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Mental health indicators and their association with smoking in Guadalajara teenagers by sex

How to cite this article: Nuño-Gutiérrez BL, Celis-De la Rosa A, García-Pérez OP. Mental health indicators and their association with smoking in Guadalajara teenagers by sex. Rev Med Inst Mex Seguro Soc. 2015;53(5):570-7.

PubMed: http://www.ncbi.nlm.nih.gov/pubmed/26383806


ORIGINAL CONTRIBUTIONS

Received: June 6th 2014

Accepted: June 2th 2015


Mental health indicators and their association with smoking in Guadalajara teenagers by sex


Bertha Lidia Nuño-Gutiérrez,a Alfredo Celis-de la Rosa,b Olga Patricia García-Pérezc


aUnidad de Investigación Epidemiológica y en Servicios de Salud del Adolescente (UIESSA). Instituto Mexicano del Seguro Social. Delegación Jalisco/ Universidad de Guadalajara.

bUnidad de Investigación Clínica. Instituto Mexicano del Seguro Social. Delegación Jalisco/ Universidad de Guadalajara.

cUnidad de Investigación Epidemiológica y en Servicios de Salud del Adolescente (UIESSA). Instituto Mexicano del Seguro Social. Delegación Jalisco


Communication with: Bertha L. Nuño-Gutiérrez

Telephone: (0133) 33 3683 2970

Email: bertha.nuno@imss.gob.mx


Background: To associated mental health factors with tobacco-smoking in the last month in scholastic adolescents.

Methods: An analytic transversal study with 1134 students in the first year of senior studies in a government preparatory school. Ten mental health factors were evaluated: self-esteem, impulsiveness, depressive symptoms, suicide ideation, disordered eating, recreation, locus of control, relationship with father, relationship with mother and stress.

Results: We found mental health factors differences between men and women. In the risk analysis, the factors which associated with tobacco smoking in men were high self-esteem, impulsiveness, age and tobacco-smoking in friends. For the women suicide ideation, impulsiveness disordered eating, age and tobacco-smoking in friends and brothers. After the logistic regression were associated impulsiveness and tobacco-smoking in friends for both, high self-esteem and age for men, and tobacco-smoking in brothers for women.

Conclusions: Mental health factors are different for men and women. However, all of them are a reference that tobacco-smoking is associated with the inner world of teens that are meaning differently for men and women.

Keywords: Adolescent, Mental health, Smoking.


Smoking is a public health problem; it is estimated that nearly six million people die each year worldwide from diseases attributed to tobacco, which is equivalent to one death every six seconds.1 Although tobacco consumption has remained stable in the last four years, and although attending school is a protective factor for drug use, smoking prevalence in Mexican high school students (40%) is higher when compared to smoking in the general adolescent population (12.3%). As for the consumption differential between men and women, there has been an increase in female active smokers from 2002 (3.8%) to 2011 (8.1%) in the 13-15 age group.2

Some factors identified that directly affect smoking among adolescents in school include: working in addition to studying,3 attending classes in the afternoon schedule,3 smoking in family,4-8 low perception of risk, favorable attitudes toward tobacco,9 dismissing the possibility of becoming a smoker, social tolerance, high availability and access to cigarettes, poor school performance,3 weight control, reaffirming the passage to adulthood,16 little monitoring from parents,12 curiosity,13 and parents with tendency to aggressive behavior and attempted sexual abuse.15

Depressive symptoms, hostility, and anxiety are related to the intensity of smoking, which increases the risk of dependency.16 Although some sociodemographic, family, and social environment characteristics associated with smoking among adolescents have been identified, the role of mental health has been little explored and, so far, has not been evaluated: impulsivity, self-esteem, locus of control, suicidal ideation, recreation and disordered eating (DE) could guide the design of preventive strategies incorporating psychological elements; because of this, the objective of this study was to evaluate the strength of association between mental health indicators and current smoking among adolescents in school.

Methods

A cross-sectional study in 2011 that included all pupils in first and second semester of a public high school of the Universidad de Guadalajara (Preparatoria Número 5) in both morning and afternoon schedules was performed. 93% of students listed were located and agreed to participate. The remaining 7% could not be reached because some students had dropped out or changed schools.

For data collection a self-administered, anonymous survey of 159 questions was applied, within the school schedule and venue, lasting about 30 minutes. The questionnaire included three sections:

 

  • Consumption of tobacco in the past 30 days,17 which was the outcome variable;
  • Mental health indicators evaluated by standardized and validated scales in Mexican adolescents in middle and high school, which were classified as: 1) daily stress in the last three months,18 2) locus of control of luck,19 affectivity,20 and internality,21 3) self-esteem,21 4) impulsivity,22 5) depressive symptoms in the last week,23 6) suicidal ideation ever in life,24 7) recreation in last two weeks,17 8) relationship with father,22 9) relationship with mother,22 and 10) disordered eating (DE) in the last three months;25
  • Sociodemographic and school data (age, sex, semester, schedule, school calendar, average school performance immediately preceding, type of student [regular / irregular], working in addition to studying, and tobacco consumption in family and friends).

