Ross Wilkie

The Keele Assessment of Participation: A New Instrument to Measure Participation Restriction in Population Studies. Combined Qualitative and Quantitative Examination of its Psychometric Properties

The World Health Organization has proposed participation restriction to reflect the societal consequences of health conditions. Despite its importance, participation restriction appears to be inconsistently represented or absent from the content of many health status instruments. This paper describes the development and testing of a new self-complete measure of participation restriction from the conceptual basis of participation as an individual’s perception of their actual involvement in life situations. The psychometric properties (face, content and construct validity, responder burden, performance and repeatability) of the instrument were examined using qualitative and quantitative methods. Person-perceived participation restriction did not reflect the frequency of participation but was associated with participants’ expectations, aspirations, and needs, as well as contextual factors. We conclude that the instrument can provide estimates of person-perceived participation restriction in population surveys.

The effect of age on the onset of pain interference in a general population of older adults: prospective findings from the North Staffordshire Osteoarthritis Project (NorStOP).

Abstract Pain that interferes with daily life appears to be strongly age‐related in cross‐sectional studies, although the nature of this relationship over time has not been established. We have investigated the onset and persistence of pain and pain interference over a 3‐year period to determine their association with age in older people. A 3‐year follow‐up postal survey was conducted of adults aged 50 years and over (n = 5366) who had previously been recruited as part of the North Staffordshire Osteoarthritis Project. Four thousand two‐hundred and thirty‐four completed questionnaires were received (adjusted response 84.7%). The occurrence of pain interference at 3 years was 19.7% in persons free of such pain at baseline, higher in females than males (6.0% difference; 95% CI: 2.6%, 9.3%), and showed a clear age‐related trend with a more than twofold increase from 50 to 59 years (16.0%) to the 80+ years (35%). Any pain at follow‐up was reported by 48% of those pain‐free at recruitment, and this figure was similar for males and females, and across 10‐year age‐groups. Persistence of pain interference (72.1%) at 3 years was high. In adults aged 50 years and over, the onset of pain that interferes with life shows a clear gender difference and a consistent rise with age into the oldest age‐group. This was in strong contrast to the onset of pain which showed no gender or age‐related trends. The implications for public health, as for the treatment of the individual, are twofold, relating to efforts to prevent disabling pain from occurring and to understand the factors that accelerate the impact which pain has on everyday life when people reach the oldest ages.

The Knee Clinical Assessment Study – CAS(K). A prospective study of knee pain and knee osteoarthritis in the general population

BackgroundKnee pain affects an estimated 25% of the adult population aged 50 years and over. Osteoarthritis is the most common diagnosis made in older adults consulting with knee pain in primary care. However, the relationship between this diagnosis and both the current disease-based definition of osteoarthritis and the regional pain syndrome of knee pain and disability is unclear. Expert consensus, based on current evidence, views the disease and the syndrome as distinct entities but the clinical usefulness of these two approaches to classifying knee pain in older adults has not been established. We plan to conduct a prospective, population-based, observational cohort study to investigate the relative merits of disease-based and regional pain syndrome-based approaches to classification and prognosis of knee pain in older adults.MethodsAll patients aged 50 years and over registered with three general practices in North Staffordshire will be invited to take part in a two-stage postal survey. Respondents to this survey phase who indicate that they have experienced knee pain within the previous 12 months will be invited to attend a research clinic for a detailed assessment. This will consist of clinical interview, physical examination, digital photography, plain x-rays, anthropometric measurement and a brief self-complete questionnaire. All consenting clinic attenders will be followed up by (i) general practice medical record review, (ii) repeat postal questionnaire at 18-months.

