Fluid overload in palliative cancer patients, a prospective observational cohort study

Fluid overload is a common and distressing complication in palliative cancer patients, often accompanied by shortness of breath and malnutrition. Understanding the prognostic implications of fluid accumulation in this population is crucial for improving patient care and identifying potential therapeutic avenues.

The aim of this study was to better understand the frequency of fluid accumulation in end-stage cancer patients and its impact on survival.

We prospectively recruited 276 cancer patients in palliative care (age 65±12 years, 47.5% female, life expectancy ≤12 months at baseline). Presence of pleural effusion, ascites, and peripheral edema was evaluated through clinical examination and sonography. Performance function was assessed using the Palliative Performance Scale.

Pleural effusion was present in 153 (55%), ascites in 88 (32%) and peripheral edema in 82 (30%) patients. Multivariable survival analysis (adjusted for age, sex, cancer type and stage, Eastern Cooperative Oncology Group performance status, chronic kidney disease, heart failure, antibiotic treated infection, and protein deficiency) showed that presence of pleural effusion, ascites, and peripheral edema predicted mortality (HR 1.35, 95% CI 1.04-1.75, p=0.024; HR 1.91, 95% CI 1.45-2.53, p<0.001; HR 1.53, 95% CI 1.16-2.02, p=0.003, respectively). Combination of all three questions led to a ‘fluid score’ of 0-3 points. This score predicted mortality well (multivariable adjusted HR per 1 point: HR 1.35, 95% CI 1.18-1.53, p<0.001). Patients were then grouped into three groups: 0 points, 1-2 points, or 3 points. Multivariable adjusted HR ‘3 vs. 0 points’: HR 2.20, 95% CI 1.42-3.41 p<0.001 and ‘1-2 vs. 0 points’: HR 1.52, 95% CI 1.13-2.03, p=0.005. The fluid score correlated with CRP (r=0.25, p<0.001) and dyspnea measured through NYHA classes or Borg Scale (r=0.27, p<0.001; r=0.24, p<0.001, respectively). The fluid score showed a negative correlation with serum albumin levels (r=-0.36, p<0.001), the Palliative Performance Scale (r=-0.21, p=0.006), the ability to use the toilet (r=-0.24, p=0.007) and maximum handgrip strength (r=-0.25, p<0.001).

Pleural effusion, ascites and peripheral edema in palliative cancer patients are associated with reduced life expectancy, dyspnea and hypoalbuminemia. Each of these three questions contributes to higher overall mortality, emphasizing the importance of early identification and management of fluid overload in this patient population.