The Author 2007. Published by Oxford University Press on behalf of the Medical Council on Alcohol.
Tobacco use is associated with more severe alcohol dependence, as assessed by the number of DSM-IV criteria, in Swedish male type 1 alcoholics
1 Sahlgrenska Academy at Göteborg University, Institute of Neuroscience and Physiology, Section of Psychiatry, Sahlgrenska University, Hospital/Mölndal, The Göteborg University
2 Psychiatric Clinic Kungälv Hospital, Göteborg University
3 Department of Psychology, Göteborg University, Sweden
* Author to whom correspondence should be addressed at: Department of Psychology, Göteborg University, P. O. Box 500, SE-405 30 Göteborg, Sweden. Tel: 46-31-7734289; Fax: 46-31-7734628; E-mail: Claudia.Fahlke{at}psy.gu.se
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ABSTRACT |
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Background: A high smoking prevalence has been reported in treatment-seeking alcohol-dependent individuals. It has also been suggested that alcohol-dependent individuals who smoke may have a more severe course and greater severity of their alcoholism. Methods: This study evaluated the impact of tobacco use in 108 Swedish male type 1 alcohol-dependent individuals, recruited by advertisement in a local daily newspaper. They were sub-grouped into smokers (N = 50), snuffers (N = 12) and tobacco nonusers (N = 46). The number of criteria for the diagnosis of alcohol dependence was used to assess the severity of alcohol dependence. Results: The smokers were significantly younger compared to the tobacco non-using group, and also younger at their onset of excessive alcohol consumption. Both smokers and snuffers fulfilled significantly more DSM-IV criteria for alcohol dependence than tobacco nonusers. Furthermore, significantly higher proportions of smokers and snuffers fulfilled the criteria no 2 (experiencing withdrawal syndrome) and no 7 (continuing to use alcohol despite problems). Conclusions: These findings indicate that not only smoking, but also snuffing, is associated with greater severity of alcohol dependence, as reflected by the greater number of DSM-IV criteria.
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Introduction |
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A smoking prevalence, as high as 80–90%, has been reported in treatment-seeking alcohol-dependent individuals (Bien and Burge, 1990
; Batel et al., 1995; Gulliver et al., 1995; Hughes, 1996; Daeppen et al., 2000). The smoking prevalence in alcohol-dependent individuals thus widely exceeds that in the general population (Bien and Burge, 1990). Alcohol-dependent individuals are also far more likely to smoke heavily in comparison to non alcohol-dependent smokers (Bien and Burge, 1990). It is well recognized that smoking and alcohol consumption each have their detrimental health effects, such as increased risk of cancer and other physical disorders, and it has also been estimated that the combined health risk of smoking and alcohol consumption may be 50% higher than the sum of their independent risk (Bien and Burge, 1990). It has also been shown that alcohol-dependent individuals who smoke have a more severe course and greater severity of their alcohol dependence (Daeppen et al., 2000; John et al., 2003). This could, however, be an indirect reflection of the presence of additional clinical characteristics such as antisocial personality disorder (ASPD) and other drug dependencies or even reflect gender differences. However, Daeppen et al. (2000) have shown that, when the impact of gender, ASPD and additional drug dependencies has been taken into consideration, both current smokers and nicotine-dependent smokers show evidence of a greater number of alcohol-related problems.
