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Influence of smoking and drinking habits on salivary cortisol levels
Person. individ. Dijjj
PII: so191-8sfi9(97)ooo93-7
INFLUENCE
Vol. 23, No. 4, pp. 593599, 1997
Q 1997Elsevier Science Ltd.
Pergamon
OF SMOKING AND DRINKING SALIVARY CORTISOL LEVELS
All rights reserved Printed in Great Britain 0191~8869/97 %17.00+0.00
HABITS ON
Josepa Canals,* M. Teresa Colomina, Jose L. Domingo and Edelmira Domenech Department of Psychology and Laboratory of Toxicology and Environmental Health, ‘Rovira i Virgili’ University, Tarragona, Spain, and Department of Health and Social Psychology, Autonomous University. Barcelona, Spain (Receioed 2 January 1997)
Summary-The present study assessed the association of smoking and drinking habits on salivary cortisol levels in a sample of 106 young teenagers. The gender, psychopathological disorders (ICD-10 criteria), and psychological stress variables were considered. Results showed that cortisol levels were significantly higher for moderate to heavy smokers (10 or more cigarettes per day) than for light and non-smokers. This effect was more remarkable in females than in males. Psychopathology was a factor influencing cortisol levels mainly in males. While high stress and elevated daily consumption of cigarettes were significantly associated with salivary cortisol levels. drinking habits did not influence these concentrations. 0 1997 Elsevier Science Ltd
INTRODUCTION
The relationship of the hypothalamic-pituitary-adrenal (HPA) axis with psychopathological disorders and other physiological and psychological factors has been widely investigated (Field, Colditz, Willett, Longcope & McKinlay, 1994; Kiess, Meidert, Dressendiirfer, Schriever, Kessler, Konig, Schwarz & Strasburger, 1995; Kirschbaum, Wtist & Hellhammer, 1992; Steven & Nemeroff, 1994). Tobacco consumption has been accepted as a factor influencing cortisol levels. In relation to it, while Field and co-workers (1994) reported that smoking is more important than other variables such as age, obesity, or dietary intake, Weidenfeld, Bodoff, Saphier and Brenner (1989) suggested that nicotine could be a potent stimulator of the adrenal system which acts through induction of corticotrophin releasing hormone (CRH) release after binding to cholinergic receptors in the hypothalamus. Although in general, data support that subjects smoking cigarettes have higher levels of cortisol than non-smokers (Eliasson, Hagg, Lundblad, Karlsson & Bucht, 1993; Field et al., 1994; Gilbert, Meliska, Welser & Estes, 1994), some investigators reported lower levels of cortisol in smokers than in non-smokers (Handa, Kono, Ishii, Shinchi, Imanishi & Arakawa, 1994). There are several reasons for these contradictory results. For example, psychopathology and smoking cigarettes are frequently associated. More specifically, major depression and anxiety disorders have been related to nicotine dependence (Breslau, 1995). This association is supported by the hypothesis of Gilbert & Welser (1989) and the results of Gilbert and associates (1994) showing that nicotine has antidepressant effects. So depressed smokers would have smaller responses to nicotine than nondepressed smokers. In this sense, while psychopathology could increase adrenal hormone levels, the high cortisol levels in smokers might reduce the behavioral effects of nicotine as well as the binding of nicotine and neurotransmitters to CNS receptors (Pauly, Grun & Collins, 1992). Other variables that could also explain different cortisol levels between smokers and non-smokers are gender, degree of habitual nicotine exposure or tolerance, dose of nicotine, personality traits or stress (Gilbert et al., 1994; Gilbert & Gilbert, 1995). Alcohol consumption has also been studied as a stimulator of the HPA axis. While some investigators (Adinoff, Risher-Flowers, De-Jong, Ravitz, Bone, Nutt, Roehrich, Martin & Linnoila, 1991) suggested that there is a marked increase of the cortisol levels associated with the alcohol withdrawal, other authors did not find similar results. A positive association between alcohol intake and cortisol was recently reported in randomly sampled middle-aged US men (Field et al., 1994).
*To whom all correspondence should be addressed. 593
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Josepa Canals et al.
Ekman, Vakkuri, Vuolteenaho and Leppaluoto (1994) also found higher levels of cortisol in plasma of subjects who received high doses of ethanol than in individuals given placebo. However, other investigators did not find any activation of the HPA axis in individuals given ethanol at doses that caused acute intoxication (Inder, Joyce, Wells, Evans, Ellis, Mattioli & Donald, 1995; Waltman, Blevins, Boyd & Wand, 1993), in subjects receiving lower concentrations of alcohol (Gianoulakis, Krishnan & Thavundayil, 1996) or in subjects with chronic alcoholism (Del Arbol, Aguirre, Raya, Rico, Ruiz-Requena & Miranda, 1995). It is possible that the reaction to alcohol and the cortisol response to this drug are due to individual differences. Chronic alcohol consumption could be related to chronic stress, which could also modify cortisol levels. Wall, Nemeroff, Ritchie and Ehlers (1994) showed significant higher blood cortisol levels in subjects with a genotype related to alcoholinduced flushing than in those with a different genotype. As for smoking habits, depression and minor mental disorders have been also associated with alcohol consumption (Deykin, Levy & Wells, 1986; Madianos, Gefou-Madianou, Richardson & Stefanis, 1995). Thus, psychopathology could modify adrenal hormone levels and reduce the effects of alcohol. Salivary cortisol reflects the fraction of plasma cortisol not bound to proteins. It is a more sensitive indicator of adrenal function than total plasma cortisol (Gutchot, Lepine, Cohen, Fiet, Lemperiere & Dreux, 1987). Moreover, this parameter offers advantages such as non-stressing sampling, the fact that individuals can provide samples by themselves, and that salivary cortisol levels are not modified by estrogens (oral contraceptives) (Kirschbaum & Hellhammer, 1989). To date, no data on the effects of smoking and drinking habits (considering simultaneously gender and psychopathological variables) on salivary cortisol concentrations in the general population have been reported. In the present study we assessed the effects of smoking and drinking habits on salivary cortisol levels in a sample of teenagers. The influence of gender, psychopathological disorders, and psychological stress as possible interacting factors on the salivary cortisol concentrations was also evaluated.
