The Effect of Psychological Intervention on Thirst and Interdialytic Weight Gain in Patients on Chronic Hemodialysis: A Randomized Controlled Trial.
OBJECTIVE
Patients on hemodialysis (HD) are unable to eliminate excess fluid and must adhere to a regimen of dietary fluid restriction to prevent volume overload. Thirst represents a major obstacle to the achievement of such a goal. The aim of our study was (1) to assess the association of thirst and xerostomia, measured by validated questionnaires, Dialysis Thirst Inventory and Xerostomia Inventory with interdialytic weight gain (IDWG) and (2) to evaluate in a randomized controlled trial (RCT), the effect of psychological intervention on IDWG and thirst.


STUDY DESIGN
Cross-sectional evaluation of association of thirst and IDWG and single-blind RCT of psychological intervention on IDWG management.


SETTING
Outpatient dialysis unit.


SUBJECTS
The cross-sectional evaluation included 117 patients on HD (age, 71 ± 13 years); among these, 54 were selected for the RCT.


INTERVENTION
The questionnaires were administered to all the participating patients; IDWG (4-week average), Kt/V, predialysis blood pressure, dialyzate sodium, hematocrit, serum electrolytes, parathyroid hormone, and patients' medications were recorded. Fifty-four patients were randomized on a 1:1 basis to usual treatment (including dietary advice) or psychological intervention, consisting of group sessions, held once a week for 5 weeks; IDWG and all the other parameters were rechecked after 6 weeks and 6 months.


MAIN OUTCOME MEASURE
IDWG change from baseline.


RESULTS
Dialysis Thirst Inventory score was correlated with IDWG (ρ = 0.575; P < .001), body mass index (ρ = 0.257; P = .005), and inversely with age (ρ = -0.344; P < .001). A small but significant decrease of IDWG compared to baseline was observed in the intervention group (baseline 1332 ± 338 g/day; at 6 weeks, 1183 ± 258 g/day; at 6 months, 1203 ± 284 g/day; P < .001). No IDWG changes with respect to baseline occurred in controls (baseline 1310 ± 333 g/day; at 6 weeks, 1336 ± 340 g/day; at 6 months, 1323 ± 328 g/day; P = .57). The secondary outcomes were not affected by the intervention.


CONCLUSIONS
The findings of our study show that a psychological support may help managing IDWG in HD patients.