The aim of the present study was to evaluate the impact of tobacco use (smoking and also use of smokeless tobacco, i.e. snuffing) in Swedish male type 1 (Cloninger et al., 1981, 1996) alcohol-dependent individuals. The number of criteria for the diagnosis of alcohol dependence was used to assess the severity of alcohol dependence. The validity of this measure of severity of alcohol dependence has been shown by Feingold and Rounsaville (1995); Langenbucher et al. (1996) and Gelernter and Kranzler (1999). Thus, Langenbucher et al. (1996) have shown that the number of the DSM-IV criteria or scores of Addiction Severity Index (ASI) and Alcohol Dependence Scale (ADS) are positively correlated. These authors concluded that the three measures (i.e. number of DSM-IV criteria, ASI and ADS scores) clearly tap a common dimension, the symptomatic severity of alcohol dependence (Langenbucher et al., 1996). The authors also suggested that the association between these scales may allow scholars to compare studies that use different dependence measures (Langenbucher et al., 1996). Type 1 alcohol-dependent individuals were studied since the use of this typology most likely eliminates the influence of ASPD. Thus, the other type of alcohol dependence according to this typology is the so called type 2 alcoholism which is characterized by early onset (25 years or earlier) of alcohol-related problems and antisocial behaviour. It has been suggested that type 2 alcoholism rather represents a dual diagnosis of ASPD and alcohol dependence (Schuckit and Irwin, 1989). All subjects in this study were examined with urine toxicology screen tests to eliminate additional ongoing drug use. Since all subjects were of male gender the influence of gender differences was also eliminated. Finally, since many of the subjects had no history of earlier treatment for alcoholism or alcohol-related problems it was also possible to estimate the prevalence of tobacco use in a group of never-treated alcohol-dependent individuals. This may be of importance since it has been suggested that studies using data from inpatient populations may give a skewed picture of the clinical characteristics of alcohol dependence (Raimo et al., 1999).
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Methods |
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Subjects
Male subjects aged 25 to 65 years were recruited by advertisement in a regional daily Swedish newspaper, which predominantly covers the south-western part of Sweden. The advertisement was designed to recruit subjects for investigating pharmaco-therapeutical interventions on excessive alcohol intake (Balldin et al., 1994
, 2003; Eriksson et al., 2001a,b). A total number of 367 subjects responded to the advertisement and were thereafter interviewed. The subjects were considered eligible for the present study if they had fulfilled the DSM-IV criteria for alcohol dependence and could report their current status of tobacco use. They had to be socially stable, i.e. employed, or living on a pension and with a permanent place of residence and be without physical or psychiatric disorders not associated with excessive alcohol consumption or comorbid with alcohol dependence. Their weekly alcohol consumption had to be above 300 g of pure alcohol. Finally, subjects should not have diagnoses of abuse or dependence of substances other than alcohol and nicotine.
Study design
The individuals were examined physically and psychiatrically by an experienced psychiatrist of an alcoholism treatment unit at a University Hospital using a semi-structured interview. This interview included, thorough questioning of the subjects for the presence or absence of the DSM-IV criteria (American Psychiatric Association, 1994) for alcohol dependence occurring at any time during the last year. The subjects had to meet at least three of the seven DSM-IV criteria for alcohol dependence to receive this diagnosis. The subjects were furthermore thoroughly evaluated whether they fulfilled the criteria for type 1 or 2 alcoholism (Cloninger et al., 1981, 1996), using the criteria of von Knorring et al. (1985). When using subtypes to classify alcohol-dependent subjects it has been emphasized that it is important to use DSM-IV or ICD 10 criteria to establish the initial diagnosis of alcohol dependence (Lesch and Walter, 1996).
Biochemical tests
Blood samples were collected for determination of carbohydrate deficient transferrin (CDT; upper laboratory reference limit 1.5%) and liver function tests (aspartate aminotransferase (AST), alanine aminotransferase (ALT) and gamma-glutamyltransferase (GGT); upper laboratory reference limit for all tests: 0.8 µK at/L or 48 Units/L). Determination of presence of illicit drugs (cannabis, amphetamine and opiates) and/or bensodiazepines in urine samples was also performed using suitable laboratory screening procedures.
