Fall Injury Risk in Older Adults Increases after Dialysis Therapy Initiation

Among community-dwelling older adults, falls are the leading cause of injury-related hospitalizations and may lead to disability and death. More than one in three older adults fall each year, and nearly half of those falls result in injury. Earlier studies have demonstrated that serious fall injuries commonly occur among older adults with chronic kidney disease (CKD); higher levels of albuminuria may confer higher risk.

Studies focusing on older adults receiving treatment with long-term dialysis demonstrated that nearly half of those patients may fall each year. Falls among older adults on dialysis therapy are associated with greater risk of serious injury and death compared with those who do not fall. However, those earlier studies of falls in this patient population have focused on prevalent dialysis patients recruited from single dialysis centers. It is possible that the increase in rates of serious fall injuries is due to initiation of dialysis therapy occurring in the setting of acute illness, indicating worsening health and functional decline.

According to Laura C. Plantinga, PhD, and colleagues, an awareness of rates of serious fall injuries before and after initiation of dialysis therapy may be an aid in identification of periods of high risk that could benefit from multicomponent strategies to reduce falls. The researchers conducted a retrospective cohort study of claims data from the 2 years spanning dialysis therapy initiation among patients initiating dialysis therapy from 2010 to 2012.

The study was designed to determine the rate of serious fall injuries among older adults receiving hemodialysis and whether the rate differs before and after dialysis initiation. The researchers also examined whether the association of timing with serious fall injury differs according to patient characteristics. The researchers reported study results in the American Journal of Kidney Diseases [2017;70(1):76-83].

Definitions for serious falls were derived from diagnostic codes for falls in combination with fractures, brain injuries, or joint dislocation. Estimates of incidence rate ratios, both overall and stratified, for post- versus pre-dialysis therapy initiation periods were made using generalized estimating equation models with a negative binomial link.

The researchers analyzed data on claims from 81,653 Medicare beneficiaries 67 to 100 years of age with end-stage renal disease (ESRD). Mean age was 77 years, 47% were women, and 66% were non-Hispanic white. Fifty-five percent had diabetes and 88% had comorbid hypertension. Approximately 10% were unable to walk at initiation of dialysis therapy, 18% required assistance with activities of daily living, and 14% were institutionalized.

Compared with those without a fall injury prior to initiation of dialysis therapy, beneficiaries who had at least one fall injury prior to initiation of dialysis therapy were older, more likely to be women, more likely to be white, more likely to have dialysis therapy initiated during an inpatient hospitalization, and more likely to be unable to walk or transfer, need assistance with activities of daily living, and be institutionalized. Likewise, compared with those without serious fall injuries following initiation of dialysis therapy, beneficiaries with at least one serious fall injury post-dialysis therapy initiation were older, more likely to be women, and more likely to be white.

There were no differences in pre-ESRD care from a nephrologist, inpatient dialysis therapy initiation, albumin levels, and the ability to walk between those with at least one serious fall injury following initiation of dialysis therapy and those without a serious fall injury. The differences in ability to transfer, needing assistance with activities of daily living, and being institutionalized stratified by the occurrence of serious fall injuries were of lesser magnitude in the post-dialysis therapy initiation period.

The researchers conducted an interrupted time series analysis of falls per month in this cohort; the average baseline percentage of patients having a serious fall injury per month was 0.27% in the pre-dialysis initiation period, with an absolute increase of 0.21% between predicted values at initiation of dialysis therapy from the pre- and post-dialysis therapy initiation models. When the analyses were conducted among both hemodialysis and peritoneal dialysis patients, results were similar.

Limitations cited by the authors included limited data for potential mechanisms of serious fall injuries, and lack of information on location and timing of falls, limiting the development of strategies to prevent falls in this patient population. Further, use of claims data may have led to misclassification, and due to the observational nature of the study, there was the potential for residual confounding by unmeasured factors such as history of noninjurious falls, measures of physical performance (gait speed, balance, and lower-extremity strength), and the use of assistive devices (walkers and canes).

“In conclusion, serious fall injuries are common among older Medicare beneficiaries receiving hemodialysis. The rate of serious falls was higher in the post- versus the pre-dialysis therapy initiation period for all patients. Patients at lowest risk for falls by other factors, such as those who were younger, able to walk and transfer, and not institutionalized and had better nutritional status had the highest differential risk across the two periods. Risk for falls following dialysis therapy initiation should be discussed with patients initiating dialysis therapy, and strategies to reduce fall and associated injury risk should be considered in this high-risk population,” the researchers said.

Takeaway Points

  1. Serious injury due to a fall is common among community-dwelling older adults; researchers conducted a retrospective cohort study to examine the rates of falls among Medicare beneficiaries initiating hemodialysis therapy.
  2. In the pre-dialysis therapy initiation period, the annual rate of serious falls was 64.4 per 1000 patient-years. In the period following initiation of dialysis therapy, the rate was 107.8 per 1000 patient-years.
  3. Patients who were younger, had nephrology care prior to development of end-stage renal disease, had albumin levels >3 g/dL, were able to walk and transfer, did not need assistance with activities of daily living, and were not institutionalized had greater magnitude in the relative rates of serious fall injuries in the pre- and post-dialysis initiation periods compared with relative rates among their counterparts.