METHOD Subjects
The Ss were young teenagers (17.5-18.5 yr) of a general population living in Reus (Catalonia, Spain) who had participated in a longitudinal study of development and psychopathology since the age of 10-l 1 yr. Although at the beginning of the study 579 children (334 boys and 245 girls) agreed to be included in the study, only 304 could be recruited at the age of 18 yr. Of these, 134 (62 males and 72 females) returned the salivary samples, but cortisol levels were finally evaluated in 106 individuals owing to problems with the sample collection. All participants were called at educational centers and examined. Absent individuals were subsequently recruited by phone or letter. All Ss were singles and living with their families. Smoking and drinking assessment
A self-report questionnaire was elaborated for this research. This questionnaire asked for smoking and/or drinking habits, the age at which they started smoking and drinking, and the kind and amount of alcoholic beverages. Additional information from Schedules for Clinical Assessment in Neuropyschiatry (SCAN, Spanish version) (Wing, Babor, Brugha, Burke, Copper, Giel, Jablenski, Regier & Sartorius, 1990; Wing, Babor, Brugha, Burke, Copper, Giel, Jablenski, Regier & Sartorius, 1993) about how much the Ss smoked and drank, as well as tobacco dependence (wish of smoking cigarettes) was also used. Individuals were divided into three groups according to the number of cigarettes smoked daily: non-smokers (no cigarettes), light smokers (one to nine cigarettes), and moderate to heavy smokers (ten or more cigarettes). In relation to the variable dependence to tobacco, Ss were also distributed into three categories: non-dependence (those who answered ‘no need’), low dependence (‘some controllable need’) and high dependence (‘strongneed and it is difficult to live without tobacco’). To evaluate alcohol consumption Ss were divided into non-drinkers (those who drank never or just ocasionally) and drinkers (those who drank daily or during the weekend). At the age of assessment almost all Ss drank during the weekends.
Salivary cortisol levels
595
Measurement of stressful life events
To collect information on stressful life events during the preceding year, an experimental ‘Adolescent Life Change Event Scale’ (ALCES) form (Yeaworth, York, Hussey, Ingle & Goodwin, 1980) was used. Life change events refer to a number of personal, social, familiar and occupational life changes, which presumably could create stress. The first step includes 31 items on a rating scale from 1 (‘not at all upset’) to 5 (‘extremely upset’). To ascertain if the subject had experienced the event, on the second step of the questionnaire the items were repeated without rating scales. Total stress affecting an individual was calculated by adding all events experienced (second step of the questionnaire) multiplied by the subjective score assigned to each item (first step). Stress levels were designated ‘low’ or ‘high’ when the score was lower or higher than 25, respectively. Psychopathology assessment
Psychiatric diagnoses were made with the Schedules for Clinical Assessment in Neuropsychiatry (SCAN, Spanish version) (Wing et al., 1990, 1993) and based on the ICD-10 criteria. The most frequent diagnoses found were sleep disorders, mood disorders and anxiety disorders (Canals, Domenech, Carbajo & Blade, in press). Diagnoses were generated by a computerized version of SCAN. Based on preliminary results (unpublished data), two groups (total sample and sample without psychopathology) were defined to evaluate the relationship between smoking and drinking habits and cortisol. Cortisol analysis
Salivary samples were collected between 07:OOand 09:OOhr. Each S was asked to collect approximately 2ml of saliva with a syringe and to keep that volume in a polypropylene tube at room temperature for 24 hr. Subsequently, the samples were stored at - 20°C until analysis. Samples were centrifuged at 3000 xg for 5 min to remove mucins and any cellular debris. Salivary cortisol concentrations were determined using the ‘Magic Cortisol’ radioimmunoassay kit (Ciba-Corning, Gieben, Germany) as modified by Kirschbaum, Strasburger, Jammers and Hellhammer (1989) with a sensitivity of 0.1 pg/dl. Each sample was measured in duplicate and averaged. Statistical analysis
Statistical analyses were carried out with the SPSS software package. One-way analysis of variance (ANOVA) was used. Multiple comparisons between groups were conducted with the LSD (least significant difference) test. A correlational method was also used to assess the association between two variables. Differences were considered to be significant at P < 0.05. RESULTS Although the smoking population (n = 42) showed higher cortisol levels (0.569 + 0.25 pg/dl) than the non-smoking population (n = 64) (0.496 + 0.34 pg/dl), the differences between these groups were not statistically significant. In males, salivary cortisol levels were 0.602 +0.23 pg/dl for smokers (n = 22) and 0.523 + 0.42 pg/dl for non-smokers. In turn, although males showed higher salivary cortisol levels than females, the differences between sexes did not reach the level of statistical significance. Table 1 shows the mean salivary cortisol levels for all the Ss according to the daily consumption of cigarettes. Moderate to heavy smoker females showed higher cortisol levels than non-smokers or light smokers, but in males the increases were not statistically significant. However, when Ss with mental disorders were excluded, salivary cortisol levels in males were found to be significantly increased in moderate to heavy smokers as against non-smokers. The correlations between the daily consumption of cigarettes and the salivary cortisol concentrations are presented in Table 2. A higher correlation was found for Ss without psychopathology than for individuals in the total sample. The highest correlation was observed in males without disorders, although the level of statistical significance was only reached for the total population (males and females).
Josepa Canals et al.
