Historical trends in health care-related financial holdings among members of Congress

Background Revelations that some members of Congress, including members of key health care committees, hold substantial personal investments in the health care industry have raised concerns about lawmakers’ financial conflicts of interest (COI) and their potential impact on health care legislation and oversight. Aims 1) To assess historical trends in both the number of legislators holding health care-related assets and the value and composition of those assets. 2) To compare the financial holdings of members of health care-focused committees and subcommittees to those of other members of the House and Senate. Methods We analyzed 11 years of personal financial disclosures by all members of the House and Senate. For each year, we calculated the percentage of members holding a health care-related asset (overall, by party, and by committee); the total value of all assets and health care-related assets held; the mean and median values of assets held per member; and the share of asset values attributable to 9 health asset categories. Findings During the study period, over a third of all members of Congress held health care-related assets. These assets were often substantial, with a median total value per member of over $43,000. Members of health care-focused committees and subcommittees in the House and Senate did not hold health care-related assets at a higher rate than other members of their respective chambers. Conclusions These findings suggest that lawmakers’ health care-related COI warrant the same level of attention that has been paid to the COI of other actors in the health care system.


Introduction
Federal lawmakers affect all aspects of the United States health care system. They shape the way that care is financed and delivered, the way that medical research is conducted, and the way that new drugs and medical devices are approved and marketed. Thus, recent revelations that some members of Congress, including members of key health care committees, hold substantial personal investments in the health care industry have understandably renewed concerns about lawmakers' financial conflicts of interest (COI) and their potential impact on health care legislation and oversight [1][2][3][4][5][6].
Despite scrutiny from media and watchdog organizations [7], health care-related COIs among members of Congress have rarely been formally studied by academic researchers. Thus, despite having important implications for public health, many aspects of lawmakers' health care-related COI remain poorly understood. A report from STAT News found that in 2015, roughly 30% of senators and 20% of representatives held health care-related assets [8]. However, it is not clear how these patterns relate to historical averages, making it difficult to assess whether health care-related COI among members of Congress have increased or decreased over time.
Because every lawmaker has the opportunity to vote on health care-related bills, any lawmaker's financial stake in the industry can raise concerns about COIs and their impact on health care legislation. However, those who sit on key health care committees and subcommittees have far greater involvement in the shaping of health care legislation. Thus, health care industry-related COIs among these members are particularly concerning. A 2009 investigation conducted by the Center for Responsive Politics found that 54 members of House and Senate committees with responsibility for health care legislation had personal financial holding in the health care industry [9]. Yet was not clear from this analysis whether these members held health care-related assets at a higher rate than other members of their respective chambers.
To better understand the scope of health care-related COI among members of Congress, we analyzed 11 years of personal financial disclosures by all members of the House and Senate. Our primary aim was to assess historical trends in both the number of legislators holding health care-related assets and the value and composition of those assets. Our secondary aim was to compare the financial holdings of members of health care-focused committees and subcommittees to those of other members of the House and Senate to determine whether those with the greatest influence over health care legislation and oversight were more likely to have investments in the health care industry.

Data
All members of Congress are required to file annual reports disclosing personal assets. Reports contain information about the source, type, and dollar value of assets (reported in ranges rather than exact figures). While the Office of the Clerk of the House and the Senate Office of Public Records make scanned copies of these reports available as PDFs, they do not provide aggregate data in a readily analyzable format [10,11]. However, the Center for Responsive Politics (CRP)-a nonpartisan research group that tracks the flow of money in politics-aggregates and digitizes the financial disclosure reports and makes these data publicly available [12].
We used CRP data to obtain personal financial disclosures for members of the House and Senate who submitted reports during the 11-year period from 2004 to 2014 (the most recent year available in bulk data format from CRP at the time of analysis). We identified health sector assets in the CRP data using the protocol described in S1 File. Health care-related asset categories included investments in: • health care, biotechnology, and life sciences funds; • pharmaceuticals, biologics, and chemical and molecular diagnostics; • medical devices, instruments, and supplies; • health insurance carriers and pharmacy benefit managers; • pharmacies and wholesale drug distributors; • health care services, including hospitals, ambulatory care facilities, dialysis facilities, laboratories, and physician practices; • administrative services, including health care-related information technology services, electronic health record systems, and health care consulting; • health care-related real estate, including skilled nursing facilities and long-term care facilities • miscellaneous, including contract research organizations.
We used the public member registry available at Congress.gov to determine House and Senate membership during the study period, and used committee membership lists published by the Government Publishing Office to determine committee and subcommittee membership.