 

The questionnaires used Likert scales to indicate how often they experienced each situation. The scales of relationship with father / mother, impulsivity and DE had four choices: never / rarely, sometimes, often (twice / week) and very often (more than twice / week). Self-esteem and locus of control statements to indicate how much they agree were: strongly disagree, disagree, agree and strongly agree. Daily stress was identified as experiencing discomfort in common situations: none, little, some and a lot. Depressive and recreation symptoms were assessed describing the frequency of events that took place. Suicidal ideation assessed the experience of self-injurious thoughts.

For statistical analysis the sample was divided by sex and for each sex, mean and standard deviation for each evaluated indicator was calculated. For each group the presence of smoking in the last 30 days was identified. Subsequently, the independent variables were dichotomized to estimate the risk of smoking estimating crude odds ratios using 2x2 contingency tables and adjusted using logistic regression. To define the multivariate model all independent variables that showed an association with significance p ≤ 0.25 were included, but the final model included only those that showed a level of p ≤ 0.05. Confidence intervals were calculated at 95%. Statistical analysis was performed using SPSS for Windows version 15.

According to the Ley General de Salud,26 the study was considered without risk, since it did not include the intentional modification of variables. The project was approved by the Research Ethics Committee of the Instituto Mexicano del Seguro Social, it was also approved by the host school. Informed consent was requested by writing from participants and confidentiality of information was assured. Psychotherapeutic care service at school was used to address cases that might arise. Two students sought care for illegal drug use and one more for depressive symptoms. The cases were treated and permission requested from students to talk to their parents and involve them, since it was necessary to refer them to specialized care.

Results

1134 high school students of first and second semester were surveyed, none of them refused to answer the questionnaire. Of the total, 463 (40.8%) were men and 671 (59.2%) were women. The average age of both groups was 15.1 with a standard deviation of 2.2 years, a minimum age of 15 and maximum of 19. We found a current smoking prevalence of 10.4%, with no significant difference between men (11.4%) and women (9.7%).

When comparing the proportion of smokers by sex, except for 16-year-old men, the proportion of women was higher. The highest proportion of smokers was concentrated in the second semester. With regard to school variables, we note that the afternoon schedule concentrated the highest proportion of smokers, school performance average was lower in smokers, and irregular students were smoking in greatest proportion. History of smoking in friends and relatives was proportionally greater in smokers (Table I).


Table I Demographics of adolescents by smoking
Characteristics Men Women
With smoking
n= 53 (%)
Without smoking
n= 410 (%)
With smoking
n= 65 (%)
Without smoking
n= 606 (%)
Age
15 years 18(34.0) 248(60.5) 34(52.3) 400(66.0)
16 years 26(49.0) 125(30.5) 23(35.4) 173(28.3)
17 years and older 9(17.0) 31(7.6) 7(10.8) 18(3.0)
No data 0(-) 6(1.5) 1(1.5) 15(2.5)
Semester
1 24(45.3) 144(35.0) 26(40.0) 195(32.2)
2 29(54.7) 262(64.0) 37(57.0) 406(67.0)
3 4(1.0) 2(3.0) 5(0.8)
School schedule
Morning 16(30.2) 235(57.3) 29(44.6) 338(55.8)
Evening 37(69.8) 175(42.7) 36(55.4) 267(44.1)
Type of student
Regular 46(86.8) 371(90.5) 60(92.3) 558(92.1)
Irregular 5(15.2) 28(6.8) 5(7.7) 36(5.9)
No data 2(3.8) 11(2.7)
Smoking in friends
Yes 41(77.4) 234(57.1) 56(86.2) 309(51.0)
No 12(22.6) 176(42.9) 9(13.8) 297(49.0)
Smoking in father
Yes 16(30.2) 105(25.6) 20(30.8) 167(27.6)
No 37(69.8) 305(74.4) 45(69.2) 439(72.4)
Smoking in mother
Yes 15(28.3) 73(17.8) 17(26.2) 111(18.3)
No 38(71.7) 337(82.2) 48(73.8) 495(81.7)
Smoking in siblings
Yes 14(26.4) 67(16.3) 23(35.4) 107(17.7)
No 39(73.6) 343(83.7) 42(64.6) 499(82.3)
School performance average 71.3(SD 26.4) 75.4(SD 27.1) 67.1(SD 34.2) 75.5(SD 29.9)

On the whole, in the bivariate analysis, current smoking was associated with: the presence of stress, suicidal ideation, impulsivity, DE, age, and smoking in friends, mother, and siblings. After analysis adjusted for logistic regression, statistically significant association for the whole was retained only for suicidal ideation, impulsivity, age, smoking friends, and smoking parents (Table II).

