Psychosocial factors and risk of chronic widespread pain: an 11-year follow-up study--the HUNT study

Few studies have used prospective designs in large population surveys to assess the risk of developing chronic widespread pain (CWP). We wanted to examine 1) how many people without CWP developed it after 11years, and 2) how anxiety, depression, alcohol use, smoking, sleeping problems, and body mass index (BMI) were associated with this development. This study was based on a representative population-based Norwegian cohort attending both the second (1995 to 1997) and the third (2006 to 2008) wave of the Nord-Trøndelag Health Study (HUNT2 and HUNT3, respectively). Only those adults attending both surveys (N=28,367) were included. Approximately 19,000 individuals without CWP in HUNT2 were assessed for later CWP development in HUNT3, where we looked for symptoms of anxiety, depression, monthly frequency of alcohol use, smoking, sleeping problems, and BMI. Data were analyzed with logistic regression adjusted for age, sex, education, marital status, physical exercise, and pain symptoms not meeting the CWP criteria at baseline. After 11 years, 12% of those without CWP developed CWP. Anxiety and depression, former and current smoking status, BMI<18.5 kg/m(2), BMI⩾25 kg/m(2), and sleeping problems were all associated with an increased risk of CWP. High and moderate levels of alcohol use were associated with a reduced risk of CWP. In summary, this study indicates that CWP develops over a long-term period for a substantial group of healthy people, and that both psychosocial and lifestyle factors influence the risk of CWP onset.