Interaction between serotonin transporter gene-linked polymorphic region (5-HTTLPR) and job-related stress in insomnia: a cross-sectional study in Sichuan, China

Sleep Med. 2014 Oct;15(10):1269-75. doi: 10.1016/j.sleep.2014.01.023. Epub 2014 Jun 14.

Abstract

Objective: Insomnia, a widely occurring sleep disorder in modern society, has a large impact on life quality and work safety. A cross-sectional study was conducted to explore the possible link between serotonin transporter-linked polymorphic region (5-HTTLPR), job-related stress, and insomnia in West China.

Methods: Of the total 462 workers recruited, 177 had insomnia according to the Athens Insomnia Scale (AIS-5). The 5-HTTLPR genotypes were determined by polymerase chain reaction. Job-related stress was assessed for each participant by the General Job Stress Questionnaire.

Results: Unconditional logistic regression models showed that the 5-HTTLPR genotype was significantly associated with insomnia, and >80% increased risk per S allele was observed. High job-related stress had a higher risk for insomnia than low job-related stress (odds ratio [OR], 6.14; 95% confidence interval [CI], 3.94-9.59). Crossover analysis found significant job-related stress × 5-HTTLPR interaction. Compared to individuals with both low job-related stress and SL/LL genotype, those with both higher job-related stress and SS genotype had a higher risk of insomnia (OR, 5.16; 95% CI, 3.13-8.54), whereas those with both low job-related stress and SS genotype showed a lower risk of insomnia (OR, 0.26; 95% CI, 0.08-0.74). The interaction remained statistically significant after adjusting for potential confounding factors.

Conclusions: The findings indicated that 5-HTTLPR could modify the effect of job-related stress on employees' insomnia, suggesting that a work environment-based personalized intervention may be applied to prevent employees' insomnia by alleviating job-related stress in the workplace.

Keywords: 5-HTTLPR; Employee; Environment–gene interaction; Genotype; Insomnia; Job-related stress; Susceptibility; Workplace.

MeSH terms

  • Adult
  • Alleles
  • China / epidemiology
  • Cross-Sectional Studies
  • Employment / psychology
  • Female
  • Genotype
  • Humans
  • Male
  • Middle Aged
  • Polymorphism, Genetic / genetics
  • Polymorphism, Genetic / physiology
  • Serotonin Plasma Membrane Transport Proteins / genetics*
  • Serotonin Plasma Membrane Transport Proteins / physiology
  • Sleep Initiation and Maintenance Disorders / epidemiology
  • Sleep Initiation and Maintenance Disorders / etiology
  • Sleep Initiation and Maintenance Disorders / genetics*
  • Stress, Psychological / complications*
  • Surveys and Questionnaires

Substances

  • SLC6A4 protein, human
  • Serotonin Plasma Membrane Transport Proteins