Authors:
Do Eun Park1, Seong-Kyung Cho2 and Jaelim Cho3*
Affiliation(s):
1Korean Minjok Leadership Academy, Anheung-myeon, Hoengseong-gun, Gangwon-do, Republic of Korea
2Department of Medical Informatics and Biostatistics, Yonsei University College of Medicine, Seoul, Republic of Korea
3Department of Occupational and Environmental Medicine, Gachon University Gil Medical Center, Incheon, Republic of Korea
Dates:
Received: 18 April, 2016; Accepted: 21 May, 2016; Published: 23 May, 2016
*Corresponding author:
Jaelim Cho, MD, MPH, Department of Occupational and Environmental Medicine, Gachon University Gil Medical Center, 774 Namdongdae-ro, Incheon, Republic of Korea, Tel: +82-32-820-2240; Fax: +82-32-814-9014; E-mail: @
Citation:
Park DE, Cho SK, Cho J (2016) Association between Perceived Stress and Asthma Symptoms in Adolescents. Arch Community Med Public Health 2(1): 011-014. DOI: 10.17352/2455-5479.000009
Copyright:
© 2016 Park DE, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Background: Although the effect of psychological stress on asthma has long been suggested, there is little evidence regarding asthma symptoms such as wheezing in relation to perceived stress in adolescents.

Objectives: We investigated the relationship between perceived stress and asthma symptoms in a nationally representative sample of Korean adolescents.

Methods: We used the data from the eighth Korean Youth Risk Behavior web-based Survey (KYRBS), which is based on a self-reported questionnaire. Perceived stress was classified into five ratings from very high to very low. Asthma symptoms included wheezing and wheezing on exertion during the last 12 months. We performed multiple logistic regression analysis, adjusting for grade (age), sex, asthma history, drinking experience, smoking experience, exposure to secondhand smoke, physical activity, fast food consumption, snack consumption, subjective health status, body mass index category, and household economic status.

Results: Of 72,229 participants, 8,224 (11.4%) and 14,658 (20.3%) adolescents reported experiencing wheezing and wheezing on exertion, respectively, during the last 12 months. Participants who reported very high stress had higher odds of wheezing (Odds ratio, 2.621; 95% confidence interval, 2.040–3.367) and wheezing on exertion (1.960; 1.638–2.344) in reference to those with very low stress. With the increase in subjective stress ratings, ORs of wheezing and wheezing on exertion had a rising trend, and the trends were statistically significant (p<0.001 for wheezing and p<0.001 for wheezing on exertion).

Conclusions: Perceived stress was positively associated with wheezing and wheezing on exertion in Korean adolescents, both in asthmatics and non-asthmatics.

Introduction

Asthma is a prevalent allergic disease worldwide, affecting approximately 334 million people, and 14% of children suffer asthma symptoms globally [1]. Reported risk factors for asthma include secondhand smoke [2], traffic-related air pollution [3], trans fatty acids intake [4], obesity [5], infection [6], and pollens [7]. Through interacting with these environmental risk factors, stressful life events or psychosocial stress may play a role in the exacerbation of asthma symptoms [8]. Sandberg and colleagues suggested an increased risk of asthma attack in relation to bereavement in children with asthma [9]. A UK study found that psychosocial factors including adversities in childhood and stressful life events were related to higher rates of hospitalization for asthma [10]. In Denmark, a cohort study showed that those with high perceived stress had approximately two-fold risk of self-reported asthma incidence [11]. Psychological stress can trigger immune responses and subsequent asthma symptom occurrence, which may be involved in the hypothalamus-pituitary-adrenal axis activation and hyperresponsiveness of both the sympathetic and parasympathetic systems [8,12]. Although the effect of psychological stress on asthma has long been suggested, there is little evidence regarding asthma symptoms such as wheezing in relation to perceived stress in adolescents. Therefore, the purpose of this study is to investigate the relationship between perceived stress and asthma symptoms in a nationally representative sample of Korean adolescents.

