Fries et al developed a score for predicting the risk of an adverse gastrointestinal event in a patient with Rheumatoid Arthritis taking NSAIDS (non-steroidal anti-inflammatory agents). This is based on risk factors identified using stepwise logistic regression. The authors are from the Stanford University School of Medicine.
NSAIDS included (available in 1991): aspirin, naproxen, ibuprofen, piroxicam, indomethacin, sulindac, meclofenamate, tolmetin, fenoprofen, ketoprofen, nonacetylated salicylates, salsalate, diflunisal, diclofenac.
Parameters associated with GI complications from NSAID use:
(1) age
(2) history of a previous NSAID GI side effect
(3) disability index or American Rheumatism Association (ARA) class
(4) NSAID dose as a fraction of maximum recommended dose
(5) current prednisone use (even low daily doses)
|
Parameter |
Finding |
Points |
|
history of previous NSAID GI side effect |
absent |
0 |
|
|
present |
1 |
|
disability index or ARA class |
disability 0, or ARA 1 |
0 |
|
|
disability 1, or ARA 2 |
1 |
|
|
disability 2, or ARA 3 |
2 |
|
|
disability 3, or ARA 4 |
3 |
|
current prednisone use |
absent |
0 |
|
|
present |
1 |
|
RA Function |
ARA class |
|
normal |
1 |
|
adequate |
2 |
|
limited |
3 |
|
unable |
4 |
GI event score =
= (2 * (age in years)) + (50 * (points for history of previous GI side effect)) + (10 * (points for disability index or ARA class)) + (15 * (NSAID dose as a fraction of maximum recommended daily dose)) + (40 * (points for current prednisone use))
risk per year of a GI event in a rheumatoid arthritis patient while on NSAIDs =
= ((GI event score) – 100) / 40
Performance:
• The actual risk vs predicted risk from the equation is shown in Figure 3, page 220. This shows a linear relation with a strong correlation.
Limitations:
• The predicted risk may be too high in a person taking a newer NSAID formulated for reduced GI toxicity.
Specialty: Gastroenterology, Pharmacology, clinical
ICD-10: ,