596
Table 1. Mean (SD) salivary cortisol levels (pg/dl) according to the daily consumption of cigarettes Males Mean (SD)
Females n
Mean (SD)
All subjects n
Mean
n
Total sample
Non-smokers
0.523’ (0.42)
28
Light smokers
0.570’ (0.31)
Moderate to heavy smokers
0.476” (0.28)
36
0.496’ (0.35)
64
7
0.430 (0.27)
13
0.480 (0.28)
20
0.617” (0.19)
15
0.723b (0.19)
7
0.65W (0.19)
22
Non-smokers
0.396” (0.27)
18
0.448’ (0.26)
24
0.425’ (0.26)
42
Light smokers
0.570”b (0.31)
7
0.482” (0.31)
7
0.52Vb (0.30)
14
Moderate to heavy smokers
0.606b (0.21)
12
0.717” (0.24)
4
0.634” (0.21)
16
Sample without psychopotho1og.v
For each sex, results in the total sample or in the sample without psychopathology not showing a common superscript are significantly different from each other at PcO.05. No differences between sexes were found.
Table 2. Correlation between the daily consumption of cigarettes and salivary cortisol levels Males
P
Females
P
Total
P
Total sample
0.137 II=53
NS
0.220 n=56
NS
0.170 !I= 109
NS
Sample without pathology
0.345 n=37
NS
0.294 n=35
NS
0.285 n=72
<0.05
NS, not statistically significant, P~0.05.
Table 3. Mean (SD) salivary cortisol levels (pg/dl) and smoking dependence Males Mean (SD) Total sample No dependence
Females ”
Mean (SD)
Total n
Mean (SD)
n
0.522” (0.38)
37
0.491’ (0.28)
49
0.504’ (0.32)
86
Low dependence
0.598” (0.17)
7
0.483” (0.320)
6
0.545” (0.25)
13
High dependence
0.727” (0.19)
6
0.870
I
0.747b (0.23)
7
0.438 (0.27)
27
0.484 (0.28)
32
0.463” (0.27)
59
Low dependence
0.598” (0.17)
7
3
0.570” (0.23)
10
High dependence
0.793b (0.26)
3
0.503” (0.36) _
0
0.793b (0.26)
3
Sample without psychopathology No dependence
For each sex, results in the total sample or in the sample without psychopathology not showing a common superscript are significantly different from each other at P~0.05. No differences between sexes were found.
The salivary cortisol levels classified according to cigarette-smoking need are shown in Table 3. Although cortisol concentrations were increased in both males and females with high dependence, significant differences were only observed in males without psychopathology or in the total sample. Table 4 summarizes the salivary cortisol concentrations according to smoking habits and levels of stress. Females classified as moderate to heavy smokers showed non-significantly higher cortisol levels than the non-smokers or light smokers, with the increases being more evident for high stress individuals. In males, although moderate to heavy smokers with high stress showed increased salivary cortisol levels compared with those with low stress, the differences did not reach the level of statistical significance.
Salivary cortisol levels
597
Table 4. Mean (SD) salivary cortisol levels (pg/dl) according to the number of cigarettes and stress levels Females
Males n
Mean (SD) Low
Total n
Mean (SD)
Mean (SD)
n
stress
Non-smokers
0.547 (0.46)
0.385” (0.23)
16
0.490 (0.39)
37
Light smokers
0.570” (0.31)
7
0.375 (0.21)
4
0.499’ (0.29)
II
Moderate to heavy smokers
0.559’ (0.11)
12
0.653” (0.25)
3
0.578’ (0.14)
15
Non-smokers
OSOl” (0.31)
9
0.534” (0.21)
18
0.51 I” (0.23)
25
Light smokers
0.453” (0.28)
7
0.458” (0.30)
9
0.457” (0.30)
9
Moderate to heavy smokers
0.670” (0.07)
2
0.775” (0.15)
4
0.74Ob (0.13)
6
21
High stress
For each sex, results in the total sample or in the sample without psychopathology not showing a common superscript are significantly different from each other at PiO.05. No differences between sexes were found.
Table 5. Salivary cortisol levels (pg/dl) and alcohol consumption Males Mean
Females n
Mean
Total n
Mean (SD)
n
Total sample
Nondrinkers
0.529” (0.33)
27
0.480” (0.27)
21
0.500” (0.29)
68
Drinkers
0.560” (0.35)
23
0.510’ (0.30)
14
0.560 (0.34)
37
Sample without psychopathology Non-drinkers 0.495” (0.29)
21
0.449” (0.25)
22
0.470 (0.27)
47
Drinkers
16
0.590 (0.34)
9
0.532 (0.29)
25
0.499 (0.26)
For each sex, results in the total sample or in the sample without psychopathology not showing a common superscript are significantly different from each other at PcO.05. No differences between sexes were found.
Table 5 shows the salivary cortisol levels for all Ss in relation to alcohol consumption. Although no significant differences between drinkers and non-drinkers could be seen, an increase in salivary cortisol levels was observed in the group of drinker females without psychopathology. DISCUSSION As previously reported (Eliasson et al., 1993; Field et al., 1994) smokers showed higher cortisol levels than non-smokers. When Ss were classified only as smokers and non-smokers, salivary cortisol levels were higher in males than in females. These increases were similar to those observed in the group of non-smokers classified according to sex. However, an important increase of cortisol levels for moderate to heavy smoker females was observed when Ss were distributed according to the number of cigarettes smoked. Salivary cortisol levels were significantly higher in moderate to heavy than in light and non-smoker females, whereas higher cortisol concentrations were also found in moderate to heavy smoker females than in males, These data suggest that the effects of high doses of nicotine on salivary cortisol levels are more evident in females than in males. Smoking habits in males significantly increased cortisol levels only when Ss affected by psychopathology were excluded. This finding shows that psychopathology can be a factor influencing cortisol levels mainly in males, which would be in agreement with the results of previous investigations (unpublished data). In this sense, the correlation between salivary cortisol concentrations
598
Josepa Canals et al.
