nicotine dependence and alcohol dependence were diagnosed according to the American Psychiatric Association (DSM-IV). We found an increase in the FTND over 36 months. Subgroups were revealed with sustained high, increasing, decreasing, and sustained low rates of the FTND sum score. Male gender, age at onset of smoking 15 years or younger, DSM-IV nicotine dependence, and DSM-IV alcohol dependence at baseline predicted a sustained high FTND. We conclude that nicotine dependence is increasing even after many years of smoking in an adult population sample.     

Multidimensional assessment of nicotine dependence in adolescents

Despite the critical importance of adolescent smoking, the assessment of nicotine dependence during this developmental period has been the subject of relatively little research. In this study, 301 adolescents (ages 12 through 18 years) reporting daily smoking were recruited for a project on alcohol use disorders (AUDs). The sample included 140 females and 161 males, 251 subjects from clinical and 50 from community sources, and 176 subjects with AUDs at the baseline assessment. Subjects were evaluated with the Nicotine Dependence Syndrome Scale (NDSS), the Fagerstrom Test for Nicotine Dependence (FTND) and a determination of average number of cigarettes per day (cigarettes/day). A varimax factor analysis of 27 NDSS items revealed four factors: (1) Drive/Tolerance (13 items; Cronbach alpha = 0.91); (2) Continuity (five items; Cronbach alpha = 0.67); (3) Priority (three items; Cronbach alpha = 0.64); (4) Stereotypy (five items; Cronbach alpha = 0.66). The NDSS total score, refined by the removal of four items, was also examined (23 items; Cronbach alpha = 0.90). Predicting cigarettes/day at follow-up, initial smoking rate was the best predictor, with the FTND and NDSS Total score showing significant and similar predictive validity. The NDSS Total showed incremental validity in the prediction of smoking progression in a model including demographic characteristics, initial smoking rate and FTND. The findings suggest that the NDSS has acceptable psychometric properties when applied to adolescents, complementing smoking rate and FTND in a multidimensional smoking assessment.     

Validation of the nicotine dependence syndrome scale (NDSS): a criterion-group design contrasting chippers and regular smokers

The nicotine dependence syndrome scale (NDSS) is a new multi-dimensional measure of nicotine dependence, yielding five scores for different aspects of dependence as well as a total score. In this study, we tested the NDSS in a young adult sample (mean age=24), using an extreme-groups comparison between non-dependent smokers (chippers, n=123) and regular smokers (n=130). Scores on each NDSS subscale strongly discriminated between the groups, with the NDSS-total discriminating them almost perfectly. The subscales were generally independent discriminators, demonstrating the discriminant validity of the subscales. NDSS scales also discriminated levels of intake and dependence within the chippers group, suggesting that the scales were sensitive to individual differences even at the very low end of the dependence continuum.     

Concordance of different measures of nicotine dependence: two pilot studies

Two samples of adult daily smokers completed a structured interview to determine nicotine dependence according to generic (DSM-IV/ICD-10), Fagerstr?m [Fagerstr?m Tolerance Questionnaire (FTQ), Fagerstr?m Test for Nicotine Dependence (FTND), Heavy Smoking Index (HSI), and time to first cigarette after awakening (TFC)], consumption [e.g., cigarettes/day (CPD)], and self-rating (e.g., "how addicted are you") measures. One sample was a population-based sample of 43 smokers from the Vermont site of the DSM-IV field trial for substance use disorders. The other sample consisted of 50 smokers evenly distributed across a wide range of CPD to study biochemical markers of smokers. In the first study, DSM/ICD criteria were only slightly correlated with Fagerstr?m (r =.24-.35) and consumption (r =.06-0.33) criteria. Self-rating criteria were correlated moderately with most other criteria (r =.24-.60). In the second study, generic, Fagerstr?m, and self-rating criteria increased with increasing CPD up to 30 CPD but not thereafter. One interpretation of these results is that generic, Fagerstr?m, consumption, and self-rating criteria each tap different aspects of nicotine dependence.     

