Individual preferences for physical exercise as secondary prevention for non-specific low back pain: A discrete choice experiment

Background

Exercise is effective in improving non-specific low back pain (LBP). Certain components of physical exercise, such as the type, intensity and frequency of exercise, are likely to influence participation among working adults with non-specific LBP, but the value and relative importance of these components remain unknown. The study’s aim was to examine such specific components and their influence on individual preferences for exercise for secondary prevention of non-specific LBP among working adults.

Methods

In a discrete choice experiment, working individuals with non-specific LBP answered a web-based questionnaire. Each respondent was given ten pairs of hypothetical exercise programs and asked to choose one option from each pair. The choices comprised six attributes of exercise (i.e., type of training, design, intensity, frequency, proximity and incentives), each with either three or four levels. A conditional logit regression that reflected the random utility model was used to analyze the responses.

Results

The final study population consisted of 112 participants. The participants’ preferred exercise option was aerobic (i.e., cardiovascular) rather than strength training, group exercise with trainer supervision, rather than individual or unsupervised exercise. They also preferred high intensity exercise performed at least once or twice per week. The most popular types of incentive were exercise during working hours and a wellness allowance rather than coupons for sports goods. The results show that the relative value of some attribute levels differed between young adults (age ≤ 44 years) and older adults (age ≥ 45 years) in terms of the level of trainer supervision required, exercise intensity, travel time to exercise location and financial incentives. For active study participants, exercise frequency (i.e., twice per week, 1.15; CI: 0.25; 2.06) influenced choice of exercise. For individuals with more than one child, travel time (i.e., 20 minutes, -0.55; CI: 0.65; 3.26) was also an influential attribute for choice of exercise, showing that people with children at home preferred to exercise close to home.

Conclusions

This study adds to our knowledge about what types of exercise working adults with back pain are most likely to participate in. The exercise should be a cardiovascular type of training carried out in a group with trainer supervision. It should also be of high intensity and preferably performed twice per week during working hours. Coupons for sports goods do not appear to motivate physical activity among workers with LBP. The findings of the study could have a substantial impact on the planning and development of exercise provision and promotion strategies to improve non-specific LBP. Providers and employers may be able to improve participation in exercise programs for adults with non-specific LBP by focusing on the exercise components which are the most attractive. This in turn would improve satisfaction and adherence to exercise interventions aimed at preventing recurrent non-specific LBP.

Estimating the Effect and Economic Impact of Absenteeism, Presenteeism, and Work Environment-Related Problems on Reductions in Productivity from a Managerial Perspective

OBJECTIVES

The aim of this study was to propose wage multipliers that can be used to estimate the costs of productivity loss for employers in economic evaluations, using detailed information from managers.

METHODS

Data were collected in a survey panel of 758 managers from different sectors of the labor market. Based on assumed scenarios of a period of absenteeism due to sickness, presenteeism and work environment-related problem episodes, and specified job characteristics (i.e., explanatory variables), managers assessed their impact on group productivity and cost (i.e., the dependent variable). In an ordered probit model, the extent of productivity loss resulting from job characteristics is predicted. The predicted values are used to derive wage multipliers based on the cost of productivity estimates provided by the managers.

RESULTS

The results indicate that job characteristics (i.e., degree of time sensitivity of output, teamwork, or difficulty in replacing a worker) are linked to productivity loss as a result of health-related and work environment-related problems. The impact of impaired performance on productivity differs among various occupations. The mean wage multiplier is 1.97 for absenteeism, 1.70 for acute presenteeism, 1.54 for chronic presenteeism, and 1.72 for problems related to the work environment. This implies that the costs of health-related and work environment-related problems to organizations can exceed the worker's wage.

CONCLUSIONS

The use of wage multipliers is recommended for calculating the cost of health-related and work environment-related productivity loss to properly account for actual costs.

Valuing Individuals' Preferences and Health Choices of Physical Exercise

The efficacy of physical exercise for the prevention and treatment of non-specific low back pain (LBP) is well documented, but little is known about how individuals value specific components of physical exercise, such as the type and design or the intensity and frequency of exercise. Other factors that influence individual differences in health choices and adherence are associated with individuals’ attitudes toward and likelihood of performing recommended exercise regimens. Current evidence shows that efficacy is similar among exercise interventions, but their features vary widely. Thus it may be difficult for clinicians to discriminate between available options in clinical practice. Considering the many challenges in determining the form of exercise best suited to the individual patient, this commentary discusses some of the practical methods that could be used to elicit individual preference for recommended health care interventions. Such methods have the advantage of providing more information for health care decision making, particularly with regard to exercise interventions for LBP. This commentary also advocates for the use of patient preference in health care decisions.

