The Association Between Obesity and Low Back Pain and Disability Is Affected by Mood Disorders: A Population-Based, Cross-Sectional Study of Men

Bone mineral density is not associated with incident high-intensity back pain: a 10-year cohort study in men

Although patients believe that osteoporosis is a painful condition, health professionals assume it is painless unless a fracture occurs. The association between BMD and back pain has not been examined longitudinally in community-based adults in an unbiased population using gold-standard measures. This study aimed to examine the association between BMD and incident high-intensity back pain and/or high disability over 10 years in Australian men without high-intensity symptoms at baseline. Men with no high-intensity back pain and/or high disability attending the Geelong Osteoporosis Study at the 5-year visit (occurring between 2006-2010) (considered the baseline for the current study) were followed for 10 years (reassessed between 2016-2021). Back pain and disability were assessed using the Graded Chronic Pain Scale at both time points. At baseline, DXA was used to measure lumbar spine and total hip BMD and spinal artefacts. The relationships between BMD and incident high-intensity pain and/or high disability at follow-up were examined using binary logistic regression, adjusted for age, body mass index, depression, education, smoking, mobility, and spinal artefacts. A total of 679 participants had no to low-intensity pain and/or no to low disability at baseline. A total of 441 attended follow-up, providing back pain and disability data. Thirty-seven men developed high-intensity pain and/or high disability. No association of BMD at any site was seen with incident high-intensity pain and/or high disability. BMD was not associated with incident high-intensity pain or disability in community-based men. These data provide evidence to dispel the erroneous community-held belief that low BMD is related to back pain and disability.

Management and Nursing Approaches to Low Back Pain: Investigating the Causal Association with Lifestyle-Related Risk Factors

BACKGROUND

Notwithstanding a plethora of observational studies, the causal implications of obesity, encompassing both body mass index (BMI) and waist circumference (WC), as well as type 2 diabetes (T2D), and lifestyle factors, in relation to the vulnerability to low back pain (LBP), remain enigmatic.

AIMS

This study was designed to investigate the related causal associations DESIGN: A two-sample Mendelian randomization (MR) analysis.

SETTINGS

By utilizing genetic variants associated with pertinent factors gleaned from genome-wide association studies (GWASs), We extracted independent genetic variants about exposures such as BMI, WC, T2D, smoking, alcohol consumption, and coffee intake from published GWASs, ensuring their genome-wide significance.

PARTICIPANTS/SUBJECTS

The GWASs were selected from the most up-to-date and largest publicly accessible databases.

METHODS

The summary data concerning LBP emanated from a GWAS of European cases and controls, which was based on the esteemed MRC-IEU (Medical Research Council Integrative Epidemiology Unit) consortium.

RESULTS

Heightened body mass index and waist circumference exhibited odds ratios of 1.003 (95% confidence interval [CI] = 1.002-1.004, p < 0.001) and 1.003 (95% CI = 1.002-1.004, p < 0.001) for LBP, respectively, per each standard deviation (SD) increase. As for smoking initiation and every SD increase in the frequency of alcohol intake, the odds ratios were 1.002 (95% CI = 1.001-1.003, p = 0.003) and 1.002 (95% CI = 1.000-1.003, p = 0.011), respectively, for LBP. Conversely, an increased log odds ratio for T2D, and prevalence of coffee intake, divulged no discernible causal effects on the risk of LBP.

CONCLUSION

This study provides suggestive evidence to support the causal involvement of obesity, smoking, and the frequency of alcohol intake in the development of LBP, which suggests that implementing measures to mitigate these risk factors may aid in preventing LBP.

Causations between obesity, diabetes, lifestyle factors and the risk of low back pain

BACKGROUND

Despite numerous observational studies, the causal relationship between obesity-measured by body mass index (BMI) and waist circumference (WC)-as well as type 2 diabetes (T2D), lifestyle habits, and susceptibility to low back pain (LBP) remains obscure.

METHODS

This investigation employed two-sample Mendelian randomization (MR) analysis to explore causality, using genetic variants linked to relevant factors from genome-wide association studies (GWASs). Specifically, we selected independent genetic variants related to BMI, WC, T2D, smoking, alcohol consumption, and coffee intake from established GWASs, all of which demonstrated genome-wide significance. The comparative data for LBP were derived from a GWAS involving European subjects, under the auspices of the renowned MRC-IEU (Medical Research Council Integrative Epidemiology Unit) consortium.

RESULTS

Elevated BMI and WC were associated with odds ratios of 1.002 (95% confidence interval [CI] = 1.001-1.004, p < 0.001) and 1.003 (95% CI = 1.002-1.004, p < 0.001) for LBP per standard deviation (SD) increase, respectively. Regarding smoking initiation and coffee consumption, the odds ratios stood at 1.002 (95% CI = 1.001-1.004, p = 0.001) and 1.004 (95% CI = 1.001-1.008, p = 0.034) for LBP, respectively. However, an augmented log odds ratio for T2D and each SD rise in alcohol consumption frequency revealed no significant causal impact on LBP risk.

CONCLUSION

Our findings indicate a potential causal link between obesity, smoking, and coffee intake in the genesis of LBP, suggesting that mitigating these factors could contribute to LBP prevention.

Longitudinal associations of body mass index and abdominal circumference with back pain among community-dwelling adults: data from the Osteoarthritis Initiative

BACKGROUND CONTEXT

Back pain is the most common musculoskeletal problem in both developed and developing countries. The prevalence and burden of back pain increases with age, and the management of back pain becomes increasingly important in the context of global aging. There is increasing evidence that obesity is a modifiable risk factor for musculoskeletal pain in different locations. Understanding the role of obesity in back pain holds great potential for improving understanding of the mechanisms of back pain and for developing new preventive and therapeutic approaches.

PURPOSE

To evaluate the role of weight, body mass index (BMI) and abdominal circumference (AC) in risk of back pain over 96 months.

DESIGN

Prospective cohort study.

PATIENT SAMPLE

The sample was from 4,793 adults in the Osteoarthritis Initiative (OAI) database who had or were at increased risk for knee Osteoarthritis.

OUTCOME MEASURES

Outcome variables included the presence, severity, and frequency of back pain, using the past 30 days as the time frame.

METHODS

Longitudinal analysis of data from 4,793 participants enrolled in the Osteoarthritis Initiative, assessed every 12 or 24 months for weight, BMI (kg/m2), AC (cm), and presence, severity (none, mild, moderate, severe), and frequency (none, rarely, sometimes, often, always) of back pain. BMI and AC were decomposed into between-person and with-person components. Data analyses were performed using mixed-effects logistic (for presence of back pain) or ordered logistic regression (for severity and frequency of back pain) models.

RESULTS

Back pain was reported in 58% of participants at baseline; 70% of those without back pain had incident back pain over 96 months. Both between-person (average value across a participant's all measurements) and within-person (deviations from the participant's average) effects of weight and BMI increased risk of presence, severity, and frequency of back pain (Odds radios (OR) per kg/m2: 1.010-1.046, p<.05) in females but not males, with statistically significant weight*sex and BMI*sex interactions. Similar findings were observed for between-person effects of AC on back pain, and the within-person effect of AC was only associated with back pain severity (OR per cm: 1.009, 95% confidence interval 1.002-1.017, p=.019) in females.

