Missed Hemodialysis Treatments Associated with Increased Risk of Mortality

Hemodialysis therapy is typically provided three times a week for several hours for each treatment, creating considerable burdens on patients. There are wide variations in the extent to which those burdens affect patients’ quality of life; there may be negative effects on patient adherence to their treatment regimens among those who find their regimens particularly burdensome.

One form of nonadherence is missing a prescribed hemodialysis treatment (not due to hospitalization). Previous studies have found associations between missed treatments and poor clinical outcomes. Using data from DOPPS (Dialysis Outcomes and Practice Patterns Study), an international prospective cohort study of hemodialysis care and outcomes, Issa Al Salmi, MD, and colleagues reported findings related to missed treatments among patients who were prescribed thrice-weekly hemodialysis. The data were from DOPPS phase 5, 2012-2015. Results were reported in the American Journal of Kidney Diseases [2018;72(5):634-643].

Eligible participants, from 20 countries, were on hemodialysis therapy for >120 days. The researchers performed longitudinal and cross-sectional analyses based on the 4493 patients from countries in which the 4-month missed treatment risk was >5%.

The main predictor of patient outcomes was one or more missed treatments in the 4 months prior to DOPPS phase 5 enrollment; predictors of missed treatments included country, patient characteristics, and clinical factors. The outcomes of interest were mortality, hospitalization, laboratory measures, patient-reported outcomes, and 4-month missed treatment risk.

Of the 9731 eligible patients, 8501 (87%) had data available on missed scheduled hemodialysis treatments during the 4-month baseline period. The proportion of patients missing at least one treatment in the 4-month baseline period varied from 20% to 24% in the six Gulf Cooperation Council (GCC) countries and the United States to <1% in Italy and Japan. Most of the patients missed one or more treatments during only 1 month in the 4-month period.

In some countries there was wide variation across facilities in the percentage of patients who missed one or more treatments over the 4-month period. There was no association between season of the year and occurrence of missed treatments, both overall and within the United States.

Analyses that described patient characteristics, predictors, and outcomes associated with missing at least one hemodialysis session in the 4-month baseline period were conducted in countries in which the 4-month risk for missed treatments exceeded 5% (n=4493 patients).

Patients who were younger, or had shorter dialysis vintage, shorter prescribed treatment time, lower achieved Kt/V, symptoms of depression (Center for Epidemiologic Studies Depression  [CES-D] score >10), or typically traveled >1 hour to hemodialysis sessions were more likely to have one or more missed treatments over 4 months. The relationship with travel time was more pronounced in the United States (adjusted odds ratio [aOR], 3.17; 95% confidence interval [CI], 1.41-7.16) compared with other countries (aOR, 1.60; 95% CI, 0.94-2.72). There were no strong associations between patient comorbid factors or having residual renal output >200 mL of urine per day and the odds of at least one missed treatment. In addition, there was little variation by sex, with the exception of the GCC, where the odds were nominally greater in men.

Patients with one or more missed treatments were more likely to have hyperphosphatemia, parathyroid hormone level >300 pg/mL, hemoglobin level <10 g/dL, and single-pool Kt/V <1.2. However, there was very little difference in the values of serum potassium, albumin, creatinine, and intradialytic weight loss between patients with and without one or more missed treatments over 4 months.

In an analysis of patient-reported outcomes, those with one or more missed treatments reported substantially greater burden of kidney disease, higher mean CES-D scores (indicative of greater depression symptoms), poorer perceived general health, and lower Kidney Disease Quality of Life Mental Component Summary scores. There was little difference in Physical Component Summary scores between those with versus those without one or more missed treatments.

There was a positive association between missed treatments and all-cause mortality (hazard ratio, 1.68; 95% CI, 1.37-2.05), cardiovascular mortality, sudden death/cardiac arrest, hospitalization, serum phosphorus level >5.5 mg/dL, and worse general and mental health.

Possible residual confounding and temporal ambiguity in the cross-sectional analyses were cited as limitations to the findings.

In conclusion, the researchers said, “In the countries with a 4-month missed treatment risk >5%, hemodialysis patients were more likely to die, be hospitalized, and have poorer patient-reported outcomes and laboratory measures when one or more missed treatments occurred in a 4-month period. The large variation in missed treatments across 20 nations suggests that their occurrence is potentially modifiable, especially in the United States and other countries in which missed treatment risk is high.”

Takeaway Points

  1. Researchers conducted an analysis of data from DOPPS phase 5 (2012-2015) to examine the phenomenon of missed treatments in hemodialysis patients and the relationship of missed treatments with patient characteristics, treatment measures, and clinical and patient-reported outcomes.
  2. There was wide variation across the 20 countries in the DOPPS trial, ranging from <1% in Italy and Japan to 24% in the United States.
  3. In countries where the 4-month missed treatment risk was >5%, hemodialysis patients who missed one or more treatments in a 4-month period were more likely to die, be hospitalized, and have poorer patient-reported outcomes and laboratory measures.