Alcohol consumption and tobacco use
During 2 weeks prior to the investigation, the subjects had to record their daily alcohol consumption on a self-monitoring form called alco-card (for details see Balldin et al., 1994). They were also requested to estimate for how long a time-period (in years) they had had an excessive level of alcohol consumption. Thereafter, the subjects' age at onset of the excessive alcohol consumption was calculated and recorded. Excessive alcohol consumption was defined as consuming more than three standard drinks of alcohol (about 40 g of pure alcohol) per day (Miller et al., 2005). Past year smoking status was registered as number of cigarettes used per day and snuffing (i.e. tucking snuff under the lip) as amount (grams) of snuff used daily.
Data analyses
The alcohol-dependent subjects were sub-grouped according to their status of tobacco use, i.e. smokers, snuffers and tobacco nonusers. Analysis of variance (ANOVA) was used to detect an overall effect and Fisher's Protected Least Significant Difference (PLSD) was used for post-hoc comparisons between the groups. Differences in number of individuals fulfilling the various DSM-IV criteria for alcohol dependence were analyzed using 
2-test. The data are presented as mean ± SD.
This study was approved by the Ethics Committee of the Göteborg University, Sweden and was in compliance with the Helsinki Declaration of 1975. Informed consent was obtained from all subjects. None of the subjects were paid for their participation in the study.
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Results |
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A total of 108 male type 1 alcohol-dependent individuals fulfilled the inclusion/exclusion criteria and were consequently included in the study. None of them had a history of treatment as inpatient for alcohol-related problems and 86 (80%) had no earlier history of treatment for alcoholism or alcohol-related problems. No one had positive urine toxicology screen tests for cannabis, amphetamine, opiates or benzodiazepines.
The subjects were sub-grouped according to their status of tobacco use: smokers (N = 50; 46%), snuffers (N = 12; 11%) and tobacco nonusers (N = 46; 43%). The smokers used 20 ± 10 cigarettes per day and the snuffers 42 ± 21 grams snuff per day. None of the subjects reported combined use of cigarettes and snuff.
As seen in Table 1, the alcohol-dependent individuals who were smokers were significantly younger compared to the tobacco non-using group at the time of the investigation (P < 0.02). They were also younger at their onset of excessive alcohol consumption compared to the tobacco nonusers (P < 0.03). However, there were no significant differences between the three study groups in number of years of excessive alcohol intake or in alcohol consumption during the 2 weeks before investigation. Nor was there any significant overall effect among the three groups in any of these parameters.
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The liver function test revealed a significant overall effect for AST (P < 0.05, F = 3.36) and for ALT (P < 0.05, F = 3.36). Moreover, there was a significant between-group difference in AST and ALT. Thus, the smokers had lower levels of AST and ALT compared to tobacco nonusers and to snuffers (P < 0.05 for each comparisons).
The percentage of subjects in the three study-groups who fulfilled the various DSM-IV criteria for alcohol dependence is shown in Table 2. There was a significant overall effect in the total number of DSM-IV criteria for alcohol dependence among the three groups (P < 0.02, F = 4.2). Both the smoking and snuffing alcohol-dependent individuals fulfilled more of the DSM-IV criteria for alcohol dependence than the tobacco non-using group (P < 0.02 and P < 0.05, respectively). Furthermore, significantly higher proportions of smokers and snuffers fulfilled the DSM-IV criteria no 2 (experiencing withdrawal syndrome) and no 7 (continuing to use alcohol despite problems) for alcohol dependence, compared to tobacco nonusers (P < 0.01, 2 = 8.36 and P < 0.001, 2 = 13.28, respectively).
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Discussion |
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In the present study of 108 socially stable male type 1 alcohol-dependent individuals, the current smokers were found to have an earlier onset of excessive alcohol consumption compared to tobacco non-using individuals. Furthermore, the current tobacco users, i.e. both smokers and snuffers, fulfilled more of the DSM-IV criteria for alcohol dependence. Thus, the findings in the present study support the notion from earlier studies that current smoking in alcohol-dependent individuals is associated with severity of alcohol dependence (Daeppen et al., 2000
; John et al., 2003). The findings further suggest that the use of smokeless tobacco, i.e. snuff, is associated with greater severity, i.e. more dependence criteria for alcohol dependence. Interestingly, the findings of more DSM-IV criteria for alcohol-dependent tobacco users, i.e. current smokers and snuffers, was mainly explained by an increased prevalence of the DSM-IV criteria numbers 2 and 7 for alcohol dependence.
