Google Trends Useful for Assessing Global Burden of IBS

The global prevalence of irritable bowel syndrome (IBS) has been estimated at 11%, but data vary widely, sometimes even for similar regions or within countries. For example, estimates of the prevalence in Iran range from 1% to 22%. Potential explanations are changes in the definition of IBS, no gold standard for diagnosis, differing data collection methods and studies of different sub-populations within a region.

Subscribe to the latest updates from Digestive Health Advances in Motion

Thank you for subscribing!

Error: Please enter a valid email address.

Email Address Submit

Google Trends is a web-based tool that aggregates data on the popularity of Google search terms. While it cannot determine the prevalence or incidence of a disease, it has been used to determine patterns of interest in a disease or treatment by region and time period.

Ryan Flanagan, MD, MPH, former clinical fellow in the Department of Medicine at Massachusetts General Hospital (now a GI fellow at Brigham and Women's Hospital), Braden Kuo, MD, MSc, director of the Center for Neurointestinal Health, and Kyle Staller, MD, MPH, director of the Gastrointestinal Motility Laboratory at the Division of Gastroenterology, recently conducted the first study to use Google Trends in gastroenterology. In Digestive Diseases and Sciences, they provide proof of concept that the app is worthwhile for investigating the burden of IBS and presumably other functional gastrointestinal disorders.

Study Methods

The team compiled data on Google searches in 137 countries between January 2014 and January 2018. The countries were selected because they had data available on the gross domestic product (GDP) per capita (a proxy for socioeconomic status, which might affect internet access, education, health literacy and health outcomes) and physician density (which might affect population-level knowledge about IBS, health literacy and engagement with medicine).

The popularity of a search team was measured by the number of searches for that term relative to the number of searches for all other terms over the study period.

Interest in IBS

The 10 countries in which searches on "irritable bowel syndrome" were most popular spanned various continents and had a wide range of GDP per capita. Two countries tied for first place, the U.K. and Libya. The 10 countries with the lowest popularity of IBS were generally located in Asia and most had GDP per capita <USD $20,000.

On average, searches on IBS increased 13% during the study period. Among the ten most populous countries studied, the greatest changes were in Pakistan (+64%), Indonesia (+61%) and Russia (+54%). India (−16%) and Nigeria (−35%) had decreases in interest. The change in the U.S. was +28%.

Comparison with Other Data

The researchers compared the Google Trends popularity data with a paper published in Clinical Epidemiology in 2014, which aggregated previously reported estimates of IBS prevalence for 36 countries. There was a poor correlation between the datasets, indicating the published prevalence data are not closely linked with the popularity of IBS as a search topic.

Gross domestic product and physician density were not strong predictors of country-level interest in IBS.

IBS Treatments

Among their findings, researchers identified two major trends:

1. Change in popularity—Among nine common IBS therapies investigated, searches for antidiarrheal medications, probiotics and FODMAP increased the most during the study period, by averages of 46%, 71% and 117%, respectively
2. Popularity by country—There was wide variability in which countries showed the greatest interest in each of the nine therapies. The U.S. was in the top five of countries interested in probiotics, gluten-free diet and peppermint extract

Toward Better Global Assessment

In many parts of the world, the ability to perform proper epidemiological studies of IBS is limited by resources and evolving definitions. The popularity of IBS as a search term does not equate to its prevalence, but countries with a greater proportion of searches for IBS probably have a greater proportion of people concerned with or affected by the condition.

Thus, using Google Trends to assess interest in IBS and other functional gastrointestinal disorders allows the study of disease burden around the world, which will facilitate comparisons between regions.

view original journal article Subscription may be required

Visit the Division of Gastroenterology

Refer a patient to the Division of Gastroenterology