Study variables
We calculated, for each year, the percentage of members holding a health care-related asset (overall, by party, and by committee); the total value of all assets and health care-related assets held; the mean, 90 th percentile winsorized mean (observations in the bottom 5th percentile are replaced with the 5 th percentile value and observations in the top 95 th percentile are replaced with the 95 th percentile value to reduce the effect of outliers), and median values of assets held per member; and the share of asset values attributable to the 9 main asset categories. For comparability of dollar values across years, we deflated all dollar amounts by the Consumer Price Index and reported all amounts in 2019 US dollars.

Methods
We conducted a descriptive analysis using summary statistics of the study variables. We also conducted graphical analyses, plotting changes of the variables over time. Legislators held assets in multiple sectors of the health care industry (Fig 3). In 2004, nearly 60% of health care-related assets held by legislators were in pharmaceuticals, biologics, and diagnostics. However, the share of health care-related assets attributable to this sector diminished in subsequent years, reaching a low point in 2011 when the sector accounted for only 20% of all health care-related assets held by members of Congress. During this time, there was a notable rise in the share of health care-related assets attributable to the health care services sector, which increased by a factor of 7 from 4% in 2004 to a high of 29% in 2011. No other sector accounted from more than 25% of health care-related assets during the study period.

Results
In both the House and Senate, members of committees and subcommittees with responsibility for health care legislation and oversight were no more likely than other members of the same chamber to hold health care-related assets.   Notably, there was significant year-to-year variation in both the prevalence and value of health care-related asset holding among members of health care-focused committees and

Discussion
From 2004-2014-a period of intensive health care legislative activity, including passage of the Affordable Care Act-over a third of all members of Congress held health care-related assets. These assets were often substantial, with a median total value per member of over $43,000. While members of health care-focused committees and subcommittees in the House and Senate did not hold health care-related assets at a higher rate than other members of their respective chambers, multiple members of these committees and subcommittees held hundreds of thousands of dollars of health care-related assets during their committee service. In short, these findings show that at the federal level, health care legislative activities were regularly conducted by lawmakers with significant financial interests in the health care industry.
This study had several limitations. First, we did not have access to current financial disclosure data for members of Congress and are therefore unable to assess trends in health carerelated asset holding beyond 2014. This limitation results from shortcomings of financial disclosure reporting. Lawmakers' disclosure forms are often filled out by hand and are published by the House and Senate as individual PDF files rather than in a searchable database. Compiling data on lawmakers' financial disclosures thus requires many hours of labor-intensive abstraction which lags behind the release of disclosure reports. Second, while we analyzed asset holdings in the health care industry, we did not analyze assets in other industries, such as the energy industry, that affect public health. Thus, our findings do not capture the full extent to which lawmakers are invested in industries that have an impact on public health. Finally, we did not analyze the relationship between lawmakers' financial holdings and their legislative activities. Although research on COI in other domains suggests that financial interests can bias professional judgment, we are unable to assess the extent to which health care-related COI might have influenced lawmakers' behavior [13,14].
For over a decade, there has been a great deal of research on the prevalence and impact of COI in medicine [15]. For the most part, however, researchers working in this area have neglected to examine the COI of health policy makers. 12 While federal legislators do not provide patient care or conduct clinical trials, they have a profound impact on the US health care system and, by extension, the health of all Americans. As such, lawmakers' health care-related COI warrant the same level of attention that has been paid to the COI of other actors in the health care system. The study highlights the value of financial disclosure data as a way to better understand the scope of health-care related COI among members of Congress. Drawing on the financial data used in this study, future research should examine the effects of lawmakers' financial interests on health care legislation and oversight.