1935: Sex-associated disparities in industry payments to US authors in high-impact rheumatology journals correlate with author impact

Background/Purpose: To assess sex-associated disparities in industry payments to US physician-authors in high-impact rheumatology journals and their correlation with author impact.

Methods: US authors of publications in four high-impact rheumatology journals (January-June 2023 issues of Lancet Rheumatol, Nat Rev Rheum, Ann Rheum Dis, Arthritis Rheumatol) were vetted on Open Payments Database (OPD) for industry payments (2017-2021). The h-index (an accepted metric of author impact) and dollar amounts were recorded. Differences in the percentages of male vs female US authors with or without OPD entries, in research-associated and non-research-associated payments, and in h-indexes were determined. Two hematology, two surgery, and two obstetrics/gynecology (ob/gyn) high-impact journals were similarly vetted.

Results: We vetted 296 publications in the rheumatology journals. Of the 712 (356M + 356F) discrete US physician-authors, 150 (42.1%) men and 112 (31.5%) women received ≥1 industry payment (p = 0.003). Total, non-research-associated, and research-associated industry payments to the 150 men than to the 112 women (p ≤ 0.022). Male US physician-authors of publications in hematology, surgery, and ob/gyn journals also received greater payments than did corresponding female US physician-authors (Table I), with the disparities being numerically greater for rheumatology than for the other disciplines (Fig 1A).

The h-indexes of the men in each journal-discipline were also greater than those of the corresponding women (p < 0.001; Fig 1B). Plots of industry payments vs h-index revealed the regression lines for the women to be lower than those for the men at low h-indexes but to catch up and overtake at higher h-indexes (Fig 2A). Of note, at the female h-index 90^th percentiles for the individual journal-disciplines, total, non-research-associated, and research-associated payments were all numerically greater to the women than to the men only in rheumatology. In contrast, the respective payments in hematology and surgery remained numerically greater to the men than to the women, with the payments to the men and women being similar in ob/gyn (Fig 2B). This suggests that, especially in rheumatology, author impact is an important contributory factor to the magnitude of industry payments.

Conclusion: Significant differences exist in industry payments and h-indexes between male and female US physician-authors of publications in high-impact journals, especially high-impact rheumatology journals. The correlation between industry payments and h-index suggests that the greater payments to men than to women are not a conscious preference by the pharmaceutical industry for men per se but rather reflects industry’s preference for physicians, male or female, with “stature” (high author impact). Nonetheless, differential industry payments to male vs female authors may have unknown ramifications for the types of studies executed and the experimental approaches taken. Additional studies are warranted to elucidate the root causes for the differences in author impact between men and women and how they lead to differential industry payments to men vs women.