COVID-19 pandemic and mental health in Spain: an analysis of their relationship using Google Trends./ Pandemia por COVID-19 y salud mental en España: un análisis de su relación utilizando Google Trends.

INTRODUCTION: This study aims to examine the public interest that exists on internet regarding various mental health topics and its relationship with evolution of COVID-19 pandemic in Spain. MATERIALS AND METHODS: Google Trends was used to explore relative search volume (RSV) for the following terms related with mental health (TRMH): "anxiety", "depression", "stress", "insomnia" and "suicide"; between January and December 2020. The cross-correlation function was performed to assess association between new COVID-19 cases and RSV levels for TRMH. Finally, Mann-Whitney test was used to examine differences between RSV values for TRMH before and after of state of alarm declarations on March and October 2020. RESULTS: The "anxiety" term showed the highest RSV indices. A significant correlation was found between new COVID-19 cases and RSV for "anxiety" with a time-lag of +1 week (r=0.49; p<0.05). Was found an increase of SRV for "anxiety" (U=0.00; p=0.01) and a decrease of SRV for "depression" (U=1.00; p=0.04) between 4-week period before and after state of alarm of March 2020. Regarding the state of alarm of October 2020, a higher RSV for "anxiety" (U=0.50; p=0.02) was found in the four weeks after it compared with a similar previous period. CONCLUSIONS: Anxiety is the mental health topic of greatest public interest on internet in context of COVID-19 pandemic. Public concern about anxiety rises one week after the increase in COVID-19 cases and is greater after introduction of control measures that entail any type of mobility restriction or activity limitation. There is a greater general need for information on anxiety at specific times in the pandemic evolution.