364
Conclusion
The Use of PROMs in PMR
PMR is a very heterogeneous disease with an important impact on patients’ lives.
There seems to be little evidence as to which set of criteria provides a reliable diag-
nosis or which outcomes are the most relevant to evaluate the most appropriate
treatment. In an effort to propose new outcome measures, PROs may play an impor-
tant role. The use of PROs is dramatically increasing in rheumatology. Most core
outcome sets or minimum domains to be measured in clinical trials include at least
one PRO [ 32 ].
PROs have been proven to show responsiveness [ 33 ] and distinguish routine
care from treat-to-target strategies as effectively as other measures in clinical trials
of RA patients [ 34 ]. In addition, the use of PROs may encourage the patient to have
an active role to help manage his or her own illness.
In PMR, an Outcome Measures in Rheumatology (OMERACT) special interest
group is working toward the development of a core set of outcomes, but pain, morn-
ing stiffness, fatigue, sleep disturbance, function, anxiety, and depression have been
initially identifi ed of interest [ 8 ]. In general, 3 PROs are commonly used across the
majority of rheumatic diseases and included in most core data sets: pain, physical
function, and the patient global assessment of disease activity [ 32 ]. In the system-
atic review previously presented, pain, morning stiffness, and physical function
were the PROs most frequently reported in PMR studies.
Pain is the most important symptom in patients with PMR and plays a crucial
role during the course of the disease. Pain is the principal feature of all diagnostic
criteria for PMR published so far [ 35 – 38 ] and it has been included as a central mea-
sure in multiple remission/fl are defi nition [ 9 ]. Pain is also the only mandatory crite-
ria in the EULAR response criteria for PMR [ 26 ].
Morning stiffness is also considered an important diagnostic clue in PMR, but it
is diffi cult to measure accurately, especially when using duration of morning stiff-
ness that has been reported to show poor test–retest reliability in PMR [ 7 ]. From the
patient’s perspective, morning stiffness is better described as what it prevents them
from doing, in relation to physical function, and it is less responsive to glucocorti-
coids in comparison to pain [ 24 ]. Morning stiffness has also been included in differ-
ent diagnostic criteria—lasting for more than 1 h [ 35 , 36 ]—as part of the response
criteria previously described [ 26 ], and in the PMR-AS [ 27 ].
Function through HAQ or MHAQ was only reported in 25 % of the articles from
the systematic review. This is a surprisingly low percentage, having taken into
account that both are generic instruments that can be used in any rheumatic diagno-
sis [ 39 ]. Function correlates with other measures of disease activity in PMR and is
responsive to change [ 40 , 41 ]. Moreover, function is a strong predictor of mortality
not only in patients with RA [ 42 ], but also in the general population [ 43 ].
I. Castrejon