Svetlana Solovieva

The Association Between Obesity and Low Back Pain: A Meta-Analysis

This meta-analysis assessed the association between overweight/obesity and low back pain. The authors systematically searched the Medline (National Library of Medicine, Bethesda, Maryland) and Embase (Elsevier, Amsterdam, the Netherlands) databases until May 2009. Ninety-five studies were reviewed and 33 included in the meta-analyses. In cross-sectional studies, obesity was associated with increased prevalence of low back pain in the past 12 months (pooled odds ratio (OR) = 1.33, 95% confidence interval (CI): 1.14, 1.54), seeking care for low back pain (OR = 1.56, 95% CI: 1.46, 1.67), and chronic low back pain (OR = 1.43, 95% CI: 1.28, 1.60). Compared with non-overweight people, overweight people had a higher prevalence of low back pain but a lower prevalence of low back pain compared with obese people. In cohort studies, only obesity was associated with increased incidence of low back pain for > or =1 day in the past 12 months (OR = 1.53, 95% CI: 1.22, 1.92). Results remained consistent after adjusting for publication bias and limiting the analyses to studies that controlled for potential confounders. Findings indicate that overweight and obesity increase the risk of low back pain. Overweight and obesity have the strongest association with seeking care for low back pain and chronic low back pain.

The association between smoking and low back pain: a meta-analysis.

OBJECTIVE To assess the association between smoking and low back pain with meta-analysis. METHODS We conducted a systematic search of the MEDLINE and EMBASE databases until February 2009. Eighty-one studies were reviewed and 40 (27 cross-sectional and 13 cohort) studies were included in the meta-analyses. RESULTS In cross-sectional studies, current smoking was associated with increased prevalence of low back pain in the past month (pooled odds ratio [OR] 1.30, 95% confidence interval [CI], 1.16-1.45), low back pain in the past 12 months (OR 1.33, 95% CI, 1.26-1.41), seeking care for low back pain (OR 1.49, 95% CI, 1.38-1.60), chronic low back pain (OR 1.79, 95% CI, 1.27-2.50) and disabling low back pain (OR 2.14, 95% CI, 1.11-4.13). Former smokers had a higher prevalence of low back pain compared with never smokers, but a lower prevalence of low back pain than current smokers. In cohort studies, both former (OR 1.32, 95% CI, 0.99-1.77) and current (OR 1.31, 95% CI, 1.11-1.55) smokers had an increased incidence of low back pain compared with never smokers. The association between current smoking and the incidence of low back pain was stronger in adolescents (OR 1.82, 95% CI, 1.42-2.33) than in adults (OR 1.16, 95% CI, 1.02-1.32). CONCLUSIONS Our findings indicate that both current and former smokers have a higher prevalence and incidence of low back pain than never smokers, but the association is fairly modest. The association between current smoking and the incidence of low back pain is stronger in adolescents than in adults.

Possible association of interleukin 1 gene locus polymorphisms with low back pain

&NA; Based on a hypothesis that interleukin 1 (IL‐1) activity is associated with low back pain (LBP), we investigated relationships between previously described functional IL‐1 gene polymorphisms and LBP. The subjects were a subgroup of a Finnish study cohort. The IL‐1&agr;(C889–T), IL‐1&bgr;(C3954–T) and IL‐1 receptor antagonist (IL‐1RN)(G1812–A, G1887–C and T11100–C) polymorphisms were genotyped in 131 middle‐aged men from three occupational groups (machine drivers, carpenters and office workers). A questionnaire inquired about individual and lifestyle characteristics and the occurrence of LBP, the number of days with pain and days with limitation of daily activities because of pain, and pain intensity, during the past 12 months. Lumbar disc degeneration was determined with magnetic resonance imaging. Carriers of the IL‐1RNA1812 allele had an increased risk of LBP (OR 2.5, 95% CI 1.0–6.0) and carriers of this allele in combination with the IL‐1&agr;T889 or IL‐1&bgr;T3954 allele had a higher risk of and more days with LBP than non‐carriers. Pain intensity was associated with the simultaneous carriage of the IL‐1&agr;T889 and IL‐1RNA1812 alleles (OR 3.7, 95% CI 1.2–11.9). Multiple regression analyses allowing for occupation and disc degeneration showed that carriage of the IL‐1RNA1812 allele was associated with the occurrence of pain, the number of days with pain and days with limitations of daily activities. Carriage of the IL‐1&bgr;T3954 allele was associated with the number of days with pain. The results suggest a possible contribution of the IL‐1 gene locus polymorphisms to the pathogenesis of LBP. The possibility of chance findings cannot be excluded due to the small sample size.

