Structural equation modelling of the moderation effect of health locus of control on the pain-depression pathway

Background and aims Low back pain (LBP) is common, and is a major health concern. Psychological consequences of LBP, such as depression, are significant barriers to recovery, but mechanisms for the development of depression are less well understood. One potential mechanism is the individuals’ Health Locus of Control (HLOC), i.e. perception of the level of control an individual has over their health. The aim of this study is to investigate the moderation effect of HLOC on the pain-depression pathway. Methods Cross sectional study of participants (n = 637) from two cohorts of primary care LBP patients. Two Structural Equation Model analysis groups were created (low perceived control, and high perceived control), based on the HLOC Internality Scale. The path model consisted of pain intensity and disability as exogenous predictors, pain interference (endogenous mediator), bothersomeness (endogenous predictor) and depression (outcome). Critical ratio difference tests were applied to the coefficients using pairwise comparisons. Results Both models had an acceptable model fit. Critical ratio tests indicated a significant (p < 0.05) moderation effect, with stronger pathway coefficients for depression for those who report low Internality (β 0.48), compared to those with high Internality (β 0.26). Conclusions HLOC Internality significantly moderates the pain-depression pathway in those with back pain, meaning that those who have a low perception of control report greater levels of depression. This may signify a potential factor that may predict depression among people with pain, and could potentially be a target for intervention

The pain, depression, disability pathway in those with low back pain: a moderation analysis of health locus of control

Low back pain (LBP) is common, impacts on the individual and society, and is a major health concern. Psychological consequences of LBP, such as depression, are significant barriers to recovery, but mechanisms for the development of depression are less well understood. One potential mechanism is the individual’s health locus of control (HLoC), that is, perception of the level of control an individual has over their health. The objective of this study is to investigate the moderation effect of HLoC on the pain–depression–disability pathway in those with LBP. The design is a nested cross-sectional analysis of two existing cohorts of patients (n=637) who had previously consulted their primary care physician about LBP. Measures were taken of HLoC, pain intensity and interference, depression, disability, and bothersomeness. Structural Equation Modeling analysis was applied to two path models that examined the pain to depression to disability pathway moderated by the HLoC constructs of Internality and Externality, respectively. Critical ratio (CR) difference tests were applied to the coefficients using pairwise comparisons. The results show that both models had an acceptable model fit and pathways were significant. CR tests indicated a significant moderation effect, with stronger pathway coefficients for depression for those who report low Internality (β 0.48), compared to those with high Internality (β 0.28). No moderation effects were found within the Externality model. HLoC Internality significantly moderates the pain–depression pathway in those with LBP, meaning that those who have a low perception of control report greater levels of depression. HLoC may signify depression among people with LBP, and could potentially be a target for intervention

Are sleep problems a risk factor for the onset of musculoskeletal pain in children and adolescents? A systematic review

Study Objectives: Musculoskeletal pain is a major burden on the society. Adults with sleep problems are at higher risk of musculoskeletal pain onset, but there is no evidence for this relationship in children and adolescents. This study aimed to systematically review prospective studies on the risk of musculoskeletal pain onset in children and adolescents with sleep problems. Methods: Five databases (MEDLINE, PsycINFO, AMED, EMBASE, and HMIC) were systematically searched to identify prospective studies that investigated if children and adolescents (aged 6–19 years) with sleep problems are at higher risk of musculoskeletal pain onset. Included studies were assessed for study quality and a best evidence synthesis was carried out on extracted data. Results: Thirteen prospective studies were identified. Overall, evidence indicates that sleep problems (quality, quantity, and day time tiredness) are not risk factors for musculoskeletal pain onset. Further analysis on specific body regions shows strong evidence that sleep problems are a risk factor for neck pain onset (only in girls) and that sleep problems are not a risk factor for the onset of widespread pain. Conclusions: Overall, sleep problems are not a risk factor for musculoskeletal pain onset in children and adolescents. Increased risk was found for some specific body regions and subgroups, but the evidence base was less strong and generally inconsistent. This review found a lack of quality in research methodology compared to research in adults, and further research with improved methodology is required

Validity of the Visual Trajectories Questionnaire for Pain (VTQ-Pain)

