Frailty Status Predicts Urinary Tract Infection Risk Following Kidney Transplant

Urinary tract infections (UTIs) are the most common infectious complication in kidney transplant (KT) recipients. UTI risk is associated with frailty in older adults, and UTIs may exacerbate frailty. However, this relationship has not been described in KT recipients who are at both greater risk of frailty and UTIs.

We conducted a retrospective chart review of 90 KT recipients aged ≥ 50 years who underwent KT between January and July 2021 and had ≥ 12 months of post-transplant follow-up. UTIs were identified at the time of each occurrence. Frailty was assessed at baseline using the modified Rockwood-20 frailty index (mFI); scores ≥ 0.25 were considered frail, 0.08-0.24 pre-frail, and < 0.08 non-frail. The primary outcome was cumulative UTI occurrence based on frailty status, analyzed using Cox proportional hazards regression.

Among 90 KT recipients, 33 (37%) developed ≥ 1 UTI. Notably, 45% of KT recipients with UTIs were frail, compared to 25% of KT recipients without UTIs. Compared to non-frail KT recipients, frail KT recipients had a significantly higher risk of UTIs (HR 8.13, 95% CI 1.89, 34.91; p = 0.005), as did pre-frail KT recipients (HR 4.51, 95% CI 1.02, 19.92; p = 0.047). Frail KT recipients also experienced earlier UTI onset, with 12 out of 21 total UTIs (57%) occurring within the first 30 days post-KT.

Frailty and prefrailty are associated with increased UTI risk in KT recipients. These findings highlight the importance of frailty assessment in post-transplant care and suggest the need for targeted interventions to reduce UTI risk in this vulnerable population.