The Fagerström test for nicotine dependence in two adult population samples-potential influence of lifetime amount of tobacco smoked on the degree of dependence

BACKGROUND: The Fagerstr?m test for nicotine dependence (FTND) has been widely used in clinical samples but seldom in population samples. Data are particularly lacking for a large range of ages. The goal was to describe the FTND sum score distribution in the adult population and to show potential variation according to the number of years of smoking. METHODS: Random adult population samples from two northern areas in Germany were used. Sample 1 included 1460 current smokers aged 20-64 years and sample 2 included 1135 current smokers aged 20-79 years. One cross-sectional and longitudinal and one cross-sectional study were conducted. The FTND was administered during face-to-face computer-aided interviews. RESULTS: The mean FTND sum score for those aged 20-64 was 3.2 among sample 1 and 2.5 among sample 2. The number of years of smoking and age did not affect the FTND sum score whereas it was positively correlated with the lifetime amount of tobacco smoked. CONCLUSIONS: Dependence according to the FTND does not increase with the number of years of smoking. Population-based interventions addressing the needs of dependent smokers across all age groups are needed.     

Exploring brief measures of nicotine dependence for epidemiological surveys

A score > or = 6 in the Fagerstr?m Test for Nicotine Dependence (FTND), identifying high nicotine dependence, was compared with three briefer classifications: (1) Item 4: heavy smoking (more than 30 cigarettes per day); (2) Item 1: high early smoking (smoking within 30 min of waking up); and (3) a score > or = 4 by combining Items 1 and 4. The FTND scores from 1642 smokers from five samples in the US and Spain were analyzed. Heavy smoking had low sensitivity. High early smoking had low specificity. A score > or = 4 by combining Items 1 and 4 had relatively good sensitivity (94%) and specificity (88%). Researchers needing definition of nicotine dependence briefer than FTND may want to only use Items 1 and 4 of FTND with a cutting score > or = 4.     

The Fagerstrom Test for Nicotine Dependence and the Diagnostic Interview Schedule: do they diagnose the same smokers?

Two common assessment tools for nicotine dependence are the Fagerstrom Test for Nicotine Dependence (FTND) and the Nicotine Dependence section of the Diagnostic Interview Schedule [(DIS)-III-R or -IV based on the Diagnostic and Statistical Manual (DSM)-III-R and -IV, respectively]. The FTND emphasizes morning smoking and overall "heaviness" of smoking. The DSM emphasizes adverse consequences, desire to cut down, and mood changes during withdrawal. We tested (1) how the DSM-III-R diagnosis of Nicotine Dependence is related to FTND score; and (2) how the (a) DSM-III-R or (b) elevated FTND score is related to longer smoking histories, greater psychiatric symptomatology, and tobacco liking scores. Retrospective chart reviews were conducted on 370 smokers, the majority (55.9%) of whom had a current DSM-III-R diagnosis of Substance Dependence other than nicotine. All subjects had completed the FTND, the DIS-III-R, the Symptom Checklist-90-Revised (SCL-90-R), and a survey on drug liking. Agreement statistics were calculated between the DSM-II-R diagnosis of Nicotine Dependence and various cutoff scores values that were assigned as thresholds for nicotine dependence on the FTND. At no cutoff score did the two instruments reliably agree; the highest kappa (at a cutoff of FTND > or = 7) was 0.205. At cutoffs above 5, the FTND diagnosed fewer cases than the DSM-III-R. Multiple regression analysis showed that DSM diagnosis was associated with greater psychiatric symptomatology on the SCL-90-R, while FTND scores were associated with greater tobacco liking. The FTND and the DSM-III-R appear to measure different aspects of the tobacco dependence process. Specifically, the FTND may provide a stronger measure of physical dependence, while the DSM may tap other domains such as awareness of dependence, behaviors resulting from that awareness, and psychiatric symptomatology. Disagreements between the FTND and the DSM are likely to become greater with the changes in the DSM-IV.     

Comparison of the Heavy Smoking Index and of the Fagerstrom Test for Nicotine Dependence in a sample of 749 cigarette smokers

Nicotine Dependence (FTND) was administered to a sample of 749 adult smokers. The Heavy Smoking Index (HSI) which combines two items of the FTND (the number of cigarettes per day and the time of the first cigarette of the day) was compared to the FTND. A cut-off score equal or greater than 4 on the HSI detected a similar rate of nicotine dependence as a cut-off score equal or greater than 6 on the FTND. HSI had good sensitivity (79.5%) and specificity (96.5%). The concordance between the two instruments was high (Cohen's kappa=0.74). The HSI performed as well on men as on women. The HSI provides a good measure of high nicotine dependence, particularly appropriate for epidemiological surveys.     

