The Role of pain related anxiety in the functioning of patients with knee osteoarthritis in Malaysia.

The aim of this cross-sectional study was to investigate the
relationship between pain related anxiety and the clinical
outcomes of function and pain in a group of Malaysian
patients with knee osteoarthritis (OA). A convenience sample
of 61 patients with knee OA were recruited from Seberang
Jaya hospital in Malaysia (18 male, 43 female; age 56±8years;
range, 45-84years). Three participants were excluded from
the analysis due to missing data.
Function was measured using the Knee Injury and
Osteoarthritis Outcome Score (KOOS), pain was measured
using the (0-10) pain numerical rating scale, and pain related
anxiety was measured using the Pain Anxiety Symptoms Scale
(PASS). Age, gender, BMI and duration of pain were also
recorded. Data was analysed using simple correlations and
multiple regression. Pain related anxiety was a statistically
significant independent predictor of function explaining 15%
of the variance within a regression model with pain (15%) and
age (5%) also making significant independent contributions to
the model. In contrast, pain related anxiety though correlated
with pain (r = 0.30, p=0.02) was not a statistically significant
independent predictor of pain. Pain related anxiety is a
significant independent predictor of function, but not pain,
in Malaysian patients with OA knee. This is the first study to
demonstrate a relationship between pain related anxiety and
function in an OA knee pain sample in a non-westernised
culture. The findings demonstrate the importance of pain
related anxiety as a construct across cultures. Pain related
anxiety should be addressed in the clinical management of
Malaysian patients with OA knee.