and the daily consumption of cigarettes was higher in males when psychopathology was excluded. A significant positive correlation for the sample without psychopathology was also found. Although a high dependence on tobacco was associated with higher salivary cortisol levels in males and females, only one woman could be included within the high dependence group. As seen for the daily consumption of cigarettes, cortisol levels were significantly higher for males with a high dependence when mental disorders were excluded. Moreover, Ss in that group were also moderate to heavy smokers. When the sample was divided according to the stress variable, both smoking habits and high stress influenced the salivary cortisol levels in males and females. The increase on salivary cortisol levels indicating a great stress response would support a synergistic effect between stress and tobacco as risk factors in some diseases (e.g. ischaemic diseases). In this sense, Eysenck (1988) reported that smoking affects health negatively only in conjunction with other factors like personality. In relation to sex, although higher cortisol levels in females than in males could be observed as a trend in response to tobacco or high stress, the differences did not reach the level of statistical significance. In turn, higher cortisol concentrations were also observed in moderate to heavy smoker females with low stress. These results would support previous findings about differences between males and females, with psychopathology or with high stress, on salivary cortisol levels (Canals, Colornina, Gallart & Domingo, 1997). In females, cortisol levels seem to be more influenced by external factors (stress, tobacco), while internal factors (psychopathology) would be more relevant in males. As reported by Weinrich, Hardin, Valois, Gleaton, Weinrich and Garrison (1996), the activity of the HPA axis increases in response to stress either alone or interacting with personality and social factors. This fact could contribute to the onset and maintenance of smoking habits among some adolescents. Although the results for alcohol consumption are consistent with data of previous reports (Del Arbol et al., 1995; Gianoulakis et al., 1996), the comparison of the present results with data from other authors should be carefully performed. It should be taken into account that the sample used in the current study concerned a young population (18 yr), whereas in addition almost all the individuals in the group of drinkers consumed alcohol only during the weekend. Moreover, the period of time elapsed between the salivary cortisol sampling and the last alcohol consumption was unknown. On the other hand, the increased cortisol levels in drinker females could be due to a dependent alcohol-stress factor. Consequently, further studies should be carried out in order to corroborate gender differences in response to nicotine, stress and psychopathological disorders and their relationship as risk factors. Acknowledgement-This research was supported by a grant from the ‘Fond0 de Investigation Sanitaria’ (FIS 94/0866). Ministerio de Sanidad y Consumo, Spain.
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Breslau, N. (1995). Psychiatric comorbidity of smoking and nicotine dependence. Behavior Generics, 25,95-101. Canals, J., Colomina, M. T., Gallart, I. & Domingo, J. L. (1997). Stressful events and salivary cortisol. Psychological Reports, 80.305-306.
Canals, J., Domenech, E., Carbajo, G. & Blade, J. (in press). Prevalence of DSM-III-R and ICD-IO psychiatric disorders in a Spanish population of 18 year olds. Acta Psychiatrica Scandinavica. Del Arbol, J. L., Aguirre, J. C., Raya, J., Rico, J., Ruiz-Requena, M. E. & Miranda, M. T. (1995). Plasma concentrations of beta-endorphin, adrenocorticotropic hormone and cortisol in drinking and abstinent chronic alcoholics. Alcohol, 12, 525-529.
Deykin, E. Y., Levy, J. C. & Wells, V. (1986). Adolescent depression, alcohol and drug abuse. American Journal of Public Health, 76, 178-I 82.
Ekman, A. C., Vakkuri, O., Vuolteenaho, 0. & Leppaluoto, J. (1994). Delayed pro-opiomelanocortin activation after ethanol intake in man. Alcohol Clinical and Experimental Research, 18, 1226-1229. Eliasson, M., Hagg, E., Lundblad, D., Karlsson, R. & Bucht, E. (1993). Influence of smoking and snuff use on electrolytes, adrenal and calcium regulating hormones. Acta Endocrinologieal of Copenhagen, 128, 3540. Eysenck, H. J. (1988). The respective importance of personality, cigarette smoking and interaction effects for the genesis of cancer and coronary heart disease. Personality and Individual Differences, 9,453-464.
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Field, A. E., Colditz, G. A., Willett, W. C., Longcope, C. & M&inlay, J. B. (1994). The relation of smoking, age, relative weight, and dietary intake to serum adrenal steroids, sex hormones, and sex hormone-binding globulin in middle-aged men. Journal of Clinical and Endocrinological Metabolism, 79, 13 IO-I 3 16. Gianoulakis, C.. Krishnan, B. & Thavundayil, J. (1996). Enhanced sensitivity of pituitary beta endorphin to ethanol in subjects at high risk of alcoholism. Archives of General Psvchiafry, 53. 250-257. Gilbert. D. G. & Gilbert, B. 0. (1995). Personality, psychopathology, and nicotine response as mediators of the genetics of smoking. Behavior Genetics, 25, 133-147. Gilbert, D. G., Meliska. C. J., Welser. R. & Estes, S. L. (1994). Depression, personality, and gender influence EEG. cortisol, beta-endorphin, heart rate. and subjective responses to smoking multiple cigarettes. Personality and IndizlidualDcferences, 16.247-264.
Gilbert, D. G. & Welser, R. (1989). Emotion, anxiety and smoking. In T. Ney & A. Gale (Eds.). Smoking and human beharior (pp. 171-196). Chichester: Wiley. Guechot, J.. Lepine, J. P., Cohen, C.. Fiet, J., Lemperitre, T. & Dreux. C. (1987). Simple laboratory test of neuroendocrine disturbance in depression: 11pm saliva cortisol. Neuropsychobiology, 18, 14. Handa, K., Kono, S.. Ishii, H.. Shinchi, K., Imanishi, K. & Arakawa, K. (1994). Relationship of alcohol consumption and smoking to plasma cortisol and blood pressure. Journal qf Human H.vperlension, 8. 891-894. Inder. W. J.. Joyce, P. R.. Wells. J. E.. Evans, M. J.. Ellis, M. J., Mattioli, L. & Donald. R. A. (1995). The effects of alcoholism on the hypothalamic-pituitary-adrenal axis: interaction with endogenous opioid peptides. Clinical Endocrinological qf Oxford, 42.6557 I. Kiess, W., Meidert, R. A., Dressendbrfer, A. R., Schriever. K., Kessler, U., Konig, A., Schwarz, H. P. & Strasburger, C. J. (1995). Salivary cortisol levels throughout childhood and adolescence: relation with age. pubertal stage, and weight. Pediatric Research, 37. 502-506.
