Comparison Of Thyroid Function Tests In Peritoneal Dialysis and Hemodialysis

It has been shown that Continuous ambulatory peritoneal dialysis (CAPD) changes serum protein levels, and can lead to changes in thyroid function tests (TFTs). At present limited literature is available regarding this topic the aim of this study therefore was to compare the TFTs results of CAPD and HD patients with those of a control grop. In a case control study, 24 CAPDs,36 HDs and 36 controls were randomly selected from among individuals who had undergone at least 3 months of dialysis, and had no history of thyroid disorders or related drug use, which could influence the TFTs. Fasting samples were collected between changes of peritoneal dialysis fluid, and just before initiating of hemodialysis and heparin injections. The TT4, TT3, FT4, FT3, TBG (RIA), TSH(IRMA), were measured. Data presented as Mean±SE and Median, IQ75-25 range. Data were analyzed by ANOVA, Post hoc test (Tukey test) and KruskalWallis using SPSS 10 software. The mean ages of participants in the CAPD, HD and normal groups were (51±3), (54±3) and (40±2) years, respectively. The means for TT4 in CAPD, HD and normal subjects were (6.6±0.3), (6.6±0.2) and (8.8±0.3) µgr/dl, respectively (p<0.0001). The TT4 mean was lower in CAPD and HD than in normal subjects (p<0.01). The means of TT3 in CAPD, HD and normal subjects were (106±3.4), (113±5.5) and (112±3,4) ng/dL, respectively, and were not statistically significant. The means of FT4 in CAPD, HD and normal subjects were (19.2±1.3), (15.8±1) and (14.3±0.6) pmol/l, respectively (p<0.02). The mean for FT4 in CAPD was higher than that of HD and normal subjects (p<0.001). The means of FT3 in CAPD, HD and normal subjects were (2.9±0.1), (3.1±0.1) and (3.8±0.1) pmol/L respectively (p<0.0001). In CAPD patients, FT3 was lower than in normal subjects (p<0.01), but no statistically significant difference with HD was seen. The TBG levels in the dialysate was 3.6±0.3 IU/ml, and its serum level in CAPD group was significantly higher than in others (16.7±0.8, 7.5±0.5 and 8.5±0.4IU/mL respectively p<0.001). TSH (Median,IQ25-75) in CAPD, HD and normal subjects were 1.4 (0.95–2.45), 1.2 (0.9–1.7) and 0.8 (0.6-1.1) mIU/ml respectively. TSH levels were higher in the CAPD group as compared with controls (p<0.001). Two cases of high TSH were observed in the CAPD group. The means of serum albumin in CAPD, HD and normal subjects were (3.6± 0.2) (3.8± 0.1) and (4.2±0.03) gr/dL respectively (p<0.0001), and these levels, in CAPD and HD patients, were lower than in normal subjects (p<0.0001). Apart from FT4 and TBG, all other thyroid function tests did not differ statistically between CAPD and HD individuars / patients. Considering the similarity in changes in TFTs in the CAPD and HD groups, it would seem that CAPD in comparison to HD would shows no additional changes in TFT.