Determination of salivary cortisol and salivary pH level in gaming teenagers – A cross-sectional study

Abstract

Introduction

Internet gaming disorder and cybervictimization has a disproportionate increase during the COVID 19 pandemic. Teenagers and adolescents have high risk for addiction to online gaming. Online gaming increases the stress level of the users affecting the general and the oral health. The study aims to determine the salivary cortisol and salivary pH among the gaming teenagers.

Materials and methods

The cross-sectional study recruited 45 gaming teenagers with the mean age of 15.5 years. The participants were stratified according to the type of online gaming played as mind, aggressive and betting gaming. Their salivary pH and salivary cortisol were assessed. The collected data was analyzed using SPSS version 23.

Results

The mean salivary pH was found to be less among females playing aggressive games (7.11 ± 0.30) and males playing mind games (7.24 ± 0.16). Salivary cortisol level was found to be statistically high in males (6.66 ± 1.33) and females (7.82 ± 0.66) playing aggressive games. The sub-group analysis of salivary pH and cortisol for gender showed a significant difference in the mean salivary cortisol level (p < 0.05) with no difference in the salivary pH (p > 0.05). Based on the number of hours spent in online gaming, there was a significant increase in the mean salivary cortisol level among the participants playing >3 h (p < 0.05).

Conclusion

Salivary cortisol is high among individuals playing aggressive games compared to mind and betting games. Also, salivary cortisol is high in females compared to males with no change in salivary pH.

Graphical abstract

1. Introduction

Over the past decades, the internet has become an integral part of our daily lives across school, work and leisure.¹ Preoccupation with the internet, spending longer time online to achieve gratification, unsuccessful attempts to reduce or quit internet use, irritability associated with cut-down or quit attempts, concealment about the use of internet usage, negatively impacted school, work or relationships are the criteria for internet addiction.² Online entertainment became very popular because of its easy access and availability in many choices. Online gaming which is a part of online entertainment represents a pervasive leisure activity beginning in the middle childhood and continuing through adolescence.

COVID 19 pandemic has led to an unprecedented situation with incalculable health, social and economic consequences.³ This pandemic has forced the government to restrict mobility and stay indoors.⁴ On one hand information and communication technologies enable the instant, reliable dissemination of information to the global population and also forms the savior of knowing information about the pandemic. On the other hand, the development in technology has led to several risks of spending a long time on online gambling, video games, online shopping which has led to serious risk of disorderly, addictive and aggressive behavior.⁵ This behavioral change will make a person to exhibit violence.⁶ Cybervictimization type of studies have proven that people experience greater distress from cyber threats compared to traditional bullying. The intensity of use of online gaming has direct correlation with the risk of cybervictimization which are associated with two psychological factors such as self-esteem and social anxiety.⁷ Online gaming has two opposing points of views. One point of view is that online games which use violent content increases the level of hostility and cruelty among the players. All the aggressive and monetary or betting type of games come under this point of view. The other point of view is that some online games can be an important educational tool and individuals get benefitted by communicating with other gamers. Mind type of games come under this category.⁷ The main aim of cybervictimization is to deteriorate the emotional sphere and social relation of victim which includes various forms of behavior such as playful or friendly teasing to threats, insults or even psychological virtual terror leading to stress, depression or even suicide. Researches categorize aggression into two such as reactional and instrumental. Reactional aggression arises as a reaction to frustration whereas intentional aggression is a planned behavior that uses aggression to achieve a goal.⁸ The reasons for online gaming include striving for excellence, sense of inferiority, envy, revenge. The excessive and recurrent use of devices such as mobile phones, tablets, and computers for the purpose of online gaming resulting in significant compromise of daily activities and distress may be termed as gaming disorders.⁹ Studies have shown that online gaming leading to cybervictimization can have serious consequences on health of digital users.¹⁰ Owing to this pandemic COVID 19, many teenagers are addicted to this gaming and hence may develop various ill-effects.¹¹ The COVID 19 lockdowns have boosted the revenues for many gaming companies. With the practice of social distancing reducing consumer and business activity to a minimum, gaming offers an engaging distraction for people at home looking for social interaction, and data usage shows huge growth in playing time and sales since lockdown.¹² There are lists of various games played by the teenagers. Violent mobile games lead to the development of aggressive behavior and reduced empathy in real life as evidenced by previous researchers.¹³ India has been ranked number one in global mobile game downloads in the first nine months of 2020.¹⁴ The country's citizen installed 7.3 billion games, nearly 17% of all worldwide downloads as the gaming craze continued.¹⁵

