Pentoxifylline, progression of chronic kidney disease (CKD) and cardiovascular mortality: long-term follow-up of a randomized clinical trial.

BACKGROUND: Pentoxifylline could reduce proteinuria and slow renal disease progression. We previously conducted a single-blind, randomized, controlled trial that showed that pentoxifylline decreases inflammatory markers and stabilizes renal function. SETTING AND PARTICIPANTS: 91 participants (46 in the pentoxifylline group and 45 in the control group) followed up for 7 additional years. STUDY DESIGN: Post hoc analysis of a long-term follow-up after completion of the 12-months trial. INTERVENTION: Pentoxifylline treatment (400 mg/twice a day) or standard treatment. OUTCOME: Renal event (defined as starting dialysis therapy and/or doubling serum creatinine and/or ≥ 50% decrease in estimated glomerular filtration rate) and cardiovascular mortality. RESULTS: During follow-up, a renal event was recorded in 24 patients from control group (13 initiated dialysis therapy and serum creatinine doubled in 11) and 11 patients from PTF group (7 initiated dialysis and serum creatinine doubled in 4) (log Rank: 5.822, p = 0.016). The possible protector effect of PTF was more significant in albuminuric patients and was independently of diabetes mellitus presence. Treatment with PTF reduced the renal events by 35% compared to the control group in a Cox model adjusted for diabetes mellitus, albuminuria and basal renal function (HR 0.65 (0.45-0.94), p = 0.022). Cardiovascular mortality was significantly reduced in PTF treatment (2 patients vs. 10 in control group) (log Rank 5.0977, p = 0.024). PTF treatment reduced cardiovascular mortality in 55% adjusted for diabetes mellitus and age (HR 0.45 (0.21-0.98), p = 0.044) (Table 3). LIMITATIONS: Small sample size, single center, not double blind and post hoc follow-up analysis. CONCLUSIONS: Long-term treatment with pentoxifylline may slow the rate of progression of kidney disease and reduce cardiovascular risk.

Intraperitoneal fluid overestimates hydration status assessment by bioimpedance spectroscopy.

BACKGROUND: Bioimpedance spectroscopy (BIS) is a valuable tool to assess nutrition and volume status in peritoneal dialysis (PD) patients. However, data about the influence of intraperitoneal fluid on body composition measures are conflicting, and there is no clear consensus about whether the abdomen should be drained before the procedure. We designed a comparison study to detect the influence of intra-abdominal fluid on BIS results. METHODS: We performed 73 pairs of BIS measurements in 34 stable PD patients, first with the peritoneum filled with a 1.36% glucose dialysate solution and then after the solution was drained. Patients stayed in the supine position for 10 minutes before the BIS procedure, and the electrodes were not moved between measures. Clinical and demographic data were collected, as were analytic parameters of nutrition and volume status. RESULTS: Fluid overload is overestimated when BIS is performed with a full abdomen (1.82 ± 1.73 L vs 1.64 ± 1.68 L, p = 0.043). We also found a spurious overestimation in extracellular water (16.40 ± 3.21 L vs 16.24 ± 3.16 L, p < 0.001) and in relative overhydration (8.29% ± 6.96% vs 7.14% ± 6.79%, p = 0.017). No differences in intracellular water or parameters of nutrition were found. We observed negative correlations for the extracellular water overestimation with age (r = -0.245, p = 0.037), serum B-type natriuretic peptide (r = -0.366, p = 0.036), body mass index (r = -0.248, p = 0.035), and lean tissue index (r = -0.427, p = 0.001). The difference in extracellular water correlated only with body mass index (r = -0.259, p = 0.039). We also found that, assessed at 50 KHz, whole-body impedance (-4.52 ± 8.37, p = 0.001) and phase angle (-0.08 ± 0.23 degrees, p = 0.002) were both lower when BIS was performed in patients with a full abdomen. CONCLUSIONS: Fluid overload is overestimated by BIS when performed in patients with dialysate in the peritoneum. The observed differences are greater in younger, more poorly nourished, or less overhydrated patients. If more precise results are required, we suggest that the abdomen be drained before BIS is performed.