Prevalence of constipation in continuous ambulatory peritoneal dialysis patients and comparison with hemodialysis patients

Abstract

Many hemodialysis patients suffer from constipation. The frequency of constipation has not been rigorously evaluated in continuous ambulatory peritoneal dialysis (CAPD) patients, however. We conducted a survey on constipation in CAPD patients and compared the findings with those in hemodialysis patients through a questionnaire. Daily dietary fiber and potassium intake were calculated from the patients' dietary records. In the questionnaire, patients were asked about bowel frequency, stool consistency, straining, and use of laxatives and resins. The frequency of constipation was 28.9% in 204 CAPD patients and 63.1% in 268 hemodialysis patients. The hemodialysis patients had a 3.14 times higher relative risk of constipation than the CAPD patients. Only 3.4% of CAPD patients needed resin to avoid hyperkalemia. Of hemodialysis patients, 49% needed resin. Among the 261 hemodialysis patients, 205 (78.5%) suppressed an urge to defecate during hemodialysis therapy. Potassium and total dietary fiber intake per day were 1.8 +/- 0.5 g and 11.0 +/- 4.0 g in CAPD patients, which were higher (P < 0.01) than the values in hemodialysis patients--1.3 +/- 0.5 g and 5.9 +/- 2.7 g. The results suggest that constipation occurs less frequently in CAPD patients than in hemodialysis patients. The low rate of constipating drug administration, dialysis modality-based lifestyle, and higher total dietary fiber intake may cause the lower prevalence of constipation in CAPD patients.