Fractures and Subsequent Graft Loss and Mortality among Older Kidney Transplant Recipients

Abstract

OBJECTIVES Older adults who undergo kidney transplantation (KT) are living longer with a functioning graft and are at risk for age‐related adverse events including fractures. Understanding recipient, transplant, and donor factors and the outcomes associated with fractures may help identify older KT recipients at increased risk. We determined incidence of hip, vertebral, and extremity fractures; assessed factors associated with incident fractures; and estimated associations between fractures and subsequent death‐censored graft loss (DCGL) and mortality. DESIGN This was a prospective cohort study of patients who underwent their first KT between January 1, 1999, and December 31, 2014. SETTING We linked data from the Scientific Registry of Transplant Recipients to Medicare claims through the US Renal Data System. PARTICIPANTS The analytic population included 47 815 KT recipients aged 55 years or older. MEASUREMENTS We assessed the cumulative incidence of and factors associated with post‐KT fractures (hip, vertebral, or extremity) using competing risks models. We estimated risk of DCGL and mortality after fracture using adjusted Cox proportional hazards models. RESULTS The 5‐year incidence of post‐KT hip, vertebral, and extremity fracture for those aged 65 to 69 years was 2.2%, 1.0%, and 1.7%, respectively. Increasing age was associated with higher hip (adjusted hazard ratio [aHR] = 1.37 per 5‐y increase; 95% confidence interval [CI] = 1.30‐1.45) and vertebral (aHR = 1.31; 95% CI = 1.20‐1.42) but not extremity (aHR = .97; 95% CI = .91‐1.04) fracture risk. DCGL risk was higher after hip (aHR = 1.34; 95% CI = 1.12‐1.60) and extremity (aHR = 1.30; 95% CI = 1.08‐1.57) fracture. Mortality risk was higher after hip (aHR = 2.31; 95% CI = 2.11‐2.52), vertebral (aHR = 2.80; 95% CI = 2.44‐3.21), and extremity (aHR = 1.85; 95% CI = 1.64‐2.10) fracture. CONCLUSION Our findings suggest that older KT recipients are at higher risk for hip and vertebral fracture but not extremity fracture; and those with hip, vertebral, or extremity fracture are more likely to experience subsequent graft loss or mortality. These findings underscore that different fracture types may have different underlying etiologies and risks, and they should be approached accordingly. J Am Geriatr Soc 67:1680–1688, 2019

Bone and Mineral Disease in Kidney Transplant Recipients

“…Our approach is to consider a full clinical risk factor assessment for osteoporosis and fractures. Risk factors for post-transplant osteoporosis and fractures can be divided into pre- and post-transplant factors (2,4,31,32,42,43) (Figure 1). Measurement of BMD by dual energy x-ray absorptiometry is the clinical gold standard to assess fracture risk.…”

Frailty and Long-Term Post-Kidney Transplant Outcomes

“…Compared to community-dwelling older adults, older KT recipients are at elevated risk of age-related outcomes including early hospital readmission, dementia, Alzheimer's disease, infections, malignancy and fractures (2)(3)(4)(5)(6). For example, we recently found that the 10-year risk of post-KT dementia was 17.0% for KT recipients aged 75 years and older; this is a much higher proportion than the estimated 7.5% risk for community-dwelling older adults of the same ages (7).…”

Natural History of Bone Disease following Kidney Transplantation

“…Fracture risk is increased after kidney transplantation, particularly in the early post-transplant period 1 – 3 . With the increasing age and longevity of kidney transplant recipients, 4 improving long-term quality of life is imperative, which includes the prevention of osteoporosis and fractures 5 …”

“…[1][2][3] With the increasing age and longevity of kidney transplant recipients, 4 improving longterm quality of life is imperative, which includes the prevention of osteoporosis and fractures. 5 The implementation of steroid-minimization protocols has reduced bone loss and fracture rates post-transplant. [6][7][8] Consequently, the evolution of bone mineral density (BMD) in contemporary kidney transplant recipients appears overall neutral, with limited bone loss at the central skeleton.…”