A performance status is a global measure of a patient’s functional capacity
and has been shown to predict survival in patients near the end of life.
Several different performance status metrics have been developed to quantify
performance status, and among them, the Karnofsky performance status (KPS)
is the most often used. The KPS ranges from values of 100, signifying normal
functional status with no complaints nor evidence of disease, to zero, signifying
death. The complete spectrum of values for the KPS scale is reproduced below.
Karnofsky Performance Scale
%
Description -- Level of Functional Capacity
100
Normal, no complaints, no evidence of disease
90
Able to carry on normal activity, minor signs or symptoms of disease
80
Normal activity with effort, some signs or symptoms of disease
70
Cares for self, unable to carry on normal activity or to do active work
60
Requires occasional assistance, but is able to care for most needs
50
Requires considerale assistance and frequent medical care
40
Disabled, requires special care and assistance
30
Severely disabled, hospitalization is indicated although death is not
imminent
20
Hospitalization is necessary, very sick, active supportive treatment necessary
10
Moribund, fatal processes progressing rapidly
0
Dead
Source: Karnofsky, DA, Burchenal, JH. The
Clinical Evaluation of Chemotherapeutic Agents in Cancer. Pg.
196. IN: MacLeod CM (Ed), Evaluation of Chemotherapeutic Agents.
Columbia Univ Press, 1949.
Multiple studies have
reported associations between patients’ performance status and their
subsequent survival with lower performance status predicting shorter survivals.
The size of the association is described differently in different studies depending
on the statistical methods used, but several studies report that among patients
enrolled in palliative care programs, a KPS of less than 50% suggests a life
expectancy of fewer than 8 weeks (Evans
1985, Maltoni 1994,1995, Reuben 1988, Morita 1999, Llobera 2000).
The association between KPS value and survival in patients enrolled in palliative
care programs is described in the table below.
Predictors of Survival with Advanced Cancer under Palliative
Care
