The epidemiology of psoriatic arthritis in the UK: a health intelligence analysis of UK Primary Care Electronic Health Records 1991-2020.

OBJECTIVES: Epidemiological estimates of psoriatic arthritis (PsA) underpin the provision of healthcare, research, and the work of government, charities and patient organizations. Methodological problems impacting prior estimates include small sample sizes, incomplete case ascertainment, and representativeness. We developed a statistical modelling strategy to provide contemporary prevalence and incidence estimates of PsA from 1991 to 2020 in the UK. METHODS: Data from Clinical Practice Research Datalink (CPRD) were used to identify cases of PsA between 1st January 1991 and 31st December 2020. To optimize ascertainment, we identified cases of Definite PsA (≥1 Read code for PsA) and Probable PsA (satisfied a bespoke algorithm). Standardized annual rates were calculated using Bayesian multilevel regression with post-stratification to account for systematic differences between CPRD data and the UK population, based on age, sex, socioeconomic status and region of residence. RESULTS: A total of 26293 recorded PsA cases (all definitions) were identified within the study window (77.9% Definite PsA). Between 1991 and 2020 the standardized prevalence of PsA increased twelve-fold from 0.03 to 0.37. The standardized incidence of PsA per 100,000 person years increased from 8.97 in 1991 to 15.08 in 2020, an almost 2-fold increase. Over time, rates were similar between the sexes, and across socioeconomic status. Rates were strongly associated with age, and consistently highest in Northern Ireland. CONCLUSION: The prevalence and incidence of PsA recorded in primary care has increased over the last three decades. The modelling strategy presented can be used to provide contemporary prevalence estimates for musculoskeletal disease using routinely collected primary care data.

Remote sampling of biomarkers of inflammation with linked patient generated health data in patients with rheumatic and musculoskeletal diseases: an Ecological Momentary Assessment feasibility study.

BACKGROUND: People with rheumatic diseases experience troublesome fluctuations in fatigue. Debated causes include pain, mood and inflammation. To determine the relationships between these potential causes, serial assessments are required but are methodologically challenging. This mobile health (mHealth) study explored the viability of using a smartphone app to collect patient-reported symptoms with contemporaneous Dried Blood Spot Sampling (DBSS) for inflammation. METHODS: Over 30 days, thirty-eight participants (12 RA, 13 OA, and 13 FM) used uMotif, a smartphone app, to report fatigue, pain and mood, on 5-point ordinal scales, twice daily. Daily DBSS, from which C-reactive Protein (CRP) values were extracted, were completed on days 1-7, 14 and 30. Participant engagement was determined based on frequency of data entry and ability to calculate within- and between-day symptom changes. DBSS feasibility and engagement was determined based on the proportion of samples returned and usable for extraction, and the number of days between which between-day changes in CRP which could be calculated (days 1-7). RESULTS: Fatigue was reported at least once on 1085/1140 days (95.2%). Approximately 65% of within- and between-day fatigue changes could be calculated. Rates were similar for pain and mood. A total of 287/342 (83.9%) DBSS, were returned, and all samples were viable for CRP extraction. Fatigue, pain and mood varied considerably, but clinically meaningful (≥ 5 mg/L) CRP changes were uncommon. CONCLUSIONS: Embedding DBSS in mHealth studies will enable researchers to obtain serial symptom assessments with matched biological samples. This provides exciting opportunities to address hitherto unanswerable questions, such as elucidating the mechanisms of fatigue fluctuations.

Sleep Disturbance and Quality of Life in Rheumatoid Arthritis: Prospective mHealth Study.