Validity and test-retest reliability of an at-work production loss instrument

BACKGROUND

Besides causing ill health, a poor work environment may contribute to production loss. Production loss assessment instruments emphasize health-related consequences but there is no instrument to measure reduced work performance related to the work environment.

AIMS

To examine convergent validity and test-retest reliability of health-related production loss (HRPL) and work environment-related production loss (WRPL) against a valid comparable instrument, the Health and Work Performance Questionnaire (HPQ).

METHODS

Cross-sectional study of employees, not on sick leave, who were asked to self-rate their work performance and production losses. Using the Pearson correlation and Bland and Altman's Test of Agreement, convergent validity was examined. Subgroup analyses were performed for employees recording problem-specific reduced work performance. Consistency of pairs of HRPL and WRPL for samples responding to both assessments was expressed using Intraclass Correlation Coefficient (ICC) and tests of repeatability.

RESULTS

A total of 88 employees participated and 44 responded to both assessments. Test of agreement between measurements estimates a mean difference of 0.34 for HRPL and -0.03 for WRPL compared with work performance. This indicates that the production loss questions are valid and moderately associated with work performance for the total sample and subgroups. ICC for paired HRPL assessments was 0.90 and 0.91 for WRPL, i.e. the test-retest reliability was good and suggests stability in the instrument.

CONCLUSIONS

HRPL and WRPL can be used to measure production loss due to health-related and work environment-related problems. These results may have implications for advancing methods of assessing production loss, which represents an important cost to employers.

Socioeconomic-related inequalities in child malnutrition: evidence from the Ghana multiple indicator cluster survey

BACKGROUND

Malnutrition is a prevalent public health concern in Ghana. While studies have identified factors that influence child malnutrition and related inequalities in Ghana, very little efforts have been made to decompose these inequalities across various household characteristics. This study examined the influence of socioeconomic factors on inequality in child malnutrition using a decomposition approach.

METHODS

The study employed cross section data from the 2011 Multiple Indicator Cluster Survey (MICS). Analysis was done at three levels: First, concentration curves were constructed to explore the nature of inequality in child malnutrition. Secondly, concentration indices were computed to quantify the magnitude of inequality. Thirdly, decomposition analysis was conducted to determine the role of mother's education and health insurance coverage in inequality of child malnutrition.

RESULTS

The concentration curves showed that there exists a pro-poor inequality in child malnutrition measured by stunting and wasting. The concentration indices of these measures indicated that the magnitude of inequality was higher and significant at 1 % for weight-for-age (WAZ) (-0.1641), relative to height-for-age (HAZ) (-0.1613). The decomposition analyses show that whilst mother's education contributed about 13 and 11 % to inequality in HAZ, it contributed about 18.9 and 11.8 % to inequality in WAZ for primary and secondary or above education attainments, respectively. Finally, health insurance contributed about 1.91 and 1.03 % to inequality in HAZ and WAZ, respectively.

CONCLUSION

The results suggest that there is the need to encourage critical policies directed towards improving female literacy in the country. The existence of a functional health insurance system and increasing universal coverage are recommended to mitigate child malnutrition.

Validation of a measure of health-related production loss: construct validity and responsiveness - a cohort study

Background

The aim of this study is to evaluate the construct validity and responsiveness of a Swedish measure of health-related production loss as well as to investigate if there is a difference in the level of production loss within a population suffering from persistent back/neck pain and CMDs.

Methods

The sample was drawn from a study that assessed employees’ health and working capacity in 74 health care units before and after intervention. The study included 692 patients who reported working the previous six months at baseline measurement, and who were also asked to answer questions related to health-related production loss. Health-related measures were general health derived from Short Form-12, health-related quality of life derived from EQ-5D, and work ability derived from the Work Ability Index (WAI). Convergent validity and external responsiveness were assessed using Spearman’s Rank Correlation Coefficient and a linear regression model, respectively.

