Discussion
This study aimed to assess the prevalence of MH and TTH headaches and their association with screen use characteristics among a large student sample. This study observed that the prevalence of TTH, MH and mixed headache were 47.08%, 26.07% and 14.75%, respectively. An exposure–response relationship was also observed between screen exposure duration and headaches associated with online education use. The study also identified associations between various personal medical conditions (depression, insomnia, eye problems and hearing problems) and different types of headaches based on different patterns of screen usage.
Previous research has investigated the relationship between screen usage and headaches, employing diverse methodologies and diagnostic approaches.10–14 Our findings also aligned with the existing research where increased screen usage was associated with more frequent headaches. Nevertheless, the diverse range of screen usage patterns, particularly with regard to smartphone/tablet usage, has consistently posed a limitation in many studies.23 For example, compared with computer and TV usage, daily smartphone/tablet usage is typically more sporadic and inconsistent, posing challenges in accurately self-reporting screen time.14 This study used screen usage data obtained from the built-in smartphone/tablet software, offering a precise screen usage report. In addition, screen usage patterns may vary based on their intended purposes (entertainment vs education). Therefore, in this study, screen use data were collected separately for entertainment and education purposes and included in the logistic regression models, which helped to reduce the potential influence of confounding factors. For example, constant screen use patterns are common in education, whereas in entertainment, one may use screen with sufficient intervals (table 2). Therefore, we also found lower odds of MHs in participants who used 6–12 hours of the screen for entertainment, probably due to the non-continuous usage of entertainment. However, >12 hours of use were associated with higher odds of MHs, although statistically not significant. Additionally, the participants were naïve to online education, allowing us to assess the impact of a sudden increase in screen usage exclusively. Moreover, prior studies could not compare MH and TTH14 whereas this study could differentiate and compare MH and TTH using a validated screening tool (HSQ-EV scale) which can determine MH and TTH with high specificities (0.95 and 0.86, respectively).15
A recent systematic review and meta-analysis including seven articles found a significant relationship between smartphone/tablet use and headache.24 Likewise, our study also established the detrimental role of smartphones/tablets compared with other devices in headaches. However, the underlying mechanism behind this issue is still unclear. Some studies suggested possible damage to the blood-brain barrier25–28 or involvement of the dopamine–opiate system29 30 on exposure to smartphone microwaves. In contrast, others mostly condemned the eye strain caused by screen resolution or viewing distance/angle.31 However, some prior research identified screen characteristics (eg, screen brightness, frequency of screen band light, flickering, glare) as a possible trigger while some highlighted gradual lowering of migraine cascade threshold on repeated long-term exposure.32 33 Besides, according to Ranasinghe et al,34 prolonged screen exposure leading to chronic accommodation, stress and fatigue of the eye muscles can lead to headaches.34 Further research found that postural problems related to screen exposure, such as improper placement of the screen, inappropriate table or chair height, or close distance between eye and screen, resulting in unnecessary stretching or forward bending, often resulting in a muscular sprain, can cause primary headache.31 Future research can help understand the actual mechanism behind this issue. Specifically, understanding the role of different light bands, screen quality and other device characteristics can significantly add to current knowledge.
Lastly, prior studies identified being female, depression,35 36 insomnia37 and eye problems38 as aggregating factors of different types of headaches. The current study also linked these conditions to MH and TTH using validated and pretested methods. However, depression was the only condition that was consistently present as an aggregating factor in all headache types (TTH, MH and mixed). Therefore, the role of mental healthcare, adequate sleep and ocular care in preventing headaches can be explored in future studies.
The study has certain limitations that should be acknowledged. First, this study included a cross-sectional design, precluding any causality inference. Also, the HSQ-EV tool was used to differentiate between types of headaches as a screening tool rather than a diagnostic tool. Usually, the clinical diagnosis of headache is made by neurologists according to the International Classification of Headache Disorders criteria.39 However, HSQ has high specificity and high negative predictive value in terms of determining headaches, which makes it a suitable tool for determining migraine and TTH headaches.40 Furthermore, our study was conducted during COVID-19; therefore, the possibility of secondary headaches cannot be ruled out. In addition, it is necessary to consider the potential impact of using non-probability sampling methods and online data collection. Such methods can influence the generalisability and may result in inaccurate data reporting. In order to mitigate these challenges, researchers recruited a large sample size and employed personalised communication techniques to reach the target participants. Despite limitations, this study generated compelling evidence on-screen use and associated headaches using a validated headache and screentime assessment, considering potential confounders and large nationally representative samples.
This study examined the relationship between screen time and the occurrence of the two most prevalent types of headaches. Longer duration of screen exposure and smartphone usage were found to have a significant association with headaches. Further, longitudinal studies are required to establish the causal relationship of this association. Considering the inevitable proliferation of screen use among students, more efforts directed towards educating students on the proper use of electronic devices can be considered to mitigate the negative consequences.