CONCLUSIONS

Greater average weight and BMI and increases in them increased odds of presence, severity, and frequency of back pain over 96 months in middle aged and older women but not men. Only average AC increased odds of back pain over time, in women. These findings suggest that preventing obesity and slowing weight gain is important for the management of back pain.

Correspondence Analysis to Demonstrate the Relationship Between Musculoskeletal Pain and Body Mass Index

Background As obese people frequently experience persistent musculoskeletal pain (MSP), understanding the relationship between obesity and pain may help develop therapeutic and preventative approaches to treat discomfort from MSP. MSP can negatively impact such individuals' quality of life and their ability to perform daily tasks. Therefore, more thorough investigations are required to fully understand the connection between obesity and MSP. Aims To assess the relationship between musculoskeletal pain(MSP) and body mass index (BMI) among women in the age group of 25 to 65 years. Methods From July to December 2022, a cross-sectional study among women between the ages of 25 and 65 was carried out near the Rural Health Training Centre (RHTC) of a medical college in the Lucknow District of Uttar Pradesh, India. In total, 443 women took part in the study. BMI was computed, weight and height were recorded, and MSP at any site (i.e., neck, shoulders, upper back, upper arms, lower back, forearms, wrists, hip/buttocks, thighs, knees, lower legs, and ankles) was noted. The data were analyzed through correspondence analysis. Results Of the 443 women that participated in the study, 224 (50.6%) had MSP, and 9.3% and 28.2% were obese or overweight, respectively. Obese and overweight women were found to be at a higher risk of upper and lower back pain. Conclusion In our study, a significant relationship between MSP and BMI was confirmed and visualized by correspondence analysis.

Impact of body mass index on PROMIS outcomes following lumbar decompression

BACKGROUND

No studies have examined the impact of body mass index (BMI) on newer Patient-Reported Outcomes Measurement Information System (PROMIS) outcomes in patients undergoing lumbar decompression (LD).

METHODS

Patients undergoing LD with preoperative PROMIS measures were stratified into four cohorts: normal (18.5 ≤ BMI < 25 kg/m²), overweight (25 ≤ BMI < 30 kg/m²), obese I (30 ≤ BMI < 35 kg/m²), and obese II-III (BMI ≥ 35 kg/m²). Demographics, perioperative characteristics, and patient-reported outcomes (PROs) were obtained. PROs of PROMIS Physical Function (PROMIS-PF), PROMIS Anxiety (PROMIS-A), PROMIS Pain Interference (PROMIS-PI), PROMIS Sleep Disturbance (PROMIS-SD), Patient Health Questionnaire-9 (PHQ-9), Visual Analog Scale (VAS) Back Pain (VAS-BP), VAS Leg Pain (VAS-LP), and Oswestry Disability Index (ODI) were collected at preoperative and up to 2-year postoperative time points. Minimum clinically important difference (MCID) achievement was determined through comparison of previously established values. Comparison between cohorts were determined through inferential statistics.

RESULTS

A total of 473 patients were identified, with stratification of 125 patients in the normal cohort, 161 in the overweight cohort, 101 in the obese I cohort, and 87 in the obese II-III cohort. Mean postoperative follow-up time was 13.51 ± 8.72 months. Higher BMI patients had higher operative times, longer postoperative length of stay, and greater narcotic consumption (p ≤ 0.001, all). Patients with higher BMI (obese I, obese II-III) reported inferior preoperative PROMIS-PF, VAS-BP, and ODI scores (p ≤ 0.003, all). Postoperatively, obese I-III cohorts demonstrated inferior PROMIS-PF, PHQ-9, VAS-BP, and ODI scores at final follow-up (p ≤ 0.016, all). However, patients demonstrated similar postoperative changes and MCID achievement regardless of preoperative BMI.

CONCLUSION

Patients undergoing lumbar decompression demonstrated similar postoperative improvement in physical function, anxiety, pain interference, sleep disturbance, mental health, pain, and disability outcomes independent of preoperative BMI. However, obese patients reported worse physical function, mental health, back pain, and disability outcomes at final postoperative follow-up. Patients with greater BMI undergoing lumbar decompression demonstrate inferior postoperative clinical outcomes.

The role of spinal surgery in the treatment of low back pain

Low back pain (LBP) is common and a leading cause of disability and lost productivity worldwide. Acute LBP is frequently self-resolving, but recurrence is common, and a significant proportion of patients will develop chronic pain. This transition is perpetuated by anatomical, biological, psychological and social factors. Chronic LBP should be managed with a holistic biopsychosocial approach of generally non-surgical measures. Spinal surgery has a role in alleviating radicular pain and disability resulting from neural compression, or where back pain relates to cancer, infection, or gross instability. Spinal surgery for all other forms of back pain is unsupported by clinical data, and the broader evidence base for spinal surgery in the management of LBP is poor and suggests it is ineffective. Emerging areas of interest include selection of a minority of patients who may benefit from surgery based on spinal sagittal alignment and/or nuclear medicine scans, but an evidence base is absent. Spinal surgery for back pain has increased substantially over recent decades, and disproportionately among privately insured patients, thus the contribution of industry and third-party payers to this increase, and their involvement in published research, requires careful consideration.

Controversies in spine research: Organ culture versus in vivo models for studies of the intervertebral disc

Intervertebral disc degeneration is a common cause of low back pain, the leading cause of disability worldwide. Appropriate preclinical models for intervertebral disc research are essential to achieving a better understanding of underlying pathophysiology and for the development, evaluation, and translation of more effective treatments. To this end, in vivo animal and ex vivo organ culture models are both widely used by spine researchers; however, the relative strengths and weaknesses of these two approaches are a source of ongoing controversy. In this article, members from the Spine and Preclinical Models Sections of the Orthopedic Research Society, including experts in both basic and translational spine research, present contrasting arguments in support of in vivo animal models versus ex vivo organ culture models for studies of the disc, supported by a comprehensive review of the relevant literature. The objective is to provide a deeper understanding of the respective advantages and limitations of these approaches, and advance the field toward a consensus with respect to appropriate model selection and implementation. We conclude that complementary use of several model types and leveraging the unique advantages of each is likely to result in the highest impact research in most instances.

A biopsychosocial examination of chronic back pain, limitations on usual activities, and treatment in Brazil, 2019

Background

Chronic back pain is prevalent in Brazil, leading to enormous healthcare costs and social burdens. It also disproportionately affects low-income and less-healthy people.

Objectives

This study examines the associations of chronic back pain with biological, psychological, and social factors; how it limits usual activities; and how chronic back pain influences the use of treatment services.

Methods

Using Brazil’s National Health Survey (PNS-2019), multivariate logistic regressions were conducted to examine how biological, psychological, and social factors correlate with chronic back pain, limitations on usual activities, and pain treatment.