Results

The different measures of health showed a moderate-to-strong correlation with the measure of health-related production loss and fulfilled the criteria for construct validity. Changes in health and work ability led to significant changes in health-related production loss, which demonstrates external responsiveness. This result is valid for both the total population and for the two different subgroups that were evaluated.

Conclusions

The present study shows that this measure of health-related production loss is a valid measure for capturing production loss due to illness, and that work ability is more strongly correlated with health-related production loss than people’s general health is. The result shows an average of about 50 % reduced production due to illness, with back pain being the most costly.

LARP1 post-transcriptionally regulates mTOR and contributes to cancer progression

RNA-binding proteins (RBPs) bind to and post-transcriptionally regulate the stability of mRNAs. La-related protein 1 (LARP1) is a conserved RBP that interacts with poly-A-binding protein and is known to regulate 5'-terminal oligopyrimidine tract (TOP) mRNA translation. Here, we show that LARP1 is complexed to 3000 mRNAs enriched for cancer pathways. A prominent member of the LARP1 interactome is mTOR whose mRNA transcript is stabilized by LARP1. At a functional level, we show that LARP1 promotes cell migration, invasion, anchorage-independent growth and in vivo tumorigenesis. Furthermore, we show that LARP1 expression is elevated in epithelial cancers such as cervical and non-small cell lung cancers, where its expression correlates with disease progression and adverse prognosis, respectively. We therefore conclude that, through the post-transcriptional regulation of genes such as mTOR within cancer pathways, LARP1 contributes to cancer progression.

Cost-effectiveness of early interventions for non-specific low back pain: a randomized controlled study investigating medical yoga, exercise therapy and self-care advice

OBJECTIVE

To evaluate the cost-effectiveness of medical yoga as an early intervention compared with evidence-based exercise therapy and self-care advice for non-specific low back pain.

DESIGN

Randomized controlled trial with a cost-effectiveness analysis.

SUBJECTS

A total of 159 participants randomized into the medical yoga group (n = 52), the exercise therapy group (n = 52) and the self-care advice group (n = 55).

METHODS

The health outcome measure EQ-5D was applied to measure quality of life data combined with cost data collected from treatment groups from baseline to 12 months follow-up. Outcome measure was health-related quality of life (HRQL). Incremental cost per quality adjusted life year (QALY) was also calculated. Cost-effectiveness analysis was conducted primarily from the societal and employer perspectives.

RESULTS

Medical yoga is cost-effective compared with self-care advice if an employer considers the significant improvement in the HRQL of an employee with low back pain justifies the additional cost of treatment (i.e. in this study EUR 150). From a societal perspective, medical yoga is a cost-effective treatment compared with exercise therapy and self-care advice if an additional QALY is worth EUR 11,500. Sensitivity analysis suggests that medical yoga is more cost-effective than its alternatives.

CONCLUSION

Six weeks of uninterrupted medical yoga thera-py is a cost-effective early intervention for non-specific low back pain, when treatment recommendations are adhered to.

Elderly demand for family-based care and support: evidence from a social intervention strategy

This paper examines the influence of the national health insurance scheme on elderly demand for family-based care and support. It contributes to the growing concern on the rapid increase in the elderly population globally using micro-level social theory to examine the influence the health insurance has on elderly demand for family support. A qualitative case study approach is applied to construct a comprehensive and thick description of how the national health insurance scheme influences the elderly in their demand for family support. Through focused interviews and direct observation of six selected cases, in-depth information on primary carers, living arrangement and the interaction between the health insurance as structure and elders as agents are analyzed. The study highlights that the interaction between the elderly and the national health insurance scheme has produced a new stratum of relationship between the elderly and their primary carers. Consequently, this has created equilibrium between the elderly demand for support and support made available by their primary carers. As the demand of the elderly for support is declining, supply of support by family members for the elderly is also on the decline.

