Epidemiological Differences Between Localized and Nonlocalized Low Back Pain.

STUDY DESIGN: A cross-sectional survey with a longitudinal follow-up. OBJECTIVES: The aim of this study was to test the hypothesis that pain, which is localized to the low back, differs epidemiologically from that which occurs simultaneously or close in time to pain at other anatomical sites SUMMARY OF BACKGROUND DATA.: Low back pain (LBP) often occurs in combination with other regional pain, with which it shares similar psychological and psychosocial risk factors. However, few previous epidemiological studies of LBP have distinguished pain that is confined to the low back from that which occurs as part of a wider distribution of pain. METHODS: We analyzed data from CUPID, a cohort study that used baseline and follow-up questionnaires to collect information about musculoskeletal pain, associated disability, and potential risk factors, in 47 occupational groups (office workers, nurses, and others) from 18 countries. RESULTS: Among 12,197 subjects at baseline, 609 (4.9%) reported localized LBP in the past month, and 3820 (31.3%) nonlocalized LBP. Nonlocalized LBP was more frequently associated with sciatica in the past month (48.1% vs. 30.0% of cases), occurred on more days in the past month and past year, was more often disabling for everyday activities (64.1% vs. 47.3% of cases), and had more frequently led to medical consultation and sickness absence from work. It was also more often persistent when participants were followed up after a mean of 14 months (65.6% vs. 54.1% of cases). In adjusted Poisson regression analyses, nonlocalized LBP was differentially associated with risk factors, particularly female sex, older age, and somatizing tendency. There were also marked differences in the relative prevalence of localized and nonlocalized LBP by occupational group. CONCLUSION: Future epidemiological studies should distinguish where possible between pain that is limited to the low back and LBP that occurs in association with pain at other anatomical locations. LEVEL OF EVIDENCE: 2.

Descriptive Epidemiology of Somatising Tendency: Findings from the CUPID Study.

Somatising tendency, defined as a predisposition to worry about common somatic symptoms, is importantly associated with various aspects of health and health-related behaviour, including musculoskeletal pain and associated disability. To explore its epidemiological characteristics, and how it can be specified most efficiently, we analysed data from an international longitudinal study. A baseline questionnaire, which included questions from the Brief Symptom Inventory about seven common symptoms, was completed by 12,072 participants aged 20-59 from 46 occupational groups in 18 countries (response rate 70%). The seven symptoms were all mutually associated (odds ratios for pairwise associations 3.4 to 9.3), and each contributed to a measure of somatising tendency that exhibited an exposure-response relationship both with multi-site pain (prevalence rate ratios up to six), and also with sickness absence for non-musculoskeletal reasons. In most participants, the level of somatising tendency was little changed when reassessed after a mean interval of 14 months (75% having a change of 0 or 1 in their symptom count), although the specific symptoms reported at follow-up often differed from those at baseline. Somatising tendency was more common in women than men, especially at older ages, and varied markedly across the 46 occupational groups studied, with higher rates in South and Central America. It was weakly associated with smoking, but not with level of education. Our study supports the use of questions from the Brief Symptom Inventory as a method for measuring somatising tendency, and suggests that in adults of working age, it is a fairly stable trait.

Classification of neck/shoulder pain in epidemiological research: a comparison of personal and occupational characteristics, disability, and prognosis among 12,195 workers from 18 countries.

To inform case definition for neck/shoulder pain in epidemiological research, we compared levels of disability, patterns of association, and prognosis for pain that was limited to the neck or shoulders (LNSP) and more generalised musculoskeletal pain that involved the neck or shoulder(s) (GPNS). Baseline data on musculoskeletal pain, disability, and potential correlates were collected by questionnaire from 12,195 workers in 47 occupational groups (mostly office workers, nurses, and manual workers) in 18 countries (response rate = 70%). Continuing pain after a mean interval of 14 months was ascertained through a follow-up questionnaire in 9150 workers from 45 occupational groups. Associations with personal and occupational factors were assessed by Poisson regression and summarised by prevalence rate ratios (PRRs). The 1-month prevalence of GPNS at baseline was much greater than that of LNSP (35.1% vs 5.6%), and it tended to be more troublesome and disabling. Unlike LNSP, the prevalence of GPNS increased with age. Moreover, it showed significantly stronger associations with somatising tendency (PRR 1.6 vs 1.3) and poor mental health (PRR 1.3 vs 1.1); greater variation between the occupational groups studied (prevalence ranging from 0% to 67.6%) that correlated poorly with the variation in LNSP; and was more persistent at follow-up (72.1% vs 61.7%). Our findings highlight important epidemiological distinctions between subcategories of neck/shoulder pain. In future epidemiological research that bases case definitions on symptoms, it would be useful to distinguish pain that is localised to the neck or shoulder from more generalised pain that happens to involve the neck/shoulder region.