BACKGROUND: Sleep disturbances and poor health-related quality of life (HRQoL) are common in people with rheumatoid arthritis (RA). Sleep disturbances, such as less total sleep time, more waking periods after sleep onset, and higher levels of nonrestorative sleep, may be a driver of HRQoL. However, understanding whether these sleep disturbances reduce HRQoL has, to date, been challenging because of the need to collect complex time-varying data at high resolution. Such data collection is now made possible by the widespread availability and use of mobile health (mHealth) technologies. OBJECTIVE: This mHealth study aimed to test whether sleep disturbance (both absolute values and variability) causes poor HRQoL. METHODS: The quality of life, sleep, and RA study was a prospective mHealth study of adults with RA. Participants completed a baseline questionnaire, wore a triaxial accelerometer for 30 days to objectively assess sleep, and provided daily reports via a smartphone app that assessed sleep (Consensus Sleep Diary), pain, fatigue, mood, and other symptoms. Participants completed the World Health Organization Quality of Life-Brief (WHOQoL-BREF) questionnaire every 10 days. Multilevel modeling tested the relationship between sleep variables and the WHOQoL-BREF domains (physical, psychological, environmental, and social). RESULTS: Of the 268 recruited participants, 254 were included in the analysis. Across all WHOQoL-BREF domains, participants' scores were lower than the population average. Consensus Sleep Diary sleep parameters predicted the WHOQoL-BREF domain scores. For example, for each hour increase in the total time asleep physical domain scores increased by 1.11 points (ß=1.11, 95% CI 0.07-2.15) and social domain scores increased by 1.65 points. These associations were not explained by sociodemographic and lifestyle factors, disease activity, medication use, anxiety levels, sleep quality, or clinical sleep disorders. However, these changes were attenuated and no longer significant when pain, fatigue, and mood were included in the model. Increased variability in total time asleep was associated with poorer physical and psychological domain scores, independent of all covariates. There was no association between actigraphy-measured sleep and WHOQoL-BREF. CONCLUSIONS: Optimizing total sleep time, increasing sleep efficiency, decreasing sleep onset latency, and reducing variability in total sleep time could improve HRQoL in people with RA.

Maintaining musculoskeletal health using a behavioural therapy approach: a population-based randomised controlled trial (the MAmMOTH Study).

OBJECTIVE: Cognitive-behavioural therapy (CBT) has been shown to be effective in the management of chronic widespread pain (CWP); we now test whether it can prevent onset among adults at high risk. METHODS: A population-based randomised controlled prevention trial, with recruitment through UK general practices. A mailed screening questionnaire identified adults at high risk of CWP. Participants received either usual care (UC) or a short course of telephone CBT (tCBT). The primary outcome was CWP onset at 12 months assessed by mailed questionnaire. There were seven secondary outcomes including quality of life (EuroQol Questionnaire-five dimensions-five levels/EQ-5D-5L) used as part of a health economic assessment. RESULTS: 996 participants were randomised and included in the intention-to-treat analysis of which 825 provided primary outcome data. The median age of participants was 59 years; 59% were women. At 12 months there was no difference in the onset of CWP (tCBT: 18.0% vs UC: 17.5%; OR 1.05; 95% CI 0.75 to 1.48). Participants who received tCBT were more likely to report better quality of life (EQ-5D-5L utility score mean difference 0.024 (95% CI 0.009 to 0.040)); and had 0.023 (95% CI 0.007 to 0.039) more quality-adjusted life-years at an additional cost of £42.30 (95% CI -£451.19 to £597.90), yielding an incremental cost-effectiveness ratio of £1828. Most secondary outcomes showed significant benefit for the intervention. CONCLUSIONS: A short course of tCBT did not prevent onset of CWP in adults at high risk, but improved quality of life and was cost-effective. A low-cost, short-duration intervention benefits persons at risk of CWP. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT02668003).

Adolescents' experiences of fluctuating pain in musculoskeletal disorders: a qualitative systematic review and thematic synthesis.

BACKGROUND: Adolescents with chronic musculoskeletal pain experience daily fluctuations in pain. Although not all fluctuations are bothersome, pain flares are a distinct type of symptom fluctuation with greater impact. Since literature on the experience of pain flares is non-existent, the aim of this review was to (i) synthesise the qualitative literature on adolescents' experiences of fluctuating pain in musculoskeletal disorders in order to (ii) identify knowledge gaps to inform future research on pain flares. METHODS: Electronic databases (CINAHL, MEDLINE, EMBASE, PsycINFO), grey literature and reference lists were searched from inception to June 2018 for qualitative studies reporting adolescents' experiences of pain. Comprehensiveness of reporting was assessed using the Consolidated Criteria for Reporting Qualitative Health Research. Studies were analysed using thematic synthesis. RESULTS: Of the 3787 records identified, 32 studies (n = 536) were included. Principal findings were synthesised under three key themes: 1) symptom experience, 2) disruption and loss, and 3) regaining control. The first theme (symptom experience) describes adolescent's perception and interpretation of pain fluctuations. The second theme (disruption and loss) describes the physical, social and emotional constraints faced as a result of changes in pain. The third theme (regaining control) describes coping strategies used to resist and accommodate unpredictable phases of pain. Each theme was experienced differently depending on adolescents' characteristics such as their developmental status, pain condition, and the duration of the pain experience. CONCLUSIONS: Adolescents with chronic musculoskeletal pain live with a daily background level of symptoms which frequently fluctuate and are associated with functional and emotional difficulties. It was not clear whether these symptoms and challenges were experienced as part of 'typical' fluctuations in pain, or whether they reflect symptom exacerbations classified as 'flares'. Further research is needed to explore the frequency and characteristics of pain flares, and how they differ from their typical fluctuations in pain. The review also highlights areas relating to the pain experience, symptom management and health service provision that require further exploration to support more personalised, tailored care for adolescents with chronic musculoskeletal pain.

