Kidney Week

Abstract: FR-PO538

Predictors of Mobility Impairment over Time in Incident Dialysis Patients

Session Information

• Physical Activity, Body Composition, Metabolism: Clinical
  October 26, 2018 | Location: Exhibit Hall, San Diego Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Health Maintenance, Nutrition, and Metabolism

• 1302 Health Maintenance, Nutrition, and Metabolism: Clinical

Authors

• Moorthi, Ranjani N., Indiana University School of Medicine, Indianapolis, Indiana, United States

Ranjani N. Moorthi,

• Fadel, William F., Indiana University, Indianapolis, Indiana, United States

William F. Fadel,

• Cranor, Alissa Ann, Indiana University School of Medicine, Indianapolis, Indiana, United States

Alissa Ann Cranor,

• Hindi, Judy, Indiana University, Indianapolis, Indiana, United States

Judy Hindi,

• Lane, Kathleen A., Indiana University School of Medicine, Indianapolis, Indiana, United States

Kathleen A. Lane,

• Thadhani, Ravi I., Cedars-Sinai, Los Angeles, California, United States

Ravi I. Thadhani,

• Avin, Keith, Indiana University-Indianapolis, Indianapolis, Indiana, United States

Keith Avin,

• Moe, Sharon M., Indiana University School of Medicine, Indianapolis, Indiana, United States

Sharon M. Moe,

Background

Sarcopenia involves loss of muscle strength and/or mass that leads to loss in physical function (mobility impairment). Mobility impairment can be quantified by gait speed measures. In CKD, mobility loss is associated with hospitalizations, functional dependence and mortality. The trajectory of mobility over time in new dialysis patients is not well-characterized. We hypothesized that there are decreases in mobility over time in incident dialysis patients, independent of changes in muscle strength.

Methods

Gait speed was assessed in 195 subjects who were incident to outpatient dialysis by the 4-meter walk test at baseline, 6, 12 and 24 months. Maximum handgrip strength of 3 trials in both upper limbs was recorded at similar time points. Appendicular lean mass/ ht2 was measured by DXA. Mixed effects models were used to analyze changes in gait speed and identify predictors of change among covariates which included demographics, walking aids, self-reported health status, ESRD cause, time-varying muscle strength, baseline lean mass and physical activity.

Results

The mean age of the cohort was 54.3+/-13 years, with 53.3% male, 72.4% black and with a median of 93.7+/-72 days since dialysis start.There was an average decrease in gait speed of 0.023 m/s/yr. Lower grip strength at baseline was associated with lower gait speed trajectory over time (Figure). Age, use of walking aids, lower grip strength, diabetic nephropathy as cause of ESRD, self-reported poor ambulation and lower health utility were significantly associated with poor mobility over time in the adjusted mixed effects model (all p<0.05). Baseline lean mass or step counts did not affect these relationships.

Conclusion

There is loss of mobility with time in patients relatively new to dialysis. Loss of muscle strength is an independent risk factor for mobility impairment over time. Identifying risk factors for mobility loss may be used to target interventions like physical therapy, gait training and exercise.

Gait Speed Trajectory by Baseline Grip Strength

Funding

• NIDDK Support