Engaging in mobile gaming affects the sleep by causing increased sleep-onset latency and sleep deficiency and also causes stress.¹⁶ Stress is characterized by release of neuropeptide from the hypothalamus and pituitary which acts at the adrenal glands.¹⁷ In response, adrenals produce the glucocorticoid, cortisol, which can travel throughout circulation to brain to act in hypothalamus to down regulate its own production and act at other central targets to promote the physiological and psychological effects that are associated with stress.¹⁸ A study has shown that Hypothalamic-pituitary-adrenal (HPA) stress axis factors such as cortisol may play a role in pathological addiction. HPA axis show a circadian oscillation which couples glucocorticoid synthesis to diurnal patterns. Thus, serum cortisol peaks in morning and becomes low at night. HPA is the central stress response system which helps in coping stress response and restores homeostasis.¹⁹ Cortisol secreted during stress exhibits a negative feedback mechanism on HPA axis. Cortisol stimulates HPA axis which in turn increases the secretion of corticotropin releasing hormone (CRH) which stimulates anterior pituitary to secrete adreno corticotropic hormone (ACTH) which in turn stimulates cortical portion of adrenal gland to secrete cortisol during stress. Also, cortisol aims metabolites and affects the ion transport (sodium and potassium transport), immune response (blocks T-cells proliferation by preventing T-cells from recognizing interleukin signals) and even memory (hippocampus atrophy).²⁰ Salivary pH is an important factor in determining the nature of oral environment. Saliva contains a variety of molecular and bacterial compounds that can change with systemic pathologies.²¹ Saliva turns to be acidic, increasing the chances of development of oral health problems.^22,23 Hence, salivary pH is an important oral health indicator.

To begin to elucidate the role of Hypothalamic-pituitary-adrenal (HPA) stress axis function among teenagers, salivary cortisol level is determined by collecting the saliva. Salivary samples were collected in baseline from the gaming teenagers, we anticipated that the gamers would have an attenuated HPA response for exposure to online games when compared to recreational games. Hence this study was conducted to determine the salivary cortisol and salivary pH in the gaming teenagers.

2. Materials and method

A cross-sectional study was designed to assess the salivary cortisol and salivary pH in the gaming teenagers. A self-administered questionnaire containing nine questions was given to the participants. The questionnaire consisted of demographic details, type of online gaming played, hours spent in gaming, devices used to play, money spent on virtual gaming, reason for playing online gaming. Salivary samples were collected from the gaming teenagers to detect the pH and salivary cortisol. Ethical approval to conduct the study was obtained from the authors Institutional review board (IRB). Informed consent was obtained from parents of the teenagers after clearly explaining the purpose of the study.

Individuals of age 12–19 years irrespective of their gender who do online gaming were included in the study. Differently abled teenagers, individuals with systemic illness and under medication were excluded from the study. Convenient sampling method was employed to recruit the participants. A total of 45 teenagers with different types of online gaming were selected and grouped. Most of the teenagers were often playing mind games, aggressive and betting games. Hence, 15 participants in each of the above-mentioned groups were recruited. Group I - 15 participants who played mind games, Group II -15 participants who played aggressive games and Group III - 15 participants who played betting games.

A sugarless chewing gum was given to the participants and was asked to chew for 5 min. Then the stimulated saliva was collected in the sterile saliva collecting container (HIMEDIA, Sterile Uricol (PW016)). The saliva was collected in the morning 2 h after breakfast. Immediately after collecting the stimulated saliva, salivary pH was measured using pH meter. Saliva was stored at −2 to - 4-degree Celsius temperature for 2 h and sent to the laboratory to determine the salivary cortisol level. Salivary cortisol was measured using cortisol ELISA (The enzyme-linked immunosorbent assay) kit (Fig. 1). The salivary cortisol assay was performed using cortisol assay test kit purchased from Siemens. DRG salivary cortisol ELISA kit was used. Free cortisol in saliva was measured using ELISA test kit. Saliva standards were pipetted into a clear microtiter plate coated with an antibody to capture antibodies. A cortisol-peroxidase conjugate was added to the wells. The binding reaction was initiated by the addition of a monoclonal antibody to cortisol. After 1 h incubation the plate was washed and substrate was added. The substrate reacts with the bound cortisol-peroxidase conjugate. After a short incubation, the reaction was stopped and the intensity of the generated color was detected in a microtiter plate reader at 450 nm.

Fig. 1.

Cortisol ELISA test kit.

The data collected for salivary cortisol and salivary pH was analyzed in statistical package of social sciences (SPSS version 23). Normality test was performed using Shapiro-Wilk numerical test method. Descriptive statistics was performed to report the mean and standard deviation of salivary cortisol and salivary pH. One-way ANOVA test with Tukey's post-hoc test was employed to compare the mean of salivary cortisol and pH between the groups. A sub-group analysis for the based on the number of hours spent in online gaming was also performed. P value less than 5% was considered significant.