Central sensitization predicts greater fatigue independently of musculoskeletal pain.

OBJECTIVES: To test whether central sensitization was associated with greater fatigue, independently of musculoskeletal pain. METHODS: 2477 prospective cohort study participants completed a baseline questionnaire comprising the Chalder Fatigue Scale (CFQ), pain, demographics, physical activity, anxiety, depression and medication use. In a clinical assessment of 290 (11.7%) participants, central sensitization was measured by the wind-up ratio test at the hand (WUR-H) and foot (WUR-F). Bioelectric impedance determined proportion body fat. All participants were followed up 12 months later, at which time they completed the CFQ. Linear regression, with inverse probability sampling weights, tested the relationship between WUR at baseline and CFQ at 12 months, adjusted for baseline CFQ, demographics, lifestyle factors, mental health and baseline pain. RESULTS: At baseline, the median interquartile range WUR-H and WUR-F were similar (2.3 (1.5, 4.0) and 2.4 (1.6, 3.9) respectively) and did not differ by sex (difference WUR-H: -0.29, 95% confidence interval -1.28-0.71; WUR-F: -0.57 (-1.50-0.36) or age(WUR-H: -0.53, -1.49-0.43; WUR-F:-0.08, -0.98-0.82). WUR-H scores (ß = 0.11, 95% confidence interval: 0.07-0.16) and WUR-F scores (0.13, 0.08-0.17) were positively associated with CFQ scores at follow-up, independently of baseline CFQ and other covariates. These associations were not explained by baseline pain. CONCLUSION: Fatigue was predicted by central sensitization, independently of the presence of pain. For those seeking to treat fatigue, the benefit of interventions that reduce central sensitization should be investigated.

Evidence for strategies that improve recruitment and retention of adults aged 65 years and over in randomised trials and observational studies: a systematic review.

Background: adults aged ≥65 years are often excluded from health research studies. Lack of representation reduces generalisability of treatments for this age group. Objective: to evaluate the effectiveness of strategies that improve recruitment and retention of adults aged ≥65 in observational studies and randomised controlled trials (RCTs). Methods: searches conducted in 10 databases for RCTs of recruitment and retention strategies in RCTs or observational studies. Two reviewers screened abstracts and full-text articles for eligibility and extracted data. Studies without separate data for adults aged ≥65 were discarded. Risk of bias assessed using the Cochrane Risk of Bias tool. Results were synthesised narratively. Results: thirty-two studies were included in the review (n = 75,444). Twelve studies had low risk of bias, of which 10 had successful strategies including: Opt-out versus opt-in increased recruitment (13.6% (n = 261)-18.7% (n = 36) difference; two studies); Advance notification increased retention (1.6% difference, OR 1.45; 95% CI 1.01, 2.10, one study (n = 2,686); 9.1% difference at 4 months, 1.44; 1.08, 1.92, one study (n = 753)); Hand-delivered versus postal surveys increased response (25.1% difference; X2 = 11.40, P < 0.01; one study (n = 139)); Open randomised design versus blinded RCT increased recruitment (1.56; 1.05, 2.33) and retention (13.9% difference; 3.1%, 24.6%) in one study (n = 538). Risk of bias was high/unclear for studies in which incentives or shorter length questionnaires increased response. Discussion: in low risk of bias studies, few of the strategies that improved participation in older adults had been tested in ≥1 study. Opt-out and advance notification strategies improved recruitment and retention, respectively, although an opt-out approach may have ethical limitations. Evidence from single studies limits the generalisability of other strategies.

Musculoskeletal pain and co-morbid insomnia in adults; a population study of the prevalence and impact on restricted social participation.

