RA Outcomes in Patients Not Meeting Severity Criteria for Biologic Prescription Frederick Wolfe

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RA Outcomes in Patients Not Meeting Severity
Criteria for Biologic Prescription  Frederick
Wolfe Kaleb Michaud National Data Bank for
Rheumatic Diseases, Wichita, KS
ABSTRACT OBJECTIVES. Biologic therapy is an
effective but expensive therapy. Based on
available resources, regulators and insurance
payers often restrict access to this treatment to
patients with very severe rheumatoid arthritis
(RA). We explored the extent to which patients
with less than very severe RA (DAS-28 lt5.1) had
adverse outcomes and compared these outcome rates
with those with very severe RA. METHODS. We
studied the outcomes of 5,809 RA patients
enrolling in a longitudinal outcome study between
1999 and 2000. Follow-up continued through 2005.
We characterized severity classes using the
Patient Activity Scale (PAS). Mild (0-1.9),
moderate (1.9-3.8), severe (S_RA) (3.8-5.6) and
very severe RA (VS_RA) (5.6-10). For comparison,
a very severe PAS score is equivalent to a DAS-28
5.1. We examined three outcome measures,
mortality, work disability and total joint
replacement (TJR). Utility scores were determined
using a standard linear transformation of a VAS
Quality of Life (QOL) scale. Comparisons between
severity classes were performed using Cox
proportional hazards regression. RESULTS. At
baseline, 10.6 of patients were in the VS_RA
category, and a linear relationship existed
between QOL and PAS score (Figure 1). New TJRs
occurred in 1,264 patients. Adjusting for the
presence of previous TJR, age, sex and RA
duration, compared with patients with mild RA,
those with S_RA had a hazard ratio (HR) of 1.4
and those with VS_RA an HR of 1.5 (Table 1). We
evaluated work disability in 1,855 patients aged
60 years or less who were not work disabled. Work
disability occurred subsequently in 190 patients.
Compared with patients with mild RA, those with
S_RA had an HR of 2.6 and those with VS_RA an HR
of 3.8. When these analyses were extended to
mortality, controlling also for comorbidity, 533
deaths were noted. The HR for S_RA was 1.5 and
for VS_RA was 2.2 compared with those with mild
RA. CONCLUSIONS. As expected, adverse outcomes
were frequent in patients with VS_RA, patients
who would have been selected by the DAS-28 5.1
and similar criterion. However, the risk of
adverse outcomes was also substantially increased
in patients who did not satisfy the severity
criterion. These data indicate that adverse
outcomes and decreased QOL have no simple
cut-point and that restrictions to the use of
biologics follow economic rather than meaningful
severity indications.  
We evaluated work disability in 1,855 patients
aged 60 years or less who were not work disabled.
Work disability occurred subsequently in 190
patients. Compared with patients with mild RA,
those with severe RA had an HR of 2.6 and those
with very severe RA an HR of 3.8. When these
analyses were extended to mortality, controlling
also for comorbidity, 533 deaths were noted. The
HR for severe RA was 1.5 and for very severe RA
was 2.2 compared with those with mild RA.

• We characterized severity classes using the
  Patient Activity Scale (PAS).
• Mild RA activity 0-1.9
• Moderate RA activity 1.9-3.8
• Severe RA activity 3.8-5.6
• Very severe RA 5.6-10
• A very severe PAS score is equivalent to a DAS-28
  5.1.

Table 1. The risk of adverse RA outcomes
according to PAS category

CONCLUSIONS As expected, adverse outcomes were
frequent in patients with very severe RA,
patients who would have been selected by the
DAS-28 5.1 and similar criterion. However, the
risk of adverse outcomes was also substantially
increased in patients who did not satisfy the
severity criterion. These data indicate that
adverse outcomes and decreased QOL have no simple
cut-point and that restrictions to the use of
biologics follow economic rather than meaningful
severity indications.  
As the recommendation for use of biologic is
often linked to having a DAS score of 5.1 or
greater (PAS very active RA), we compared RA
patients with moderate, severe and very severe RA
to see whether having less than very severe RA
was also a risk for adverse RA Outcomes. New
total joint replacements occurred in 1,264
patients. Adjusting for the presence of previous
TJR, age, sex and RA duration, compared with
patients with mild RA, those with severe RA had a
hazard ratio (HR) of 1.4 and those with very
severe RA an HR of 1.5 (Table 1).
The PAS scores is linearly related to QOL.
Although very severe PAS scores are the
equivalent of a DAS score 5.1, there is no
discontinuity at the severe/very severe
interface. Instead, the relation is smooth and
linear.
This project was supported by a grant from Amgen,
Inc.