The goal of this study is to estimate risk of post-donation healthcare use attributable to informal caregiving among obese living donors. Improving our understanding of the relationship between caregiving, donation, and healthcare use will allow us to improve living donor informed consent and post-donation care, particularly among older donors and those of minority race/ethnicity.

Caregiver burden is a well-known issue of primary caregiving for individuals with chronic disease, including transplant candidates and recipients. Informal caregiving is associated with an estimated $306 billion in unpaid labor costs and an average of $7,000 in out-of-pocket expenses related to the caregiving role. In addition to financial burdens, caregivers experience psychological distress and adverse health outcomes, including higher rates of hypertension and heart disease. These burdens differ by caregiver ethnicity, age, and rurality. Ethnic minority caregivers have reported more depression, lower use of support services, and worse physical health than Whites. African American caregivers report lower levels of depression but worse physical health. Caregiver age also plays a role in physical health burden, with older caregiver age shown to be negatively associated with caregiver physical functioning, bodily pain, vitality, and general health perception. This association is directly relevant to living kidney donation, as the prevalence of donors who are 65 years or older has increased from < 1% in 1998 to 5.6% in 2019 (based on OPTN data as of 3/23/2020). Rural caregivers report greater financial burden than their urban counterparts, of particular concern in the Deep South, where nearly two-thirds of all counties are rural.

When caregivers have their own underlying health issues, such as obesity, burdens may be further magnified when the caregiver becomes a patient, simultaneously requiring their own care while caring for another (e.g. obese living kidney donors who are the primary caregiver for their transplant recipient). Approximately 20% of living kidney donors are parents and significant others, individuals who often serve as the recipient's primary caregiver. Moreover, obese donors are at higher risk of post-donation disease development, including end-stage renal disease, diabetes, and hypertension. As donor selection criteria have expanded to include more obese individuals, these burdens impact high volume transplant centers in the Deep South that serve largely minority and rural populations. Comorbidity, such as obesity, in caregiver donors may increase the need for healthcare utilization, further exacerbating financial burdens, interfering with caregiver responsibilities, and subsequently impacting the recipient's health outcomes. To date, it is unknown whether the burdens of being an obese caregiver living donor are associated with healthcare utilization post-donation compared to non-caregivers and whether donor age, race, and rurality modify this relationship. This study is ancillary to an NIH-funded retrospective cohort study of living kidney donors with obesity (1R01DK113980) and will leverage the infrastructure of this R01 to explore the primary exposure of caregiving within this cohort.

Inclusion Criteria:

• Age 18 years or greater
• Underwent living donor nephrectomy at a transplant center in the United States between 1968 to present
• Obesity: had a body mass index of 30 kg/m2 or greater at time of kidney donation

Exclusion Criteria:

• Age < 18 years
• Non-obese at time of donation
• Does not consent to study participation

This study is an ancillary study to 1R01DK113980, a retrospective cohort study that is assembling the largest cohort of previous living kidney donors with obesity from 1968-present from all centers across the US. The parent R01 is projected to enroll approximately 25,000 obese living donors, and 20% (n=5,070) of these are estimated to have served as the primary caregiver for their transplant recipient (the primary exposure of this study).

To be determined

These numbers correspond to the individuals who completed survey measures during the study period and indicated whether or not they were the primary caregiver for their transplant recipient.

44 months

This was a retrospective survey, and as such, the only potential risk was accidental breach of confidentiality. No adverse events occurred.