3. Results

The mean salivary pH of females was found to be high among the participants playing betting games (7.45 ± 0.12). Also, the mean salivary pH of males was found to be high among the participants playing aggressive games (7.33 ± 0.22). However, the mean salivary cortisol level was found to be high among males and females playing aggressive games (6.66 ± 1.13; 7.82 ± 0.66) respectively (Table 1). The mean comparison of salivary pH and cortisol showed no statistical difference in the age and salivary pH (p > 0.05). However, there was a statistically significant difference in the salivary cortisol among the participants playing mind, aggressive and betting games for >3 h (p = 0.000) as shown in Table 2. Pair-wise comparison of sub group analysis for salivary cortisol using Tukey's post-hoc test showed statistically significant mean difference between aggressive and mind games; aggressive and betting games (p = 0.002; 0.000 respectively) for >3 h gaming. There found to be no significant mean difference between mind and betting games based on number of hours played (p = 0.500). The mean difference was high between aggressive and betting games shown in Table 3. The sub-group analysis of salivary pH and cortisol for gender showed a significant difference in the mean salivary cortisol level (p > 0.05) with no difference in the salivary pH (p > 0.05) as shown in Table 4. A pair-wise comparison of sub-group analysis showed a significant mean difference between aggressive and betting games among males and females with a p value of 0.002 and 0.001 respectively. However, there was a significant mean difference between aggressive and mind games among the females (p = 0.000) as shown in Table 5.

Table 1.

Mean distribution of age, salivary pH and salivary cortisol among the participants in the groups.

Group	Gender	N	Mean ± SD
			Age	Salivary pH	Salivary cortisol (ng/ml)
Mind games	Male	10	15.8 ± 1.87	7.24 ± 0.16	5.56 ± 1.30
	Female	5	14.8 ± 2.49	7.39 ± 0.33	5.12 ± 0.61
Aggressive games	Male	7	15.8 ± 2.03	7.33 ± 0.22	6.66 ± 1.13
	Female	8	15.2 ± 1.38	7.11 ± 0.30	7.82 ± 0.66
Betting games	Male	9	15.6 ± 1.50	7.32 ± 0.29	4.47 ± 0.75
	Female	6	15.0 ± 1.78	7.45 ± 0.12	5.75 ± 1.20

Table 2.

Mean comparison of salivary pH and salivary cortisol based on number of hours spent in gaming using sub-group analysis.

Group	Hours Spent on Gaming	Mean ± SD			F value	p value
		Mind games	Aggressive games	Betting games
Salivary pH	≤3 h	7.30 ± 0.13	7.34 ± 0.15	7.47 ± 0.14	3.453	0.054
	>3 h	7.30 ± 0.35	7.17 ± 0.32	7.26 ± 0.31	0.325	0.726
Salivary Cortisol	≤3 h	5.28 ± 1.03	6.05 ± 0.82	5.00 ± 1.13	1.356	0.283
	>3 h	5.62 ± 1.29	7.72 ± 0.75	4.96 ± 1.19	17.462	0.000

Table 3.

Pair-wise comparison of salivary pH and salivary cortisol based on number of hours spent.

Hours spent	Group comparison	Salivary pH			Salivary cortisol
		Mean Difference	p value	95% CI	Mean Difference	p value	95% CI
≤3 h	Mind games Vs Aggressive games	−0.045	0.856	−0.261 to 0.171	−0.772	0.452	−2.376 to 0.832
	Aggressive games Vs Betting games	−0.131	0.303	−0.351 to 0.083	1.050	0.255	−0.584 to 2.684
	Betting games Vs Mind games	0.176	0.047	0.002 to 0.350	−0.277	0.849	−1.575 to 1.019
>3 h	Mind games Vs Aggressive games	0.117	0.749	−0.288 to 0.523	−2.111	0.002	−3.438 to −0.783
	Aggressive games Vs Betting games	−0.090	0.827	−0.477 to 0.296	2.770	0.000	1.505 to 4.035
	Betting games Vs Mind games	−0.026	0.987	−0.472 to 0.418	−0.659	0.500	−2.115 to 0.796

Table 4.

Sub-group analysis of salivary pH and salivary cortisol for gender.

Variable	Gender	Between groups
		Mean square	F value	p value
Salivary pH	Male	0.023	0.426	0.658
	Female	0.228	3.084	0.074
Salivary cortisol	Male	9.503	7.936	0.002
	Female	13.45	18.28	0.000

Table 5.

Pair-wise comparison of sub-group analysis of salivary cortisol for gender.

