Low Birth Weight and Risk of Proteinuria in Former Kidney Donors
Department of Medicine, University of Minnesota, Minneapolis, MN
Meeting: 2013 American Transplant Congress
Abstract number: B924
Introduction:
Low birth weight (LBW) has been linked to hypertension, diabetes, and possibly CKD. We hypothesized that kidney donors with LBW may be at increased risk of hypertension, proteinuria, or reduced GFR beyond what is typically seen after uninephrectomy.
Methods:
255 of 3698 donors who donated between 1963 and 2007 were randomly selected for iohexol GFR, albumin excretion, and prevalence of hypertension. We contacted these donors by phone to ascertain their self-reported birth weights. Self-report of birth weight is within 4 oz in 25% of people; inaccurate in 28% and unknown in the remaining. We examined the predictors of iohexol GFR <60 ml/min/1.73m2, iohexol GFR < 45 ml/min/1.73m2, albuminuria and hypertension. Predictors examined included age at GFR measurement, time since donation, BMI, sex, serum creatinine level, SBP and DBP, race and birth weight.
Results:
188 of 255 donors provided birth weights; 17 of those had low birth weight (<2.5 kg). Those who provided birth weights were younger at time of GFR measurement (51.8±9.3 vs. 55.8±10.4 years, p=0.004) had lower systolic (120.5±13.7 vs. 126.5±15.8 mmHg, p=0.004) and diastolic blood pressure (72.3±8.7 vs. 75.2±9.2 mmHg, p=0.26). They did not vary significantly with respect to other characteristics.
LBW was not associated with mGFR <45 or 60 or hypertension but was associated with albuminuria. Main results are shown in table.
| Outcome Covariates | Odds Ratio (95% CI) | P- Value |
|---|---|---|
| mGFR <60 ml/min/1.73m2 | ||
| Age at GFR (years) | 1.13 (1.08, 1.19) | <.001 |
| Time from Donation (years) | 0.91 (0.86, 0.97) | 0.002 |
| BMI | 1.11 (1.03, 1.21) | 0.010 |
| Female | 4.24 (1.65, 10.93) | 0.003 |
| mGFR <45 ml/min/1.73m2 | ||
| DBP (mmHg) | 0.87 (0.76, 1.00) | 0.046 |
| Albuminuria | ||
| BMI | 1.13 (1.03, 1.24) | 0.008 |
| SBP (mmHg) | 1.04 (1.01, 1.08) | 0.018 |
| Birth Weight (kg) | 0.44 (0.19, 1.00) | 0.050 |
| Hypertension | ||
| Age at GFR (years) | 1.09 (1.05, 1.13) | <.001 |
| BMI | 1.13 (1.05, 1.20) | <.001 |
| Serum Creatinine (at donation) | 0.07 (0.01, 0.82) | 0.035 |
Also shown is a depiction birth weight vs. ACR.
Conclusion:
Kidney donors with LBW may be at higher risk for albuminuria. Further and larger studies are warranted to verify if birth weight is indeed associated with this risk and whether it translates into kidney disease.
To cite this abstract in AMA style:
MacDonald D, Jackson S, Kukla A, Spong R, Issa N, Matas A, Ibrahim H. Low Birth Weight and Risk of Proteinuria in Former Kidney Donors [abstract]. Am J Transplant. 2013; 13 (suppl 5). https://atcmeetingabstracts.com/abstract/low-birth-weight-and-risk-of-proteinuria-in-former-kidney-donors/. Accessed June 7, 2025.« Back to 2013 American Transplant Congress