The bivariate analysis found no significant differences in mental health indicators associated with smoking by gender; in men high self-esteem, high impulsivity, age (16-17 years) and smoking in friends. In women suicidal ideation, high impulsivity, DE, age (17 years), smoking in friends and smoking in siblings.


Table II association between mental health indicators and current smoking in adolescents
Mental health indicators Smoking Bivariate analysis Multivariate analysis
Yes
(n(= 118)
No
(n(= 1016)
ORr 95% CI ORa * 95% CI
Self-esteem 21 153 1.2 0.7 2.0
Depressive symptoms 22 149 1.3 0.9 2.9
Psychosocial stress 26 146 1.7 1.0 2.7
Suicidal ideation 24 110 2.1 1.3 3.4 1.7 1.0 2.9
Impulsivity 40 121 3.8 2.5 5.8 3.2 2.0 5.1
Internal locus of control 10 140 0.6 0.2 1.1
Recreation 20 133 1.4 0.8 2.3
Bad relationship with mother 15 128 1.0 0.6 1.8
Bad relationship with father 14 160 0.7 0.4 1.3
Disordered eating behaviors 14 68 1.9 1.0 3.4
Sex
Male 53 410 1.2 0.8 1.8
Age:
16 years 49 298 2.0 1.3 3.2 1.9 1.2 2.9
17 years 16 49 4.1 2.2 8.0 3.4 2.1 5.7
Smoking in friends 97 543 4.0 2.5 6.6 3.4 2.1 5.7
Smoking in mother 32 184 1.7 1.1 2.6
Smoking in father 36 272 1.2 0.8 1.8
Smoking in siblings 37 174 2.2 1.4 3.4 2.0 1.3 3.2
ORc = Odds ratio raw
Or = Odds ratio adjusted
* OR adjusted by the two variables together

After multivariate analysis, association in men was identified with: self-esteem, impulsivity, age (16-17 years) and smoking in friends. In women association was retained with: impulsivity, smoking in friends and smoking in siblings (Table III).


Table III Association between mental health indicators in adolescents and smoking by sex
Mental health indicators Men Women
Univariate Association Multivariate Association * Univariate Association Multivariate Association
ORr 95% CI ORa 95% CI ORr 95% CI ORa 95% CI
Self-esteem -2.0 1.0 3.9 -2.3 -1.1, - 4.8 -0.8 0.3 1.6
Depressive symptoms -1.1 0.5 2.6 -1.5 0.8 2.8
Stress -1.8 0.9 3.7 -1.6 0.8 3.0
Suicidal ideation -1.4 0.7 3.1 -2.8 1.5 5.3
Impulsivity -3.0 1.5 5.5 -2.8 -1.4, - 5.4 -4.6 2.6 8.2 4.4 2.4 8.1
Locus of control -0.5 0.2 1.3 -0.6 0.2 1.6
Recreation -1.2 0.6 2.7 -1.4 0.7 2.8
Bad relationship with mother -0.9 0.4 2.0 -1.1 0.5 2.4
Bad relationship with father -0.9 0.4 2.0 -0.6 0.3 1.4
Disordered eating behaviors -1.4 0.3 6.6 -2.2 1.1 4.3
Age:
16 years -4.6 2.5 8.8 -2.7 -1.4 - 5.3 -1.6 0.9 2.8
17 years -4.0 1.5-10.4 -4.2 -1.7 - 10.6 -4.6 1.6-12.7
Smoking in friends -2.6 1.3 5.0 -2.3 1.2 4.7 -6.0 2.9-12.3 5.3 2.6-11.1
Smoking in mother -1.8 0.9 3.5 -1.6 0.9 2.8
Smoking in father -1.2 0.7 2.4 -1.2 0.7 2.0
Smoking in siblings -1.8 0.9 3.4 -2.0 1.5 4.4 2.7 1.5 4.8
ORr = Odds ratio raw
ORa = Odds ratio adjusted
* OR adjusted by the variables in the model together

Discussion

The study identified that, for the whole set, the associated mental health indicators independent of current smoking were: suicidal ideation, impulsivity, smoking in friends / parents and being 16 or 17 years old. For men, independently associated factors were: self-esteem, impulsivity, smoking in friends and age 16-17, and for women: impulsivity and smoking in friends / siblings. While these indicators were different in the two groups, we suggest that they indicate that smoking is associated with the inner world of teenagers. Peer influence is an internal reference, because it represents patterns of behavior desired by oneself, but construed differently by men and women.