Interleukin 1 polymorphisms and intervertebral disc degeneration.

Background: Enzymatic breakdown of the extracellular matrix, and possibly local inflammation, contributes to intervertebral disc degeneration. We investigated whether polymorphisms within the IL-1 gene locus are associated with lumbar disc degeneration and whether the effect of occupational physical load on disc degeneration is modified by the polymorphisms. Methods: Genotypes were determined from 133 middle-aged men who underwent magnetic resonance imaging of the lumbar spine. The participants represented 3 occupations: 40 were machine drivers, 42 carpenters, and 51 office workers. We evaluated decreased signal intensity of the nucleus pulposus, disc bulges, and decreased disc height as signs of degeneration in the L2/L3–L5/S1 discs. Results: The odds ratio for disc bulges was 2.4 (95% confidence interval = 1.2– 4.8) and 1.9 (1.0–3.7), in carriers of the IL-1αT889 or IL-1βT3954 alleles, respectively. The TT genotype of the IL-1α gene carried more than 3-fold risk of disc bulges as compared with the CC genotype. Conclusions: IL-1 gene cluster polymorphisms could affect the risk of disc degeneration. The effect of physical workload seems to be modified by the IL-1 gene polymorphisms.

Intervertebral disc degeneration in relation to the COL9A3 and the IL-1ß gene polymorphisms

Disc degeneration is a complex condition in which environmental factors and multiple genes are expected to act together to determine the degenerative phenotype. Recently associations of COL9A2 (Trp2 allele) and COL9A3 (Trp3 allele) polymorphisms with lumbar disc disease characterized by sciatica have been reported. However, it is not known whether the Trp2 or Trp3 alleles contribute to disc degeneration (DD). In this study, the association between the collagen genes polymorphisms and lumbar DD was investigated. Furthermore, the influence of the IL-1β(C3954-T) polymorphism on the association of collagen genes polymorphisms with DD was examined. Lumbar intervertebral discs of 135 middle-aged occupationally active men were evaluated with magnetic resonance imaging, using decreased signal intensity of the nucleus pulposus, disc bulges, and decreased disc height as signs of degeneration. Blood samples were analysed for the presence of COL9A3 and COL9A2 tryptophan alleles (Trp3 and Trp2 alleles). The COL11A2, COL2A1 and IL-1β(C3954-T) polymorphisms were also analysed. Multivariate logistic regression analysis allowing for occupation and body mass index showed that the carriage of the Trp3 allele in the absence of the IL-1βT3954 allele increased the risk of dark nucleus pulposus (OR 7.0, 95% CI 1.3–38.8) and joint occurrence of degenerative changes (OR 8.0, 95% CI 1.4–44.7). There was no effect of the Trp3 allele on DD in the presence of the IL-1βT3954 allele. The carriers of the COL11A2 minor allele had an increased risk of disc bulges (OR 2.1, 95% CI 1.0–4.2) as compared with non-carriers. The results suggest that the effect of the COL9A3 gene polymorphism on DD might be modified by the IL-1β gene polymorphism.

Leisure time physical activity and strenuousness of work as predictors of physical functioning: a 28 year follow up of a cohort of industrial employees

Aims: To examine associations of leisure time physical activity and physical strenuousness of work with physical functioning 28 years later. Methods: A cohort (n = 902) of metal industry employees was studied for exercise and housework activity in 1973 and 1978, and for BMI, current smoking, strenuousness of work, grip strength, and chronic diseases in 1973. Of the 670 survivors in 2000, 529 (79%) responded to all studied items in a follow up questionnaire including the SF-36 Physical Functioning (PF) scale. Belonging to the lower quartile of the PF scale denoted poor functioning. Results: Vigorous exercise and housework activity were inversely associated with poor PF 28 years later in both white-collar and blue-collar workers. Engaging in activities of any intensity was similarly associated among the blue-collar workers. In a multiple logistic regression model including as independent variables age, sex, occupational class, the number of chronic diseases, vigorous leisure time physical activity, BMI, physical work strenuousness, and smoking (all measured at baseline), the risk of poor PF at follow up was decreased by vigorous leisure time physical activity and increased by high physical strenuousness of work, high BMI, and smoking. The effect of work strenuousness was mainly due to that among the blue-collar group. Allowing for baseline grip strength did not materially alter the results. Conclusion: Vigorous leisure time physical activity decreased the risk of poor physical functioning as perceived considerably later in life, while high work strenuousness, smoking, and overweight increased it. Among blue-collar workers a beneficial association was observed with all leisure time activity, including that of lower intensity.