Researchers have identified trajectories of pain derived using statistical techniques on longitudinal data. These trajectories have potential to be of use clinically but the repeated data collection required is currently impractical for such situations. Our aim was to investigate the validity of a self-report (Visual Trajectories Questionnaire-Pain) for pain. Analysis included participants from 2 prospective cohorts of people seeking primary health care for back pain (n = 622). A question was developed asking people to classify their pain experience into one of a number of trajectories using visual and word descriptions. Overall 98% of participants completed the question; criterion validity was established by comparing self-report trajectories and trajectories derived using longitudinal latent class analysis, and construct validity was established by comparing responses to the questionnaire against an existing model of back pain stages. As expected variables such as pain intensity and widespreadness, other symptoms, and psychological distress showed an increasing trend of severity across trajectory categories in line with the hypothesized model. In conclusion, the self-report single-item Visual Trajectories Questionnaire-Pain is acceptable to patients and supported by evidence of face, criterion, and construct validity. Further research is needed to investigate the clinical usefulness of the question

Neuropathic pain in low back-related leg pain patients: What is the evidence of prevalence, characteristics, and prognosis in primary care? A systematic review of the literature.

This systematic review synthesizes literature describing prevalence, characteristics and prognosis of low back-related leg pain (LBLP) patients with neuropathic pain in primary care and/or similar settings. Inclusion and exclusion criteria were developed and used by independent reviewers to screen citations for eligibility. The initial search yielded 24,948 citations; after screening 12 studies were included. Neuropathic pain was identified by case ascertainment tools (n=5), by clinical history with examination (n=4), and by LBLP samples assumed neuropathic (n=3). Neuropathic pain prevalence varied from 19% to 80%. There was consistent evidence for higher back-related disability (n=3), poorer health-related quality of life (n=2) and some evidence for more severe depression (n=2), anxiety (n=3) and pain intensity (n=4) in patients with neuropathic pain. Results were less consistent when cases were identified through clinical history plus examination than those identified using case ascertainment tools. Prognosis (n=1) of LBLP patients with neuropathic pain was worse compared to those without, in all outcomes (leg pain intensity, leg and back-related disability, self-reported general health) except back pain intensity. No studies described prognostic factors. This systematic review highlights the evidence gap in neuropathic pain in LBLP in primary care, especially with respect to prognosis. PERSPECTIVE: Patients with low back-related leg pain may have neuropathic pain. This systematic review emphasises the paucity of evidence describing the characteristics and prognosis of neuropathic pain in this patient population. Future research investigating prognosis of these patients with neuropathic pain is likely to contribute to better understanding and management

Is Spending Money on Others Good for Your Heart?

Objective: Does spending money on others (prosocial spending) improve the cardiovascular health of community-dwelling older adults diagnosed with high blood pressure? Method: In Study 1, 186 older adults diagnosed with high blood pressure participating in the Midlife in the U.S. Study (MIDUS) were examined. In Study 2, 73 older adults diagnosed with high blood pressure were assigned to spend money on others or to spend money on themselves. Results: In Study 1, the more money people spent on others, the lower their blood pressure was 2 years later. In Study 2, participants who were assigned to spend money on others for 3 consecutive weeks subsequently exhibited lower systolic and diastolic blood pressure compared to participants assigned to spend money on themselves. The magnitude of these effects was comparable to the effects of interventions such as antihypertensive medication or exercise. Conclusions: Together, these findings suggest that spending money on others shapes cardiovascular health, thereby providing a pathway by which prosocial behavior improves physical health among at-risk older adults

Comprehensive Systematic Review of long-term opioids in women with chronic non cancer pain and associated reproductive dysfunction (hypothalmic-pituitary-gonadal axis disruption)

A comprehensive systematic literature review of reproductive side effects in women aged 18 to 55 years treated with opioids for 1 month or longer for chronic noncancer pain. A search of 7 databases including EMBASE and Medline was undertaken (October 2014 and a limited rerun April 2016). The search contained key words for opioids (generic and specific drug names) and side effects (generic and specific reproductive). Titles were screened using predefined criteria by a single reviewer and abstracts and full texts by 2 independent reviewers. A total of 10,684 articles were identified and 12 full texts (cohort [n 5 1], case–control [n 5 4], crosssectional [n 5 4], case series [n 5 1], and case report [n 5 2] with a maximum of 41 cases in 1 article) were included covering 3 different modes of administration: oral (n 5 6), intrathecal (n 5 5), and transdermal (n 5 1). Amenorrhoea occurred in 23% to 71% of those receiving oral or intrathecal opioids. Decreased libido was seen in 61% to 100%. Of the 10 studies that undertook hormonal assays, only 2 studies showed a statistically significant decrease in hormone levels. This review supports the view that there is a potential relationship between the use of long-term opioids in women and reproductive side effects. The evidence is however weak and the mode of administration, duration, type, and dose of opioid might influence associations. Although hormone levels were statistically significant in only 2 studies, women exhibited clinically important symptoms (decreased libido and altered menstrual cycle). Further investigation is required with larger cohorts and analysis of different delivery methods