Social risks for disabling pain in older people: A prospective study of individual and area characteristics

&NA; Pain is common in adult life, and the extent to which pain interferes with daily activities rises with age. Little is known about the social factors associated with disabling pain. The objective was to determine the individual and neighbourhood social factors that predict pain that interferes with daily activities. This was a prospective cohort study set within the North Staffordshire Osteoarthritis Project (NorStOP). People aged 50 and over registered with six general practices were sent baseline and 3‐year questionnaires. Individual predictors of the onset of pain interference were determined through multilevel modelling. Neighbourhood impact was examined using measures of deprivation taken from the UK Index of Multiple Deprivation 2004. 19% of the 3644 people without pain interference at baseline reported it at follow‐up. Baseline social factors were weaker predictors than baseline age, multiple‐site pain and anxiety or depression. However, perceived financial strain was a significant predictor (OR 1.5; 95% CI: 1.2, 1.8). Onset of pain interference varied by local area deprivation status. Those living in areas of high health deprivation had an increased risk of developing pain interference (OR 1.6; 95% CI: 1.1, 2.3). Whilst the onset of pain which disrupts daily life is influenced mainly by the characteristics of the pain and by the psychological factors, there are links with the social factors, particularly individual measures of perceived income adequacy. The onset of disabling pain is also influenced by the place where one lives. Policies to prevent disabling pain need to consider the contribution of neighbourhood deprivation and income inequalities to the extent of the problem.

International comparisons of the consultation prevalence of musculoskeletal conditions using population-based healthcare data from England and Sweden

Objectives To assess the consultation prevalence of musculoskeletal (MSK) conditions as presented in different healthcare systems, and to determine the feasibility of comparing prevalence figures between nations. Methods The settings were an English regional database (Consultations in Primary Care Archive (CiPCA)) and the Swedish Skåne County Health Care Register. Case definitions, data extraction and analysis procedures were harmonised. The number of people consulting per 10 000 registered population in primary care, and in primary or secondary care, in the year 2010 (annual consultation prevalence) were determined for doctor-diagnosed osteoarthritis (OA), rheumatoid arthritis (RA), low back pain, and spondyloarthritis including psoriatic arthritis and ankylosing spondylitis (AS). Seven-year period consultation prevalences were also determined. Results Combining primary and secondary care, annual consultation prevalences of any MSK condition (2143 vs 1610/10 000) and low back pain (587 vs 294/10 000) were higher in England than in Sweden, but higher for RA, spondyloarthritis and psoriatic arthritis in Sweden. Annual primary care prevalence figures for OA (176 vs 196/10 000), RA (25 vs 26/10 000), spondyloarthritis (both 8/10 000) and psoriatic arthritis (5 vs 3/10 000) were similar between England and Sweden. AS was rarely recorded in Swedish primary care. These patterns were also observed for 7-year period consultation prevalences. Conclusions A rigorous methodological approach allowed feasible comparison of MSK consultation prevalence between England and Sweden. Differences in prevalence of inflammatory and unspecific pain conditions may be partially explained by known variations in healthcare systems and recording practice. Routine healthcare data offers potential for investigating variations in occurrence and outcome of MSK conditions between nations.

Multiple joint pain and lower extremity disability in middle and old age

Purpose. To determine whether the extent of multiple-site lower extremity joint pain contributes to disability in middle and old age and describe patterns of severity in site-specific measures amongst those with multiple-site pain. Method. Population-based, cross-sectional postal survey. Adults aged 50 years and over registered with three general practices and reporting pain lasting one month or longer in the previous year in at least one hip, knee, or foot were included. Respondents completed a generic measure of physical function and site-specific measures of severity for each relevant joint pain. Results. Of 2429 eligible participants, 1801 reported multiple-site lower limb joint pain. Lower limb joint pain count was independently associated with reduced physical function after adjusting for a range of covariates. The severity of pain and disability attributed to each site increased as the number of painful sites increased. Conclusion. Many older people with joint pain in the lower limb have more than one joint affected. Generic and site-specific measures of disability both show the same pattern of reduced physical function. Treatment targeted at a single joint may have only a marginal effect on reducing disability in individuals with multiple joint involvement unless treatment is also conferring benefit at other sites.