Methods

Study subjects

We used data from the 8th Korean Youth Risk Behavior web-based Survey (KYRBS), annually conducted by the Ministry of Education, Korea Centers for Disease Control and Prevention, and the Ministry of Health in the Republic of Korea [13]. The KYRBS used proportional allocation and stratified cluster sampling to acquire a national representative sample of Korean adolescents. The 8th survey was conducted in June 2012; 74,186 students (37,297 middle school and 36,889 high school students) participated, and 72,229 were included in statistical analysis after excluding missing values. The KYRBS, an anonymous online survey, was approved by the institutional review board of Korea Centers for Disease Control and Prevention (2014-06EXP-02-P-A).

Measurements

All information was based on self-reported questionnaire. Perceived stress was evaluated using the question “How much do you usually feel stressed?”, and classified into five ratings, from very high to very low. Asthma symptoms included wheezing and wheezing on exertion during the last 12 months. Past history of asthma was indicated by all participants using the question “Has your doctor ever diagnosed you with asthma?” Household economic status was categorized as very high, high, moderate, low, or very low. Subjective health status was classified as very healthy, healthy, moderate, unhealthy, or very unhealthy. Alcohol consumption and smoking were treated as dichotomous variables of lifetime experience. Self-reported body mass index (BMI) was categorized as underweight (< 18.5 kg/m2), normal (18.5–24.9 kg/m2), or obese (≥ 25kg/m2) according to Asian standards [14]. Because high salt [15] and preservatives such as sulfites [16] in fast food and snacks may also affect airway inflammation, fast food and snack consumption during the last seven days were each considered confounding. The intake frequency was categorized as none, 1–2 times a week, 3–4 times a week, 5–6 times a week, once a day, 2 times a day, or 3 times or more a day. The frequency of physical activity was assessed with the question “How many days did you exercise during the last 12 months?” Exposure to secondhand smoke was evaluated with the question “How many days were you adjacent to others smoking at your home during the last seven days?”, and treated as a dichotomous variable (coded 0 for none; coded 1 for one or more days).

Statistical analysis

The chi-squared test and the t-test were used. Considering the KYRBS’s sampling rate and response rate, we estimated weighted percentages and standard deviations (SDs). We performed multiple logistic regression analysis and the associations of subjective stress ratings with wheezing and wheezing on exertion were expressed as odds ratios (ORs) and 95% confidence intervals (95% CIs). We adjusted for grade (age), sex, asthma history, drinking experience, smoking experience, exposure to secondhand smoke, physical activity, fast food consumption, snack consumption, subjective health status, BMI category, and household economic status. We generated ORs of asthma symptom associated with perceived stress ratings in reference to the lowest stress group, and examined the statistical significance of the ORs’ trend by including perceived stress as a continuous variable in the statistical models. Additionally, we conducted stratified analyses according to asthma history. All analyses were conducted using SAS version 9.3 (SAS institute, Cary, NC).

Results

Of the 72229 participants, 8224 (11.4%) and 14658 (20.3%) reported experiencing wheezing and wheezing on exertion, respectively, during the last 12 months (Table 1). The numbers of students with underlying asthma were 6694 (9.2%) in total, 1797 (21.5%) in those with wheezing, and 2464 (16.8%) in those with wheezing on exertion. Adolescents with wheezing or wheezing on exertion were more likely to have drinking experience, smoking experience, exposure to secondhand smoke, lower socioeconomic status, and more frequent fast food and snack consumption.

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    Table 1:

    General characteristics of study population.

Those who reported very high stress accounted for 11.5% of the total, those with wheezing 20.5%, and those with wheezing on exertion 17.8% (Table 2). In contrast, the proportions of those with very low stress were 2.5% of the total, those with wheezing 1.2%, and those with wheezing on exertion 1.6%. The differences between those with and without asthma symptoms were all statistically significant (p<0.001 for wheezing; p<0.001 for wheezing on exertion).

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    Table 2:

    Subjective stress ratings of study population.

Participants who reported very high stress had higher odds of wheezing (OR, 2.621; 95% CI, 2.040–3.367) and wheezing on exertion (OR, 1.960; 95% CI, 1.638–2.344) relative to those with very low stress (Table 3). ORs of wheezing were 1.208 (95% CI, 0.939–1.555), 1.442 (1.130–1.840), and 1.909 (1.493–2.440) in low, moderate, and high stress groups, respectively (p for trend <0.001). For wheezing on exertion, ORs were 1.003 (0.844–1.193), 1.170 (0.988–1.386), and 1.530 (1.289–1.816) in low, moderate, and high stress groups, respectively (p for trend <0.001).

