Patients who electively withdraw from dialysis experience an increased rate of medical events and institutionalization in the months leading up to discontinuation, new study findings suggest.
Factors that increase the likelihood of withdrawal include older age, white race, and female sex.
“We found that in the month or so prior to elective dialysis withdrawal, rates of major medical events, hospitalizations, and use of skilled nursing facilities dramatically increased,” lead investigator James B. Wetmore, MD, MS, of the Chronic Disease Research Group at the Hennepin County Medical Center in Minneapolis, Minnesota, told Renal & Urology News. “While that itself was not unexpected, we saw that our durable medical equipment-based score that seems to capture functional status increased—worsened—dramatically in the lead-up to withdrawal. This suggested to us that worsening functional status might herald impending dialysis withdrawal.”
Using the US Renal Data System database, Dr Wetmore and his colleagues compared 18,367 patients who withdrew from dialysis and 220,443 who did not. “We hypothesized that the period immediately prior to elective dialysis withdrawal would be associated with an increase in major medical events and time spent in the hospital or a skilled nursing facility,” Dr Wetmore said.
A unique feature of their study was the creation of a presumptive functional status score, termed a “morbidity score” in the paper, based on Medicare claims for durable medical equipment such as hospital beds in the home, bedside commodes, wheelchairs, walkers, and the like. “We thought that heavy use of this type of equipment likely indicated poor functional status and, perhaps more profoundly, frailty.”
Rates of medical events and institutionalization increased from 9 months to 1 month before withdrawal, Dr Wetmore’s group reported online ahead of print in the American Journal of Kidney Diseases. For example, among patients who withdrew, the rate of any medical event roughly quadrupled between 9 months before withdrawal and 1 month before withdrawal. The rate of any hospitalization during the same period increased roughly 6-fold. By comparison, among patients who did not withdraw, the rates of any medical event or of hospitalization increased by less than 20%.
The odds of withdrawal increased with increasing morbidity score. An increasing score signified worse morbidity and, as Dr. Wetmore explained, presumably worse functional status. Compared with a score of 0, a score of 1–2, 3–4, 5–6, and 7-fold or more was associated with a significant 2.8-, 3.5-, 5.1-, and 12.1-fold increased odds of dialysis withdrawal, respectively.
Patients who withdrew from dialysis had a mean age of 75.3 years, whereas those who did not withdraw had a mean age of 66.2 years. Compared with patients aged 65 to 74 years, those aged 85 years and older had a significant 61% higher adjusted odds of withdrawal, whereas those aged 18 to 44 years had a significant 64% lower adjusted odds of withdrawal.
Compared with whites, blacks, Asians, and Hispanics had a significant 64%, 53%, and 54% lower adjusted odds of withdrawal, respectively. “Elective dialysis withdrawal is an increasingly important phenomenon to study given society’s justifiably increased interest in end-of-life care, such as palliative care that emphasizes quality of life and relief of suffering,” Dr Wetmore said. “There appear to differences in the withdrawal experience between races, which we posit is likely due to cultural or other as-yet-defined factors.”
The investigators also found that the odds of withdrawal were a significant 7% higher among women compared with men.
Further, the study found that elective withdrawal in the hospital versus outside the hospital was more likely among women than men and more likely among blacks and Hispanics compared with whites. Patients aged 75 years and older were more likely than younger patients with withdraw outside the hospital than in the hospital.
Longer dialysis duration was associated with an increased likelihood of withdrawal. Compared with patients with a dialysis duration of 3 to less than 4 years, those with a duration of 1 to less than 2 years had a significant 45% lower odds of withdrawal, whereas patients with a dialysis duration of 5 years or more had a significant 37% increased odds of withdrawal.
Wetmore JB, Hu HYY, Gilbertson DT, Liu J. Factors associated with withdrawal from maintenance dialysis: A case-control analysis. Am J Kidney Dis. 2018 Jan 10. doi: 10.1053/j.ajkd.2017.10.025