Gender Disparities in Kidney Transplantation Referral Vary by Age and Race: A Multiregional Cohort Study in the Southeast United States

Abstract

Introduction: Men (vs. women) are more likely to be waitlisted or receive a kidney transplant. Whether gender disparities exist in earlier transplant steps (i.e., referral) and whether age, race, or obesity factors play a role are unknown.

Methods: Adults (18-80 years; N = 45,015) initiating dialysis in Georgia (GA), North Carolina (NC), or South Carolina (SC) (2012-2016) from the United States Renal Data System were linked to the Early Transplant Access Registry, with follow-up to December 2017. Using a mixed-effects logistic regression model adjusted for several patient characteristics, we assessed the association between gender and referral within 12 months, including interaction terms for age, race/ethnicity, and obesity.

Results: Overall, 37.0% and 41.5% of women and men, respectively, were referred within 12 months. In fully adjusted models, women (vs. men) were 14% less likely to be referred (odds ratio [OR]: 0.86; 95% CI: 0.82-0.90). Women (vs. men) aged 45 to 64 years and 65 to 80 years were 0.93 (0.87-0.99) and 0.72 (0.66-0.77) less likely to be referred, respectively. Women (vs. men) of non-Hispanic White and non-Hispanic Black race were 0.76 (0.71-0.82) and 0.93 (0.88-0.99) less likely to be referred, respectively. For other race (Hispanic, other) and age (18-44 years) subgroups, and all obesity subgroups, no gender differences in referral rates were observed.

Conclusion: In the Southeast, women are less likely to be referred for a transplant, and this disparity is specific to older non-Hispanic Black and White women. These findings have important implications for known gender disparities in upstream (i.e., waitlisting) transplant steps and in the design of interventions to reduce gender disparities in transplant.

Keywords: epidemiology; gender disparities; health services research; kidney transplant; transplant referral.

Graphical abstract

Figure 1

Flow diagram of study inclusion and exclusion criteria for study population. BMI, body mass index; GA, Georgia; ID, identification; NC, North Carolina; SC, South Carolina; USRDS, United States Renal Data System.

Figure 2

Association between gender and 12-month referral by (a) age and (b) race/ethnicity. The reference line of 1 (dotted line) indicates no difference in referral rates between men and women.