Article Figures & Data
Figures
- Figure 1
Google Trends Internet search volume for “ankle swelling,” “swollen ankles,” “swollen feet,” or “swollen legs” in the United States from January 4, 2004 to January 26, 2016.
Horizontal axis markers (Dec, Jun) are centered mid-month. The dashed line is the best-fit sinusoid.
- Figure 2
Google Trends Internet search volume for ‘ankle swelling,’ ‘swollen ankles,’ ‘swollen feet, or ‘swollen legs’ in Australia (◊) and the United States (Δ) (August 29, 2010, to January 26, 2016).
Horizontal axis markers (Dec, Jun) are centered mid-month. The solid line and dashed line are best-fit sinusoids for Australia and the United States, respectively.
Additional Files
The Article in Brief
Seasonality of Ankle Swelling: Population Symptom Reporting Using Google Trends
Scott Garrison , and colleagues
Background It appears that complaints of ankle swelling are more common in summer, however, this observation has not been reported. This study seeks evidence of seasonality based on the public�s Google Internet searches for ankle swelling.
What This Study Found Internet searches for ankle swelling and related terms are highly seasonal, with public interest peaking in midsummer. Analyzing Google Trends data of searches for "ankle swelling," "swollen ankles," "swollen feet," or "swollen legs" originating in the US between 2004 and 2016, seasonality explained 86 percent of the variability in search volume, with the peak of searches occurring in mid-June and the low point in mid-December. To confirm these findings, an identical analysis was conducted for Australia where the seasons are reversed, and found the same pattern. Heart failure admissions have been shown to exhibit the opposite seasonal trend, peaking in winter, which is consistent with the authors' clinical observation that these patients seldom go on to develop cardiovascular disease.
Implications
- The authors call for research on patients with summertime ankle swelling to establish whether such patients have, or go on to develop, cardiovascular pathology. Further research is also needed to establish the mechanism behind the findings, which could potentially include seasonality in contributing factors, such as diet (including salt and water intake) increased activity in summer, or widening of blood vessels due to temperature.