Maternal health-seeking behavior: the role of financing and organization of health services in Ghana

This paper examines how organization and financing of maternal health services influence health-seeking behavior in Bosomtwe district, Ghana. It contributes in furthering the discussions on maternal health-seeking behavior and health outcomes from a health system perspective in sub-Saharan Africa. From a health system standpoint, the paper first presents the resources, organization and financing of maternal health service in Ghana, and later uses case study examples to explain how Ghana's health system has shaped maternal health-seeking behavior of women in the district. The paper employs a qualitative case study technique to build a complex and holistic picture, and report detailed views of the women in their natural setting. A purposeful sampling technique is applied to select 16 women in the district for this study. Through face-to-face interviews and group discussions with the selected women, comprehensive and in-depth information on health- seeking behavior and health outcomes are elicited for the analysis. The study highlights that characteristics embedded in decentralization and provision of free maternal health care influence health-seeking behavior. Particularly, the use of antenatal care has increased after the delivery exemption policy in Ghana. Interestingly, the study also reveals certain social structures, which influence women's attitude towards their decisions and choices of health facilities.

Changes in [18F]Fluorothymidine Pharmacokinetics Following Capecitabine Treatment in Human Breast Cancer Detected by Positron Emission Tomography

Background: Pre-clinical models used by our group have demonstrated that thymidylate synthase (TS) inhibition leads to redistribution of the nucleoside transporter, ENT1, to the cell membrane and hence increases the tissue uptake of [18F]fluorothymidine (FLT).Methods: In this study we assessed, for the first time, the altered pharmacokinetics of FLT in patients following TS inhibition. We analyzed 10 lesions from 6 breast cancer patients by positron emission tomography (PET) before and after treatment with capecitabine.Results: Whereas drug treatment did not alter tumor delivery pharmacokinetic variables or blood flow, tumor FLT retention variables increased with drug treatment in all but one patient. The baseline average standardized uptake value (SUV) at 60 min, rate constant for the net irreversible transfer of radiotracer from plasma to tumor (Ki) and unit impulse response function (IRF) at 60 min were 11.11 x 10-5 m2/ml, 4.38 x 10-2 ml plasma/min/ml tissue and 4.93 x 10-2 /min, respectively. At 1 h after capecitabine, the SUV was 13.55 x 10-5 m2/ml (p=0.004), Ki 7.40 x 10-2 ml plasma/min/ml tissue (p=0.004) and IRF 7.40 x 10-2 /min (p= 0.002).Conclusion: FLT pharmacokinetics did not change in normal tissues suggesting that the effect was largely restricted to tumor (p=0.55). In summary, we have identified FLT-PET retention parameters that could be used in future early clinical studies to measure the pharmacodynamics of TS inhibitors, as well as for identifying patients who are unlikely to benefit from TS inhibition.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5003.

[11C]Choline-PET imaging of breast cancer

1110

Background: Molecular imaging techniques are increasingly being used in cancer diagnosis, staging, and assessment of response to treatment. This study sought to evaluate, for the first time, [11C]choline-PET in patients with breast cancer. The potential of [11C]choline-PET for differentiating tumours from normal tissue, correlation with molecular markers, determine its normal variability range, and finally the effect of trastuzumab on [11C]choline uptake in patients with breast cancer was investigated. Methods: 21 patients with newly diagnosed and recurrent breast cancer AJCC stage II-IV were enrolled in the study, all of whom had a baseline dynamic [11C]choline-PET scan with arterial sampling. 14 patients had 2 [11C]choline-PET scans to examine reproducibility, and 7 had a scan after trastuzumab. Analysis of [11C]choline uptake was measured using SUV, Ki (irreversible retention), and IRF@60min (retention using spectral analysis). Results: Breast tumour lesions were visualised by [11C]choline PET in all patients. The difference in tumour and non-tumour uptake were significant for SUV, Ki, and IRF@60 min (Wilcoxon p < 0.0001 for all parameters). [11C]choline uptake was reproducible in breast tumour lesions (r2 = 0.945 for SUV, 0.894 for Ki, and 0.799 for IRF60). The metabolism analysis of arterial plasma samples in 19 patients showed that [11C]choline decreased rapidly post-injection such that at 60 mins the mean radioactivity in arterial plasma due to choline was 15.15 ± 2.16%.Early responses to trastuzumab were determined to be significant in 5 lesions which corresponded with 3 clinical responses. Conclusions: [11C]choline-PET is a promising imaging modality in breast cancer, and could play an important role for determining response to novel treatment strategies in vivo.

No significant financial relationships to disclose.