Results

PNS-2019 data showed that 23.4% (95% CI 22.8–24.0) of Brazilian adults aged over 20 reported back pain. A higher prevalence of chronic back pain was associated with biological factors (older age, being female, overweight or obese, current smoking, and having more chronic conditions), lower social conditions (low education, low per capita household income, non-married, and living in rural areas), and poor psychological health (more depressive symptoms). Chronic back pain is more likely to limit usual activities among those with low social conditions (lower education, lower income), poor physical and behavioral health (obese, current smokers, and those with a greater number of chronic conditions), and worse psychological health (more depressive symptoms). However, married people and those who do not consume alcohol were also more likely to report limited activities. Among those with back pain, 68% received at least one form of treatment. Those with intense limitations on their usual activities were 2.2 times as likely to report treatment. People with higher social conditions (higher income, college education, and private health insurance) were more likely to receive treatment.

Conclusion

The results show significant biological, psychological, and social disparities in the prevalence of chronic back pain in Brazil. The findings point to the need for tailored policies and prevention programs with attention to vulnerable groups. Even though Brazil has universal health care, those with better socioeconomic conditions are more likely to receive treatment.

Association between Fat Distribution and Chronic Low Back Pain among 10,606 Adults: Data from the Korean National Health and Nutrition Examination Survey

Obesity is associated with chronic low back pain (CLBP), but the association between fat distribution and CLBP is unclear. This cross-sectional study evaluated the relationship using the Korean National Health and Nutrition Examination Survey data. A total of 10,606 adults (average age: 45.4, female: 57.1%) were included. We estimated the regional fat distribution, waist circumference, and body fat proportion, compared the values in people with and without CLBP, and stratified the estimates by sex and obesity status using a multivariable linear model. There were no statistically significant differences in the average waist circumference between the people with and without CLBP (p = 0.731) and the average fat proportion between those with and without CLBP (p = 0.731). The average regional fat distribution was significantly higher in the people with CLBP than in those without CLBP, in the upper limbs (11.4%, 95% confidence interval [CI]: [11.3, 11.5] vs. 11.2%, 95% CI: [11.1, 11.3], p < 0.05) and in the lower limbs (31.9%, 95% CI: [31.6, 32.2] vs. 31.4%, 95% CI: [31.2, 31.6], p < 0.01). More obvious among men, fat distribution in the lower limbs is higher than in people without obesity (p < 0.001). People with CLBP tend to have a higher fat distribution in the limbs than those without it and obese people with CLBP would need to reduce the fat in the lower limbs.

Risk factors for low back pain outcome: Does it matter when they are measured?

BACKGROUND

The early identification of factors that increase risk of poor recovery from acute low back pain (LBP) is critical to prevent the transition to chronicity. Although most studies of risk factors for poor outcome in LBP tend to investigate the condition once it is already persistent, there is evidence to suggest that this differs from risk factors measured during the early-acute stage. This study aimed to identify early risk factors for poor outcome in the short- and long-term in individuals with acute LBP, and to compare this with factors identified at 3 months in the same cohort.

METHODS

One hundred and thirty-three individuals were recruited within 2 weeks of an acute LBP episode and completed questionnaires related to their sociodemographic, psychological, clinical and history/treatment status at baseline and 3 months later, and their pain-level fortnightly for 12 months.

RESULTS

Of the 133 participants recruited, follow-up data was provided by 120 at 3 months, 97 at 6 months, 85 at 9 months and 94 at 12 months. Linear regression identified various factors at baseline (acute phase) and 3 months later that predicted short- and long-term outcome (pain level, change in pain). Key findings were that: (1) depressive symptoms at baseline most consistently predicted worse outcome; (2) psychological factors in general at 3 months were more predictive of outcome than when measured at baseline; (3) early health care utilisation predicted better outcome, whereas use of pain medication later (3 months) predicted worse outcome; and (4) sex and BMI predicted outcome inconsistently over 12-months.

CONCLUSIONS

The results highlight the multidimensional nature of risk factors for poor outcome in LBP and the need to consider time variation in these factors.

Investigating Individuals’ Perceptions Regarding the Context Around the Low Back Pain Experience: Topic Modeling Analysis of Twitter Data

Background

Low back pain (LBP) remains the leading cause of disability worldwide. A better understanding of the beliefs regarding LBP and impact of LBP on the individual is important in order to improve outcomes. Although personal experiences of LBP have traditionally been explored through qualitative studies, social media allows access to data from a large, heterogonous, and geographically distributed population, which is not possible using traditional qualitative or quantitative methods. As data on social media sites are collected in an unsolicited manner, individuals are more likely to express their views and emotions freely and in an unconstrained manner as compared to traditional data collection methods. Thus, content analysis of social media provides a novel approach to understanding how problems such as LBP are perceived by those who experience it and its impact.

Objective

The objective of this study was to identify contextual variables of the LBP experience from a first-person perspective to provide insights into individuals’ beliefs and perceptions.

Methods

We analyzed 896,867 cleaned tweets about LBP between January 1, 2014, and December 31, 2018. We tested and compared latent Dirichlet allocation (LDA), Dirichlet multinomial mixture (DMM), GPU-DMM, biterm topic model, and nonnegative matrix factorization for identifying topics associated with tweets. A coherence score was determined to identify the best model. Two domain experts independently performed qualitative content analysis of the topics with the strongest coherence score and grouped them into contextual categories. The experts met and reconciled any differences and developed the final labels.

Results

LDA outperformed all other algorithms, resulting in the highest coherence score. The best model was LDA with 60 topics, with a coherence score of 0.562. The 60 topics were grouped into 19 contextual categories. “Emotion and beliefs” had the largest proportion of total tweets (157,563/896,867, 17.6%), followed by “physical activity” (124,251/896,867, 13.85%) and “daily life” (80,730/896,867, 9%), while “food and drink,” “weather,” and “not being understood” had the smallest proportions (11,551/896,867, 1.29%; 10,109/896,867, 1.13%; and 9180/896,867, 1.02%, respectively). Of the 11 topics within “emotion and beliefs,” 113,562/157,563 (72%) had negative sentiment.

Conclusions

The content analysis of tweets in the area of LBP identified common themes that are consistent with findings from conventional qualitative studies but provide a more granular view of individuals’ perspectives related to LBP. This understanding has the potential to assist with developing more effective and personalized models of care to improve outcomes in those with LBP.

Does Patient Body Mass Index Affect the Outcome of Multimodal Rehabilitation in Chronic Mechanical Low Back Pain?

STUDY DESIGN

Retrospective.

OBJECTIVE

The aim of this study was to investigate the effect of body mass index (BMI) on pain and disability in patients with chronic mechanical low back pain (LBP) treated with multimodal rehabilitation.

SUMMARY OF BACKGROUND DATA

Despite being a well-known risk factor for developing LBP, there is minimal data on the effect of BMI on pain and disability in patients with chronic mechanical low back pain (LBP) treated with multimodal rehabilitation.

