Zink et al developed the Rheumatoid Arthritis Observation of Biologic Therapy (RABBIT) Risk Scores to identify patients with rheumatoid arthritis who are at increased risk for serious infections.
Patient selection: rheumatoid arthritis
Risk scores:
(1) for number of serious infections per 100 patient years
(2) percentage of patients with at least 1 infection per year
Parameters:
(1) age in years
(2) function by either FFbH (Funktionsfragebogen Hannover) or HAQ ("alternatively")
(3) chronic lung disease
(4) chronic renal disease
(5) history of serious infection
(6) number of treatment failures
(7) mean glucocorticoid dose in mg/day
(8) treatment with TNF inhibitor
|
Parameter |
Finding |
Points |
|
age in years |
<= 60 years of age |
0 |
|
|
> 60 years of age |
0.479 |
|
function |
FFbH |
-0.01014 * FFbH |
|
|
HAQ |
0.362 * ((HAQ) - 3.16) |
|
chronic lung disease |
no |
0 |
|
|
yes |
0.522 |
|
chronic renal disease |
no |
0 |
|
|
yes |
0.441 |
|
history of serious infection |
no |
0 |
|
|
yes |
0.748 |
|
number of treatment failures |
<= 5 |
0 |
|
|
> 5 |
0.443 |
|
glucocorticoid dose |
< 7.5 mg/d |
0 |
|
|
7.5 to 14 |
0.756 |
|
|
> 14 |
1.554 |
|
TNF inhibitor therapy |
none |
0 |
|
|
more than 3 months age |
0 |
|
|
within past 3 months |
0.593 |
X =
= SUM(points for all 8 parameters) - 3.996
number of serious infections per 100 patient years =
= 100*EXP(X)
|
Parameter |
Finding |
Points |
|
age in years |
<= 60 years of age |
0 |
|
|
> 60 years of age |
0.470 |
|
function |
FFbH |
-0.00865 * FFbH |
|
|
HAQ |
0.309 * ((HAQ) - 3.16) |
|
chronic lung disease |
no |
0 |
|
|
yes |
0.484 |
|
chronic renal disease |
no |
0 |
|
|
yes |
0.415 |
|
history of serious infection |
no |
0 |
|
|
yes |
0.992 |
|
number of treatment failures |
<= 5 |
0 |
|
|
> 5 |
0.397 |
|
glucocorticoid dose |
< 7.5 mg/d |
0 |
|
|
7.5 to 14 |
0.782 |
|
|
> 14 |
1.355 |
|
TNF inhibitor therapy |
none |
0 |
|
|
more than 3 months age |
0 |
|
|
within past 3 months |
0.589 |
Y =
= SUM(points for all 8 parameters) - 4.191
percentage of patients with at least 1 infection per year
= 100*(1-EXP((-1)*EXP(Y)))
Specialty: Immunology/Rheumatology
ICD-10: ,