BACKGROUND: Comorbidity is common in patients consulting in primary care. Musculoskeletal pain and insomnia each increase the risk of the other. Co-occurrence may pose an increased burden on well-being. However, the prevalence and impact of co-existing pain and insomnia in adults living in the community who may present to primary care is unclear. The aim of this study was to report the prevalence of pain and insomnia in adults registered with primary care, and to examine the impact of co-occurrence on social activities. METHODS: This population-based prospective cohort study of adults aged ≥18 years (n = 1181) used health survey data collected via baseline and 12 month follow-up questionnaires. Baseline data on pain, insomnia (4 symptoms: delayed sleep onset, difficulty maintaining sleep, early waking and non-restorative sleep) and putative confounders and social activity restriction at follow up was collected. Associations between baseline pain, insomnia and restricted social activities (RSA) at 12 months were examined using logistic regression, with adjustment for confounders. Interaction terms between pain and each insomnia symptom were examined in final models. RESULTS: Mean respondent age was 49.6 (SD ± 15.2) years, 55.7% were female. At baseline, 880 (74.5%) reported pain, 122 (10.3%) delayed sleep onset, 298 (25.2%) difficulty maintaining sleep, 188 (15.9%) early wakening, and 215 (18.2%) reported non-restorative sleep. At follow-up 200 (16.9%) reported RSA. Pain and each insomnia symptom were associated with RSA at 12 month follow-up; pain [unadjusted odds ratio (OR:2.3;95%CI:1.5,3.5), delayed sleep onset (OR:6.1;95%CI:4.0,9.1), difficulty maintaining sleep (OR:3.2;95%CI:2.3,4.4), early wakening (OR:4.1;95%CI:2.9,5.9), and non-restorative sleep (OR:4.0; 95%CI:2.8,5.8). Only delayed sleep onset (OR:2.6;95%C:1.5,4.5) remained significantly associated with restricted social activities in the fully adjusted model. There was a significant interaction between pain and delayed sleep onset (OR:0.3;95%CI:0.1,0.99; p = .049) and restricted social activity at 12 months in the final multivariable model. CONCLUSIONS: Pain and insomnia commonly co-occur, resulting in greater impact upon subsequent functional ability. Delayed sleep onset is the insomnia symptom most strongly associated with reduced functional ability. Clinicians should be aware of the common co-occurrence of insomnia symptoms, inquire about sleep in patients consulting with pain, and offer interventions that target both sleep and pain.

Chronic widespread pain is associated with worsening frailty in European men.

BACKGROUND: we hypothesised that chronic widespread pain (CWP), by acting as a potential stressor, may predispose to the development of, or worsening, frailty. SETTING: longitudinal analysis within the European Male Ageing Study (EMAS). PARTICIPANTS: a total of 2,736 community-dwelling men aged 40-79. METHODS: subjects completed a pain questionnaire and shaded a manikin, with the presence of CWP defined using the American College of Rheumatology criteria. Physical activity, smoking, alcohol consumption and depression were measured. Repeat assessments took place a median of 4.3 years later. A frailty index (FI) was used, with frail defined as an FI >0.35. The association between CWP at baseline and the new occurrence of frailty was examined using logistic regression; the association between CWP at baseline and change in FI was examined using negative binomial regression. RESULTS: at baseline, 218 (8.3%) men reported CWP. Of the 2,631 men who were defined as non-frail at baseline, 112 (4.3%) were frail at follow-up; their mean FI was 0.12 (SD 0.1) at baseline and 0.15 (SD 0.1) at follow-up, with a mean change of 0.03 (SD 0.08) P ≤ 0.001. Among men who were non-frail at baseline, those with CWP were significantly more likely to develop frailty. After adjustment for age and centre, compared with those with no pain, those with CWP at baseline had a 70% higher FI at follow-up; these associations remained significant after further adjustment for smoking, body mass index, depression, physical activity and FI at baseline. CONCLUSION: the presence of CWP is associated with an increased risk of frailty in older European men.

Managing chronic widespread pain in primary care: a qualitative study of patient perspectives and implications for treatment delivery.

