Sleep quality and chronic neck pain: A cotwin study

Abstract

Study Objectives: Sleep quality and chronic neck pain (NP) are associated. However, the genetic influences on this association have not been explored. This study investigated the genetic and environmental influences on the association between sleep quality and chronic NP. Methods: The sample comprised 2,328 individual twins fromthe Murcia Twin Registry (Spain). A bidirectional cotwin logistic regression analysis was performed (sleep quality assessed as the exposure and chronic NP as the outcome and vice versa). Analysis included 2 sequential stages: Total sample analysis and within-pair twin case-control analysis. Results: Sleep quality was significantly associated with chronic NP in the total sample analysis (adjusted odds ratio [OR]: 1.09; 95%confidence interval [CI]: 1.06, 1.12; P