METHODS

Data from patients with chronic mechanical LBP who underwent multimodal rehabilitation treatment at a chain of spine rehabilitation outpatient clinics in one of the three BMI groups-1564 patients in normal body weight (BMI ≥18.5-24.9), 1990 patients in overweight (BMI ≥25-29.9), and 891 patients in obese (BMI ≥ 30) groups-were retrospectively analyzed. Pre- and post-treatment Numerical Pain Rating Scale (NPRS) and Oswestry Disability Index (ODI) scores, and final treatment outcomes were compared between the three groups. Multivariate analysis was used to determine the association between pre-treatment covariates and post-treatment clinical outcomes.

RESULTS

Post-treatment, the mean NPRS (P = 0.005) and mean ODI (P < 0.001) scores were significantly higher with a significantly lower percentage of full success outcome (P = 0.009) in the obese group when compared to normal and overweight groups. However, multivariate analysis showed a significant correlation between age, the number of treatment sessions, pre-treatment NPRS and ODI scores, and post-treatment NPRS and ODI scores and treatment failure, and no correlation with patient BMI.

CONCLUSION

Patient BMI may not affect pain and disability outcomes in patients undergoing a multimodal rehabilitation treatment for chronic LBP. In contrast to BMI, other covariates such as age, treatment sessions, and pre-treatment NPRS and ODI scores may be associated with increased risk for poor treatment outcome. Obese individuals can expect clinical outcomes similar to normal or overweight individuals with multimodal physical rehabilitation for chronic LBP.Level of Evidence: 3.

Is adiposity associated with back and lower limb pain? A systematic review

BACKGROUND

Back and lower limb pain have a major impact on physical function and quality of life. While obesity is a modifiable risk factor for musculoskeletal pain, the role of adiposity is less clear. This systematic review aimed to examine the relationship between both adiposity and its distribution and back and lower limb pain.

METHODS

A systematic search of electronic databases was conducted to identify studies that examined the association between anthropometric and/or direct measures of adiposity and site specific musculoskeletal pain. Risk of bias was assessed and a best evidence synthesis was performed.

RESULTS

A total of 56 studies were identified which examined 4 pain regions, including the lower back (36 studies), hip (two studies), knee (13 studies) and foot (eight studies). 31(55%) studies were assessed as having low to moderate risk of bias. 17(30%) studies were cohort in design. The best evidence synthesis provided evidence of a relationship between central adiposity and low back and knee pain, but not hip or foot pain. There was also evidence of a longitudinal relationship between adiposity and the presence of back, knee and foot pain, as well as incident and increasing foot pain.

CONCLUSIONS

This systematic review provides evidence of an association between both body fat and its central distribution and low back and knee pain, and a longitudinal relationship between adiposity and back, knee and foot pain. These results highlight the potential for targeting adiposity in the development of novel treatments at these sites.

Clusters of Physical Frailty and Cognitive Impairment and Their Associated Comorbidities in Older Primary Care Patients

(1) Objectives: We aimed to identify clusters of physical frailty and cognitive impairment in a population of older primary care patients and correlate these clusters with their associated comorbidities. (2) Methods: We used a latent class analysis (LCA) as the clustering technique to separate different stages of mild cognitive impairment (MCI) and physical frailty into clusters; the differences were assessed by using a multinomial logistic regression model. (3) Results: Four clusters (latent classes) were identified: (1) highly functional (the mean and SD of the “frailty” test 0.58 ± 0.72 and the Mini-Mental State Examination (MMSE) test 27.42 ± 1.5), (2) cognitive impairment (0.97 ± 0.78 and 21.94 ± 1.95), (3) cognitive frailty (3.48 ± 1.12 and 19.14 ± 2.30), and (4) physical frailty (3.61 ± 0.77 and 24.89 ± 1.81). (4) Discussion: The comorbidity patterns distinguishing the clusters depend on the degree of development of cardiometabolic disorders in combination with advancing age. The physical frailty phenotype is likely to exist separately from the cognitive frailty phenotype and includes common musculoskeletal diseases.

Circulating Adipokines in Predicting the Transition from Acute to Persistent Low Back Pain

OBJECTIVES

Cytokines such as tumor necrosis factor (TNF) contribute to the transition from acute to persistent pain. Despite increasing incidence of obesity and its linkage with chronic pain and inflammation, cytokines predominantly produced by adipose tissue (adipokines) have received little attention. Here we aimed to explore the longitudinal trajectory of adipokines from the onset of acute low back pain (LBP) and identify combinations of adipokines and/or other features that predict outcome.

METHODS

Individuals with acute LBP (less than two weeks after onset) who had either recovered (no pain, N = 15) or remained unrecovered (no reduction/increase in pain, N = 13) at six months and 15 controls were retrospectively selected from a larger prospective cohort. Participants provided blood for the measurement of TNF, interleukin-6 (IL-6), resistin, visfatin, adiponectin, leptin, and C-reactive protein (CRP), and completed questionnaires related to pain/disability, depression, and sleep at baseline. LBP participants repeated measurements at six months.

RESULTS

Compared with controls, acute LBP individuals had higher TNF and CRP but lower adiponectin. In LBP, unrecovered individuals had higher TNF at both time points, but lower CRP at baseline and leptin at six months. Although combined low CRP, high TNF, and depressive symptoms at baseline predicted poor recovery, the primary adipokines leptin, resistin, visfatin, and adiponectin did not.

CONCLUSIONS

Primary adipokines did not add to the prediction of poor LBP outcome that has been identified for the combination of low CRP, high TNF, and depressive symptoms in acute LBP. Whether adipokines play a role in LBP persistence in overweight/obese individuals requires investigation.

Efficacy of the lumbar stabilization and thoracic mobilization exercise program on pain intensity and functional disability reduction in chronic low back pain patients with lumbar radiculopathy: A randomized controlled trial

BACKGROUND

Exercise programs in the treatment of chronic lumbar pain are quite diverse, but it has been proven that stabilization exercises are the most effective.

OBJECTIVE

We compared the lumbar stabilization exercise program in a closed and open kinetic chain (LSCO) and lumbar stabilization exercises and thoracic mobilization program in a closed kinetic chain (LSTMC), and evaluated the clinical effectiveness of each program.

METHODS

Prospective, randomized, controlled trial in 80 chronic low back pain (CLBP) patients with lumbar radiculopathy of both sexes (35 male, 45 female), average age (48.45 ± 10.22 years), divided in two groups that performed different sets of exercises. Participants were given laser therapy, transcutaneous electro-nerve stimulation and an eight-week kinesiotherapy that included exercises to strengthen the deep lumbar spine stabilizers. Retesting was done after four and eight weeks.

RESULTS

Statistically significant (p< 0.05) superior recovery of the LSTMC group subjects compared to the LSCO group was achieved at all measurement intervals in the pain intensity and functional disability parameters.

CONCLUSION

Patients who performed the lumbar stabilization and thoracic mobilization exercise program in a closed kinetic chain had the most effective reduction of pain intensity and functional disability.