Interestingly, multivariate analysis showed significant association for the whole group with suicidal ideation and smoking in parents, but this significance was lost in the cluster analysis. Some studies have linked smoking to suicidal ideation,27 representing emotional distress and a condition of greater psycho-affective vulnerability as well as the influence of family smoking on adolescent smoking.4 

It was not surprising that high self-esteem is associated with smoking in men, because self-esteem decreases in depressive states in which the individual is neglected and devalues themself,28 while it increases in euphoric states. In this respect, self-esteem seems to reinforce the feeling of invulnerability in men, perhaps because they gain confidence as they move toward the final stage of adolescence.

Impulsivity and peer smoking were the mental health indicators that were present in men and women. Impulsiveness is a cognitive style in which subjects tend to have risky behaviors that endanger their own and / or others’ wellbeing and which they do without taking into account the consequences.29 Impulsivity covers a wide range of actions that are poorly conceived, expressed prematurely, excessively risky or with inappropriate responses, and often with undesirable results.30 Impulsiveness has been associated with behavioral problems, aggression, peer relationship problems, antisocial behavior, and attention deficit disorder.30 Smoking in peers (friends / siblings) has been cited as an important factor of social influence on adolescent smoking.3,10 In this case, we suggest that <impulsivity and peer smoking> form a relationship that favors intragroup smoking because the group's actions embodied in smoking are observed, admired and coveted by teenagers, whose identity is under construction and in search of affirmation, so that smoking is quickly accepted. Otherwise, they would not be highly influential figures. Although age is not really an indicator of mental health, we suggest that it appeared in the multivariate model as an indicator of middle adolescence, in which different identities are tested. It has been reported3,14 that teenagers experiment with tobacco before age 15. The Encuesta Nacional de Adicciones 2011 estimated on average 14.1 years, with no difference between men and women, and found that age of onset has remained stable from 2002 to 2011. This means that a proportion of adolescents start high school consuming tobacco and continue consumption through 16-17 years of age, which could also mean that progress through high school increases the risk of consumption and continued use, which translates into a niche opportunity for secondary prevention.

Although smoking prevalence was not statistically different between men and women, women are a group that should be given special attention, from the point of view of prevention. When comparing the prevalence in the last decade (2002-2011) an increase of four percentage points of current female smokers (3.8% vs. 8.1%) was observed, especially in the of 13-15 age group.2

Smoking has different dynamics between men and women.9 Women have historically been defined by their reproductive function, generating exclusion in activities that were progressively more socially valued, and so, the division of labor outlined conditions of inequity and inequality. As such, gender is a social construct that cannot be explained solely by its effects. The power of history and the force of tradition prevails in the constitution of these differences, even though the meanings change and new behaviors allow the emergence of new meanings in these constructions. From this historical perspective of femininity, drug use is opposed. However, it seems that the incursion of women into areas that were unique to the male role has relaxed its historic role and changed the attitude towards their traditional role, at least in women. As such it seems that a new female model is being rebuilt, which appears ready to replace traditional inequity and inequality, where smoking appears to be an active instrument that redefines an image of power and glamor. We therefore propose that the gender system appears to mediate indicators of adolescent smoking, so this dynamic requires greater depth in future studies under qualitative designs, to incorporate a strong cultural component in the design of anti-smoking educational interventions based on scientific evidence.

As for school-related variables we note that the afternoon schedule (higher dropout rate) concentrated a higher proportion of smokers as well as a lower school performance average and higher proportion of irregular students, suggesting that smoking affects academic trajectory.3

It is not possible to indicate the directionality of the variables studied by the cross-sectional design of the study, which would be studied by longitudinal and case-control designs. Additionally, although the sample comes from a typical school in the metropolitan area of ​​Guadalajara, the data do not represent the entire school system, making it possible to find differences in the mental health-smoking relationship in suburban or rural settings.

Despite these limitations, the study allows us to suggest that prevention must include elements of the inner world of the teenager, which appear to impact smoking significantly. Prevention should include both the intrapersonal (the relationship with the self, represented by self-esteem, impulsivity) and the interpersonal (the relationship with the other represented by the influence of smoking in peers / siblings). From the psychotherapeutic point of view, impulsivity requires work individually and in small groups with cognitive-behavioral techniques and / or clinical hypnosis to modify self-identity, training in self-relaxation, slowing responses, modeling behavior and training in assertiveness skills for proactive coping. In addition, for men it would be appropriate to work to control euphoria (represented by high self-esteem) towards an internal focus, greater introspection, as well as training in assertiveness skills to resist peer pressure.

Teen smoking is a priority issue because it represents the prelude to the installation of smoking and the last chance to intervene before they become dependent on nicotine and require other more complex, more costly interventions outside the influence of community settings.


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Conflict of interest statement: The authors have completed and submitted the form translated into Spanish for the declaration of potential conflicts of interest of the International Committee of Medical Journal Editors, and none were reported in relation to this article.

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