ABC | Volume 114, Nº4, April 2020

Viewpoint Internet Search Trends and Regional Mortality Tendencies: The Case of Oral Anticoagulants and Stroke Roberto Muniz Ferreira, 1, 2 Ísis da Capela Pinheiro, 1,2 João Roquette Fleury da Rocha 1,2 Universidade Federal do Rio de Janeiro – Instituto do Coração Édson Saad, 1 Rio de Janeiro, RJ – Brazil Hospital Samaritano Botafogo – Cardiologia, 2 Rio de Janeiro, RJ – Brazil Introduction Multiple studies have found that up to 30% of ischemic strokes are associated with atrial fibrillation (AF), especially in the elderly population. 1,2 Although the embolic risk varies according to clinical characteristics and comorbidities, anticoagulant therapy has consistently shown to reduce stroke rates by approximately 70%. 1 However, previous studies demonstrated that treatment rates with warfarin were low, even in patients at high risk for embolic events. Despite evidence from various publications demonstrating the effectiveness and safety of vitamin K antagonists, their complex pharmacokinetics and the need for continuous monitoring and frequent dose adjustments were the main explanations for low adherence. 3 Over the last 10 years, four direct oral anticoagulants (DOAC) have become available to prevent embolic events in patients with non-valvular AF: dabigatran, rivaroxaban, apixaban and edoxaban. In August 2011, dabigatran was the first DOAC approved in Brazil for stroke prevention, followed by rivaroxaban four months later. Two years later, apixaban was also introduced in the Brazilian market and only in February 2018 edoxaban became available. When compared to warfarin, multiple trials have suggested that DOACs are non-inferior in preventing ischemic strokes and possibly superior in reducing mortality, perhaps due to fewer intracranial hemorrhages. 4 In addition to waive the need for laboratory monitoring, they have more predictable pharmacokinetics and a lower incidence of drug-to-drug interactions. Recent studies have demonstrated an increase in anticoagulation prescription rates among physicians since DOACs have become clinically available. 1 The analysis of Internet search trends is a promising method for estimating the frequency by which medical interventions are being applied in clinical practice. More recent publications have suggested a strong correlation between Internet search engine query data, medical decision making and pharmacological prescription patterns for a given region. 5 However, it is not clear whether these search patterns are also predictive of regional trends associated with clinical events. Internet search trends in health care Currently, Google is perhaps the most utilized online search tool, even among healthcare professionals. The search patterns created within Google have been available since 2004 and can be accessed from Google Trends (Google Inc. Mountain View, CA, USA). Briefly, this is an open-access tool which displays how frequently any given term or topic has been searched for in the Google search engine. Additionally, filters can be used to specify a region and time period for the analysis. The frequency is presented as a number from 0 to 100 which varies over the predefined time interval and represents a proportion in relation to the highest popularity point. Accordingly, a value of 100 indicates the moment at which the term or topic reached the highest search interest, and a value of zero correlates to less than 1% of the peak popularity. 6 Also, up to five terms or topics can be analyzed simultaneously, and a mean popularity value is automatically provided for each term during the selected interval. Internet search engines have the potential to reflect the general interest of a population in a given topic, within a specific time interval and region. Google Trends is an example of such a tool, and the scores provided the website are a result of many factors that directly influence the public’s awareness regarding the subject being researched. These include promotional campaigns, media coverage, internet access, literacy rates and socioeconomic status. Nevertheless, when patients and health care professionals are exposed to information and knowledge, there is a higher probability of an informed decision regarding the implementation of medical interventions. A study by Kritz et al. 7 demonstrated that physicians frequently use general search engines to retrieve medical knowledge in daily practice, chiefly because of lack of time for a more thorough research. 7 Furthermore, some countries use search engines as epidemiological surveillance tools for a variety of diseases, which could have implications in public health policies. In France, the Sentinel Network is a public health monitoring system where general practitioners use web-based data to follow disease patterns and potentially identify outbreaks at an early stage. 8 Although popularity scores do not necessarily mirror drug prescription patterns, previous studies with a wide variety of medications have suggested that an association does in fact Mailing Address: Roberto Muniz Ferreira • Universidade Federal do Rio de Janeiro - Instituto do Coração Édson Saad - Rua Rodolpho Paulo Rocco, 255. Postal Code 21941-913, Rio de Janeiro, RJ – Brazil E-mail: betomf@terra.com.br Manuscript received November 02, 2019, revised manuscript December 02, 2019, accepted December 27, 2019 Keywords Stroke/prevention and control; Myocardial Ischemia/ prevention and control; Pharmaceutical Services, Online/ trends; Anticoagulants/therapeutic use; Varfarin; Dabigatran; Rivaroxaban; Mortality/trends. DOI: https://doi.org/10.36660/abc.20190768 726