Does vitamin D status influence lumbar disc degeneration and low back pain in postmenopausal women? A retrospective single-center study

OBJECTIVE

To investigate the relationship between serum vitamin D concentration and lumbar disc degeneration (LDD) in postmenopausal women and the epidemiologic factors affecting low back pain (LBP).

METHODS

Between July 2017 and December 2018, 232 participants were retrospectively enrolled. Serum concentrations of bone turnover markers were measured using electrochemiluminescence assays. Disc degeneration was evaluated using the Pfirrmann grading system. Other variables were assessed using relevant questionnaires.

RESULTS

The mean age of the women was 65.6 ± 10.1 and their serum 25(OH)D concentrations were 19.38 ± 9.21 ng/mL. The prevalences of severe vitamin D deficiency (<10 ng/mL) and normal status (>30 ng/mL) were 12.9% and 12.5%, respectively. The severely deficient group had higher visual analog scale (VAS) scores for LBP (P = 0.002) and lower bone mineral density T scores (P = 0.004) than the other groups. Lower 25(OH)D concentration (<10 ng/mL) was significantly associated with more severe LDD in the lumbosacral region (L4-S1, L1-S1, P < 0.05), but less so in the upper lumbar region. There was an inverse relationship between vitamin D concentration and the severity of disc degeneration (L2-L3, L4-S1, L1-S1, P < 0.05). After adjustment for confounding factors, smoking, vitamin D deficiency, lack of vitamin D supplementation, high body mass index, and low bone mineral density T score were associated with higher incidence of moderate-to-severe pain in postmenopausal women (P < 0.05).

CONCLUSIONS

Vitamin D deficiency is associated with LDD and LBP in postmenopausal women. Specifically, a serum vitamin D concentration < 10 ng/mL is a marker of severe LDD and LBP. Smoking, severe vitamin D deficiency, lack of vitamin D supplementation, high body mass index, and osteoporosis are associated with a higher prevalence of moderate-to-severe pain.

Influence of dynamic preoperative body mass index changes on patient-reported outcomes after surgery for degenerative lumbar spine disease

Psychological factors demonstrably and often massively influence outcomes of degenerative spine surgery, and one could hypothesize that preoperative weight loss may correlate with motivation and lifestyle adjustment, thus leading to potentially enhanced outcomes. We aimed to evaluate the effect of preoperative weight loss or gain, respectively, on patient-reported outcomes after lumbar spine surgery. Weight loss was defined as a BMI decrease of ≤ − 0.5 kg/m² over a period of at least 1 month, and weight gain as a BMI increase of ≥ 0.5 kg/m² in the same time period, respectively. The primary endpoint was set as the achievement of the minimum clinically important difference (MCID) in the ODI at 1 or 2 years postoperatively. A total of 154 patients were included. Weight loss (odds ratio (OR): 1.18, 95% confidence interval (CI): 0.52 to 2.80) and weight gain (OR: 1.03, 95% CI: 0.43 to 2.55) showed no significant influence on MCID achievement for ODI compared to a stable BMI. The same results were observed when analysing long-term NRS-BP and NRS-LP. Regression analysis showed no correlation between BMI change and PROM change scores for any of the three PROMs. Adjustment for age and gender did not alter results. Our findings suggest that both preoperative weight loss and weight gain may have no measurable effect on long-term postoperative outcome compared to a stable BMI. Weight loss preoperatively—as a potential surrogate sign of patient motivation and lifestyle change—may thus not influence postoperative outcomes.

Intervertebral Disc Regeneration Using Stem Cell/Growth Factor-Loaded Porous Particles with a Leaf-Stacked Structure

Although biological therapies based on growth factors and transplanted cells have demonstrated some positive outcomes for intervertebral disc (IVD) regeneration, repeated injection of growth factors and cell leakage from the injection site remain considerable challenges for human therapeutic use. Herein, we prepare human bone marrow-derived mesenchymal stem cells (hBMSCs) and transforming growth factor-β3 (TGF-β3)-loaded porous particles with a unique leaf-stack structural morphology (LSS particles) as a combination bioactive delivery matrix for degenerated IVD. The LSS particles are fabricated with clinically acceptable biomaterials (polycaprolactone and tetraglycol) and procedures (simple heating and cooling). The LSS particles allow sustained release of TGF-β3 for 18 days and stable cell adhesiveness without additional modifications of the particles. On the basis of in vitro and in vivo studies, it was observed that the hBMSCs/TGF-β3-loaded LSS particles can provide a suitable milieu for chondrogenic differentiation of hBMSCs and effectively induce IVD regeneration in a beagle dog model. Thus, therapeutically loaded LSS particles offer the promise of an effective bioactive delivery system for regeneration of various tissues including IVD.

BMI influences relationships among health factors for adults with persistent pain who use prescription opioids

BACKGROUND

Long-term use of prescription opioids for pain results in negative health outcomes. Overweight and pain are related, and adults with either condition commonly report poor sleep quality, high levels of depression, low levels of self-efficacy, and high pain interference and intensity. Insufficient research exists regarding how weight may influence pain outcomes in the context of common symptoms.

PURPOSE

To investigate how body mass index (BMI) influences relationships between health factors and pain outcomes among adults with pain prescribed opioids.

METHODS

The sample included 226 adults. Linear regression models tested relationships among variables and outcomes of pain intensity and pain interference.

FINDINGS

BMI significantly strengthened relationships between health factors and pain interference but not pain intensity.

DISCUSSION

Adults with persistent pain suffer worsened pain interference in the context of increased weight status. Nurses should consider addressing BMI as part of a holistic pain management care plan.

A prediction model of low back pain risk: a population based cohort study in Korea

Background

Well-validated risk prediction models help to identify individuals at high risk of diseases and suggest preventive measures. A recent systematic review reported lack of validated prediction models for low back pain (LBP). We aimed to develop prediction models to estimate the 8-year risk of developing LBP and its recurrence.

Methods

A population based prospective cohort study using data from 435,968 participants in the National Health Insurance Service–National Sample Cohort enrolled from 2002 to 2010. We used Cox proportional hazards models.

Results

During median follow-up period of 8.4 years, there were 143,396 (32.9%) first onset LBP cases. The prediction model of first onset consisted of age, sex, income grade, alcohol consumption, physical exercise, body mass index (BMI), total cholesterol, blood pressure, and medical history of diseases. The model of 5-year recurrence risk was comprised of age, sex, income grade, BMI, length of prescription, and medical history of diseases. The Harrell’s C-statistic was 0.812 (95% confidence interval [CI], 0.804-0.820) and 0.916 (95% CI, 0.907-0.924) in validation cohorts of LBP onset and recurrence models, respectively. Age, disc degeneration, and sex conferred the highest risk points for onset, whereas age, spondylolisthesis, and disc degeneration conferred the highest risk for recurrence.

Conclusions

LBP risk prediction models and simplified risk scores have been developed and validated using data from general medical practice. This study also offers an opportunity for external validation and updating of the models by incorporating other risk predictors in other settings, especially in this era of precision medicine.