Imaging of angiogenesis in metastatic breast cancer by positron emission tomography (PET) using [18F]AH11585, an [18F]- labeled alphaVbeta3 (αvβ3) peptide

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Background: In vivo imaging of avβ3 expression in tumors and tumor endothelial cells may be a useful biomarker of angiogenesis. [18F]AH11585 is a novel peptide containing an Arginine-Glycine-Aspartic Acid (RGD) motif that binds to avβ3 with high affinity designed for use in PET studies. Methods: 7 patients with metastatic breast cancer (aged 37–68 years) received intravenous injections of [18F]AH11585 and were scanned dynamically by PET over 61.5 mins. Radioactivity concentrations, derived from regions of interest placed on tumour and normal tissues, were analysed mathematically to determine the net irreversible uptake (Ki), fractional retention (FRT) and standardized uptake at 56.5min (SUV) of the radiotracer. Computed tomography (CT) was performed within 4 weeks of the scan. Results: Tumor lesions were clearly visible on PET images in 6/7 patients. In one patient with a palpable supraclavicular lymph node not visible on CT, we were unsure if a hyperintense region visible by PET was tumor. In total 18/19 tumor lesions were identified on both PET and corresponding CT images. Tumors in areas of low background were hyperintense (lung, bone, breast) whereas those in areas of high background were hypointense regions (liver). Tumors with central necrosis showed high uptake of [18F]AH11585 around the periphery only. Mathematical analysis demonstrated irreversible retention of [18F]AH11585 in tumors. [18F]AH11585-PET discriminated between non-liver lesions (n=10) and normal tissues: Ki (p=0.002), FRT (p=0.0039), SUV (p=0.002). Corresponding comparisons for liver lesions (n=8) were significant for FRT (p=0.0078) and SUV (p=0.0078) only. Conclusions: [18F]AH11585 PET is a promisng method for in vivo imaging of avβ3 integrin expression in metastatic breast cancer.

No significant financial relationships to disclose.

A feasibility study of [11C]choline for the molecular imaging of human breast cancer in vivo using positron emission tomography (PET)

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Background: [11C]Choline is a novel PET radiotracer. Preclinical studies suggest that it may be promising in breast cancer. [11C]Choline has been recently evaluated as a screening agent in prostate cancer, but no studies have yet investigated its potential in breast cancer. We report a pilot study evaluating the utility and reproducibility of [11C]Choline-PET in breast cancer. Methods: Dynamic imaging was performed on an ECAT962 HR+ PET scanner for 65 min after intravenous injection with 190–369 MBq [11C]choline. Patients with locally advanced and metastatic breast cancer were eligible. All histological subtypes were included (ductal, lobular, and inflammatory). Arterial blood samples were taken continuously for 10 min, with 8 discrete samples up to 60 min to measure [11C]choline and metabolites. Tissue uptake was determined by standardised uptake value at 60 min (SUV, dose and BSA corrected) and Ki (irreversible trapping) calculated using Patlak (corrected for [11C]choline metabolites in plasma) and modified Patlak analysis (corrected for plasma + tissue metabolites). Reproduciblilty scans were performed 2–17 days later in the absence of treatment. Results: Tumour [11C]choline uptake was observed in 10 out of 11 patients (12 out of 13 distinct lesions). There was a significant difference between tumour and normal tissue (breast/lung) in [11C]choline uptake for Ki (p<0.0001) and SUV (p<0.0001). Tissue uptake was of the order lung ≤ normal breast < tumour < liver ≤ spleen. [11C]choline was rapidly metabolised, at 60 min the mean ± S.E. plasma radioactivity due to [11C]choline was 16.4 ± 2.9%. [11C]Choline uptake was found to be reproducible for Ki (modified Patlak: r=0.93, p<0.0001, Patlak: r=0.85, p=0.002) and SUV (r=0.94, p<0.0001) - measured in 8 patients (median of 2 days after the 1st scan). Tumour Patlak Ki was 13.2% > Ki calculated using modified Patlak analysis. Conclusions: [11C]Choline-PET imaging of breast cancer is promising and warrants further evaluation. Tumour [11C]Choline uptake measured by Ki and SUV is reproducible. We plan to study the relationship between choline uptake measured by PET and immunoassays of tumour samples. Functional imaging could have a vital role to determine the efficacy of target-specific agents.

No significant financial relationships to disclose.