BACKGROUND: Clinical guidelines recommend a combination of physical, pharmacological and psychological treatments for chronic widespread pain, but published accounts of treatment acceptability are lacking. METHODS: Semi-structured interviews (n = 44) nested within a randomised controlled trial comparing the clinical and cost effectiveness of prescribed exercise, cognitive behavioural therapy (CBT), and combined exercise and CBT to treatment as usual for adults with chronic widespread pain. RESULTS: Three main themes emerged from the data: i) the illness context (how people experience chronic pain and associated health services); ii) the identity context (how people react to their symptoms and accommodate these within themselves) and iii) the intervention context (the extent and manner by which the trial interventions models aligned with these responses). Referral to a prescribed exercise programme resonated most closely with participants' tendency to attribute pain to a structural or mechanical defect. Psychological therapy brought with it connotations of social judgement, deviance and stigma. Experience of psychological therapy often exceeded expectation. Participants who engaged in cognitive reflection and behavioural adaptation reported an upward identity shift independent of increased physical exercise behaviour. CONCLUSIONS: A logical rationale for a health intervention is in itself insufficient to ensure uptake and participation. Potential differences in treatment meaning emphasise the importance of acknowledging different phases of illness acceptance and of providing the most appropriate treatment option for the stage of reconciliation. Health service providers must not only understand people's own perceptions of chronic widespread pain but also the broader spheres of influence in which this pain is experienced.

The Maintaining Musculoskeletal Health (MAmMOTH) Study: Protocol for a randomised trial of cognitive behavioural therapy versus usual care for the prevention of chronic widespread pain.

BACKGROUND: Cognitive behavioural therapy (CBT) has been shown to improve outcomes for patients with fibromyalgia, and its cardinal feature chronic widespread pain (CWP). Prediction models have now been developed which identify groups who are at high-risk of developing CWP. It would be beneficial to be able to prevent the development of CWP in these people because of the high cost of symptoms and because once established they are difficult to manage. We will test the hypothesis that among patients who are identified as at high-risk, a short course of telephone-delivered CBT (tCBT) reduces the onset of CWP. We will further determine the cost-effectiveness of such a preventative intervention. METHODS: The study will be a two-arm randomised trial testing a course of tCBT against usual care for prevention of CWP. Eligible participants will be identified from a screening questionnaire sent to patients registered at general practices within three Scottish health boards. Those returning questionnaires indicating they have visited their doctor for regional pain in the last 6 months, and who have two of, sleep problems, maladaptive behaviour response to illness, or high number of somatic symptoms, will be invited to participate. After giving consent, participants will be randomly allocated to either tCBT or usual care. We aim to recruit 473 participants to each treatment arm. Participants in the tCBT group will have an initial assessment with a CBT therapist by telephone, then 6 weekly sessions, and booster sessions 3 and 6 months after treatment start. Those in the usual care group will receive no additional intervention. Follow-up questionnaires measuring the same items as the screening survey questionnaire will be sent 3, 12 and 24 months after start of treatment. The main outcome will be CWP at the 12 month questionnaire. DISCUSSION: This will be the first trial of an intervention aimed at preventing fibromyalgia or CWP. The results of the study will help to inform future treatments for the prevention of chronic pain, and aetiological models of its development. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT02668003URL: Please check that the following URLs are working. If not, please provide alternatives: NCT02668003Alternative is: https://www.clinicaltrials.gov/ct2/show/NCT02668003> . Date registered: 28-Jan-2016.

Impact of musculoskeletal pain on insomnia onset: a prospective cohort study.

OBJECTIVE: Pain, the most common manifestation of rheumatological conditions, is highly prevalent among older adults, with worse health outcomes found in those with co-morbid insomnia. Proactive prevention of insomnia may reduce the overall disease burden of pain and rheumatological conditions. To inform such development, this study examined the role of pain, physical limitation and reduced social participation in predicting and mediating insomnia onset. METHODS: A prospective cohort study was conducted involving 6676 individuals ≥50 years of age who completed questionnaires at baseline and a 3-year follow-up. Participants were classified into none, some and widespread pain according to the ACR criteria. Logistic regression was used to examine the relationship between baseline pain and insomnia onset at 3 years. Path analysis was used to test for the mediating role of physical limitation and social participation restriction. RESULTS: Some [adjusted odds ratio (AOR) 1.57 (95% CI 1.15, 2.13)] and widespread [2.13 (1.66, 3.20)] pain increased the risk of insomnia onset at 3 years, after adjusting for age, gender, socio-economic class, education, anxiety, depression, sleep and co-morbidity at baseline. The combination of physical limitation and reduced social participation explained up to 68% of the effect of some pain on insomnia onset and 66% of the effect of widespread pain on insomnia onset. CONCLUSION: There was a dose-response association between the extent of pain at baseline and insomnia onset at 3 years that was substantially mediated by physical limitation and reduced social participation. Targeting physical limitation and social participation in older people with pain may buffer co-morbid insomnia, reducing the overall disease burden.

