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Abstract: FR-PO159

FGF-23 and Cause-Specific Mortality in Community-Living Individuals (Health ABC Study)

Session Information

Category: Bone and Mineral Metabolism

  • 402 Bone and Mineral Metabolism: Clinical

Authors

  • Sharma, Shilpa, UCLA, Los angeles, California, United States
  • Katz, Ronit, University of Washington, Seattle, Washington, United States
  • Drew, David A., Tufts Medical Center, Boston, Massachusetts, United States
  • Gutierrez, Orlando M., UAB School of Medicine, Birmingham, Alabama, United States
  • Shlipak, Michael, San Francisco VA Medical Center, San Francisco, California, United States
  • Sarnak, Mark J., Tufts Medical Center, Boston, Massachusetts, United States
  • Ix, Joachim H., UCSD, San Diego, California, United States
Background

FGF23 is a protein that was initially identified as a key regulator of phosphorus and vitamin D metabolism. Elevated concentrations of FGF23 are associated with poor clinical outcomes in different patient populations, but cause-specific mortality is under-studied.

Methods

Among 2763 healthy community-living older adults who participated in the Health, Aging, and Body Composition (Health ABC) study, plasma intact FGF23 levels were measured from samples drawn in 2000 and 2001, and participants were followed through 2012. Mortality was adjudicated by a reviewing committee. Associations of FGF23 with total and cause specific mortality were evaluated using Cox proportional hazards models.

Results

At baseline, the mean age was 75 (±3) years old, 40% were black, and 55% were women. Median FGF23 was 47 (IQR 37, 60) pg/ml and was inversely correlated with eGFR (rs= -0.260). During 8.3 years (median) follow-up, there were 821 deaths. In the multivariable Cox PH regression analysis (Table), each two-fold higher concentration of plasma FGF23 was associated with all-cause mortality and cardiovascular, gastrointestinal bleed, and kidney failure deaths, but not with cancer, dementia, sepsis or pulmonary related deaths.

Conclusion

Although high FGF23 concentrations are associated with total mortality, the association appears restricted to certain death types. Future studies are needed to evaluate potential mechanisms linking FGF23 concentrations with specific causes of death.

Association of (intact) FGF23 and Cause Specific Mortality
Cause of MortalityEventsFGF23 (per doubling)
Hazard Ratio (95% CI)*
GI bleed82.54 (1.02, 6.32)
Renal Failure241.58 (1.05, 2.38)
Cardiovascular 3091.35 (1.16, 1.56)
Pulmonary 401.34 (0.86, 2.08)
All-Cause8211.26 (1.15, 1.39)
Cancer2451.01 (0.83, 1.23)
Dementia560.82 (0.54, 1.25)
Sepsis15
0.70 (0.33, 1.48)

*Adjusted for age, gender, race, site, education, diabetes, systolic blood pressure, hypertension meds, body mass index, smoking, prevalent cardiovascular disease, serum albumin, c-reactive protein, estimated glomerular filtration rate and urine albumin creatinine ratio

Funding

  • NIDDK Support