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Kirschbaum. C., Strasburger, C. J.. Jammers. W. & Hellhammer, D. H. (1989). Cortisol and behavior: I. Adaptation of a radioimmunoassay kit for reliable and inexpensive salivary cortisol determination. Pharmacology, Biochemistry & Behal)ior, 34, 747-15 1. Kirschbaum. C.. Wiist, S. & Hellhammer, D. H. (1992). Consistent sex differences in cortisol responses to psychological stress. Psychosomafic Medicine, 54, 648-657. Madianos, M. G.. Gefou-Madianou. D., Richardson, C. & Stefanis, C. N. (1995). Factors affecting illicit and licit drug use among adolescents and young adults in Greece. Acta Psvchiatrica Scandinaoica, 91, 258-264. Pauly. J. R.. Grun. E. U. & Collins, A. C. (1992). Glucocorticoid regulation of sensitivity to nicotine. In P. M. Lippiello, A. C. Collins &J. A. Gray (Eds.). The biology of nicotine: Current research issues (pp. 171-196). New York: Raven Press. Steven, C. S. & Nemeroff. C. F. (1994). Stress and psychiatric disorders. Seminars qfNeuroscience, 6, 271-280. Wall, T. L.. Nemeroff, C. B., Ritchie. J. C. & Ehlers, C. L. (1994). Cortisol responses following placebo and alcohol in Asians with different ALDHZ genotypes. Journal of Studies of Alcohol. 55. 207-213. Waltman, C., Blevins, L. S., Boyd, G. & Wand, G. S. (1993). The effects of mild ethanol intoxication on the hypothalamicpituitary-adrenal axis in nonalcoholic men. Journal of Clinical and Endocrinological Metabolism, 77, 518-522. Weidenfeld. J.. Bodoff. M., Saphier. D. & Brenner, T. (1989). Further studies on the stimulatory action of nicotine on adrenocortical function in the rat. Neuroendocrinology, 50. 132-138. Weinrich, S., Hardin. S., Valois. R. F., Gleaton, J., Weinrich. M. & Garrison, C. 2. (1996). Psychological correlates of adolescent smoking in response to stress. American Journal of Health Behattior, 20, 5240. Wing. J. K.. Babor. T.. Brugha, T.. Burke, J.. Copper, J. E., Giel. R.. Jablenski. A.. Regier, D. & Sartorius. N. (1990). SCAN: Schedules for Clinical Assessment in Neuropsychiatry. Archices of General Psvchiafr~. 47. 589-593. Wing, J. K.. Babor. T.. Brugha. T.. Burke. J.. Coooer. J. E.. Giel. R.. Jablenski. A.. Reeier. D. & Sartorius. N. (19931. I SCAN: Cuestionario para-la eraluaci& clinica en ‘Neuropsiquiatria. Madrid: Meditor. Yeaworth. R. C.. York, J.. Hussey, M. A., Ingle. M. E. & Goodwin, T. (1980). The development of adolescent life change event scale. Adolescence. XV, 91-98.
PII: so191-8sfi9(97)ooo93-7
INFLUENCE
Vol. 23, No. 4, pp. 593599, 1997
Q 1997Elsevier Science Ltd.
Pergamon
OF SMOKING AND DRINKING SALIVARY CORTISOL LEVELS
All rights reserved Printed in Great Britain 0191~8869/97 %17.00+0.00
HABITS ON
Josepa Canals,* M. Teresa Colomina, Jose L. Domingo and Edelmira Domenech Department of Psychology and Laboratory of Toxicology and Environmental Health, ‘Rovira i Virgili’ University, Tarragona, Spain, and Department of Health and Social Psychology, Autonomous University. Barcelona, Spain (Receioed 2 January 1997)
Summary-The present study assessed the association of smoking and drinking habits on salivary cortisol levels in a sample of 106 young teenagers. The gender, psychopathological disorders (ICD-10 criteria), and psychological stress variables were considered. Results showed that cortisol levels were significantly higher for moderate to heavy smokers (10 or more cigarettes per day) than for light and non-smokers. This effect was more remarkable in females than in males. Psychopathology was a factor influencing cortisol levels mainly in males. While high stress and elevated daily consumption of cigarettes were significantly associated with salivary cortisol levels. drinking habits did not influence these concentrations. 0 1997 Elsevier Science Ltd
INTRODUCTION
The relationship of the hypothalamic-pituitary-adrenal (HPA) axis with psychopathological disorders and other physiological and psychological factors has been widely investigated (Field, Colditz, Willett, Longcope & McKinlay, 1994; Kiess, Meidert, Dressendiirfer, Schriever, Kessler, Konig, Schwarz & Strasburger, 1995; Kirschbaum, Wtist & Hellhammer, 1992; Steven & Nemeroff, 1994). Tobacco consumption has been accepted as a factor influencing cortisol levels. In relation to it, while Field and co-workers (1994) reported that smoking is more important than other variables such as age, obesity, or dietary intake, Weidenfeld, Bodoff, Saphier and Brenner (1989) suggested that nicotine could be a potent stimulator of the adrenal system which acts through induction of corticotrophin releasing hormone (CRH) release after binding to cholinergic receptors in the hypothalamus. Although in general, data support that subjects smoking cigarettes have higher levels of cortisol than non-smokers (Eliasson, Hagg, Lundblad, Karlsson & Bucht, 1993; Field et al., 1994; Gilbert, Meliska, Welser & Estes, 1994), some investigators reported lower levels of cortisol in smokers than in non-smokers (Handa, Kono, Ishii, Shinchi, Imanishi & Arakawa, 1994). There are several reasons for these contradictory results. For example, psychopathology and smoking cigarettes are frequently associated. More specifically, major depression and anxiety disorders have been related to nicotine dependence (Breslau, 1995). This association is supported by the hypothesis of Gilbert & Welser (1989) and the results of Gilbert and associates (1994) showing that nicotine has antidepressant effects. So depressed smokers would have smaller responses to nicotine than nondepressed smokers. In this sense, while psychopathology could increase adrenal hormone levels, the high cortisol levels in smokers might reduce the behavioral effects of nicotine as well as the binding of nicotine and neurotransmitters to CNS receptors (Pauly, Grun & Collins, 1992). Other variables that could also explain different cortisol levels between smokers and non-smokers are gender, degree of habitual nicotine exposure or tolerance, dose of nicotine, personality traits or stress (Gilbert et al., 1994; Gilbert & Gilbert, 1995). Alcohol consumption has also been studied as a stimulator of the HPA axis. While some investigators (Adinoff, Risher-Flowers, De-Jong, Ravitz, Bone, Nutt, Roehrich, Martin & Linnoila, 1991) suggested that there is a marked increase of the cortisol levels associated with the alcohol withdrawal, other authors did not find similar results. A positive association between alcohol intake and cortisol was recently reported in randomly sampled middle-aged US men (Field et al., 1994).
