In workplaces, where no pollution problems are reported, a significant share of indoor workers (6% of males, 9% of females) suffer “often, at least once a week” from headaches attributed to the working environment.2 This symptom is significantly associated with occupational stress.3 The individual characteristics of workers, in particular anxiety and depression, significantly influence the reporting of headache.4 Among health care workers, headache is associated with occupational stress5 and with sleep problems,6 as well as with anxiety and depression that were significantly increased during the COVID-19 pandemics.7 This study did not take into account these variables. This may be a major limitation because the study population was drawn from high-risk hospital areas such as isolation wards (designated as “pandemic wards”), the emergency rooms and medical intensive care unit. In these settings, workers are highly likely to experience emotional overload. The association between Personal Protective Equipment (PPE) and headache could be, therefore, spurious and the real factor should be sought among the psychosocial factors associated with the pandemic. Furthermore, the study is entirely based on what workers remember of the situation before the epidemic, and this inevitably exposes to a possible recall bias. We are convinced that the association between PPE and headache is worthy of controlled longitudinal studies, which compare different types of PPE and take into account all confounding factors.
- personal protective equipments
- psychosocial factors