Patterns of multisite pain and associations with risk factors.

To explore definitions for multisite pain, and compare associations with risk factors for different patterns of musculoskeletal pain, we analysed cross-sectional data from the Cultural and Psychosocial Influences on Disability (CUPID) study. The study sample comprised 12,410 adults aged 20-59 years from 47 occupational groups in 18 countries. A standardised questionnaire was used to collect information about pain in the past month at each of 10 anatomical sites, and about potential risk factors. Associations with pain outcomes were assessed by Poisson regression, and characterised by prevalence rate ratios (PRRs). Extensive pain, affecting 6-10 anatomical sites, was reported much more frequently than would be expected if the occurrence of pain at each site were independent (674 participants vs 41.9 expected). In comparison with pain involving only 1-3 sites, it showed much stronger associations (relative to no pain) with risk factors such as female sex (PRR 1.6 vs 1.1), older age (PRR 2.6 vs 1.1), somatising tendency (PRR 4.6 vs 1.3), and exposure to multiple physically stressing occupational activities (PRR 5.0 vs 1.4). After adjustment for number of sites with pain, these risk factors showed no additional association with a distribution of pain that was widespread according to the frequently used American College of Rheumatology criteria. Our analysis supports the classification of pain at multiple anatomical sites simply by the number of sites affected, and suggests that extensive pain differs importantly in its associations with risk factors from pain that is limited to only a small number of anatomical sites.

Disabling musculoskeletal pain in working populations: is it the job, the person, or the culture?

To compare the prevalence of disabling low back pain (DLBP) and disabling wrist/hand pain (DWHP) among groups of workers carrying out similar physical activities in different cultural environments, and to explore explanations for observed differences, we conducted a cross-sectional survey in 18 countries. Standardised questionnaires were used to ascertain pain that interfered with everyday activities and exposure to possible risk factors in 12,426 participants from 47 occupational groups (mostly nurses and office workers). Associations with risk factors were assessed by Poisson regression. The 1-month prevalence of DLBP in nurses varied from 9.6% to 42.6%, and that of DWHP in office workers from 2.2% to 31.6%. Rates of disabling pain at the 2 anatomical sites covaried (r = 0.76), but DLBP tended to be relatively more common in nurses and DWHP in office workers. Established risk factors such as occupational physical activities, psychosocial aspects of work, and tendency to somatise were confirmed, and associations were found also with adverse health beliefs and group awareness of people outside work with musculoskeletal pain. However, after allowance for these risk factors, an up-to 8-fold difference in prevalence remained. Systems of compensation for work-related illness and financial support for health-related incapacity for work appeared to have little influence on the occurrence of symptoms. Our findings indicate large international variation in the prevalence of disabling forearm and back pain among occupational groups carrying out similar tasks, which is only partially explained by the personal and socioeconomic risk factors that were analysed.

The CUPID (Cultural and Psychosocial Influences on Disability) study: methods of data collection and characteristics of study sample.

BACKGROUND: The CUPID (Cultural and Psychosocial Influences on Disability) study was established to explore the hypothesis that common musculoskeletal disorders (MSDs) and associated disability are importantly influenced by culturally determined health beliefs and expectations. This paper describes the methods of data collection and various characteristics of the study sample. METHODS/PRINCIPAL FINDINGS: A standardised questionnaire covering musculoskeletal symptoms, disability and potential risk factors, was used to collect information from 47 samples of nurses, office workers, and other (mostly manual) workers in 18 countries from six continents. In addition, local investigators provided data on economic aspects of employment for each occupational group. Participation exceeded 80% in 33 of the 47 occupational groups, and after pre-specified exclusions, analysis was based on 12,426 subjects (92 to 1018 per occupational group). As expected, there was high usage of computer keyboards by office workers, while nurses had the highest prevalence of heavy manual lifting in all but one country. There was substantial heterogeneity between occupational groups in economic and psychosocial aspects of work; three- to five-fold variation in awareness of someone outside work with musculoskeletal pain; and more than ten-fold variation in the prevalence of adverse health beliefs about back and arm pain, and in awareness of terms such as "repetitive strain injury" (RSI). CONCLUSIONS/SIGNIFICANCE: The large differences in psychosocial risk factors (including knowledge and beliefs about MSDs) between occupational groups should allow the study hypothesis to be addressed effectively.

Decreases in circulating CD4+CD25hiFOXP3+ cells and increases in intragraft FOXP3+ cells accompany allograft rejection in pediatric liver allograft recipients.