Association of withdrawal features with nicotine dependence as measured by the Fagerström Test for Nicotine Dependence (FTND)

The aim of this study was to advance our understanding of how nicotine dependence level, defined by the Fagerström Test of Nicotine Dependence (FTND), relates to nicotine withdrawal features. We classified nicotine dependence in two categories, 1) low dependence (LD; FTND < 4) and 2) high dependence (HD; FTND ≥ 4). A sample of 241 smokers was recruited via newspaper ads and public notices. Using a multivariate response model with adjustments for age, sex, age at first cigarette, race, and current or lifetime depression, we observed a small to modest statistically robust association between nicotine dependence level and withdrawal features such as, irritation/anger (adjusted relative risk, aRR = 1.2; 95% CI 1.0, 1.3); nervousness (aRR = 1.3; 95% CI 1.1, 1.6); restlessness (aRR = 1.2; 95% CI 1.1, 1.4); difficulty concentrating (aRR = 1.3; 95% CI 1.1, 1.7); and trouble sleeping (aRR = 1.8; 95% CI 1.2, 2.6). Our findings are consistent with the inference that the FTND measures “physiological dependence” and that multidimensional approaches are needed to capture the full range of smoking phenotypology.     

Comparing the validity of the Cigarette Dependence Scale and the Fagerström Test for Nicotine Dependence

BACKGROUND: We compared the validity of the Cigarette Dependence Scale (CDS-12) and of the Fagerstr?m Test for Nicotine Dependence (FTND) in daily cigarette smokers. METHODS: Internet survey in 2004-2007. Eight days and 6 weeks after answering these two dependence questionnaires, participants indicated their smoking status and answered the Cigarette Withdrawal Scale and the Smoking Self-Efficacy Questionnaire. We used the Mini International Neuropsychiatric Interview (MINI) to assess nicotine dependence as defined in DSM-IV. RESULTS: There were 13,697 participants at baseline, 1113 (8%) after 8 days and 435 (3%) after 6 weeks. CDS-12, but not FTND, predicted smoking cessation after 8 days (odds ratio=1.20 per standard deviation unit, p=0.03) and 6 weeks (odds ratio=1.34, p=0.01). In participants who had quit smoking after 8 days, CDS-12 was a better predictor of craving (beta=0.30, p<0.001), than FTND (beta=0.14, p<0.01). After 8 days, self-efficacy in quitters was predicted by CDS-12 (beta=-0.16, p=0.02), but not by FTND (beta=-0.05, p=0.3). CDS-12 was more strongly associated than FTND with DSM-defined dependence measured by MINI: area under the Receiver Operating Characteristic (ROC) curve=0.72 (95% confidence interval=0.70-0.73). For FTND, the area under ROC=0.64 (0.63-0.66). CONCLUSIONS: CDS-12 performed better than FTND on tests of predictive and construct validity.     

Income as a moderator of psychological stress and nicotine dependence among adult smokers

BackgroundPerceived stress and psychological distress are associated with more cigarette craving and withdrawal, higher nicotine dependence, and less success during quit attempts. Low income smokers have disproportionately higher rates of smoking and may be particularly vulnerable to the effects of stress on smoking dependence. The aim of the current study was to assess if lower income smokers have a stronger association between stress and nicotine dependence than higher income smokers.MethodsData were obtained from the Pennsylvania Adult Smoking Study, which included 351 daily smokers. Subjects completed PhenX Toolkit and other self-report measures of socioeconomic factors, the 10-item Perceived Stress Scale, Kessler Psychological Distress Scale (K6), Fagerstrom Test for Nicotine Dependence (FTND), and the Hooked on Nicotine Checklist (HONC). Moderation analyses using linear regression examined income-related differences in the association between stress and nicotine dependence.ResultsIncome groups were categorized by an annual household income of $50,000 based on visual-inspection of scatter plots of income by nicotine dependence. Compared to higher income smokers, lower income smokers had significantly higher mean levels of nicotine dependence on the FTND [3.74 vs. 4.79, p < 0.001], perceived stress [15.63 vs. 17.95, p = 0.004], and psychological distress [5.30 vs. 6.86, p = 0.001], respectively. There were interaction effects, such that lower income smokers had a strong, positive associations between FTND and perceived stress (B = −0.11, CI = −0.17 to −0.04, p = 0.002) and psychological distress (B = −0.13, CI = −0.25 to −0.02, p = 0.022) whereas no association was found in higher income smokers. No significant moderation effects were found for the HONC or when income groups were categorized by U.S. federal poverty level.ConclusionsThe results highlight that the relationship between increasing stress and FTND was found in lower but not higher income groups. Future research should examine socioeconomic, environmental and psychosocial factors that may facilitate increased smoking during stress-induced craving.     