*To whom all correspondence should be addressed. 593
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Ekman, Vakkuri, Vuolteenaho and Leppaluoto (1994) also found higher levels of cortisol in plasma of subjects who received high doses of ethanol than in individuals given placebo. However, other investigators did not find any activation of the HPA axis in individuals given ethanol at doses that caused acute intoxication (Inder, Joyce, Wells, Evans, Ellis, Mattioli & Donald, 1995; Waltman, Blevins, Boyd & Wand, 1993), in subjects receiving lower concentrations of alcohol (Gianoulakis, Krishnan & Thavundayil, 1996) or in subjects with chronic alcoholism (Del Arbol, Aguirre, Raya, Rico, Ruiz-Requena & Miranda, 1995). It is possible that the reaction to alcohol and the cortisol response to this drug are due to individual differences. Chronic alcohol consumption could be related to chronic stress, which could also modify cortisol levels. Wall, Nemeroff, Ritchie and Ehlers (1994) showed significant higher blood cortisol levels in subjects with a genotype related to alcoholinduced flushing than in those with a different genotype. As for smoking habits, depression and minor mental disorders have been also associated with alcohol consumption (Deykin, Levy & Wells, 1986; Madianos, Gefou-Madianou, Richardson & Stefanis, 1995). Thus, psychopathology could modify adrenal hormone levels and reduce the effects of alcohol. Salivary cortisol reflects the fraction of plasma cortisol not bound to proteins. It is a more sensitive indicator of adrenal function than total plasma cortisol (Gutchot, Lepine, Cohen, Fiet, Lemperiere & Dreux, 1987). Moreover, this parameter offers advantages such as non-stressing sampling, the fact that individuals can provide samples by themselves, and that salivary cortisol levels are not modified by estrogens (oral contraceptives) (Kirschbaum & Hellhammer, 1989). To date, no data on the effects of smoking and drinking habits (considering simultaneously gender and psychopathological variables) on salivary cortisol concentrations in the general population have been reported. In the present study we assessed the effects of smoking and drinking habits on salivary cortisol levels in a sample of teenagers. The influence of gender, psychopathological disorders, and psychological stress as possible interacting factors on the salivary cortisol concentrations was also evaluated.
METHOD Subjects
The Ss were young teenagers (17.5-18.5 yr) of a general population living in Reus (Catalonia, Spain) who had participated in a longitudinal study of development and psychopathology since the age of 10-l 1 yr. Although at the beginning of the study 579 children (334 boys and 245 girls) agreed to be included in the study, only 304 could be recruited at the age of 18 yr. Of these, 134 (62 males and 72 females) returned the salivary samples, but cortisol levels were finally evaluated in 106 individuals owing to problems with the sample collection. All participants were called at educational centers and examined. Absent individuals were subsequently recruited by phone or letter. All Ss were singles and living with their families. Smoking and drinking assessment
A self-report questionnaire was elaborated for this research. This questionnaire asked for smoking and/or drinking habits, the age at which they started smoking and drinking, and the kind and amount of alcoholic beverages. Additional information from Schedules for Clinical Assessment in Neuropyschiatry (SCAN, Spanish version) (Wing, Babor, Brugha, Burke, Copper, Giel, Jablenski, Regier & Sartorius, 1990; Wing, Babor, Brugha, Burke, Copper, Giel, Jablenski, Regier & Sartorius, 1993) about how much the Ss smoked and drank, as well as tobacco dependence (wish of smoking cigarettes) was also used. Individuals were divided into three groups according to the number of cigarettes smoked daily: non-smokers (no cigarettes), light smokers (one to nine cigarettes), and moderate to heavy smokers (ten or more cigarettes). In relation to the variable dependence to tobacco, Ss were also distributed into three categories: non-dependence (those who answered ‘no need’), low dependence (‘some controllable need’) and high dependence (‘strongneed and it is difficult to live without tobacco’). To evaluate alcohol consumption Ss were divided into non-drinkers (those who drank never or just ocasionally) and drinkers (those who drank daily or during the weekend). At the age of assessment almost all Ss drank during the weekends.