Cardiovascular and lifestyle risk factors in lumbar radicular pain or clinically defined sciatica: a systematic review.

Lumbar radicular pain is a fairly common health problem, yet its risk factors are far from clear. There are no published systematic reviews on associations between cardiovascular or lifestyle risk factors and lumbar radicular pain or sciatica. The aim of this systematic literature review was to assess associations between these risk factors and lumbar radicular pain or sciatica. We conducted a systematic search of the Medline database for all original articles on lumbar radicular pain or sciatica published until August 2006. Twenty-two papers from 19 studies were included in the review. Overweight or obesity was associated with sciatica in most of the case-control and cohort studies. Some studies showed an increased risk of lumbar radicular pain in smokers with a long smoking history or in those with high levels of physical activity. A few case-control studies showed an association between serum C-reactive protein and sciatica. No consistent associations were found for serum lipids levels or high blood pressure. In summary, the associations of overweight, long smoking history, high physical activity and a high serum C-reactive protein level with lumbar radicular pain or sciatica were substantiated by the present review. However, more prospective studies are needed in order to further clarify these associations and the mechanisms of action.

Psychosocial factors at work, long work hours, and obesity: a systematic review

OBJECTIVES Associations between psychosocial work environment and excess weight have not been systematically addressed. The aim of this systematic review was to summarize the published evidence for the associations of psychosocial factors at work and long work hours with weight-related outcomes . Methods We conducted a search of Medline and Embase for all original articles published up to September 2012 using predefined keywords. After excluding studies with a definite selection bias, we included 39 articles. RESULTS About 60% of the studies reported at least one positive association between psychosocial factors at work and a weight-related outcome. However, 76% of the tested associations were found to be non-significant. Furthermore, the associations were rather weak. Studies of higher quality tended to observe associations more often than those of lower quality. Positive associations were found more frequently (i) among women versus men, (ii) in cross-sectional versus longitudinal studies, and (iii) for overweight or obesity versus other outcomes. About 70% of the studies reported positive associations between long work hours and weight-related outcomes. All four studies that evaluated the association between working overtime and weight gain (three longitudinal and one cross-sectional), showed a positive association among men and two of them also observed associations among women. CONCLUSIONS We found evidence for weak associations between psychosocial factors at work and excess weight. Associations were observed between long work hours, working overtime, and weight gain, especially among men. More cohort studies among non-obese baseline participants using appropriate analytical methods based on an elaborated hypothetical model are needed.

Genetic Association Studies in Lumbar Disc Degeneration: A Systematic Review

Objective Low back pain is associated with lumbar disc degeneration, which is mainly due to genetic predisposition. The objective of this study was to perform a systematic review to evaluate genetic association studies in lumbar disc degeneration as defined on magnetic resonance imaging (MRI) in humans. Methods A systematic literature search was conducted in MEDLINE, MEDLINE In-Process, SCOPUS, ISI Web of Science, The Genetic Association Database and The Human Genome Epidemiology Network for information published between 1990–2011 addressing genes and lumbar disc degeneration. Two investigators independently identified studies to determine inclusion, after which they performed data extraction and analysis. The level of cumulative genetic association evidence was analyzed according to The HuGENet Working Group guidelines. Results Fifty-two studies were included for review. Forty-eight studies reported at least one positive association between a genetic marker and lumbar disc degeneration. The phenotype definition of lumbar disc degeneration was highly variable between the studies and replications were inconsistent. Most of the associations presented with a weak level of evidence. The level of evidence was moderate for ASPN (D-repeat), COL11A1 (rs1676486), GDF5 (rs143383), SKT (rs16924573), THBS2 (rs9406328) and MMP9 (rs17576). Conclusions Based on this first extensive systematic review on the topic, the credibility of reported genetic associations is mostly weak. Clear definition of lumbar disc degeneration phenotypes and large population-based cohorts are needed. An international consortium is needed to standardize genetic association studies in relation to disc degeneration.

Risk factors of atherosclerosis and shoulder pain--is there an association? A systematic review.

Background: Shoulder pain is prevalent and a common cause of disability at work and daily activities. Some studies suggest an association between risk factors of atherosclerosis and shoulder pain and disorders.