Recovery Time Related to Quality of Life and Mortality in Hemodialysis Patients

Patients with poor health-related quality of life (HRQoL) and high risk of hospitalization and mortality can be identified using patient-reported recovery time. That was the primary finding of a prospective cohort study conducted by Hugh C. Rayner, MD, FRCP, and colleagues. The researchers reported results in the American Journal of Kidney Diseases [2014.64(1):86-94].

HRQoL is impacted to a great degree by end-stage renal disease and dialysis, which in turn can predict hospitalization and mortality. There are few data on how recovery following a dialysis session affects HRQol or how hemodialysis can be modified to shorten recovery time.

A previous study validated the question “How long does it take you to recover form a dialysis session?” in 46 patients in Canada. In that study, reported recovery time was correlated with the physical component of HRQol, was stable over 3 months, and had high test-retest correlation. There was patient-reported shortening of recovery time in patients changing to daily or nocturnal dialysis.

The researchers in the current study examined the recovery time question in a large representative sample of patients in 12 countries receiving hemodialysis 3 times per week. The primary areas of interest were: (1) the correlation of reported recovery time with other measures of health status, and (2) whether reported recovery time predicts hospitalization and mortality. The associations of reported recovery time with patient characteristics and treatment variables were also examined.

The researchers utilized data on 6040 patients in DOPPS (Dialysis Outcomes and Practice Patterns Study). The responses to the question on recovery time were categorized as <2, 2 to 6, 7 to 12, or >12 hours. Of the 6040 patients, 32% (n=1940) reported recovery time of <2 hours, 41% (n=2485) 2 to 6 hours, 17% (n=1015) 7 to 12 hours, and 10% (n=600) reported recovery time of >12 hours. The highest percentage of patients reporting recovery time >6 hours was in Italy (39%); the lowest was in Japan (18%).

Proportional odds (ordinal) logistic regression demonstrated that male sex (adjusted odds ratio [OR], 0.86; 95% confidence interval [CI], 0.77-0.97), full-time employment (adjusted OR, 0.73; 95% CI, 0.59-0.91), and higher serum albumin level (adjusted OR, 0.89 per 0.5 g/dL; 95% CI, 0.83-0.95) were associated with shorter recovery time.

Factors associated with longer recovery time were older age (adjusted OR, 1.03 per 5 years; 95% CI, 1.01-1.06), dialysis vintage (adjusted OR, 1.02 per year; 95% CI, 1.01-1.03), body mass index [BMI] (adjusted OR, 1.07 per 5-unit higher BMI; 95% CI, 1.02-1.12), diabetes (adjusted OR, 1.14; 95% CI, 1.02-1.27), and psychiatric disorders (adjusted OR, 1.39; 95% CI, 1.20-1.62).

“Note that proportional ORs can be interpreted at any cutoff point of ordered recovery time categories; that is <2 versus ≥2 hours, ≤6 hours versus ≥7 hours, or ≤12 versus ≥12 hours,” the researchers said.

Dialysis-related treatment variables were also associated with patients reporting longer time. Variables included greater intradialytic weight loss (adjusted OR, 1.04 per 1% greater; 95% CI, 1.00-110) and longer dialysis session duration (adjusted OR, 1.05 per 30 minutes longer; 95% CI, 1.00-1.10).

Compared with an ultrafiltration rate of 5 to 15 mL/min, both slow and fast ultrafiltration rates (<5 and >15 mL/min, respectively) were associated with shorter patient-reported recovery time (adjusted OR 0.86 [95% CI, 0.75-0.99] and 0.73 [95% CI, 0.61-0.87], respectively, in models excluding session length and intradialytic weight loss.

Longer recovery time was associated with prescription of dialysate sodium concentration <140 versus 140 mEq/L (adjusted OR, 1.34; 95% CI, 1.11-1.16). This association was not significantly affected with additional adjustment for serum sodium level (adjusted OR, 1.33; 95% CI, 1.11-1.59). There was a consistent association specifically for dialysate sodium concentration of 138 versus 140 mEq/L (adjusted OR, 1.37; 95% CI, 1.11-1.70).

In nonindividualized facilities (where a single dialysate sodium concentration was used for ≥90% of patients), the association of longer reported recovery time with dialysate sodium concentration <140 versus 140 mEq/L was stronger (adjusted OR, 1.72; 95% CI, 1.37-2.16; P for interaction between dialysate sodium concentration and type of facility [individualized vs nonindividualized]=.01; n=3181).

Among patients reporting longer recovery times, reported symptoms related to kidney failure, including pruritus, trouble falling asleep, and feeling depressed. Those patients also reported fewer activities of daily living. There was an inverse correlation of reported recovery time and Kidney Disease Quality of Life survey measures.

During a median follow-up of 16 months, hospitalization events were recorded for 52% of patients (n=3119) and 14% (n=826) died. Following adjustment for demographic and comorbid factors, there was a positive and monotonic association of patient-reported recovery time and rates of first hospitalization (adjusted hazard ratio [HR] per additional hour of recovery time, 1.03; 955 CI, 1.02-1.04) and all-cause mortality (adjusted HR, 1.05; 95% CI, 1.03-1.07). There was as slight attenuation in the associations following further adjustment for patient-reported symptoms (adjusted HRs for first hospitalization and mortality, 1.02 and 1.903, respectively, both P<.01).

Limitations to the study cited by the authors included the observational design allowing the possibility of unmeasured confounding or other sources creating bias in the observed associations, and not capturing the time of day of the dialysis to study the possibility that patients who slept soon after finishing dialysis may have included time spent asleep in their reported recovery time.

In conclusion, the researchers said, “There is wide variation in the time it takes for patients to recover after a dialysis session. The question “How long does it take you to recover from a dialysis session?” is a simple and meaningful self-reported measure that can be included in the clinical assessment of hemodialysis patients and possibly used as an audit measure of the quality of dialysis treatment. It helps identify patients with poorer HRQoL and higher risk of hospitalization and mortality. Interventions to reduce recovery time and possibly improve clinical outcomes, such as increasing dialysate sodium concentration, need to be tested in randomized studies.”

Takeaway Points

  1. The researchers in the current study examined the recovery time question in a large representative sample of patients in 12 countries receiving hemodialysis 3 times per week.
  2. Factors associated with longer recovery time were older age, dialysis vintage body mass index, diabetes, and psychiatric disorders.
  3. There was a positive and monotonic association of patient-reported recovery time and rates of first hospitalization and all-cause mortality.