The Knee Clinical Assessment Study – CAS(K). A prospective study of knee pain and knee osteoarthritis in the general population: baseline recruitment and retention at 18 months

BackgroundSelective non-participation at baseline (due to non-response and non-consent) and loss to follow-up are important concerns for longitudinal observational research. We investigated these matters in the context of baseline recruitment and retention at 18 months of participants for a prospective observational cohort study of knee pain and knee osteoarthritis in the general population.MethodsParticipants were recruited to the Knee Clinical Assessment Study – CAS(K) – by a multi-stage process involving response to two postal questionnaires, consent to further contact and medical record review (optional), and attendance at a research clinic. Follow-up at 18-months was by postal questionnaire. The characteristics of responders/consenters were described for each stage in the recruitment process to identify patterns of selective non-participation and loss to follow-up. The external validity of findings from the clinic attenders was tested by comparing the distribution of WOMAC scores and the association between physical function and obesity with the same parameters measured directly in the target population as whole.Results3106 adults aged 50 years and over reporting knee pain in the previous 12 months were identified from the first baseline questionnaire. Of these, 819 consented to further contact, responded to the second questionnaire, and attended the research clinics. 776 were successfully followed up at 18 months. There was evidence of selective non-participation during recruitment (aged 80 years and over, lower socioeconomic group, currently in employment, experiencing anxiety or depression, brief episode of knee pain within the previous year). This did not cause significant bias in either the distribution of WOMAC scores or the association between physical function and obesity.ConclusionDespite recruiting a minority of the target population to the research clinics and some evidence of selective non-participation, this appears not to have resulted in significant bias of cross-sectional estimates. The main effect of non-participation in the current cohort is likely to be a loss of precision in stratum-specific estimates e.g. in those aged 80 years and over. The subgroup of individuals who attended the research clinics and who make up the CAS(K) cohort can be used to accurately estimate parameters in the reference population as a whole. The potential for selection bias, however, remains an important consideration in each subsequent analysis.

Predictors of new-onset widespread pain in older adults: results from a population-based prospective cohort study in the UK.

In older adults, widespread pain (WP) is common, although its etiology is unclear. This study sought to identify factors associated with an increased risk of developing WP in adults age ≥50 years.

Sleep Disturbance and Chronic Widespread Pain

Musculoskeletal pain is common and often occurs at multiple sites. Persons with chronic widespread pain (CWP) often report disturbed sleep. Until recently, the relationship between sleep disturbance and CWP has been unclear: does poor sleep increase the risk of developing CWP, do people with CWP develop poor sleep as a consequence of their pain, or is the relationship bi-directional? In this article, we have focused on the relationship between insomnia and CWP. We briefly present descriptive epidemiological data for insomnia and CWP. We then summarise the available evidence which supports the hypothesis that the relationship is bi-directional. Finally, we discuss the clinical management of CWP and insomnia in primary care, where the vast majority of cases of CWP are managed.

Chronic Pain and Mortality: A Systematic Review

Background Chronic pain is common, often widespread and has a substantial impact on health and quality of life. The relationship between chronic pain and mortality is unclear. This systematic review aimed to identify and evaluate evidence for a relationship between chronic pain and mortality. Methods A search of ten electronic databases including EMBASE and MEDLINE was conducted in March 2012, and updated until March 2014. Observational studies investigating the association between chronic or widespread pain (including fibromyalgia) and mortality were included. Risk of bias was assessed and a meta-analysis was undertaken to quantify heterogeneity and pool results. A narrative review was undertaken to explore similarities and differences between the included studies. Results Ten studies were included in the review. Three reported significant associations between chronic or widespread pain and mortality in unadjusted results. In adjusted analyses, four studies reported a significant association. The remaining studies reported no statistically significant association. A meta-analysis showed statistically significant heterogeneity of results from studies using comparable outcome measures (n = 7)(I2 = 78.8%) and a modest but non-significant pooled estimate (MRR1.14,95%CI 0.95–1.37) for the relationship between chronic pain and all-cause mortality. This association was stronger when analysis was restricted to studies of widespread pain (n = 5,I2 = 82.3%) MRR1.22(95%CI 0.93–1.60). The same pattern was observed with deaths from cancer and cardiovascular diseases. Heterogeneity is likely to be due to differences in study populations, follow-up time, pain phenotype, methods of analysis and use of confounding factors. Conclusion This review showed a mildly increased risk of death in people with chronic pain, particularly from cancer. However, the small number of studies and methodological differences prevented clear conclusions from being drawn. Consistently applied definitions of chronic pain and further investigation of the role of health, lifestyle, social and psychological factors in future studies will improve understanding of the relationship between chronic pain and mortality.