Optimizing dialysis dose in the context of frailty: an exploratory study

Frailty is a multicausal syndrome characterized by a decrease in strength, resistance and physiological function, which makes the individual vulnerable and dependent, and increases his/her mortality. This syndrome is more prevalent among older individuals, and chronic kidney disease patients, particularly those on dialysis. Dialysis dose is currently standardized for hemodialysis (HD) patients regardless of their age and functional status. However, it has been postulated that the dialysis dose required in older patients, especially frail ones, should be lower, since it could increase their degree of frailty. Then, the purpose of this study was to evaluate if there would be a correlation between the dose of Kt/V and the degree of frailty in a population of adult patients on HD.

A cross-sectional study with 82 patients on HD in Barranquilla (Colombia) and Lobos (Argentina) was conducted. Socio-demographic and laboratory data, as well as dialysis doses (Kt/V) were recorded and scales of fragility, physical activity, gait and grip strength were applied. Then these data were correlated by a Spearman's correlation and a logistic regression.

CFS, social isolation, physical activity, gait speed, and prehensile strength tests were outside the reference ranges in the studied group. No significant correlation was found between dialysis dose and all the above mentioned functional tests. However, a significant and inverse correlation between physical activity and CFS was documented (score - 1.41 (CI - 2.1 to - 0.7).

No significant correlation was documented between Kt/V value and different parameters of the frailty status, but this status correlated significantly and inversely with physical activity in this group. Frailty status in hemodialysis patients was significantly higher in older individuals, although young individuals were not exempt from it.