Introduction Chronic musculoskeletal pain represents a significant health problem among adults in Norway. The prevalence of chronic pain can be up to 50% in both genders. However, the prevalence of chronic widespread pain is significantly higher in females than in males. Chronic widespread pain is seen as the end of a continuum of pain. There is rather sparse knowledge about the incidence of pain in initially pain free individuals and the course of self-reported pain over time. Moreover, little is known about risk factors for incidence of chronic pain or prognostic factors for the course of self-reported pain. We believe that such knowledge may contribute to develop strategies for treatment at an early stadium of the pain condition and thereby reduce the prevalence of chronic pain included chronic widespread pain. Aims of the study The aims of this study were threefold: (1) to calculate the incidence of self-reported musculoskeletal pain in a female cohort, (2) to describe the course of pain and (3) to investigate whether or not health complaints and sleep problems are predictive factors for onset of pain or prognostic factors for the course of pain. Methods This is a prospective population-based study of all women between 20 and 50 years who were registered in Arendal, Norway, in 1989 (N = 2498 individuals). A questionnaire about chronic pain (pain >3 months duration in muscles, joints, back or the whole body), modulating factors for pain, sleep problems and seven non-specific health complaints was mailed to all traceable women, in 1990 (N =2498), 1995 (n = 2435) and 2007 (n = 2261). Of these, 1338 responded on all three occasions. Outcome measures were presence and extent of chronic pain. Results The prevalence of chronic pain was 57% in 1990 and 61% in 2007. From 1990 to 2007, 53% of the subjects changed pain category. The incidence of chronic pain in initially pain free individuals during follow-up was 44%, whereas the recovery rate was 25%. Impaired sleep quality predicted onset of chronic pain. There was a linear association between the number of health complaints and the incidence of chronic pain in initially pain free individuals. Equivalent results were found for persistence of pain and worsening of pain. Conclusion The prevalence of chronic pain was rather stable throughout the follow-up period, but the prevalence of chronic widespread pain increased. Individual changes in pain extent occurred frequently. The presence of sleep disturbances and number of health complaints predicted onset, persistence and worsening of pain. Implications Sleep problems must be thoroughly addressed as a possible risk factor for onset or worsening of pain. Elimination of sleep problems in an early phase is an interesting approach in treating chronic pain. More research is needed to illuminate the possible pathogenetic relations between pain, non-specific health complaints, sleep problems and also depression.

In order to investigate the significance and outcome of self-reported pain and fibromyalgia (FM) in a female population, 214 women with initially self-reported pain were interviewed and examined in 1990 and 1995. In 1990 the sample was categorised into four pain status groups: 46 individuals (21%) with nonchronic (recurrent) pain, 69 (32%) with chronic regional pain 42 (20%) with chronic multifocal pain and 57 with chronic widespread pain (CWP). The last group comprised 39 (18%) women with FM, fulfilling the American College of Rheumatology 1990 criteria. The frequency of tender points, associated symptoms called historical variables and individuals with low education increased statistically significantly with increasing pain status. In 1995, 48 women had non-chronic pain (23%), 46 (21%) chronic regional pain, 39 (18%) chronic multifocal pain and 81 (38%) CWP; of these, 71 (33%) had FM. Eleven of the 39 women initially with FM no longer fulfilled the criteria. The risk of developing CWP among the 157 individuals with initially a lower pain status was statistically higher in women with chronic multifocal pain than in women with less pain extension. Self-reported pain constitutes a continuum of pain severity and thus of clinical and social significance. The overall outcome was poor with an increase of individuals with CWP and FM. The prognosis of chronic multifocal pain, CWP and FM was especially poor. About half of the women with non-chronic pain or chronic regional pain did not deteriorate. However, because the process of developing FM started with localised pain in most cases, self-reported pain of any severity confers a risk for developing FM. Identifying possible risk factors for FM are at present under study and will be presented separately in another report.

