Background A pilot study conducted in academic 2017/18 among undergraduates of the University of Sarajevo showed energy drinks to be most frequently consumed during academic activity, less frequently mixed with alcohol in leisure, and rarely in the sports activity. The aim of this study was to assess the impact of the COVID-19 pandemic on energy drinks consumption among undergraduates of the same University, with a focus on their consumption during exams. Study design A cross-sectional study was conducted by an online questionnaire. Methods The questionnaire, mainly based on the Consortium Nomisma-Areté questionnaire, was customized to compare energy drinks consumption before and during the COVID-19 pandemic, and distributed among students between July 26th, 2020 and April 3rd, 2021. Results Out of 1,045 students who chose to participate in the study (participation rate of 14.7%), 653 students, mostly women, attending the lower study years, reported energy drinks consumption. Both be-fore and during pandemic, overall energy drinks consumption was most frequently reported as rare [281 (43.9%) before, 326 (51.2%) during the pandemic], and exams-related energy drinks consumption as once or twice a week [156 (43.8%) before, 130 (42.1%) during pandemic]. The pandemic increased the number of frequent consumers (consumption of 4-5 energy drinks per week) in both overall [35 (5.5%) before, 46 (7.2%) during pandemic] and exams-related energy drinks consumption [42 (11.8%) before, 48 (15.5%) during pandemic]. Study year (OR=0.842; 95% CI 0.77-0.921; p<0.001), being single and living alone [OR=0.512; 95% CI 0.296-0.883; p=0.016), or living with a partner and children [OR=0.377; 95% CI 0.168-0.847; p=0.018) were identified as negative independent predictors for exams-related energy drinks consumption, while being a regular smoker (OR=0.429; 95% CI 0.223-0.875; p=0.011) appeared its new negative independent predictor during pandemic. Conclusions The pandemic seemed to decrease both the overall and exam-related energy drinks consumption among undergraduates of the University of Sarajevo with the exception of a portion of already frequent energy drinks consumers.

BACKGROUND Indoor air quality (IAQ) in classrooms affects children's health and academic perfor-mance. The aim of this pilot study was to determine IAQ in elementary schools different in their inter-nal and external characteristics, in settings of COVID-19 epidemics. METHODS IAQ parameters: fine particulate matter (PM2,5) mass concentration, CO2 concentration, tempera-ture and relative humidity were measured in parallel in four elementary schools/classrooms during October (non-heating season) and four months (including holiday in January) of heating season. IAQ parameters were measured in settings of anti-epidemic restrictions (≤13 students in classroom, frequent ventilation). RESULTS During October, except in one school, PM2,5 concentrations were below the upper recommended value (25 μg/m³), but started rising in all schools in the heating season. The highest concentrations of PM2,5 were registered in two schools with closed or shortly opened windows. CO2 concentrations were mostly in the recommended range (up to 1000ppm) except in the school with constantly closed windows and in three schools in February when concentrations were higher. Except in one, the same school, and in January, both temperature and relative humidity were out of the recommended range (24,0-27,0°C in non-heating; 20,0-24,0°C in heating season; and 45-55%), with temperature mainly above and relative humidity mainly below it in three schools. The largest deviation in temperature and relative humidity were registered in urban schools. Registered differ-ences may be explained by different internal and external characteristics. CONCLUSION Despite anti-epidemic restrictions, most of the measured IAQ parameters were out of the recom-mended values in heating season. In addition, further deterioration of IAQ could be expected if all students had been presented in the classroom. Finally, to assure a healthy school environment in heating season, further optimisation of both indoor and outdoor conditions is needed in both pandemic and non-pandemic settings.