Internet search volumes in brain aneurysms and subarachnoid hemorrhage: Is there evidence of seasonality?

Objective: Results of previous studies examining seasonal variation in the incidence of aneurysmal subarachnoid hemorrhage (SAH) are conflicting. The aim of this brief report is to investigate whether there is a seasonal effect in online search queries for SAH that may reflect an association between meteorological factors and aneurysm rupture.

Patients And Methods: We used the Google Trends data service to analyze the volume of internet queries for SAH on Google's search engine from January 1, 2004 to November 2016. We used comprehensive search terms and collected data from: USA, Canada, and countries known for their high prevalence of SAH (Finland, and Japan), as well as worldwide search volume. Potential seasonal variations in the data were assessed by comparative non-parametric tests and curve-fit regression model.

Results: Our analyses revealed that USA had the highest median value in cumulative search scores (115 vs. 86, 46, 46 for Finland, Canada and Japan, respectively). The term "brain aneurysm" was the commonly used search term among countries, followed by "cerebral aneurysm". There was no evidence of seasonality in any of the countries studied on both univariate tests and regression time-adjusted analysis.

Conclusions: There are no seasonal variations in internet search query volume for SAH. Further studies are needed to explore whether online search volumes correlate with the actual incidence of SAH.