title: Is Chronic Low Back Pain Associated with the Prevalence of Coronary Heart Disease when Genetic Susceptibility Is Considered? A Co-Twin Control Study of Spanish Twins.
abstract: To investigate the chronic low back pain and coronary heart disease relationship, after adjusting for relevant confounders, including genetics.
  
  
  
  In a cross-sectional design, 2148 twins were recruited from the Murcia Twin Registry, Spain. The exposure was chronic LBP and the outcomes were myocardial infarction and other coronary heart diseases-lifetime and in the last 2 years-based on standardized health-related questionnaires. First, logistic regression analysis investigated associations of the total sample followed by a matched co-twin control analyses, with all complete twin pairs discordant for chronic LBP utilised, separated for zygosity-dizygotic (DZ) and monozygotic (MZ) pairs, which adjusted for shared familial factors, including genetics.
  
  
  
  Chronic LBP pain is associated with lifetime myocardial infarction [odds ratio (OR) = 2.69, 95% confidence interval (CI) = 1.35-5.36], other coronary heart diseases over a lifetime (OR = 2.58, 95% CI: 1.69-3.93) and in the last two years (OR = 2.19, 95% CI: 1.33-3.60), while there was a borderline association with myocardial infarction in the last 2 years (OR = 2.64, 95% CI: 0.98-7.12). Although the magnitude of the association remained or increased in the co-twin control analyses, none reached statistical significance.
  
  
  
  Chronic LBP is associated with a higher prevalence of myocardial infarction and coronary heart disease. It is possible that this association remains even when controlling for genetics and early shared environment, although this should be investigated with larger samples of twins discordant for LBP.
authors.affiliation: Arthritis & Musculoskeletal Research Group, Faculty of Health Sciences, The University of Sydney, Sydney, Australia.
authors.forename: Matt
authors.initials: M
authors.lastname: Fernandez
authors.affiliation: Murcia Twin Registry, Department of Human Anatomy and Psychobiology, University of Murcia and IMIB-Arrixaca, Murcia, Spain.
authors.forename: Juan R
authors.initials: JR
authors.lastname: Ordoñana
authors.affiliation: Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense M, Denmark.|Nordic Institute of Chiropractic and Clinical Biomechanics, University of Southern Denmark, Odense M, Denmark.
authors.forename: Jan
authors.initials: J
authors.lastname: Hartvigsen
authors.affiliation: Musculoskeletal Division, The George Institute for Global Health, Sydney Medical School, The University of Sydney, Sydney, Australia.|Institute of Bone and Joint Research, The Kolling Institute, Sydney Medical School, The University of Sydney, NSW, Australia.
authors.forename: Manuela L
authors.initials: ML
authors.lastname: Ferreira
authors.affiliation: Arthritis & Musculoskeletal Research Group, Faculty of Health Sciences, The University of Sydney, Sydney, Australia.
authors.forename: Kathryn M
authors.initials: KM
authors.lastname: Refshauge
authors.affiliation: Murcia Twin Registry, Department of Human Anatomy and Psychobiology, University of Murcia and IMIB-Arrixaca, Murcia, Spain.
authors.forename: Juan F
authors.initials: JF
authors.lastname: Sánchez-Romera
authors.affiliation: Arthritis & Musculoskeletal Research Group, Faculty of Health Sciences, The University of Sydney, Sydney, Australia.
authors.forename: Marina B
authors.initials: MB
authors.lastname: Pinheiro
authors.affiliation: Charles Perkins Centre, School of Biological Sciences, The University of Sydney, Sydney, Australia.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Simpson
authors.affiliation: Australian Twin Registry, Centre for Molecular, Environmental, Genetic, and Analytic Epidemiology, The University of Melbourne, Victoria, Australia.
authors.forename: John L
authors.initials: JL
authors.lastname: Hopper
authors.affiliation: Arthritis & Musculoskeletal Research Group, Faculty of Health Sciences, The University of Sydney, Sydney, Australia.
authors.forename: Paulo H
authors.initials: PH
authors.lastname: Ferreira
mesh_terms: D016022:Case-Control Studies; D059350:Chronic Pain / Q000150:complications* / Q000235:genetics*; D016001:Confidence Intervals; D003327:Coronary Disease / Q000150:complications* / Q000453:epidemiology*; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D017116:Low Back Pain / Q000150:complications* / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000150:complications; D016017:Odds Ratio; D015995:Prevalence; D013030:Spain; D014427:Twins / Q000235:genetics*