Low or high birth weight is associated with CKD only in men

Li S et al. (2008) Low birth weight is associated with chronic kidney disease only in men. Kidney Int 73: 637–642

An association between low birth weight and increased risk of chronic kidney disease (CKD) in adulthood has been suggested by several studies. To investigate this association in a more geographically and ethnically diverse population than those previously studied, Li et al. analyzed adults who were screened for CKD during the period August 2000 to December 2005 as part of the US National Kidney Foundation's Kidney Early Evaluation Program.

In all, 12,364 participants (28.7% African American, 76.4% female, mean age 49.1 years, mean self-reported birth weight 3,195 g) with a history of diabetes or hypertension, or a family history of diabetes, hypertension or kidney disease, were divided into sex-specific quintiles according to birth weight. A significant association between birth weight and CKD (defined as an estimated glomerular filtration rate <60 ml/min/1.73 m², or a urinary albumin:creatinine ratio ≥30 mg/g) was seen in white men (P = 0.0012), but not in women of any race. Men who had either a low birth weight (<2,500 g; 11.1%) or a high birth weight (≥4,500 g; 11.9%) were at a higher risk of developing CKD than were those who had a normal birth weight (3,000–3,999 g; 49.4%; adjusted odds ratios 1.65, 95% CI 1.24–2.20 and 1.41, 95% CI 1.06–1.88, respectively).

The authors hypothesize that the influence of gender on the association between birth weight and CKD might be explained by a renoprotective effect of estrogen.