Outcomes from symptom and economic evaluation of fluid restriction in persons with heart failure

Introduction: Fluid restrictions (FR) are routinely prescribed for persons with heart failure (HF), yet little is known regarding patient adherence and outcomes from this self-care behavior. Purpose: To evaluate adherence and outcomes in persons with HF randomized to receive attention control (AC) or an education and behavioral intervention (EBI) consisting of FR education, rationale, skill building for quantifying fluid intake, strategies, and goal setting. Methods: 25 NYHA Class II-IV persons (age 44-83 years, 56% male, 20% minority, mean EF 23.0 +11.7%, on standard HF medications) were evaluated at baseline, 3 and 6 months. Measures included adherence with the prescribed FR, physical measures [BNP, congestion score, and intrathoracic impedance (IIM)], and patient reported outcomes (thirst distress, HF symptoms, and HRQL), analyzed using multi-level mixed models, RM-ANCOVA, and time series analyses. Results: Relationships between self-reported fluid status, fluid congestion, symptom distress, and HRQL were observed. While the sample size was small, moderate effect sizes were noted in all measures that trended toward significance (p<.10). Patients randomized to the EBI group demonstrated decreased total fluid consumption (paired t(11)= 2.243, p< .05, large effect size (ES) 0.56), less frequency of HF symptoms (t(24.720) = -2.048, p = .05, moderate ES 0.38), less severity of symptoms (t(24.335) = -1.914, p = .07, moderate ES 0.36), and less interference of HF symptoms with physical activity (t(25.647) = -2.032, p = .05, moderate ES 0.37). Thirst distress was noted to worsen in this group (t(27.424) = 1.993, p = .06, moderate ES 0.36) while HRQL did not change in the EBI group but improved in the AC (t(22.880) = -1.755, p = .09). Time series indicated a negative relationship between weight & IIM, positive correlation between weight & daily fluid intake, and a potential negative association between fluid intake & IIM. Conclusion: This pilot and feasibility study demonstrated that adherence with a prescribed FR is possible and may lead to improved typical HF symptoms, but may also increase symptoms of thirst. More research into the effects and benefits of FR including the level of FR that confers the best outcomes for the least patient distress, is warranted.