Abstract: FR-PO500

Consistency of the Obesity Paradox across Different Stages of CKD in Over 2 Million Veterans

Session Information

Category: Chronic Kidney Disease (Non-Dialysis)

  • 304 CKD: Epidemiology, Outcomes - Non-Cardiovascular

Authors

  • Soohoo, Melissa, UC Irvine, Orange, California, United States
  • Streja, Elani, UC Irvine, Orange, California, United States
  • Obi, Yoshitsugu, UC Irvine, Orange, California, United States
  • Rhee, Connie, UC Irvine, Orange, California, United States
  • Park, Christina, UC Irvine, Orange, California, United States
  • Moradi, Hamid, UC Irvine, Orange, California, United States
  • Kovesdy, Csaba P., University of Tennessee Health Science Center, Memphis, Tennessee, United States
  • Kalantar-Zadeh, Kamyar, UC Irvine, Orange, California, United States
Background

The inverse relationship between body mass index (BMI) and mortality, also known as the “obesity paradox”, has been described for both dialysis and non-dialysis dependent CKD patients. However, the relationship of BMI with mortality across all increasing CKD stages (including early CKD), is less well-known.

Methods

We investigated a cohort of 2.1 million US veterans with a BMI measurement between 2005-2006. CKD stages were created according to eGFR (estimated glomerular filtration rate) at the time of BMI measurement. Using Cox models adjusted for age, gender, race and diabetes status, we examined the relationship of BMI with all-cause mortality across strata of CKD stage.

Results

Patients were 64±14 years old, 5% female, 15% African-American, and 36% diabetic with a mean±SD baseline BMI 29±6 kg/m2 and median[IQR] eGFR 75[61, 91] mL/min/1.73m2. Patients were followed for a median[IQR] follow-up of 10.6[6.9, 11.1] years. We observed a reverse J-shaped association across all CKD stages compared to the referent BMI 25-<30 kg/m2, where BMI≥40 kg/m2 was associated with a higher risk of mortality across all CKD strata, except for CKD Stage 5 patients [HR(95%CI): 1.00[0.90, 1.12]. The relationship of BMI≥40 kg/m2 with mortality incrementally declined towards the null across worsening kidney stages. However, across all stages of CKD, BMI<25 kg/m2 was persistently associated with the highest risk of mortality. [Figure]

Conclusion

The relationship of morbid obesity with a higher risk of mortality in US veterans attenuates across worsening CKD stages, further supporting the notion of an “obesity paradox”. Further studies are needed to understand the underlying mechanism of this relationship and whether weight management strategies are indicated in patients with worsening kidney disease.

Funding

  • NIDDK Support