Influence of sex on hyperfiltration in patients with uncomplicated type 1 diabetes.

The aim of this analysis was to examine sex-based differences in renal segmental resistances in healthy controls (HCs) and patients with type 1 diabetes (T1D). We hypothesized that hyperfiltration-an early hemodynamic abnormality associated with diabetic nephropathy-would disproportionately affect women with T1D, thereby attenuating protection against the development of renal complications. Glomerular hemodynamic parameters were evaluated in HC ( = 30) and in normotensive, normoalbuminuric patients with T1D and either baseline normofiltration [ = 36, T1D-N, glomerular filtration rate (GFR) 90-134 ml·min·1.73 m] or hyperfiltration ( = 32, T1D-H, GFR ≥ 135 ml·min·1.73 m) during euglycemic conditions (4-6 mmol/l). Gomez's equations were used to derive efferent (R) and afferent (R) arteriolar resistances, glomerular hydrostatic pressure (P) from inulin (GFR) and paraaminohippurate [effective renal plasma flow (ERPF)] clearances, plasma protein and estimated ultrafiltration coefficients (K). Female patients with T1D with hyperfiltration (T1D-H) had higher R (1,985 ± 487 vs. 1,381 ± 296 dyne·sec·cm, < 0.001) and filtration fraction (FF, 0.20 ± 0.047 vs. 0.16 ± 0.03 < 0.05) and lower ERPF (876 ± 245 vs. 1,111 ± 298 134 ml·min·1.73 m < 0.05) compared with male T1D-H patients. Overall, T1D-H patients had higher P and lower R vs. HC subjects, although there were no sex-based differences. In conclusion, female T1D-H patients had higher R and FF and lower ERPF than their male counterparts with no associated sex differences in R Prospective intervention studies should consider sex as a modifier of renal hemodynamic responses to renal protective therapies.