With respect to the association of tobacco use and the DSM-IV criteria no 2 for alcohol dependence, i.e. withdrawal syndrome, it is unclear whether tobacco use predisposes for the development of alcohol withdrawal symptoms or is a consequence of the presence of such symptoms. The latter possibility cannot be disregarded since smoking appears to have paradoxical effects in producing both a calming effect and simultaneously sympathetic arousal (Pomerleau and Pomerleau, 1987). It is therefore possible that some individuals may use smoking as a way of ‘self-medication’ in alcohol withdrawal to primarily reduce psychic anxiety although smoking may actually worsen other symptoms in alcohol withdrawal by causing an increase in sympathetic activity manifesting itself as tachycardia, tremor and sweating. The findings of similar duration of excessive alcohol consumption in tobacco using and tobacco non-using individuals, but more frequent reports of alcohol withdrawal symptoms in tobacco users may suggest that tobacco use causes a more rapid progression into the late phase of alcohol dependence, which is predominated by features of physiological withdrawal (Kumar et al., 2005). However, an alternative explanation may be that smokers consume a larger amount of alcohol at the onset of their alcohol consumption.
Regarding the association between tobacco use and the DSM-IV criteria no 7 for alcohol dependence, i.e. continuing to use alcohol despite knowledge of psychiatric or somatic problems, it should be noted that in a sub-sample of the present subjects, examined for the status of central serotonergic neurotransmission (N = 37), tobacco use (smoking or snuffing) was associated with reduced serotonergic neurotransmission, as assessed by the prolactin response to D-fenfluramine (Berggren et al., 2003). It is thus possible that a reduced central serotonergic neurotransmission is pre-existing in tobacco using alcohol-dependent individuals and may predispose for earlier onset and greater severity of alcoholism but also to concomitant tobacco use as well as to the increase in risk-taking behaviour (reflected in criteria no 7) in these individuals. It should, in this context, be noted that common genetic vulnerability for nicotine and alcohol dependence has been reported in males, although the biological mechanisms are not known (True et al., 1999). On the other hand, in animal studies, chronic nicotine treatment has been shown to induce behavioural disinhibition, which may be associated with nicotine-induced reduction in central serotonergic neurotransmission. (Olausson et al., 1999). It may thus be that tobacco, and consequently nicotine use in alcohol-dependent individuals may cause behavioural disinhibition, which may then reflect itself in risk-taking behaviours such as those described in the DSM-IV criterion for alcohol dependence, i.e. alcohol is used in spite of knowledge of negative consequences. Yet another possibility may be that tobacco using alcohol-dependent individuals may have a more episodic pattern of alcohol intake (binge drinking) and may therefore be more prone to develop withdrawal after the end of each alcohol intake episode. Finally, it should be noted that nicotine-dependent individuals who are also alcohol-dependent, fulfill more DSM-IV nicotine-dependence criteria than those without concomitant alcohol dependence (Marks et al., 1997). The nicotine-dependence criteria thus reported more frequently by the alcohol-dependent individuals in that study were: (i) using nicotine in larger amounts or over a longer time than intended, (ii) continued use despite problems caused or exacerbated by nicotine, (iii) marked tolerance and (iv) experiencing characteristic nicotine withdrawal symptoms (Marks et al., 1997). In addition, Batel et al. (1995) have reported a correlation between the severity of alcohol and nicotine dependencies. Consequently, alcohol and nicotine dependencies may reciprocally influence and increase the severity of each other.
