Suppression of Renin in Diabetic Patients under Chronic Dialysis Treatment

We have seen 11 diabetic uremic patients who had long history (for 12 years on an average) of diabetes mellitus and were under long-term dialysis treatment (for 16.5 months on an average). Ten out of 11 patients had severe hypertension. In addition, 61 non-diabetic uremics and 10 non-diabetic uremics treated with β-blocker were subjected to the present study in an attempt to analyze the mechanisms of the low levels of resting (pre-dialysis) plasma renin activity (PRA) and post-dialysis PRA of the diabetic uremic patients. In diabetic uremics, resting PRA was positively correlated to the pulse pressure/diastolic blood pressure ratio, but negatively correlated to ΔPRA/removed-sodium and ΔPRA/removed-water which were very low levels in these patients. These facts indicate that the stimulation of renin release by the preceding dialysis cannot positively influence the resting PRA before the next dialysis, and that hypertension in these patients was partly related to the resting PRA. Post-dialysis PRA in diabetic uremics was significantly correlated to ΔPRA/removed-water, but not to ΔPRA/removed-sodium. The suppressed levels of post-dialysis PRA in these patients might be caused by low ΔPRA/removed-water and ineffective stimulation of sodium removal to the renin release. We suspected the possibility that the common cause of low levels of both resting and post-dialysis PRA might be partly related to the diabetic neuropathy.