Physical fitness, musculoskeletal disorders and body mass index in transport drivers from Barranquilla, Colombia

Introduction: Sedentary work activities in urban transport drivers are associated with overweight and obesity, an increase in musculoskeletal discomfort related to work and a decrease in physical fitness.Objective: To determine physical fitness and musculoskeletal discomfort in urban transport drivers from Barranquilla, Colombia, based on their body mass index (BMI).Material and Methods: Cross-sectional study conducted in 231 urban transport drivers. Healthy physical fitness and presence of musculoskeletal symptoms were measured using the AFISAL-INEFC test battery and the Nordic Questionnaire developed by Kuorinka, respectively.Results: There were significant differences between drivers with normal BMI and overweight/obese drivers in abdominal strength and endurance (21.4±8.9 vs. 19.6±8.8 stooped, p=0.04), flexibility (36.1±7.3 cm vs. 33.6±7.1 cm, p=0.02), and aerobic capacity (1537.5±704.8 meters vs. 1249.1±346.6 meters, p=0.0001). Increased frequency of musculoskeletal discomfort was observed in subjects with BMI >25 kg/m2.Conclusions: Overweight and obesity are associated with poor physical fitness and the perception of musculoskeletal discomfort, which has negative implications for the personal and occupational well-being of these workers, generating a burden for companies and the Colombian health system.

High baseline fat mass, but not lean tissue mass, is associated with high intensity low back pain and disability in community-based adults

Objectives

Low back pain is the largest contributor to disability worldwide. The role of body composition as a risk factor for back pain remains unclear. Our aim was to examine the relationship between fat mass and fat distribution on back pain intensity and disability using validated tools over 3 years.

Methods

Participants (aged 25–60 years) were assessed at baseline using dual-energy X-ray absorptiometry (DXA) to measure body composition. All participants completed the Chronic Pain Grade Scale at baseline and 3-year follow-up. Of the 150 participants, 123 (82%) completed the follow-up.

Results

Higher baseline body mass index (BMI) and fat mass (total, trunk, upper limb, lower limb, android, and gynoid) were all associated with high intensity back pain at either baseline and/or follow-up (total fat mass: multivariable OR 1.05, 95% CI 1.01–1.09, p < 0.001). There were similar findings for all fat mass measures and high levels of back disability. A higher android to gynoid ratio was associated with high intensity back pain (multivariable OR 1.04, 95% CI 1.01–1.08, p = 0.009). There were no associations between lean mass and back pain.

Conclusions

This cohort study provides evidence for the important role of fat mass, specifically android fat relative to gynoid fat, on back pain and disability.

Epidemiological Aspects of Low Back Pain

Low back pain (LBP) is a major health problem, particularly in the contemporary societies of highly developed countries. This study seeks to define the influence of basic demographic and social factors, such as gender, body mass, physical activity, and the type of work, on the occurrence of lumbosacral spine pain in the early and middle-late adulthood. The study was based on a self-reported survey, using the revised Oswestry Low Back Pain Disability Questionnaire to evaluate pain symptoms, and managing everyday tasks. Physical activity was evaluated on the Minnesota Leisure Time Physical Activity Questionnaire. We found that patients in the early adulthood had a significantly lower level of disability. The older patients had a greater low back pain and motion, sleeping, and social life problems. Neither did gender nor the type of work, leisure time physical activity, or body mass appreciably affect the level of disability due to low back pain in both younger and older patient groups. We conclude that, all else unchanged from the epidemiological standpoint, wear and tear of the spine structure naturally progressing with age seems a major determinant of the appearance of low back pain.

Vitamin D supplementation may improve back pain disability in vitamin D deficient and overweight or obese adults

Back pain is currently the greatest cause of disability worldwide, and there are very limited therapeutic options available. Vitamin D deficiency and obesity are both risk factors for back pain. The few randomised controlled trials examining the effects of vitamin D supplementation on back pain have methodological limitations and largely include non-vitamin D deficient participants. Thus, the aim of this study was to determine whether vitamin D supplementation improves back pain symptoms in vitamin D deficient and overweight or obese, otherwise healthy adults. Sixty-five overweight or obese adults (BMI ≥ 25 kg/m²) with vitamin D deficiency (25-hydroxyvitamin D [25(OH)D] concentrations ≤50 nmol/L) were randomised to a bolus oral dose of 100,000 IU followed by 4000 IU cholecalciferol/day or matching placebo for 16 weeks. We measured 25(OH)D concentrations (chemiluminescent immunoassays) and self-reported back pain (Chronic Pain Grade Questionnaire) before and after the intervention. Lifestyle habits including sun exposure, physical activity, and diet were collected using questionnaires. Fifty-four participants completed the study, of which 49 had complete data for back pain and were included in the present analyses (31 M/18 F; mean ± SD age: 31.8 ± 8.9 years; BMI: 31.1 ± 4.5 kg/m²). After the 16-week intervention, 25(OH)D levels increased significantly with vitamin D supplementation compared with placebo (55.7 ± 20.9 versus 3.9 ± 14.4 nmol/L, respectively, p < 0.001). There were no significant differences between vitamin D and placebo groups in change in back pain intensity or disability scores (all p > 0.05). However, in those with 25(OH)D concentrations <30 nmol/L at baseline (n = 20), there was a significantly greater reduction in back pain disability scores in the vitamin D group compared with placebo, after adjusting for important covariates known to affect vitamin D status and/or back pain (b [95%CI] = -11.6 [-22.4, -0.8], p = 0.04). Our findings suggest that vitamin D supplementation in overweight or obese and markedly vitamin D deficient adults (25(OH)D <30 nmol/L) may improve back pain disability. Although treating severe vitamin D deficiency is recommended for optimising bone health, this study suggests it may also improve back pain. Hence, testing for vitamin D deficiency in those with back pain who are overweight or obese may be warranted.

The association between body fat and musculoskeletal pain: a systematic review and meta-analysis

BACKGROUND

Obesity and musculoskeletal pain are strongly related, but there is emerging evidence that body fat, not body weight, may be a better indicator of risk. There is, therefore, a need to determine if body fat is associated with musculoskeletal pain as it may improve management strategies. The aim of this systematic review was to investigate the association between body fat and musculoskeletal pain.

METHODS

Seven electronic databases were searched from inception to 8th January 2018. Cross-sectional and longitudinal studies investigating the association between measures of body fat and musculoskeletal pain were included. All included articles were assessed for methodological rigour using the Epidemiology Appraisal Instrument. Standardised mean differences (SMDs) and effect estimates were pooled for meta-analysis.