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    Table 3:

    Odds ratios* of asthma symptoms in relation to subjective stress ratings in adolescents.

In adolescents with asthma history (Table 4), ORs of wheezing were 1.247 (95% CI, 0.729–2.132), 1.491 (0.898–2.477), 1.676 (1.002–2.804), and 2.011 (1.171–3.452) in low, moderate, high, and very high stress groups, respectively (p for trend <0.001). The OR of wheezing on exertion was 1.746 (95% CI, 1.110–2.748) in those with very high stress.

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    Table 4:

    Odds ratios* of asthma symptoms in relation to subjective stress ratings in adolescents by asthma history.

Discussion

In this cross-sectional study using a nationally representative sample of Korean adolescents, we found the positive association of perceived stress with wheezing and wheezing on exertion in adolescents aged 13 to 18 years. Those with the highest rating of stress had roughly three-times odds of wheezing compared to those with the lowest rating of stress, and the ORs of asthma symptoms rose with stress ratings in a dose-response manner. Among adolescents with asthma history, perceived stress was significantly associated with asthma symptoms.

Previous studies have suggested the increased risks of asthma incidence and medical care visits for asthma in relation to psychological stress. Psychological stress derived from bereavement may increase the risk for asthma attack in asthmatic children [9]. Stressful life events in children may be related to asthma hospitalization risk [10], and higher perceived stress may induce higher asthma incidence [11]. In the present study, 9.8% and 18.5% of subjects without asthma history reported wheezing and wheezing on exertion, respectively, in the last 12 months. These adolescents’ symptoms might not have been due to asthma, and some may have had undiagnosed asthma. However, regardless of their true prevalence of asthma, it is possible that high perceived stress induces airway hyper responsiveness even in healthy adolescents. There is a need to conduct longitudinal studies of psychological stress levels and asthma symptom occurrence in healthy adolescents.

Numerous biomarker studies have supported the linkage between psychological stress due to various stress factors and asthma symptom occurrence via immune responses. Some studies found increased interleukin levels and immune cells after academic examinations in asthmatic adolescents [17,18]. Low socioeconomic status can cause chronic stress, and Chen and colleagues suggested that chronic stress may mediate the pathways between socioeconomic status and immune responses such as production of interleukin-5 and interleukin-13 in children with asthma [19]. In our study, the major reasons of perceived stress included academic grades (54.6%), conflicts with parents (15.3%), appearance (10.2%), and conflicts with peers (8.7%). Because these factors are intertwined and function with complexity, it would be difficult to indicate which reason caused our subjects’ chronic stress. However, individuals’ responses to stress factors and coping abilities may vary [20], so perceived stress ratings may be a reasonable basis for investigating the effect of psychological stress.

Our study is strengthened by using a nationally representative sample of adolescents in the Republic of Korea, and found that high perceived stress may increase asthma symptom occurrence both in asthmatic and non-asthmatic adolescents. However, there are several limitations to be considered. First, our study was cross-sectional, and thus may be lacking in temporal relationship. Asthma symptoms might increase perceived stress, but health problems were the least frequent reason for stress, at 1.7% (N=1280), in our sample. Nonetheless, our results should be cautiously interpreted due to the possibility of reverse causation. It is still possible that adolescents suffering from asthma symptoms might have been susceptible to stressful events or factors. Second, all information was based on self-report. For example, self-reported weight and BMI may be underestimated [21], although obesity is regarded as an important factor for asthma [5]. Direct measurement of height and weight may be helpful in future studies.

In conclusion, we conducted a cross-sectional study using a nationally representative sample, and suggested the positive associations of perceived stress ratings with wheezing and wheezing on exertion in Korean adolescents. The associations were significant both in asthmatic and healthy adolescents.

