Is skin autofluorescence a marker of metabolic memory in pregnant women with diabetes?

Aim To determine whether skin autofluorescence can help to detect those who have previously had abnormal glucose levels among women referred for diabetes during pregnancy. Methods Using an advanced glycation end product reader (AGE Readertm; DiagnOptics BV, Groningen, the Netherlands), we measured forearm skin autofluorescence at 24–30 weeks of gestation in all women who were referred to our Nutrition Diabetology unit for diabetes during pregnancy. Results The study included 230 women (200 with gestational diabetes and 30 with pre-gestational diabetes, of whom 21 had Type 1 and nine had Type 2 diabetes) and a reference group of 22 normoglycaemic non-pregnant women. Skin autofluorescence was significantly higher in women with pre-gestational diabetes (1.97 ± 0.44 arbitary units) compared with gestational diabetes (1.77 ± 0.32 arbitary units; P = 0.003) and lower in the reference group (1.60 ± 0.32 arbitary units; P = 0.009 vs all pregnant women). Among women with gestational diabetes, 71 had a history of hyperglycaemia (i.e. gestational diabetes or macrosomia in a previous pregnancy or discovery of diabetes before 24th gestational week in the present pregnancy). These women had higher levels of skin autofluorescence (1.83 ± 0.35 arbitary units) than women with gestational diabetes without previous history of hyperglycaemia (1.73 ± 0.30 arbitary units; P = 0.04, non-significant, adjusted for age). Skin autofluorescence increased with the number of criteria present for previous hyperglycaemia (P for trend = 0.008) and was significantly associated with having two or three criteria for hyperglycaemia after adjusting for age (P = 0.02). Conclusions Skin autofluorescence could reflect previous long-term hyperglycaemia in pregnant women, and could therefore be a marker of metabolic memory.