RESULTS

A total of 10,221 citations were identified through the database searching, which after abstract and full-text review, yielded 28 unique articles. Fourteen studies were included in the meta-analyses, which found significant cross-sectional associations between total body fat mass and widespread pain (SMD 0.49, 95% CI 0.37-0.61, p < 0.001). Individuals with low-back pain and knee pain had a higher body fat percentage than asymptomatic controls (SMD 0.34, 95% CI 0.17-0.52, p < 0.001 and SMD 0.18, 95% CI 0.05-0.32, p = 0.009, respectively). Fat mass index was significantly, albeit weakly, associated with foot pain (SMD 0.05, 95% CI 0.03-0.06, p < 0.001). Longitudinal studies (n = 8) were unsuitable for meta-analysis, but were largely indicative of elevated body fat increasing the risk of incident and worsening joint pain. There was conflicting evidence for an association between body fat percentage and incident low-back pain (3 studies, follow-up 4-20 years). Increasing knee pain (1 study) and incident foot pain (2 studies) were positively associated with body fat percentage and fat mass index. The percentage of items in the EAI graded as 'yes' for each study ranged from 23 to 85%, indicating variable methodological quality of the included studies.

CONCLUSIONS

This systematic review and meta-analysis identified positive cross-sectional associations between increased body fat and widespread and single-site joint pain in the low-back, knee and foot. Longitudinal studies suggest elevated body fat may infer increased risk of incident and worsening joint pain, although further high-quality studies are required.

Machine-learning-derived classifier predicts absence of persistent pain after breast cancer surgery with high accuracy

Background

Prevention of persistent pain following breast cancer surgery, via early identification of patients at high risk, is a clinical need. Supervised machine-learning was used to identify parameters that predict persistence of significant pain.

Methods

Over 500 demographic, clinical and psychological parameters were acquired up to 6 months after surgery from 1,000 women (aged 28–75 years) who were treated for breast cancer. Pain was assessed using an 11-point numerical rating scale before surgery and at months 1, 6, 12, 24, and 36. The ratings at months 12, 24, and 36 were used to allocate patents to either “persisting pain” or “non-persisting pain” groups. Unsupervised machine learning was applied to map the parameters to these diagnoses.

Results

A symbolic rule-based classifier tool was created that comprised 21 single or aggregated parameters, including demographic features, psychological and pain-related parameters, forming a questionnaire with “yes/no” items (decision rules). If at least 10 of the 21 rules applied, persisting pain was predicted at a cross-validated accuracy of 86% and a negative predictive value of approximately 95%.

Conclusions

The present machine-learned analysis showed that, even with a large set of parameters acquired from a large cohort, early identification of these patients is only partly successful. This indicates that more parameters are needed for accurate prediction of persisting pain. However, with the current parameters it is possible, with a certainty of almost 95%, to exclude the possibility of persistent pain developing in a woman being treated for breast cancer.

Electronic supplementary material

The online version of this article (10.1007/s10549-018-4841-8) contains supplementary material, which is available to authorized users.

Musculoskeletal pain profile of obese individuals attending a multidisciplinary weight management service

Obesity is associated with numerous chronic diseases, including musculoskeletal (MSK) pain, which affects on quality of life (QoL). There is, however, limited research providing a comprehensive MSK pain profile of an obese cohort. This retrospective study used a patient database at a national weight management service. After ethical approval, anonymized patient data were statistically analyzed to develop a pain profile, investigate relationships between pain, sleep, and function, and explore variables associated with having low back pain (LBP) and knee pain. Overall, 915 individuals attended the weight management service from January 2011 to September 2015 [male, 35% (n = 318; confidence interval [CI] = 32-38); female, 65% (n = 597; CI = 62-68); mean age 44.6]. Mean body mass index was 50.7 kg/m [class III obese (body mass index ≥40 kg/m), 92% (n = 835; CI = 91-94)]. Approximately 91% reported MSK pain: LBP, 69% (n = 539; CI = 65-72) [mean Numeric Rating Scale 7.4]; knee pain, 58% (n = 447; CI = 55-61) [mean Numeric Rating Scale 6.8]. Class III obese and multisite pain patients had lower QoL and physical activity levels, reduced sleep, and poorer physical function than less obese patients and those without pain (P < 0.05). Relationships were found between demographic, pain, self-report, psychological, and functional measures (P < 0.05). Patients who slept fewer hours and had poorer functional outcomes were more likely to have LBP; patients who were divorced, had lower QoL, and more frequent nocturia were more likely to have knee pain (P < 0.05). Multisite MSK pain is prevalent and severe in obese patients and is negatively associated with most self-report and functional outcomes. This high prevalence suggests that pain management strategies must be considered when treating obesity.

The fat mass index, not the fat-free mass index, is associated with impaired physical performance in older adult subjects: Evidence from a cross-sectional study

BACKGROUND

Impaired physical performance (IPP) and physical disability (PD) are two serious public health problems in older adult populations worldwide. While studies show that changes in body composition are important risk factors for developing these conditions, there is little evidence that the fat-free mass (FFM) and fat mass (FM) indices (FFMI and FMI, respectively) are associated with IPP in older men and women. This study assessed the association among FFMI, FMI, and IPP using Short Physical Performance Battery (SPPB) in Mexican men and women aged over 60 years.

METHODS

This cross-sectional study included 217 older people (men 34.6%, women 65.4%; 60-92 years). FFM and FM were assessed by dual X-ray absorptiometry, assuming a two-compartment model. FFM and FM were adjusted by height squared and the indices were obtained. After assessment of physical performance by SPPB, subjects with scores ≤6 were classified as having IPP. Associations were tested by multiple logistic regression analysis in separated models.

RESULTS

IPP prevalence was 14.3%. Women were affected more than men. Regression analysis showed no significant association between FFMI and IPP, but FMI was strongly-associated, as for each unit increase in FMI, the risk of IPP rose significantly (OR: 1.14), and this result remained significant after adjusting for age, comorbidity, polypharmacy, and the appendicular skeletal muscle mass index (OR: 1.23; p ≤ 0.001). These results emphasize the importance of preventing increases in FM and avoiding overweight and obesity in older men and women.

Adipsin Concentrations Are Associated with Back Pain Independently of Adiposity in Overweight or Obese Adults

Objective: To compare cardiometabolic risk factors including cytokine and adipokine concentrations between individuals with and without back pain. Methods: In 62 overweight/obese adults (BMI ≥ 25 kg/m2; 23F/39M), we collected data on: self-reported back pain; anthropometry [BMI, waist circumference, body composition (dual energy X-ray absorptiometry-DEXA)]; metabolic parameters [fasting glucose; insulin sensitivity (hyperinsulinaemic-euglycaemic clamps)]; cardiovascular parameters (blood pressure, lipids); serum inflammation markers [high-sensitivity C-reactive protein (hsCRP; immunoturbidimetric-assay), tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6, and IL-10 (multiplex-assay)]; and adipokines [leptin, adipsin, resistin, and adiponectin (multiplex-assay)]. Results: Participants who reported having back pain in the past month (n = 24; 39%) had higher BMI (mean ± SD = 33.8 ± 6.3 vs. 30.2 ± 4.1 kg/m2, p = 0.008), fat-mass (39.9 ± 12.3 vs. 33.9 ± 9.8%, p = 0.04), and waist circumference (109.6 ± 16.8 vs. 101.0 ± 9.3 cm, p = 0.01) compared to those without back pain (n = 38; 61%). No differences were observed in cardiometabolic parameters, inflammatory markers, or adiponectin or resistin concentrations. Those reporting back pain had higher adipsin concentrations compared to those without back pain [median (IQR) = 744 (472-2,804) vs. 721 (515-867) ng/ml, p = 0.03], with a trend for higher leptin [5.5 (1.5-24.3) vs. 2.3 (1.5-6.7) ng/ml, p = 0.05], both of which persisted after adjustment for age and sex. Adipsin remained associated with back pain independently of adiposity (BMI, waist, fat-mass, or total %body fat; all p ≤ 0.03). Conclusions: Greater obesity, and higher adipsin and leptin concentrations were observed in those who reported back pain in the past month compared to those without back pain, and adipsin was associated with back pain independently of adiposity. Larger studies are needed to determine if adipsin could be a novel therapeutic target for prevention and/or treatment of back pain.

