Increased soluble Tumour Necrosis Factor-alpha receptors (sTNF-aR) 1 and 2 have been associated with Diabetic Kidney Disease (DKD) in type 1 and type 2 diabetes1 2 . Whether this applies to prgnancy is not known. We measured serial levels of sTNF-aR1 and 2 (R1+R2) pre, during 2nd trimester (T2) and post pregnancy in healthy women and women with pre-existing diabetes using the Multiplex immunoassay.
At baseline, estimated glomerular filtration rate was > 90ml/min/1.72m2 in all but one case. The baseline 24 hour albumin excretion rate for diabetics and controls at baseline was [17.08±8.31] and [5.31 ±1.91] µg/min (p=0.25).
Data for the study group as a whole are shown in the figure. There was 73% of type 1 compared to 27% of type 2 diabetes participants. Using serial comparison within subjects, in the diabetes group (N=8) there was a significant increase in both R1+R2 from baseline to T2 (p =0.01). This did not return to pre-pregnancy values post partum (p> 0.05) (Figure), in contrast to controls where there was a significant reduction of both TNF-aR1 (N=3) and TNF-aR2 (n=4) from T2 to post-partum. There was no significant difference in changes in R1 and R2 in type 1 compared with type 2 diabetes.
Whether the failure of sTNFRs to return to pre-pregnancy levels post partum is linked to early DKD as reflected by microalbuminuria or the persisting effects of hyperfiltration of pregnancy requires further studies.