@article{Vassend_Orvik_Czajkowski_Røysamb_2016, title={Facets of neuroticism and musculoskeletal symptoms. A study of middle-aged twins}, volume={26}, url={https://www.ntnu.no/ojs/index.php/norepid/article/view/2015}, DOI={10.5324/nje.v26i1-2.2015}, abstractNote={Clinical and epidemiological studies have shown that both site-specific and more widespread musculoskeletal<br />(MS) conditions are linked to anxiety and depression symptoms. However, the nature of this relationship is<br />poorly understood, particularly in terms of underlying genetic and environmental influences. Furthermore, the<br />personality trait neuroticism has been shown to be related to common emotional symptoms and somatic<br />distress as well as to more serious psychiatric and medical disorders. In modern personality theory, the broad<br />neuroticism domain is conceptualized as consisting of a set of lower-order facets, such as anxiety, hostility,<br />and depression, which may be differentially related to various health outcome measures. So far, the role of<br />neuroticism facets as risk factors for MS conditions has not been explored in genetically informative designs.<br />In the current study, the relationship between MS symptoms and six neuroticism facets was investigated in<br />bivariate analyses and in regression models including sex, education level, and general health indices as<br />control variables. Using multivariate twin modeling, genetic and environmental influences on the phenotypes<br />and the associations among them were determined. The sample consisted of 746 monozygotic (MZ) and 770<br />dizygotic (DZ) twins in the age group of 50-65 (mean = 57.11 years, SD = 4.5). The results showed that a<br />single factor accounted for about 50% of the overall variance in MS symptom reporting. Two neuroticism<br />facets, N1: anxiety and N3: depression, appeared as significant in the regression analyses. Both these facets<br />and MS symptoms were strongly influenced by genetic factors [heritability (h2) = 0.46-0.54]. While there was<br />a considerable overlap in genetic risk factors between the three phenotypes, a large proportion (71%) of the<br />genetic variance in MS symptoms was unique to the phenotype, and not shared with the neuroticism facets.}, number={1-2}, journal={Norsk Epidemiologi}, author={Vassend, Olav and Orvik, Benedicte Humborstad and Czajkowski, Nikolai Olavi and Røysamb, Espen}, year={2016}, month={Jul.} }