We examined CD4(+)CD25(hi)FOXP3(+) cells Treg in children following liver transplantation and determined the relationship between Treg cell levels in the blood and in the graft. Peripheral blood was obtained from pediatric liver transplant patients at sequential time points: pre-transplant, one month, 3-4 months, 6-7 months, and 11-12 months post-transplant. PBMC were isolated, labeled for CD4, CD25 and FOXP3 expression and analyzed by flow cytometry for CD4(+)CD25(hi)FOXP3(+) cells. Sorted CD4(+)CD25(hi) cells were assessed for functional activity. Pretransplant blood levels of CD4(+)CD25(hi)FOXP3(+) Treg cells were not significantly different from post-transplant blood levels of CD4(+)CD25(hi)FOXP3(+) Treg cells. However, the blood levels of CD4(+)CD25(hi)FOXP3(+) Treg cells were significantly decreased during acute rejection compared with levels when graft function was stable. Immunohistochemistry revealed that FOXP3(+) cells were increased in the portal region of livers with histopathologic evidence of acute graft rejection compared with livers without evidence of rejection and were localized primarily within the inflammatory infiltrate. These data indicate that Treg cells are found at the site of allograft rejection and may play a role in regulation of alloreactivity. Moreover, monitoring peripheral CD4(+)CD25(hi)FOXP3(+) Treg cell levels may be useful in improving the post-transplant management of pediatric liver allograft recipients.

Long-term outcome following total hip arthroplasty: a controlled longitudinal study.

OBJECTIVE: To assess long-term outcome and predictors of prognosis following total hip arthroplasty (THA) for osteoarthritis (OA). METHODS: We studied 282 patients from 2 English health districts approximately 8 years after THA, along with 295 controls selected from the general population. Baseline data were collected by interview and examination, on sex, age, comorbidity, body mass index (BMI), and Short Form 36 (SF-36) functional status, and preoperative radiographic severity of OA was graded. Functional status was reassessed at followup by postal questionnaire. Predictors of change in physical functioning were analyzed by linear regression. RESULTS: Over followup, cases who had THA reported a median improvement of 10 points in SF-36 score for physical functioning, whereas in controls there was a median deterioration of 10 points (P < 0.0001). Mental health improved by a median of 12 points in both cases and controls. Change in physical functioning was significantly worse in women and at older ages among both cases and controls. In cases, Croft grade 5 OA was associated with a physical functioning score improvement 19.4 points (95% confidence interval 7.7, 31.2) greater than the improvement in grades 0-3, but BMI was unrelated to change in physical functioning. CONCLUSION: Improvements in physical functioning following THA for OA are sustained in the long term and are more frequent in patients with more severe radiographic features preoperatively. We found no indication that patients who are overweight benefit less from THA, but further evidence is needed on the prognostic influence of more severe obesity.

Perceiving clinical evidence.

BACKGROUND: This paper demystifies clinical perception by explaining its mechanisms, using insights from neuroscience and evolutionary biology. Clinical diagnosis begins with rapid recognition using our imaging, perceptual (but non-verbal) brain, followed by guided search using our slower, verbal, reasoning brain. Experiential cognition can be (more or less) achieved by integrating these two ways of knowing. Perceptual expertise requires alertness and persistence to ensure clinical accuracy. Each clinician, as a self-aware participant-observer (SAPO) keeping track of what they're thinking 'as it happens', can study their perceptual accuracy, pattern matching, interpretation, motivation and judgement.

Recovery of genomic DNA from archived PCR product mixes for subsequent multiplex amplification and typing of additional loci: forensic significance for older unsolved criminal cases.

A method for genomic DNA recovery from different types of PCR product mixes suitable for multiplex amplification and typing using the Profiler Plus STR typing system has been investigated. The application of this method is of significance in cases where the original DNA samples have been exhausted due to repeated typing analyses in an effort to maximize their evidentiary value. Such cases typically involve samples analyzed using the available DNA typing systems of the time which gave a markedly lower power of discrimination, either alone or in combination, compared to that of modern multiplex STR typing systems. It was found that an effective method for recovering genomic DNA from HLA-DQA1 +PM and CTT triplex amplification mixes, suitable for reproducible achievement of the complete Profiler Plus profile, involved the use of Amicon Microcon-100 microconcentrators. Interestingly, this method was not required to achieve the complete nine STR profile using D1S80 amplification mixes.

Who's my doctor today?

Clinical practice is not always user-friendly. Specialisation fragments patient care across different investigations and modes of management. Increasing hospital throughput, especially by day surgery, diminishes the time available for students and other health professionals in the team to interact with the patient and verify the appropriateness of the care plan. Patients are at a serious disadvantage in ensuring that their concerns are understood, and in negotiation of which management plan would optimise the outcomes they seek.