Salivary cortisol levels
595
Measurement of stressful life events
To collect information on stressful life events during the preceding year, an experimental ‘Adolescent Life Change Event Scale’ (ALCES) form (Yeaworth, York, Hussey, Ingle & Goodwin, 1980) was used. Life change events refer to a number of personal, social, familiar and occupational life changes, which presumably could create stress. The first step includes 31 items on a rating scale from 1 (‘not at all upset’) to 5 (‘extremely upset’). To ascertain if the subject had experienced the event, on the second step of the questionnaire the items were repeated without rating scales. Total stress affecting an individual was calculated by adding all events experienced (second step of the questionnaire) multiplied by the subjective score assigned to each item (first step). Stress levels were designated ‘low’ or ‘high’ when the score was lower or higher than 25, respectively. Psychopathology assessment
Psychiatric diagnoses were made with the Schedules for Clinical Assessment in Neuropsychiatry (SCAN, Spanish version) (Wing et al., 1990, 1993) and based on the ICD-10 criteria. The most frequent diagnoses found were sleep disorders, mood disorders and anxiety disorders (Canals, Domenech, Carbajo & Blade, in press). Diagnoses were generated by a computerized version of SCAN. Based on preliminary results (unpublished data), two groups (total sample and sample without psychopathology) were defined to evaluate the relationship between smoking and drinking habits and cortisol. Cortisol analysis
Salivary samples were collected between 07:OOand 09:OOhr. Each S was asked to collect approximately 2ml of saliva with a syringe and to keep that volume in a polypropylene tube at room temperature for 24 hr. Subsequently, the samples were stored at - 20°C until analysis. Samples were centrifuged at 3000 xg for 5 min to remove mucins and any cellular debris. Salivary cortisol concentrations were determined using the ‘Magic Cortisol’ radioimmunoassay kit (Ciba-Corning, Gieben, Germany) as modified by Kirschbaum, Strasburger, Jammers and Hellhammer (1989) with a sensitivity of 0.1 pg/dl. Each sample was measured in duplicate and averaged. Statistical analysis
Statistical analyses were carried out with the SPSS software package. One-way analysis of variance (ANOVA) was used. Multiple comparisons between groups were conducted with the LSD (least significant difference) test. A correlational method was also used to assess the association between two variables. Differences were considered to be significant at P < 0.05. RESULTS Although the smoking population (n = 42) showed higher cortisol levels (0.569 + 0.25 pg/dl) than the non-smoking population (n = 64) (0.496 + 0.34 pg/dl), the differences between these groups were not statistically significant. In males, salivary cortisol levels were 0.602 +0.23 pg/dl for smokers (n = 22) and 0.523 + 0.42 pg/dl for non-smokers. In turn, although males showed higher salivary cortisol levels than females, the differences between sexes did not reach the level of statistical significance. Table 1 shows the mean salivary cortisol levels for all the Ss according to the daily consumption of cigarettes. Moderate to heavy smoker females showed higher cortisol levels than non-smokers or light smokers, but in males the increases were not statistically significant. However, when Ss with mental disorders were excluded, salivary cortisol levels in males were found to be significantly increased in moderate to heavy smokers as against non-smokers. The correlations between the daily consumption of cigarettes and the salivary cortisol concentrations are presented in Table 2. A higher correlation was found for Ss without psychopathology than for individuals in the total sample. The highest correlation was observed in males without disorders, although the level of statistical significance was only reached for the total population (males and females).
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Table 1. Mean (SD) salivary cortisol levels (pg/dl) according to the daily consumption of cigarettes Males Mean (SD)
Females n
Mean (SD)
All subjects n
Mean
n
Total sample
Non-smokers
0.523’ (0.42)
28
Light smokers
0.570’ (0.31)
Moderate to heavy smokers
0.476” (0.28)
36
0.496’ (0.35)
64
7
0.430 (0.27)
13
0.480 (0.28)
20
0.617” (0.19)
15
0.723b (0.19)
7
0.65W (0.19)
22
Non-smokers
0.396” (0.27)
18
0.448’ (0.26)
24
0.425’ (0.26)
42
Light smokers
0.570”b (0.31)
7
0.482” (0.31)
7
0.52Vb (0.30)
14
Moderate to heavy smokers
0.606b (0.21)
12
0.717” (0.24)
4
0.634” (0.21)
16
Sample without psychopotho1og.v
For each sex, results in the total sample or in the sample without psychopathology not showing a common superscript are significantly different from each other at PcO.05. No differences between sexes were found.
Table 2. Correlation between the daily consumption of cigarettes and salivary cortisol levels Males
P
Females
P
Total
P
Total sample
0.137 II=53
NS
0.220 n=56
NS
0.170 !I= 109
NS
Sample without pathology
0.345 n=37
NS
0.294 n=35
NS
0.285 n=72
<0.05
NS, not statistically significant, P~0.05.
Table 3. Mean (SD) salivary cortisol levels (pg/dl) and smoking dependence Males Mean (SD) Total sample No dependence
Females ”
Mean (SD)
Total n
Mean (SD)
n
0.522” (0.38)
37
0.491’ (0.28)
49
0.504’ (0.32)
86
Low dependence
0.598” (0.17)
7
0.483” (0.320)
6
0.545” (0.25)
13
High dependence
0.727” (0.19)
6
0.870
I
0.747b (0.23)
7
0.438 (0.27)
27
0.484 (0.28)
32
0.463” (0.27)
59
Low dependence
0.598” (0.17)
7
3
0.570” (0.23)
10
High dependence
0.793b (0.26)
3
0.503” (0.36) _
0
0.793b (0.26)
3
Sample without psychopathology No dependence
For each sex, results in the total sample or in the sample without psychopathology not showing a common superscript are significantly different from each other at P~0.05. No differences between sexes were found.