The influence of behavioural and psychological factors on medication adherence over time in rheumatoid arthritis patients: a study in the biologics era.

OBJECTIVES: To investigate levels of self-reported adherence to biologic treatment and establish the contribution of demographic, physical and psychological factors to biologic medication adherence in an RA cohort. METHODS: Adalimumab-treated patients were recruited through the British Society for Rheumatology Biologics Register for RA between May 2007 and April 2009. Demographic and baseline psychological measures including illness and medication beliefs were collected. Disease activity (28-item DAS), physical function (HAQ) and quality of life (36-item Short Form Health Survey) were also measured at baseline and at 6, 12 and 18 months. Adherence was assessed at each follow-up using the patient self-completed Compliance Questionnaire for Rheumatology (CQR). Multilevel mixed effects modelling analysis was performed to investigate predictors of adherence. RESULTS: Of the 329 Adalimumab-treated patients included, low adherence (CQR score <65) was reported in 23%, with 41% reporting low adherence at at least one time point. After controlling for age and disease duration, factors independently predictive of increased adherence were increased belief in medication necessity, with baseline effect diminishing over time [ß coefficient 1.68 (s.e. 0.19), P = 0.0001], lower medication concerns [0.50 (0.15), P = 0.001], with this effect remaining throughout follow-up, increased professional or family member support [0.81 (0.32), P = 0.01], strong views of illness being chronic [0.32 (0.14), P = 0.025] and increased treatment control [0.41 (0.19), P = 0.032]. CONCLUSION: Wider recognition of the importance of psychological factors, particularly medication beliefs, in driving medication adherence could have substantial clinical and health economic benefits in RA. The psychological factors we have identified are putative targets for strategies to improve adherence in RA.

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.

Delivering an Optimised Behavioural Intervention (OBI) to people with low back pain with high psychological risk; results and lessons learnt from a feasibility randomised controlled trial of Contextual Cognitive Behavioural Therapy (CCBT) vs. Physiotherapy.

BACKGROUND: Low Back Pain (LBP) remains a common and costly problem. Psychological obstacles to recovery have been identified, but psychological and behavioural interventions have produced only moderate improvements. Reviews of trials have suggested that the interventions lack clear theoretical basis, are often compromised by low dose, lack of fidelity, and delivery by non-experts. In addition, interventions do not directly target known risk mechanisms. We identified a theory driven intervention (Contexual Cognitive Behavioural Therapy, CCBT) that directly targets an evidence-based risk mechanism (avoidance and ensured dose and delivery were optimised. This feasibility study was designed to test the credibility and acceptability of optimised CCBT against physiotherapy for avoidant LBP patients, and to test recruitment, delivery of the intervention and response rates prior to moving to a full definitive trial. METHODS: A randomised controlled feasibility trial with patients randomised to receive CCBT or physiotherapy. CCBT was delivered by trained supervised psychologists on a one to one basis and comprised up to 8 one-hour sessions. Physiotherapy comprised back to fitness group exercises with at least 60 % of content exercise-based. Patients were eligible to take part if they had back pain for more than 3 months, and scored above a threshold indicating fear avoidance, catastrophic beliefs and distress. RESULTS: 89 patients were recruited. Uptake rates were above those predicted. Scores for credibility and acceptability of the interventions met the set criteria. Response rates at three and six months fell short of the 75 % target. Problems associated with poor response rates were identified and successfully resolved, rates increased to 77 % at 3 months, and 68 % at 6 months. Independent ratings of treatment sessions indicated that CCBT was delivered to fidelity. Numbers were too small for formal analysis. Although average scores for acceptance were higher in the CCBT group than in the group attending physiotherapy (increase of 7.9 versus 5.1) and change in disability and pain from baseline to 6 months were greater in the CCBT group than in the physiotherapy group, these findings should be interpreted with caution. CONCLUSIONS: CCBT is a credible and acceptable intervention for LBP patients who exhibit psychological obstacles to recovery. TRIAL REGISTRATION: ISRCTN43733490 , registered 15/12/2010.

Pain at multiple body sites and health-related quality of life in older adults: results from the North Staffordshire Osteoarthritis Project.