The Fagerström Test for Nicotine Dependence in a Dutch sample of daily smokers and ex-smokers

We explored the performance of the Fagerström Test for Nicotine Dependence (FTND) in a sample of 1378 daily smokers and 1058 ex-smokers who participated in a survey study of the Netherlands Twin Register. FTND scores were higher for smokers than for ex-smokers. Nicotine dependence level was not associated with age. FTND score was highly correlated with the maximum number of cigarettes smoked (even after excluding the item ‘number of cigarettes per day’ from FTND), but the FTND score showed a low correlation with age of first cigarette and total number of years smoked. In a subsample of smokers (n=143) and ex-smokers (n=181) the test–retest correlations for the FTND were high. In general, the performance of the FTND in ex-smokers was comparable with that in smokers. These findings suggest the FTND to be a valuable tool for studies of nicotine dependence in large epidemiological samples.     

Ethnic variation in CYP2A6 and association of genetically slow nicotine metabolism and smoking in adult Caucasians

Genetically variable CYP2A6 is the primary enzyme that inactivates nicotine to cotinine. Our objective was to investigate allele frequencies among five ethnic groups and to investigate the relationship between genetically slow nicotine metabolic inactivation and smoking status, cigarette consumption, age of first smoking and duration of smoking. Chinese, Japanese, Canadian Native Indian, African-North American and Caucasian DNA samples were assessed for CYP2A6 allelic frequencies (CYP2A6*1B-*12,*1x2). Adult Caucasian non-smokers (n = 224) (1-99 cigarettes/lifetime) and smokers (n = 375) (> or = 100 cigarettes/lifetime) were assessed for demographics, tobacco/drug use history and DSM-IV dependence and genotyped for CYP2A6 alleles associated with decreased nicotine metabolism (CYP2A6*2, CYP2A6*4, CYP2A6*9, CYP2A6*12). CYP2A6 allele frequencies varied substantially among the ethnic groups. The proportion of Caucasian slow nicotine inactivators was significantly lower in current, DSM-IV dependent smokers compared to non-smokers [7.0% and 12.5%, respectively, P = 0.03, odds ratio (OR) = 0.52; 95% confidence interval (CI) 0.29-0.95]; non-dependent smokers showed similar results. Daily cigarette consumption (cigarettes/day) was significantly (P = 0.003) lower for slow (21.3; 95% CI 17.4-25.2) compared to normal inactivators (28.2; 95% CI 26.4-29.9); this was observed only in DSM-IV dependent smokers. Slow inactivators had a significantly (P = 0.03) lower age of first smoking compared to normal inactivators (13.0 years of age; 95% CI 12.1-14.0 versus 14.2; 95% CI 13.8-14.6), and a trend towards smoking for a shorter duration. This study demonstrates that slow nicotine inactivators are less likely to be adult smokers (dependent or non-dependent). Slow inactivators also smoked fewer cigarettes per day and had an earlier age of first smoking (only dependent smokers).     

A comparison of the content-, construct- and predictive validity of the cigarette dependence scale and the Fagerström test for nicotine dependence

BACKGROUND: Research showed that the widely used Fagerstrom test for nicotine dependence (FTND) does not cover important aspects of dependence. A new test, the cigarette dependence scale (CDS-12), covers the main elements in DSM-IV and ICD-10 definitions of dependence. We compared the psychometrics of CDS-12, FTND, and CDS-5 and the heaviness of smoking index (HSI), which are short versions of CDS-12 and FTND, respectively. METHODS: Internet survey in 2002-2003. Participants were invited one month after answering the first survey to answer a second survey on smoking status and withdrawal symptoms. RESULTS: Eight hundred two smokers answered both surveys. Cronbach's alpha coefficients were higher for CDS-12 (0.91) and CDS-5 (0.77) than for FTND (0.68) and HSI (0.63). Among 231 smokers who quit smoking at follow-up, higher baseline CDS-12 scores predicted higher withdrawal ratings at follow-up, for all withdrawal symptoms except appetite. FTND and HSI predicted higher craving in quitters, but did not predict the intensity of other withdrawal symptoms. Neither CDS-5, FTND or HSI predicted smoking cessation, but higher CDS-12 scores marginally predicted smoking cessation at follow-up (area under the receiver operating characteristic (ROC) curve = 0.55, 95% confidence interval = 0.51-0.59). CONCLUSIONS: CDS-12 had better content validity and internal consistency than FTND and was a slightly better predictor of withdrawal symptoms. Unexpectedly, higher (not lower) CDS-12 scores predicted subsequent smoking cessation, perhaps because endorsement of some CDS-12 items implies accepting that one is dependent, which in turn could reflect motivation to quit. CDS-12 may represent an alternative to FTND for measuring cigarette dependence.     