Gender	Groups	Mean Diff	P value	95% CI
Male	Aggressive vs Mind games	1.097	0.127	−0.253 to 2.448
	Aggressive vs Betting games	2.191	0.002	0.809 to 3.572
	Mind vs Betting games	1.093	0.097	−0.166 to 2.352
Female	Aggressive vs Mind games	2.705	0.000	1.443 to 3.967
	Aggressive vs Betting games	2.075	0.001	0.879 to 3.271
	Mind vs Betting games	−0.630	0.463	−1.971 to 0.711

4. Discussion

The hypothesis that HPA stress axis responding would be weakened among aggressive games compared to recreational games was endorsed. There were significant differences by gender to influence HPA stress axis responding among the gaming teenagers. These findings support and extend our understanding of the attenuated HPA axis in teenagers playing aggressive games.

In the present investigation, aggressive gamers playing online games for > 3 h demonstrated an attenuated HPA response compared to mind games playing teenagers. Similarly, Children in the violent game addiction had higher cortisol levels during game play than children in nonviolent condition, thus it confirms the activation of sympathetic nervous system.²⁴ The results of the present study in consistent with the study conducted by Hossini et al. in which the violent video games have led to a significant increase in the level of salivary cortisol while playing and cortisol level was constant after the game.²⁵ There was a significant association by gender to influence the salivary cortisol in the present study as the females presented the higher salivary cortisol level than the males. Previous studies have demonstrated that depending on many factors including age, health and menstrual cycle, there is an increased salivary cortisol level in females.^26,27 Women demonstrate a greater lability in cortisol response to physiological arousal with a much larger peak in salivary cortisol than men.²⁸ In another study conducted with pathological gamblers and recreational gamblers, the male pathological gamblers demonstrated a stronger attenuation of HPA activation than the recreational gambling men.¹⁸

This study found no significant difference in the pH of saliva. However, salivary pH was found to be less in females playing aggressive games (7.11 ± 0.30). Previous study conducted to assess the salivary pH of gamers and non-gamers found that the salivary pH was less in gamers compared to the non-gamers.²⁹ Decrease in pH can be seen in stressed, depressed situations, these stressful situations might develop from increased gaming causing the decrease in salivary pH and increase in acidity of saliva (acidic pH). In the current study pH was normal among all the teenagers irrespective of their gaming group.

It has been characterized that generation of reactive oxygen species (ROS) by activated phagocytes at gingival sulcus initiates destruction of connective tissue causing periodontitis. ROS are produced during mitochondrial oxidative metabolism as a cellular response to cytokines and bacterial invasion.³⁰ These ROS (superoxide, hydrogen peroxide, hydroxyl radicals, hypochlorous acid, and chloramines) cause infection-associated tissues damage. Excess of ROS released by plaque stimulated neutrophils cause oxidative stress and damage critical biomolecules which in turn results in deleterious effects.³¹ Cortisol secreted during stress acts as an oxidative mediator increasing the oxidative stress which seems to highly contribute to periodontitis. Thus, cortisol acts as salivary biomarker in periodontitis.

Increased secretion of cortisol encourages bone fragility through apoptosis of osteocytes through caspase-3 activation resulting in bone surface remodeling. Cortisol increases bone resorption and decreases bone formation showing an impact on differentiation of cells of osteoblastic lineage.³² Cortisol downgrades the expression of core binding factor a1 (Cbfa1), an important factor in osteoblastogenesis, osteocalcin (osteoblast specific gene) and type I collagen (major component of bone matrix). Also, cortisol decreases the replication of cells of osteoblastic lineage which in turn increases osteoblastic and osteocytic apoptosis.³³ Thus, increased cortisol promotes bone resorption in periodontitis.

The limitation of the current study is the small sample size and hence the extrapolation of results to other population remains questionable. Other limitation is that the salivary cortisol was measured using ELISA method which has low specificity. Liquid chromatography method should be used in future studies as it provides good specificity to detect salivary cortisol.

In the present study, a strong correlation was found between online gaming, number of hours spent in gaming and salivary cortisol level which is the indicator of stress and internet gaming disorder. It can be inferred that mobile gaming plays a major role in increasing the stress level of teenagers which leads to a threat for the teenagers addicted to mobile games.

5. Conclusion

In the present study, salivary cortisol acts as a biomarker to measure the level of stress among the gaming teenagers. The salivary pH is alkaline in the teenagers and the oral environment is found to be fair. Females playing online games for >3 hrs had increased salivary cortisol compared to males. Salivary cortisol is increased among the teenagers playing aggressive games than the betting and mind games.

Funding

Nil.

Declaration of competing interest

Nil.