Morbidity, mortality and quality of life in the ageing haemodialysis population: results from the ELDERLY study

Abstract

Background: The physical-functional and social-emotional health as well as survival of the elderly (≥75 years of age) haemodialysis patient is commonly thought to be poor. In a prospective, multicentre, non-interventional, observational study, the morbidity, mortality and quality of life (QoL) in this patient group were examined and compared with a younger cohort.

Methods: In 92 German dialysis centres, 2507 prevalent patients 19-98 years of age on haemodialysis for a median of 19.2 months were included in a drug monitoring study of darbepoetin alfa. To examine outcome and QoL parameters, 24 months of follow-up data in the age cohorts <75 and ≥75 years were analysed. Treatment parameters, adverse and intercurrent events, hospitalizations, morbidity and mortality were assessed. QoL was evaluated by means of the 47-item Functional Assessment of Chronic Illness Therapy-Anaemia score (FACT-An, version 4).

Results: The 2-year mortality rate was 34.7% for the older cohort and 15.8% for the younger cohort. The mortality rate for the haemodialysed elderly patients was 6.2% higher in absolute value compared with the age-matched background population. A powerful predictor of survival was the baseline FACT-An score and a close correlation with the 20-item anaemia subscale (AnS) was demonstrated. While the social QoL in the elderly patients was more stable than in the younger cohort (leading to equivalent values at the end of the study period), a pronounced deterioration of physical and functional status was observed. The median number of all-cause hospital days per patient-year was 12.3 for the elderly cohort and 8.9 for the younger patient population. The overall 24-month hospitalization rate was only marginally higher in the elderly cohort (34.0 versus 33.3%).

Conclusions: In this observational study, the mortality rate of elderly haemodialysis patients was not exceedingly high compared with the age-matched background population. Furthermore, the hospitalization rate was only slightly higher compared with the younger age group and the median yearly hospitalization time trended lower compared with registry data. The social well-being of elderly haemodialysis patients showed a less pronounced decline over time and was equal to the score of the younger cohort at the end of the study period. The physical and functional status in the elderly patients was lower and showed a sharper decline over time. The baseline FACT-An score correlated closely with the 24-month survival probability.

Keywords: chronic haemodialysis; elderly; quality of life; survival analysis; vascular access.

Fig. 1.

Age-specific yearly mortality rate of haemodialysis patients in the ELDERLY study compared with the German background population (DZA: Deutsches Zentrum fuer Altersfragen). Detailed numbers are demonstrated at the bottom of Table 3.

Fig. 2.

Kaplan–Meier estimates for survival stratified by the baseline FACT-An score. The survival probability at the end of the observation period was 0.89, 0.78 and 0.64, respectively.

Fig. 3.

Lattice plots of the QoL parameters (maximum likelihood estimates and regression line) at baseline, 12 and 24 months (filled circle: <75 years; filled triangle: ≥75 years).

Fig. 4.

Kaplan–Meier estimates for survival stratified for age and FACT-An score. The survival probability at the end of the observation period was 0.92, 0.81, 0.69 and 0.55, respectively.