Peritoneal Dialysis and the Diabetic Patient

The diabetic patient with ESRD presents many therapeutic challenges, some of which are particularly difficult when PD is selected as RRT. Serlie et al. reported lower transcapillary ultrafiltration (TCUF) among diabetic patients compared with non-diabetics, matched for age, sex and duration of CAPD, shortly after initiation of PD¹.  However, no significant difference was observed one year later.  These results suggest that long-term exposure to high glucose concentrations in diabetics prior to CAPD may cause changes in the capillary wall aquaporins, similar to those observed after prolonged exposure to high glucose concentration. These findings may explain the published discrepancies on the presence or absence of increased peritoneal permeability among diabetic patients.  It is possible that differences were observed when diabetics were compared to non-diabetics early in the course of the disease, but not after many years of therapy when both groups could have had abnormally high permeability.

 

Diabetic patients often develop fluid overload for reasons other than poor UF.  A significant number of diabetic patients are nephrotic at the time of initiation of dialysis.  Even if their peritoneal UF is satisfactory, they have difficulty in mobilizing fluid from the interstitial compartment due to low oncotic pressure.

 

Abnormally high leakage of albumin across capillary walls is characteristic of diabetic microvascular disease.  This increase in capillary permeability is not confined to the renal or retinal capillaries and has been documented in the peritoneal capillaries as well¹.  Shostak and Gotloib have demonstrated increased permeability in the peritoneal capillaries of diabetic rats and Krediet et al. have made similar observations in humans^1-3.  This decreased permselectivity may be due to a reduction in the fixed negative charges of the capillary basement membrane^2,3.

The potential clinical consequences of high peritoneal permeability are obvious in view of the well recognized correlation between high peritoneal transport and morbidity and mortality^4-6.  High peritoneal transport inversely correlates with serum albumin concentration (SAC).  SAC is a powerful marker of mortality⁷.  Nakamoto et al. have confirmed that high peritoneal membrane transport and protein permeability are higher among diabetic patients undergoing PD⁸.  The authors attributed the hypoproteinemia observed among their diabetic patients to the higher permeability of the membrane to protein.  Others have reported that DM is significantly more frequent among high transporters and is less frequently associated with low transport⁹.  In the univariate analysis, high peritoneal transport rate, DM, low serum creatinine, low albumin and older age significantly predicted mortality.  However, in the multivariate analysis, only DM, low serum creatinine and high peritoneal transport rate were shown as mortality risk factors.  Among non-diabetics, high transport did not affect survival.  The most important risk factor was DM rather than high peritoneal transport.  No difference in peritoneal transport was observed between type I and type II diabetic patients matched for gender, duration of PD and clinical characteristics¹⁰.

 

Potential Benefits of PD in the Treatment of the Diabetic Patient

 

Potential Disadvantages of PD for Diabetic ESRD Patients

 

When to Initiate PD in the Diabetic Patient

 

PD Prescriptions for Diabetics

 

Glycemic Control of the PD Patient

 

 

References:

1. Serlie MJM, Struijk DG, de Blok K, Krediet RT Differences in fluid and solute transport between diabetic and nondiabetic patients at the onset of CAPD. Adv Perit Dial 13: 29-32, 1997
2. Shostak A, Gotloib L. Increased peritoneal permeability to albumin in streptozotocin diabetic rats. Kidney Int 49:705-714, 1996
3. Krediet RT, Zuyderhoudt FMJ, Boeschoten EW, Arisz L. Peritoneal permeability to proteins in diabetic and non_diabetic continuous ambulatory peritoneal dialysis patients. Nephron 1986;42:133-140, 1986
4. Selgas R, Bajo MA, Fernandez-Reyes MJ, Bosque E, Lopez-Revuelta K, Jimenez C, Borrego F, de Alvaro F. An analysis of adequacy of dialysis in a selected population on CAPD for over 3 years: the influence of urea and creatinine kinetics. Nephrol Dial Transplant 8:1244-1253, 1993
5. Churchill DN, Thorpe KE, Nolph KD, Keshaviah PR, Pagé D, Oreopoulos DG, for the Canada-USA (CANUSA) Peritoneal Dialysis Study Group. Increased peritoneal membrane transport is associated with decreased CAPD technique and patient survival. J Am Soc Nephrol 8:189A, 1997
6. Fried L. Higher membrane permeability predicts poorer patient survival. Perit Dial Int 17:387-389, 1997
7. Lowrie EG, Huang WH, Lew NL. Death risk predictors among peritoneal dialysis and hemodialysis patients:  A preliminary comparison. Am J Kidney Dis 26:220-228, 1995
8. Nakamoto H, Imai H, Kawanishi H, Nakamoto M, Minakuchi J, Kumon S, Watanabe S, Shiohira Y, Ishii T, Kawahara T, Tsuzaki K, Suzuki H: Effect of diabetes on peritoneal function assessed by personal dialysis capacity test in patients undergoing CAPD. Am J Kidney Dis 40:1045-1054, 2002
9. Cueto-Manzano AM, Correa-Rotter R: Is high peritoneal transport rate an independent risk factor for CAPD mortality? Kidney Int 57:314-320, 2000
10. Lin JJ, Wadhwa NK, Suh H, Cabralda T.  Comparisons of peritoneal transport between insulin-dependent and noninsulin-dependent diabetic peritoneal dialysis patients. Perit Dial Int 17:208-209, 1997