In the present study, the smoking prevalence was 46% (the prevalence of tobacco use was 57% if snuffers were included), which is lower than that of 80–90% reported for treatment-seeking alcohol-dependent individuals (Bien and Burge, 1990; Batel et al., 1995; Gulliver et al., 1995; Hughes, 1996; Daeppen et al., 2000). The majority (about 80%) of the alcohol-dependent individuals in the present study had no history of earlier treatment for alcohol dependence or alcohol-related problems. It is therefore possible that the prevalence of smoking and tobacco use is lower in alcohol-dependent individuals with no history of treatment for their alcoholism in comparison to those with earlier histories of out- or inpatient treatment. If so, the reason for this difference may be that alcohol-dependent individuals who are smokers or snuffers may, according to the findings in the present study, be more likely to experience alcohol withdrawal symptoms and thus be in greater need for establishing contact with out- or inpatient treatment units for help with management of alcohol withdrawal symptoms. Consequently, the prevalence of tobaccouse would be higher in out- or inpatient treatment samples of alcohol-dependent individuals than in those with no history of alcohol treatment.
In the present study, we also found that there was a long time-lag, about 11 to 12 years, between reports of start of excessive alcohol consumption until the time when the individuals actually sought help, i.e. in this case responding to an advertisement for participating in studies of excessive alcohol consumption. This finding is in agreement with earlier studies of a long time-lag of about a decade between start of alcohol-related problems, the recognition that a problem exists and actually seeking treatment (Schuckit et al., 1995; Berglund et al., 2006).
Finally, there are a number of limitations in the present study that ought to be mentioned. First, the number of alcohol-dependent individuals is relatively low, particularly for users of smokeless tobacco, i.e. snuffers, and conclusions particularly for this group should therefore be drawn with caution. It should, in this context, be noted that in northern Sweden there has, in recent years, been a transition from smoking to the use of smokeless tobacco, i.e. snuff, amongst men (Rodu et al., 2002). Younger men, thus, may use snuff to achieve smoking cessation, i.e. smoking is replaced with snuffing. It has been suggested that the transition in tobacco use from smoking to snuff may confer substantial health advantages, since snuff does not appear to be associated with smoking-related cancers and does not appear to be a strong risk factor for cardiovascular diseases (Rodu et al., 2002). Thus, if in the future, there may be an increasing trend in the transition from smoking to products of smokeless tobacco (i.e. snuff), as marketed by some tobacco companies. It is therefore of importance to clarify the influence of using smokeless tobacco on the course and severity of alcohol dependence. Second, the alcohol-dependent individuals in the present study were only questioned for their past year status of tobacco use and thus no history of tobacco use was taken. It was therefore not possible to study the course and severity of alcohol dependence in former tobacco users and, consequently, the important question whether earlier cessation of tobacco use may alter the course of severity of alcohol dependence could not be addressed in this study. Third, no measures of nicotine dependence were used in the present study. Fourth, only male subjects were studied and the findings can therefore not be generalized to include females. Fifth, the exclusion criterion of comorbid drug use disorders may have produced a non-representative sample of type 1 alcohol-dependent individuals, since alcohol dependence and drug use disorders often are comorbid with each other. For example, in the study of Raimo et al. (1999) 35.7% of never treated alcohol-dependent individuals had additional drug dependency. Finally, it should also be mentioned that in this study, the number of DSM-IV criteria was used to assess the severity of alcohol dependence and scales, such as the ASI or ADS, which are more frequently used and cited in the literature, were not used in this study. Nevertheless, as mentioned earlier, the number of DSM-IV criteria has been shown to be a valid measure of severity of alcohol dependence (Feingold and Rounsaville, 1995; Langenbucher et al., 1996; Gelernter and Kranzler, 1999).
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ACKNOWLEDGEMENTS |
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This study was supported by grants from the Bank of Sweden Tercentenary Foundation (J02-0301:1), the Swedish Alcohol Monopoly Foundation for Alcohol Research (02/3:3), the Västra Götalandsregionens FoU-bidrag (no 22) and the Arbetsmarknadens försäkringsaktiebolag (AFA).
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