The salivary cortisol levels classified according to cigarette-smoking need are shown in Table 3. Although cortisol concentrations were increased in both males and females with high dependence, significant differences were only observed in males without psychopathology or in the total sample. Table 4 summarizes the salivary cortisol concentrations according to smoking habits and levels of stress. Females classified as moderate to heavy smokers showed non-significantly higher cortisol levels than the non-smokers or light smokers, with the increases being more evident for high stress individuals. In males, although moderate to heavy smokers with high stress showed increased salivary cortisol levels compared with those with low stress, the differences did not reach the level of statistical significance.
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597
Table 4. Mean (SD) salivary cortisol levels (pg/dl) according to the number of cigarettes and stress levels Females
Males n
Mean (SD) Low
Total n
Mean (SD)
Mean (SD)
n
stress
Non-smokers
0.547 (0.46)
0.385” (0.23)
16
0.490 (0.39)
37
Light smokers
0.570” (0.31)
7
0.375 (0.21)
4
0.499’ (0.29)
II
Moderate to heavy smokers
0.559’ (0.11)
12
0.653” (0.25)
3
0.578’ (0.14)
15
Non-smokers
OSOl” (0.31)
9
0.534” (0.21)
18
0.51 I” (0.23)
25
Light smokers
0.453” (0.28)
7
0.458” (0.30)
9
0.457” (0.30)
9
Moderate to heavy smokers
0.670” (0.07)
2
0.775” (0.15)
4
0.74Ob (0.13)
6
21
High stress
For each sex, results in the total sample or in the sample without psychopathology not showing a common superscript are significantly different from each other at PiO.05. No differences between sexes were found.
Table 5. Salivary cortisol levels (pg/dl) and alcohol consumption Males Mean
Females n
Mean
Total n
Mean (SD)
n
Total sample
Nondrinkers
0.529” (0.33)
27
0.480” (0.27)
21
0.500” (0.29)
68
Drinkers
0.560” (0.35)
23
0.510’ (0.30)
14
0.560 (0.34)
37
Sample without psychopathology Non-drinkers 0.495” (0.29)
21
0.449” (0.25)
22
0.470 (0.27)
47
Drinkers
16
0.590 (0.34)
9
0.532 (0.29)
25
0.499 (0.26)
For each sex, results in the total sample or in the sample without psychopathology not showing a common superscript are significantly different from each other at PcO.05. No differences between sexes were found.
Table 5 shows the salivary cortisol levels for all Ss in relation to alcohol consumption. Although no significant differences between drinkers and non-drinkers could be seen, an increase in salivary cortisol levels was observed in the group of drinker females without psychopathology. DISCUSSION As previously reported (Eliasson et al., 1993; Field et al., 1994) smokers showed higher cortisol levels than non-smokers. When Ss were classified only as smokers and non-smokers, salivary cortisol levels were higher in males than in females. These increases were similar to those observed in the group of non-smokers classified according to sex. However, an important increase of cortisol levels for moderate to heavy smoker females was observed when Ss were distributed according to the number of cigarettes smoked. Salivary cortisol levels were significantly higher in moderate to heavy than in light and non-smoker females, whereas higher cortisol concentrations were also found in moderate to heavy smoker females than in males, These data suggest that the effects of high doses of nicotine on salivary cortisol levels are more evident in females than in males. Smoking habits in males significantly increased cortisol levels only when Ss affected by psychopathology were excluded. This finding shows that psychopathology can be a factor influencing cortisol levels mainly in males, which would be in agreement with the results of previous investigations (unpublished data). In this sense, the correlation between salivary cortisol concentrations
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Josepa Canals et al.
and the daily consumption of cigarettes was higher in males when psychopathology was excluded. A significant positive correlation for the sample without psychopathology was also found. Although a high dependence on tobacco was associated with higher salivary cortisol levels in males and females, only one woman could be included within the high dependence group. As seen for the daily consumption of cigarettes, cortisol levels were significantly higher for males with a high dependence when mental disorders were excluded. Moreover, Ss in that group were also moderate to heavy smokers. When the sample was divided according to the stress variable, both smoking habits and high stress influenced the salivary cortisol levels in males and females. The increase on salivary cortisol levels indicating a great stress response would support a synergistic effect between stress and tobacco as risk factors in some diseases (e.g. ischaemic diseases). In this sense, Eysenck (1988) reported that smoking affects health negatively only in conjunction with other factors like personality. In relation to sex, although higher cortisol levels in females than in males could be observed as a trend in response to tobacco or high stress, the differences did not reach the level of statistical significance. In turn, higher cortisol concentrations were also observed in moderate to heavy smoker females with low stress. These results would support previous findings about differences between males and females, with psychopathology or with high stress, on salivary cortisol levels (Canals, Colornina, Gallart & Domingo, 1997). In females, cortisol levels seem to be more influenced by external factors (stress, tobacco), while internal factors (psychopathology) would be more relevant in males. As reported by Weinrich, Hardin, Valois, Gleaton, Weinrich and Garrison (1996), the activity of the HPA axis increases in response to stress either alone or interacting with personality and social factors. This fact could contribute to the onset and maintenance of smoking habits among some adolescents. Although the results for alcohol consumption are consistent with data of previous reports (Del Arbol et al., 1995; Gianoulakis et al., 1996), the comparison of the present results with data from other authors should be carefully performed. It should be taken into account that the sample used in the current study concerned a young population (18 yr), whereas in addition almost all the individuals in the group of drinkers consumed alcohol only during the weekend. Moreover, the period of time elapsed between the salivary cortisol sampling and the last alcohol consumption was unknown. On the other hand, the increased cortisol levels in drinker females could be due to a dependent alcohol-stress factor. Consequently, further studies should be carried out in order to corroborate gender differences in response to nicotine, stress and psychopathological disorders and their relationship as risk factors. Acknowledgement-This research was supported by a grant from the ‘Fond0 de Investigation Sanitaria’ (FIS 94/0866). Ministerio de Sanidad y Consumo, Spain.
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