OBJECTIVES: Number of pain sites (NPS) is a potentially important marker of health-related quality of life (HRQoL) but remains unexplored in older people. This cross-sectional study investigated whether, in older people including the oldest old, NPS was independently associated with poorer mental and physical HRQoL and if the association was moderated by age. METHODS: A postal questionnaire sent to a population sample of adults aged ≥50 years in North Staffordshire, UK, included the 12-item Short Form Health Survey (SF-12) mental component summary (MCS) and physical component summary (PCS), a blank body pain manikin, socio-demographic, health behaviour and morbidity questions. Participants shaded sites of pain lasting ≥1 day in the past 4 weeks on the manikin. OA consultation data were obtained for participants consenting to medical records review. RESULTS: A total of 13 986 individuals (adjusted response 70.6%) completed a questionnaire, of which 12 408 provided complete pain data. The median NPS reported was 4 [interquartile range (IQR) 0-8]. General linear models showed that an increasing NPS was significantly associated with poorer MCS (ß = -0.43, 95% CI -0.46, -0.40) and PCS (ß = -0.87, 95% CI -0.90, -0.84). Adjustment for covariates attenuated the associations but they remained significant ( MCS: ß = -0.28, 95% CI -0.31, -0.24; PCS: ß = -0.63, 95% CI -0.66, -0.59). The association between NPS and MCS or PCS was moderated by age, but the strongest associations were not in the oldest old. CONCLUSION: NPS appears to be a potentially modifiable target for improving physical and mental HRQoL in older people. Future analyses should investigate the influence of NPS on HRQoL over time in older people.

Identifying Weekly Trajectories of Pain Severity Using Daily Data From an mHealth Study: Cluster Analysis.

BACKGROUND: People with chronic pain experience variability in their trajectories of pain severity. Previous studies have explored pain trajectories by clustering sparse data; however, to understand daily pain variability, there is a need to identify clusters of weekly trajectories using daily pain data. Between-week variability can be explored by quantifying the week-to-week movement between these clusters. We propose that future work can use clusters of pain severity in a forecasting model for short-term (eg, daily fluctuations) and longer-term (eg, weekly patterns) variability. Specifically, future work can use clusters of weekly trajectories to predict between-cluster movement and within-cluster variability in pain severity. OBJECTIVE: This study aims to understand clusters of common weekly patterns as a first stage in developing a pain-forecasting model. METHODS: Data from a population-based mobile health study were used to compile weekly pain trajectories (n=21,919) that were then clustered using a k-medoids algorithm. Sensitivity analyses tested the impact of assumptions related to the ordinal and longitudinal structure of the data. The characteristics of people within clusters were examined, and a transition analysis was conducted to understand the movement of people between consecutive weekly clusters. RESULTS: Four clusters were identified representing trajectories of no or low pain (1714/21,919, 7.82%), mild pain (8246/21,919, 37.62%), moderate pain (8376/21,919, 38.21%), and severe pain (3583/21,919, 16.35%). Sensitivity analyses confirmed the 4-cluster solution, and the resulting clusters were similar to those in the main analysis, with at least 85% of the trajectories belonging to the same cluster as in the main analysis. Male participants spent longer (participant mean 7.9, 95% bootstrap CI 6%-9.9%) in the no or low pain cluster than female participants (participant mean 6.5, 95% bootstrap CI 5.7%-7.3%). Younger people (aged 17-24 y) spent longer (participant mean 28.3, 95% bootstrap CI 19.3%-38.5%) in the severe pain cluster than older people (aged 65-86 y; participant mean 9.8, 95% bootstrap CI 7.7%-12.3%). People with fibromyalgia (participant mean 31.5, 95% bootstrap CI 28.5%-34.4%) and neuropathic pain (participant mean 31.1, 95% bootstrap CI 27.3%-34.9%) spent longer in the severe pain cluster than those with other conditions, and people with rheumatoid arthritis spent longer (participant mean 7.8, 95% bootstrap CI 6.1%-9.6%) in the no or low pain cluster than those with other conditions. There were 12,267 pairs of consecutive weeks that contributed to the transition analysis. The empirical percentage remaining in the same cluster across consecutive weeks was 65.96% (8091/12,267). When movement between clusters occurred, the highest percentage of movement was to an adjacent cluster. CONCLUSIONS: The clusters of pain severity identified in this study provide a parsimonious description of the weekly experiences of people with chronic pain. These clusters could be used for future study of between-cluster movement and within-cluster variability to develop accurate and stakeholder-informed pain-forecasting tools.

