Temporal trends in health-related quality of life among hemodialysis patients in the United States

Abstract

Background and objectives: Health-related quality of life (HRQOL) is a measure of the well being of hemodialysis patients and an independent prognostic predictor. Our aim was to determine whether HRQOL among hemodialysis patients has changed over time.

Design, setting, participants, & measurements: We retrospectively analyzed data collected by Dialysis Clinic, Inc. from adult patients starting hemodialysis between January 1, 1997 and May 31, 2006. The primary outcome was HRQOL assessed by Short Form 36, 6 to 18 months after and closest to the 1-year anniversary of starting hemodialysis. Secular trends were analyzed by linear regression for continuous variables and logistic regression for categorical ones. Year of starting dialysis was the predictor. A five-point difference on a 0 to 100 scale was considered clinically significant.

Results: Short Form 36 scores were available for 11,079 patients. Role physical, general health, vitality, social functioning, and physical component summary scores were unchanged among patients over the study period. Statistically significant (P < 0.05) but clinically insignificant changes were observed in physical functioning (-0.2 points/yr), bodily pain (+0.2 points/yr), mental health (+0.15 points/yr), and mental component summary scores (+0.13 points/yr). Only role emotional showed clinically significant improvement. Trends were unchanged after adjusting for age, gender, race, diabetes, hemoglobin, phosphorous, Kt/V, and albumin.

Conclusions: Most HRQOL domains showed either no statistically significant change or statistically but not clinically significant change over almost a decade. These results suggest that, despite important developments in hemodialysis care since 1997, little progress was made in improving HRQOL of hemodialysis patients.

Figure 1.

Secular trends (1/1997 to 5/2006) in mean (±SEM) laboratory values of patients with SF-36 data between 6 and 18 months after starting hemodialysis (n = 11,079): Kt/V (1,004 missing values) (A), serum albumin concentration (1,373 missing values) (B), phosphorous concentration (1,270 missing values) (C), and hemoglobin concentration (1,214 missing values) (D). The values chosen were those closest in time to the date of SF-36 questionnaire administration.

Figure 2.

Secular trends (1/1997 to 5/2006), in mean HRQOL component summary scores, assessed by the SF-36 scores between 6 and 18 months after and closest to the 1-year anniversary of starting hemodialysis (n = 11,079): Physical Component summary score (A) and Mental Component summary score (B). Mean scores (●) and regression line are shown.