Aabstract Introduction Chronic musculoskeletal pain represents a significant health problem among adults in Norway. The prevalence of chronic pain is reported to be 35-53% in cross sectional studies of both genders. For many years, it has been a common opinion among medical doctors that chronic pain may indeed reduce a person's quality of life, but not affect life expectancy. However, over the previous two decades, reports about mortality and cause of death in individuals with chronic pain have been published. So far, several studies conclude that there is an increased mortality in patients with chronic pain, but it is not clear what causes this. Increased occurrences of cardio-vascular death or cancer death have been reported in some studies, but not verified in other studies. Aims of the study The aims of this study were to estimate the mortality rate in females with different extent of pain, to identify potential risk factors for death and to investigate if the causes of death differ according to prior reported pain. Methods This is a prospective population-based study of all women between 20 and 50 years registered in Arendal, Norway, in 1989 (N = 2498 individuals). At follow-up in 2007, 2261 living females were retraced, 89 had died. All subjects received a questionnaire containing questions about chronic pain (pain ≥ 3 months duration in muscles, joints, back or the whole body) as well as 13 sub-questions about pain-modulating factors, non-specific health complaints and sleep problems, by mail in 1990, 1995 and 2007. Only subjects who answered the questionnaire in 1990 were included in the analyses. Of the deceased, 71 had answered the questionnaire in 1990. A multivariate model for cox regression analysis was used in order to clarify if chronic pain, sleep problems, feeling anxious, frightened or nervous and number of unspecific health were risk factors for death. The causes of death of 87 of the deceased individuals were obtained by linking the ID-number with the Norwegian Cause of Death Registry. Results The ratio of deceased responders was 2% (14/870) among those with no pain versus 5% (57/1168) among those with chronic pain at baseline. When separating into chronic regional pain and chronic widespread pain, the mortality rate was respectively 4% and 8% in the different groups. Age adjusted hazard ratio for mortality rate in individuals with initially chronic pain was [HR 2.5 (CI 1.4-4.5)] compared to pain free individuals. In the multivariate analysis, having chronic pain [HR 2.1 (1.1-4.2)] and feeling anxious, frightened or nervous [HR 3.2 (1.8-5.6)] were associated with increased risk of death. There was no difference in death from cardiovascular disease or malignancies between the groups of pain free individuals vs. the group of individuals with chronic pain. Conclusion The mortality rate was significantly higher for individuals with chronic pain compared to pain free individuals, adjusted for age. In addition, feeling anxious, frightened or nervous were risk factors for death. There was an increase...

Objectives. Studies assessing relative mortality risks across the spectrum of systemic inflammatory rheumatic diseases are largely missing. In this study, we wanted to estimate standard mortality ratios (SMRs) and causes of death in an ethnically homogeneous cohort covering all major CTDs and primary systemic vasculitides (PSVs). Methods. We prospectively followed all incident CTD and PSV cases included in the Norwegian CTD and vasculitis registry (NOSVAR) between 1999 and 2015. Fifteen controls for each patient matched for sex and age were randomly drawn from the Norwegian National Population Registry. Causes of death were obtained from the National Cause of Death Register, death certificates and hospital charts.Results. The cohort included 2140 patients (1534 with CTD, 606 with PSV). During a mean follow-up time of 9 years, 279 of the patients (13%) died, compared with 2864 of 32 086 (9%) controls (P < 0.001). Ten years after diagnosis, the lowest survival was 60% in dcSSc, 73% in anti-synthetase syndrome (ASS) and 75% in lcSSc. In the CTD group, the highest SMRs were observed in dcSSc (SMR 5.8) and ASS (SMR 4.1). In the PSV group, Takayasu arteritis (SMR 2.5) and ANCAassociated vasculitis (SMR 1.5) had the highest SMRs. Major causes of death were cardiovascular disease (CTD 27%, PSV 28%), neoplasms (CTD 25%, PSV 27%), chronic respiratory disease (CTD 20%, PSV10%) and infections (CTD 9%, PSV 16%). Conclusion.We observed premature deaths across the spectrum of CTDs and PSVs, with highest SMRs in dcSSc and ASS. The overall mortality was highest in the CTD group.