Reliability, validity, and responsiveness of a smartphone-based manikin to support pain self-reporting.

Introduction: Many people worldwide suffer from chronic pain. Improving our knowledge on chronic pain prevalence and management requires methods to collect pain self-reports in large populations. Smartphone-based tools could aid data collection by allowing people to use their own device, but the measurement properties of such tools are largely unknown. Objectives: To assess the reliability, validity, and responsiveness of a smartphone-based manikin to support pain self-reporting. Methods: We recruited people with fibromyalgia, rheumatoid arthritis, and/or osteoarthritis and access to a smartphone and the internet. Data collection included the Global Pain Scale at baseline and follow-up, and 30 daily pain drawings completed on a 2-dimensional, gender-neutral manikin. After deriving participants' pain extent from their manikin drawings, we evaluated convergent and discriminative validity, test-retest reliability, and responsiveness and assessed findings against internationally agreed criteria for good measurement properties. Results: We recruited 131 people; 104 were included in the full sample, submitting 2185 unique pain drawings. Manikin-derived pain extent had excellent test-retest reliability (intraclass correlation coefficient, 0.94), moderate convergent validity (ρ, 0.46), and an ability to distinguish fibromyalgia and osteoarthritis from rheumatoid arthritis (F statistics, 30.41 and 14.36, respectively; P < 0.001). Responsiveness was poor (ρ, 0.2; P, 0.06) and did not meet the respective criterion for good measurement properties. Conclusion: Our findings suggest that smartphone-based manikins can be a reliable and valid method for pain self-reporting, but that further research is warranted to explore, enhance, and confirm the ability of such manikins to detect a change in pain over time.

How well can we measure chronic pain impact in existing longitudinal cohort studies? Lessons learned.

Multiple large longitudinal cohorts provide opportunities to address questions about predictors of pain and pain trajectories, even when not anticipated in design of the historical databases. This focus article uses two empirical examples to illustrate the processes of assessing the measurement properties of data from large cohort studies to answer questions about pain. In both examples, data were screened to select candidate variables that captured the impact of chronic pain on self-care activities, productivity and social activities. We describe a series of steps to select candidate items and evaluate their psychometric characteristics in relation to the measurement of pain impact proposed. In UK Biobank, a general lack of internal consistency of variables selected prevented the identification of a satisfactory measurement model, with lessons for the measurement of chronic pain impact. In the English Longitudinal Study of Ageing, a measurement model for chronic pain impact was identified, albeit limited to capturing the impact of pain on self-care and productivity but lacking coverage related to social participation. In conjunction with its supplementary material, this focus article aims to encourage exploration of these valuable prospectively collected data; to support researchers to make explicit the relationships between items in the databases and constructs of interest in pain research; and to use empirical methods to estimate the possible biases in these variables. PERSPECTIVE: This focus article outlines a theory-driven approach for fitting new measurement models to data from large cohort studies, and evaluating their psychometric properties. This aims to help researchers develop an empirical understanding of the gains and limitations connected with the process of re-purposing the data stored in these datasets.

Users' views on the use of a smartwatch app to collect daily symptom data in individuals with multiple long-term conditions (Multimorbidity): A qualitative study.

Introduction: Long-term conditions are a major burden on health systems. One way to facilitate more research and better clinical care among patients with long-term conditions is to collect accurate data on their daily symptoms (patient-generated health data) using wearable technologies. Whilst evidence is growing for the use of wearable technologies in single conditions, there is less evidence of the utility of frequent symptom tracking in those who have more than one condition. Aims: To explore patient views of the acceptability of collecting daily patient-generated health data for three months using a smartwatch app. Methods: Watch Your Steps was a longitudinal study which recruited 53 patients to track over 20 symptoms per day for a 90-day period using a study app on smartwatches. Semi-structured interviews were conducted with a sub-sample of 20 participants to explore their experience of engaging with the app. Results: In a population of older people with multimorbidity, patients were willing and able to engage with a patient-generated health data app on a smartwatch. It was suggested that to maintain engagement over a longer period, more 'real-time' feedback from the app should be available. Participants did not seem to consider the management of more than one condition to be a factor in either engagement or use of the app, but the presence of severe or chronic pain was at times a barrier. Conclusion: This study has provided preliminary evidence that multimorbidity was not a major barrier to engagement with patient-generated health data via a smartwatch symptom tracking app.