Journal of Rehabilitation Medicine 51-3 | Page 37
J Rehabil Med 2019; 51: 183–192
ORIGINAL REPORT
PREDICTORS OF CHRONIC PAIN INTENSITY, SPREAD AND SENSITIVITY IN THE
GENERAL POPULATION: A TWO-YEAR FOLLOW-UP STUDY FROM THE SWEPAIN
COHORT
Britt LARSSON, PhD 1 , Elena DRAGIOTI, PhD 1 , Anna GRIMBY-EKMAN, PhD 2 , Björn GERDLE, PhD 1 and Jonas BJÖRK, PhD 3
From the 1 Pain and Rehabilitation Centre, and Department of Medical and Health Sciences, Linköping University, Linköping, 2 Health
Metrics, University of Gothenburg, Gothenburg and 3 Division of Occupational and Environmental Medicine, Lund University, Lund, Sweden
Objective: To determine whether the intensity,
spread and sensitivity of chronic pain can be pre
dicted using demographic features, socioeconomic
conditions and comorbidities.
Design: A longitudinal study design was employed.
Data was collected at baseline and at 2-year follow-
up.
Setting: General population in south-eastern Sweden.
Subjects: A representative stratified random sam
ple of 34,000 individuals, between 18 and 85 years
of age, selected from a sampling frame of 404,661
individuals based on the Swedish Total Population
Register.
Methods: Eligible individuals were sent postal sur
veys in 2013 and 2015. The 2 surveys included the
same questions about basic demographic data, co
morbidities, and chronic pain intensity, spread and
sensitivity.
Results: Several socio-demographic features and co
morbidities at baseline were significant predictors of
characteristics of pain (intensity, spread and sensi
tivity) at the 2-year follow-up. When characteristics
of pain at baseline were included in the regression
analyses they were relatively strong significant pre
dictors of characteristics of pain after 2 years. After
this adjustment there were fewer socio-demogra
phic and comorbidity predictors; the effect estimates
for those significant predictors had decreased.
Conclusion: Clinical assessment should focus on
several characteristics of pain and include a broad
medical screening to capture the overall burden of
pain in adults from a longitudinal perspective.
Key words: general population; follow-up; chronic pain cha-
racteristics; sociodemographic; comorbidities.
Accepted Jan 3, 2019; Epub ahead of print Feb 27, 2019
J Rehabil Med 2019; 51: 183–192
Correspondence address: Britt Larsson, Pain and Rehabilitation Medi-
cine, Department of Medical and Health Sciences (IMH), Faculty of
Medicine and Health Sciences, Linköping University, SE-581 85 Linkö-
ping. E-mail: [email protected]
A
pproximately 20% of the European population
have moderate to severe chronic pain (CP) (> 3
months) (1), hence it is important to elucidate the
trajectory of CP and determine which factors affect
this trajectory.
LAY ABSTRACT
This study shows how characteristics of chronic pain (in-
tensity, spread and sensitivity) can be predicted using
demographic and socioeconomic factors and other med-
ical conditions. Information was collected from 34,000
individuals between 18 and 85 years of age in south-
eastern Sweden. Several socio-demographic factors and
other medical conditions were predictors of pain inten-
sity, spread and sensitivity after 2 years. When pain
characteristics were taken into consideration in the ana-
lysis they were relatively strong predictors of the pain
characteristics after 2 years. After modification of the
analysis, there were fewer socio-demographic and med-
ical predictors and their importance had decreased. In
planning treatment and rehabilitation for chronic pain,
pain intensity, spread and sensitivity should specifically
be taken into account.
Longitudinal studies have investigated how CP
itself, socio-demographic factors and comorbidities
impact CP over time (2–8); however, the results of
those studies often do not agree, and do not cover
all important characteristics of pain. Some studies
have predicted the presence of chronic widespread
pain and/or spreading (of pain on the body) (2, 4–6).
Other studies have predicted new onset of CP (3). Li-
kewise, pain intensity (severity rated by the subject on
a numeric scale) and pain sensitivity (increased pain
responsiveness to noxious and/or non-noxious stimuli)
are important aspects that contribute to the clinical
presentation of CP (9, 10). Together with physical and
emotional functions, comorbidities, coping strategies,
and quality of life aspects, these characteristics of pain
should be taken into account when elucidating the
impact of pain (11–14).
Previous cross-sectional epidemiological studies
have found that socio-demographic factors, such as
age, sex, marital status, educational level and low
income (15, 16), are associated with CP (i.e. duration
> 3 months).
Recent longitudinal studies have investigated the
importance of some comorbidities, e.g. anxiety, de-
pression, sleeping difficulties, body mass index (BMI)
(2–6), or used an index for comorbidities (4). However,
other comorbidities, e.g. heart disease, hypertension,
diabetes and pulmonary disease, have also been as-
This is an open access article under the CC BY-NC license. www.medicaljournals.se/jrm
Journal Compilation © 2019 Foundation of Rehabilitation Information. ISSN 1650-1977
doi: 10.2340/16501977-2519