Analysis of intra and extramyocellular lipids in the multifidus muscle in patients with chronic low back pain using MR spectroscopy

OBJECTIVE

To analyse the intra- (IMCL) and extramyocellular lipids (EMCL) concentration in the multifidus muscle (Mm) using MR spectroscopy (MRS) in patients with low back pain (LBP), and to evaluate the correlation between those lipid concentrations and age, obesity, atrophy of the Mm and LBP intensity.

METHODS

60 LBP patients underwent routine diagnostic MRI of the lumbar spine before undergoing imaging for the study. Body mass index, as an indicator of obesity and visual analogue scale, as an indicator of LBP were also measured. Proton MRS was acquired with a single-voxel point-resolved spectroscopy sequence. Furthermore, the MRS volume of interest for measuring the IMCL and EMCL concentration at L4/5 for the right Mm was determined, and we measured the cross-sectional area of Mm as an indicator of muscle atrophy.

RESULTS

Age showed correlation with EMCL concentration (r = 0.314, p = 0.008). The body mass index showed correlation with EMCL concentration (r = 0.358, p = 0.005). The cross-sectional area of Mm showed correlation with EMCL concentration (r = -0.543, p < 0.001). Moreover, the LBP visual analogue scale showed correlation with IMCL concentration (r = 0.367, p = 0.004).

CONCLUSION

There were correlations between age, obesity, muscle atrophy, and EMCL concentration in Mm. IMCL concentration in Mm showed a correlation with LBP intensity. This may suggest that IMCL concentration could become an effective objective indicator of chronic LBP intensity. Advances in knowledge: We investigated the characteristics of fat content in Mm with LBP patients. This study was demonstrated the association of the IMCL and EMCL concentration in Mm with various patient parameters.

A Comparison of the Sociodemographic and Clinical Characteristics of Patients Referring to a Pain Clinic with Subacute and Chronic Pain

OBJECTIVES

The aim of the present study was to assess and compare the sociodemographic characteristics and clinical features of patients referring to a university hospital's pain clinic with chronic ( ≥ 12 weeks) and subacute pain ( < 12 weeks).

METHODS

In this cross-sectional study, 426 patients were included. Demographic variables including education level, marital and employment status, and risk factors such as obesity, diabetes mellitus, hypertension, cigarette smoking, and opium addiction were recorded. Also, sites of pain, pain quality and associated symptoms, and pain severity were assessed using a numerical rating scale. Each one of these variables was compared between the chronic and subacute pain groups.

RESULTS

Of the 426 studied patients, 292 (69%) had chronic pain and 134 (31%) reported subacute pain. Patients with chronic pain were older and had higher body mass indices. Additionally, self-employment was less frequent among the chronic pain group. The patients with chronic pain had a higher prevalence of addiction. The most commonly reported site of pain in all patients was the lower back (62.4%), followed by pain in the leg and foot (39.9%), knee (24.4%), and hip (18.8%). There were no statistically significant differences in pain sites between the two groups, except for knee pain, which was more common among the chronic pain group. The patients with chronic pain had a higher incidence of obscure and persistent pain, while those with subacute pain experienced more night pain.

CONCLUSIONS

About one-third of the patients referring to the pain clinic had subacute pain. The patients with chronic pain were older and more obese, had a higher prevalence of addiction, had more cases of knee pain, and reported more instances of obscure and persistent pain than those with subacute pain.

Fat mass and fat distribution are associated with low back pain intensity and disability: results from a cohort study

Background

Determining the association between body composition and low back pain (LBP) will improve our understanding of the mechanisms by which obesity affects LBP, and inform novel approaches to managing LBP. The aim of this study was to examine the relationship between body composition and LBP intensity and disability.

Methods

A total of 5058 participants (44% men) of the Australian Diabetes, Obesity and Lifestyle Study were assessed for LBP intensity and disability using the Chronic Pain Grade Questionnaire (2013–2014). Body mass index (BMI) and waist circumference were directly obtained. Fat mass and percentage fat were estimated from bioelectrical impedance analysis at study inception (1999–2000).

Results

Eighty-two percent of participants reported LBP, of whom 27% also reported LBP disability. BMI, waist circumference, percent fat, and fat mass were each positively associated with LBP intensity and disability at 12 years after adjustment for potential confounders. LBP intensity and disability showed significant dose-responses to sex-specific quartiles of BMI, waist circumference, percent fat and fat mass. For example, the adjusted OR for LBP intensity in women increased with increasing fat mass quartiles [Q1: 1, Q2: 1.05 (95%CI 0.84–1.32); Q3: 1.25 (1.00–1.57); and Q4: 1.78 (1.42–2.24); p < 0.001].

Conclusions

Fat mass and distribution are associated with LBP intensity and disability, suggesting systemic metabolic factors associated with adiposity play a major role in the pathogenesis of LBP. Clarifying the mechanisms will facilitate developing novel preventive and therapeutic approaches for LBP.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-017-1242-z) contains supplementary material, which is available to authorized users.

The effect of obesity on treatment outcomes for low back pain

Background

The objective of this study was to estimate the effect of obesity, as measured by body mass index (BMI), on treatment outcomes for low back pain (LBP).

Methods

Data from the University of California, Los Angeles, and Friendly Hills Healthcare Network low back pain study (collected from 1995 to 2000) were used to perform a secondary data analysis of this randomized clinical trial on adults who sought care for LBP. BMI was the primary predictor variable. Binary logistic regression modeling was performed to estimate odds ratios adjusted for the effects of confounders.

Results

Using normal weight as the referent population, underweight and overweight populations did not display significant odds ratios for any of the outcome variables. The obese population demonstrated odds ratios of 0.615 (0.379, 0.998) for improvement of disability and 0.550 (0.341, 0.889) for improvement of most severe back pain.

Conclusion

The results of this study support an association between obesity and less effective treatment outcomes whether measured by disability (Roland-Morris scale) or pain (most severe pain NRS). Overweight and underweight populations do not appear to have significantly different outcomes than normal weight populations.

Trial registration

This trial was designed and conducted prior to the advent of registries.