  1. Global Asthma Network (2014) The Global Asthma Report 2014. Auckland, New Zealand .
  2. Strachan DP, Cook DG (1998) Health effects of passive smoking. 6. Parental smoking and childhood asthma: longitudinal and case-control studies. Thorax 53: 204-212 .
  3. Nordling E, Berglind N, Melen E, Emenius G, Hallberg J, et al. (2008) Traffic-related air pollution and childhood respiratory symptoms, function and allergies. Epidemiology 19: 401-408 .
  4. Weiland SK, von Mutius E, Husing A, Asher MI (1999) Intake of trans fatty acids and prevalence of childhood asthma and allergies in Europe. ISAAC Steering Committee. Lancet 353: 2040-2041.
  5. Chinn S, Rona RJ (2001) Can the increase in body mass index explain the rising trend in asthma in children? Thorax 56: 845-850 .
  6. Murray CS, Poletti G, Kebadze T, Morris J, Woodcock A, et al. (2006) Study of modifiable risk factors for asthma exacerbations: virus infection and allergen exposure increase the risk of asthma hospital admissions in children. Thorax 61: 376-382 .
  7. Burr ML, Emberlin JC, Treu R, Cheng S, Pearce NE, et al. (2003) Pollen counts in relation to the prevalence of allergic rhinoconjunctivitis, asthma and atopic eczema in the International Study of Asthma and Allergies in Childhood (ISAAC). Clin Exp Allergy 33: 1675-1680 .
  8. Chen E, Miller GE (2007) Stress and inflammation in exacerbations of asthma. Brain Behav Immun 21: 993-999 .
  9. Sandberg S, Paton JY, Ahola S, McCann DC, McGuinness D, et al. (2000) The role of acute and chronic stress in asthma attacks in children. Lancet 356: 982-987 .
  10. Wainwright NW, Surtees PG, Wareham NJ, Harrison BD (2007) Psychosocial factors and incident asthma hospital admissions in the EPIC-Norfolk cohort study. Allergy 62: 554-560 .
  11. Rod NH, Kristensen TS, Lange P, Prescott E, Diderichsen F (2012) Perceived stress and risk of adult-onset asthma and other atopic disorders: a longitudinal cohort study. Allergy 67: 1408-1414 .
  12. Lehrer PM, Isenberg S, Hochron SM (1993) Asthma and emotion: a review. J Asthma 30: 5-21 .
  13. Korea Centers for Disease Control and Prevention (2015) The Eleventh Korea Youth Risk Behavior Web-based Survey, 2015, Ministry of Education, Ministry of Health and Welfare, Korea Centers for Disease Control and Prevention.
  14. World Health Organization Western Pacific Region, International Association for the Study of Obesity, International Obesity Task Force (2000) Redefining Obesity and Its Treatment. Sydney: Health Communications .
  15. Demissie K, Ernst P, Gray Donald K, Joseph L (1996) Usual dietary salt intake and asthma in children: a case-control study. Thorax 51: 59-63 .
  16. Vally H, Misso NL, Madan V (2009) Clinical effects of sulphite additives. Clin Exp Allergy 39: 1643-1651 .
  17. Liu LY, Coe CL, Swenson CA, Kelly EA, Kita H, et al. (2002) School examinations enhance airway inflammation to antigen challenge. Am J Respir Crit Care Med 165: 1062-1067 .
  18. Kang DH, Coe CL, McCarthy DO (1996) Academic examinations significantly impact immune responses, but not lung function, in healthy and well-managed asthmatic adolescents. Brain Behav Immun 10: 164-181 .
  19. Chen E, Hanson MD, Paterson LQ, Griffin MJ, Walker HA, et al. (2006) Socioeconomic status and inflammatory processes in childhood asthma: the role of psychological stress. J Allergy Clin Immunol 117: 1014-1020 .
  20. Parkes KR (1986) Coping in stressful episodes: the role of individual differences, environmental factors, and situational characteristics. J Pers Soc Psychol 51: 1277-1292 .
  21. Bae J, Joung H, Kim JY, Kwon KN, Kim Y, et al. (2010) Validity of self-reported height, weight, and body mass index of the Korea Youth Risk Behavior Web-based Survey questionnaire. J Prev Med Public Health 43: 396-402 .

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