Monoamine oxidase polymorphisms and smoking behaviour in Japanese

Although nicotine dependence is one of the primary reasons why smokers cannot quit smoking, nicotine cannot explain all of the psychopharmacological effects of tobacco smoke. Accumulating evidence points to potent inhibition of monoamine oxidase (MAO) which metabolizes neurotransmitters relating to additive behaviour. We have therefore investigated the association between smoking behaviour and MAO ( variable number of tandem repeat in the promoter region and A644G) polymorphisms. The genotypes were examined in 504 Japanese outpatients (217 men and 287 women) who visited Aichi Cancer Centre Hospital. The age-adjusted odds ratios (aORs) were estimated by a logistic model. Among males, we did not find a significant association of the smoking habit with either of the polymorphisms. The median Fargastrom test for nicotine dependence (FTND) score among male current smokers was significantly higher with than without the 4-repeat allele (5.8 and 4.7, respectively). The aOR of FTND 6 versus FTND 6 was 2.72 (95% confidence interval 1.13-6.50) for males with the 4-repeat allele. Among females, the aOR of being current smokers compared to never smokers was 0.49 (0.26-0.93) for individuals with the 4-repeat allele. Our results indicate that the polymorphisms of influence the smoking habit for female, as well as the nicotine dependence and smoking initiation for male smokers. These findings among male smokers support the view that MAO affects a smokers' requirement for nicotine and may explain why some people are predisposed to tobacco addiction and why some individuals find it difficult to stop smoking.     

Nicotine use and dependence and their association to psychiatric disorders in a large sample of adolescent psychiatric inpatients

The purpose of this research was to evaluate the level of nicotine dependence (ND) and to examine its association to psychiatric disorders in a representative clinical sample of adolescent psychiatric inpatients. The modified Fagerstrom Tolerance Questionnaire (mFTQ) was used to assess the level of ND. Psychiatric DSM-IV diagnoses were obtained by using the Schedule for affective disorder and schizophrenia for school-age children (K-SADS-PL). Of the total of 342 inpatients in the study sample, 259 (75.7%) reported to be current smokers. A sum score 6 or higher in the mFTQ, indicating a high level of ND, was found in 37.9% of all smokers. An increased likelihood for high level of ND was associated with substance related disorders (OR 5.1, 95% CI 2.8-9.3), conduct disorder and oppositional defiant disorders (OR 2.4, 95% CI 1.4-4.4). The usefulness of mFTQ in measuring ND among adolescent inpatients is apparent. Therefore, it can be recommended to be used as a routine screening instrument for ND among adolescents hospitalized due to psychiatric disorders.     

Smoking,nicotine dependence and nicotine intake by socio-economic status and marital status

Introduction

Low socio-economic status (SES) is strongly related to smoking, but studies examining the association of SES with nicotine dependence (ND) are scarce. The aim of this study was to examine the associations of SES and marital status with smoking, multiple measures of ND, and cotinine as a nicotine intake biomarker.

Methods

The sample comprised 1746 ever smokers, sampled from the National FINRISK 2007 Study, who had completed a tobacco specific questionnaire in addition to the standard clinical examination. The Fagerström Test for Nicotine Dependence (FTND), the Heaviness of Smoking Index (HSI), the Nicotine Dependence Syndrome Scale (NDSS), and the Hooked On Nicotine Checklist (HONC) were assessed, while plasma cotinine was measured as a biomarker of nicotine exposure in daily smokers. Univariate and multivariate associations were assessed by linear regression and multinomial logistic regression.

Results

In multivariate models, lower education was associated with higher FTND and HSI, income with HSI, and occupation with HSI (men only), FTND, HONC and NDSS scores. Lower education was related to higher cotinine levels among daily smokers, although the association diminished slightly after adjusting for daily smoking amount. Living without a spouse was associated with daily smoking and higher ND.

Conclusion

In this cross-sectional study low SES was linked with higher ND among current smokers, while low SES was associated with higher cotinine levels among daily smokers. Living alone was linked with higher ND. Longitudinal studies are warranted to further explore these associations. As lower SES smokers are more addicted they may need more targeted cessation services to succeed in quitting smoking.