Discussion
Our study revealed that 65.5% of all board-certified cardiologists in Japan received personal payments for activities such as lecturing, consulting, and writing from pharmaceutical companies between 2016 and 2019. The total amount of these payments exceeded $112.9 million, equivalent to approximately 12.3 billion Japanese yen over this four-year period. Although the level of these payments remained stable throughout the study period, a disproportionately small group of cardiologists received the majority of these payments. To the best of our knowledge, this is the first study to explore the comprehensive financial interactions between pharmaceutical companies and cardiologists in a country other than the US.1,2,20
Contrary to findings in the US, where approximately three-quarters of cardiologists reportedly received various personal payments, including compensation, honoraria, travel fees, royalties, and food and beverage payments from pharmaceutical and medical device corporations,1,2 our research in Japan indicates that a mere half of the board-certified cardiologists annually received financial recompense for lecturing and consulting from the pharmaceutical companies. Although the study findings were consistent with previous studies in Japan,11,13-17,19,23-25 this lower percentage of cardiologists in Japan receiving such payments than those in the US would substantially underrepresent the actual degree of their financial engagements with the healthcare companies, given that our study was limited to compensation payments to individual cardiologists and did not encompass other prevalent payment categories or payments from medical device companies, despite that cardiologists frequently utilized medical equipment and devices such as implantable cardioverter-defibrillators, cardiac catheters, and stents.
Although the majority of cardiologists received only modest amounts of payments relative to their overall income as cardiologists, the impact of these payments should not be underestimated. Previous studies in the United States have demonstrated that even small payments to cardiologists from medical device and pharmaceutical companies are significantly associated with increased usage of implantable cardioverter-defibrillators,8 percutaneous coronary interventions,26 stent placements,9and prescriptions for oral anticoagulants27 and antiplatelet drugs.9 Nonetheless, given the absence of studies exploring the associations between payments to cardiologists and their clinical practices, future research is warranted to investigate the impact of industry payments on the clinical practices of cardiologists in Japan.
Additionally, we found that only a small number of cardiologists received the vast majority of personal payments. As we elucidated, the average payments to JCS executive board members12 and cardiology guideline authors18 were substantially larger than those received by the board-certified cardiologists on average. These physicians, often referred to as key opinion leaders, are frequently targeted by pharmaceutical and medical device companies,28-37 due to their authoritative and influential positions.
Given their significant influence on other cardiologists, it is crucial to properly manage COIs among these influential cardiologists. However, previous studies have indicated significant undeclared and underreported COIs between these physicians and pharmaceutical companies in Japan.12,18,28-30,37 Additionally, the policies for managing COIs in Japan are less rigorous and transparent compared to those in other developed countries.28,30,36,37 The study findings further underscore the critical need for effective management of financial COIs among influential cardiologists in Japan.
This study has several limitations. Potential inaccuracies in the payment data reported by companies and in the database may exist. Moreover, the omission of certain types of payments, including meals, travel expenses, and gifts, which are not readily available in Japan, likely leads to a substantial underestimation of the magnitude and proportion of financial relationships between cardiologists and pharmaceutical companies in Japan. Furthermore, as the study encompassed only payments from JPMA-affiliated companies, it may not fully represent the entire range of financial interactions between cardiologists and pharmaceutical companies not affiliated with the JPMA and medical device companies.
Despite these limitations, our study demonstrates that more than 65% of cardiologists certified by the Japanese Circulation Society received personal payments related to lecturing, consulting, and writing from pharmaceutical companies between 2016 and 2019. These payments were concentrated among a small group of cardiologists. Future studies should explore the influence of these payments to cardiologists on their clinical practice in Japan.