Abstract: SA-PO005

Obesity and Recovery from AKI: An Observational Feasibility Study

Session Information

Category: Acute Kidney Injury

  • 003 AKI: Clinical and Translational

Authors

  • MacLaughlin, Helen L., King's College Hospital, London, United Kingdom
  • Pot, Gerda K, King's College London, London, United Kingdom
  • Macdougall, Iain C., King's College Hospital, London, United Kingdom
  • McIntyre, Christopher W., London Health Sciences Centre, London, Ontario, Canada
  • Selby, Nicholas M., University of Nottingham, Derby, United Kingdom
Background

Acute kidney injury (AKI) occurs in 〉5% of hospital admission in the UK, and is associated with an increased risk of developing or worsening chronic kidney disease (CKD). The effect of obesity on recovery of kidney function after AKI, and the combined risk of obesity and AKI on subsequent development of CKD is not known.

Methods

A study was conducted to determine the feasibility of recruitment, retention and data collection procedures for the planned Ob-AKI cohort study in a sample of 100 patients hospitalised with an episode of AKI. Feasibility outcomes for recruitment, retention and trends in exploratory measures of recovery from AKI (〉75% of preAKI eGFR) and development/progression of CKD (decrease in eGFR of ≥25% + rise in CKD category) were examined by BMI (〈25, 25-29.9, 30+) over 12 months. Potential participants were identified by referral and electronic detection of episodes of AKI during hospital admissions. Inclusion criteria were 18-85 years, episode of AKI (KDIGO 2012), and pre AKI creatinine measured within the previous 12 months.

Results

41% of eligible patients consented to participate in the study, exceeding the feasibility target of 15%. 101 patients were recruited to the study (67M, 34F, mean age 63.5 (±12.6) years and mean BMI 29.9kg/m2, range 18.1 to 54.3kg/m2); 28.3% with stage 1, 21.2% stage 2 and 50.5% stage 3 AKI. Retention was 86% at 6 months and 80% at 12 months; there were 10 deaths and 3 patients commenced dialysis during the study. There may be an interaction between obesity, pre-existing CKD and renal function after AKI. In obese patients with pre-existing CKD, recovery of kidney function at 6 months may be higher with subsequently greater progression at 12 months, compared to patients with normal BMI with CKD (71% (10/14) vs 61% (8/13)) and (31% (5/16) vs 27% (3/11)) respectively. Conversely, obese patients without CKD at baseline may have lower renal recovery at 6 months (35% (8/17) vs 47% (6/17)), yet develop less CKD at 12 months (37% (6/16) vs 69% (9/13)), compared to patients with normal BMI.

Conclusion

We have demonstrated that it is feasible to perform long term observational studies addressing AKI outcomes associated with obesity. A fully powered prospective cohort study to examine the relationships between obesity and outcomes afrer AKI is warranted.

Funding

  • Government Support - Non-U.S.