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

A systematic review and meta-analysis of the prevalence of chronic widespread pain in the general population.

Chronic widespread pain (CWP) is common and associated with poor general health. There has been no attempt to derive a robust prevalence estimate of CWP or assess how this is influenced by sociodemographic factors. This study therefore aimed to determine, through a systematic review and meta-analysis, the prevalence of CWP in the adult general population and explore variation in prevalence by age, sex, geographical location, and criteria used to define CWP. MEDLINE, Embase, CINAHL, and AMED were searched using a search strategy combining key words and related database-specific subject terms to identify relevant cohort or cross-sectional studies published since 1990. Included articles were assessed for risk of bias. Prevalence figures for CWP (American College of Rheumatology criteria) were stratified according to geographical location, age, and sex. Potential sources of variation were investigated using subgroup analyses and meta-regression. Twenty-five articles met the eligibility criteria. Estimates for CWP prevalence ranged from 0% to 24%, with most estimates between 10% and 15%. The random-effects pooled prevalence was 10.6% (95% confidence intervals: 8.6-12.9). When only studies at low risk of bias were considered pooled, prevalence increased to 11.8% (95% confidence intervals: 10.3-13.3), with reduced but still high heterogeneity. Prevalence was higher in women and in those aged more than 40 years. There was some limited evidence of geographic variation and cultural differences. One in 10 adults in the general population report chronic widespread pain with possible sociocultural variation. The possibility of cultural differences in pain reporting should be considered in future research and the clinical assessment of painful conditions

Exercise for lower limb osteoarthritis : systematic review incorporating trial sequential analysis and network meta-analysis

Objective: To determine whether there is sufficient evidence to conclude that exercise interventions are more effective than no exercise control and to compare the effectiveness of different exercise interventions in relieving pain and improving function in patients with lower limb osteoarthritis. Data sources: Nine electronic databases searched from inception to March 2012. Study selection: Randomised controlled trials comparing exercise interventions with each other or with no exercise control for adults with knee or hip osteoarthritis. Data extraction: Two reviewers evaluated eligibility and methodological quality. Main outcomes extracted were pain intensity and limitation of function. Trial sequential analysis was used to investigate reliability and conclusiveness of available evidence for exercise interventions. Bayesian network meta-analysis was used to combine both direct (within trial) and indirect (between trial) evidence on treatment effectiveness. Results: 60 trials (44 knee, two hip, 14 mixed) covering 12 exercise interventions and with 8218 patients met inclusion criteria. Sequential analysis showed that as of 2002 sufficient evidence had been accrued to show significant benefit of exercise interventions over no exercise control. For pain relief, strengthening, flexibility plus strengthening, flexibility plus strengthening plus aerobic, aquatic strengthening, and aquatic strengthening plus flexibility, exercises were significantly more effective than no exercise control. A combined intervention of strengthening, flexibility, and aerobic exercise was also significantly more effective than no exercise control for improving limitation in function (standardised mean difference −0.63, 95% credible interval −1.16 to −0.10). Conclusions: As of 2002 sufficient evidence had accumulated to show significant benefit of exercise over no exercise in patients with osteoarthritis, and further trials are unlikely to overturn this result. An approach combining exercises to increase strength, flexibility, and aerobic capacity is likely to be most effective in the management of lower limb osteoarthritis. The evidence is largely from trials in patients with knee osteoarthritis

Carbon Nanotube-based Sensor and Method for Continually Sensing Changes in a Structure

A sensor has a plurality of carbon nanotube (CNT)-based conductors operatively positioned on a substrate. The conductors are arranged side-by-side, such as in a substantially parallel relationship to one another. At least one pair of spaced-apart electrodes is coupled to opposing ends of the conductors. A portion of each of the conductors spanning between each pair of electrodes comprises a plurality of carbon nanotubes arranged end-to-end and substantially aligned along an axis. Because a direct correlation exists between resistance of a carbon nanotube and carbon nanotube strain, changes experienced by the portion of the structure to which the sensor is coupled induce a change in electrical properties of the conductors

Water-Based Pressure-Sensitive Paints

Water-based pressure-sensitive paints (PSPs) have been invented as alternatives to conventional organic-solvent-based pressure-sensitive paints, which are used primarily for indicating distributions of air pressure on wind-tunnel models. Typically, PSPs are sprayed onto aerodynamic models after they have been mounted in wind tunnels. When conventional organic-solvent-based PSPs are used, this practice creates a problem of removing toxic fumes from inside the wind tunnels. The use of water-based PSPs eliminates this problem. The waterbased PSPs offer high performance as pressure indicators, plus all the advantages of common water-based paints (low toxicity, low concentrations of volatile organic compounds, and easy cleanup by use of water)

Controlled Deposition and Alignment of Carbon Nanotubes

A carbon nanotube (CNT) attraction material is deposited on a substrate in the gap region between two electrodes on the substrate. An electric potential is applied to the two electrodes. The CNT attraction material is wetted with a solution defined by a carrier liquid having carbon nanotubes (CNTs) suspended therein. A portion of the CNTs align with the electric field and adhere to the CNT attraction material. The carrier liquid and any CNTs not adhered to the CNT attraction material are then removed

Carbon Nanotube Based Light Sensor

A light sensor substrate comprises a base made from a semi-conductive material and topped with a layer of an electrically non-conductive material. A first electrode and a plurality of carbon nanotube (CNT)-based conductors are positioned on the layer of electrically non-conductive material with the CNT-based conductors being distributed in a spaced apart fashion about a periphery of the first electrode. Each CNT-based conductor is coupled on one end thereof to the first electrode and extends away from the first electrode to terminate at a second free end. A second or gate electrode is positioned on the non-conductive material layer and is spaced apart from the second free end of each CNT-based conductor. Coupled to the first and second electrode is a device for detecting electron transfer along the CNT-based conductors resulting from light impinging on the CNT-based conductors

Controlled Deposition and Alignment of Carbon Nanotubes

A carbon nanotube (CNT) attraction material is deposited on a substrate in the gap region between two electrodes on the . substrate. An electric potential is applied to the two electrodes. The CNT attraction material is wetted with a solution defined by a carver liquid having carbon nanotubes (CNTs) suspended therein. A portion of the CNTs align with the electric field and adhere to The CNT attraction material. The carrier liquid and any CNTs not adhered to the CNT attraction material are then removed

Examining whether the information-motivation-behavioral skills model predicts medication adherence for patients with a rare disease.

The information-motivation-behavioral skills (IMB) model has been used to explain and promote medication adherence among patients with diabetes and HIV. The objective of this study was to examine whether the IMB model predicted medication adherence among vasculitis patients. Adult vasculitis patients (n=228) completed online questionnaires at baseline and 3-month follow-up. Linear regressions were calculated to determine the direct effects of information and motivation on medication adherence (P<0.05). A mediation analysis using a bootstrapping approach was used to test whether behavioral skills significantly mediated the effect of information and motivation on medication adherence. Participants reported high levels of information (M=4.0; standard deviation [SD]=0.68), moderate levels of motivation (M=2.7; SD=1.00), and high levels of behavioral skills (M=4.1; SD=0.74). In the regression model, only behavioral skills (B=0.38; P<0.001) were significantly associated with medication adherence; however, mediation analysis revealed that behavioral skills significantly mediated the effects of information and motivation on medication adherence. The results support the IMB-hypothesized relationships between information, motivation, behavioral skills, and medication adherence in our sample. Findings suggest that providers should work with vasculitis patients to increase their medication-related skills to improve medication adherence

Chronic Pain and Mortality: A Systematic Review

Abstract 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