Skip to main content

Table 1 Baseline characteristics*

From: Reduced hypothalamic-pituitary-adrenal axis activity in chronic multi-site musculoskeletal pain: partly masked by depressive and anxiety disorders

  Controls Chronic pain P† N ~
  (n = 654) (n = 471)   
Pain
Days of pain in the prior 6 months 28.3 ± 49.1 109.0 ± 69.9 <0.001  
Pain intensity 21.5 ± 14.7 52.3 ± 17.7 <0.001  
Pain disability 9.4 ± 13.2 38.1 ± 24.9 <0.001  
Cortisol sampling factors
Time of awakening 7:23 ± 1:07 7:34 ± 1:10 0.01  
Working on day of sampling, % 67.2 48.5 <0.001  
Sampling in month with more daylight, % 52.7 54.4 0.50  
≤6 h sleep, % 21.0 37.3 <0.001  
Sociodemographic factors
Age, years 43.3 ± 13.4 46.7 ± 11.8 <0.001  
Women, % 56.7 73.5 <0.001  
Education, years 13.1 ± 3.3 11.6 ± 3.3 <0.001  
Lifestyle and disease factors
Body mass index, kg/m2 25.0 ± 4.2 26.2 ± 4.8 <0.001  
Smoking, %    0.05  
Never smoker 32.0 27.2   
Former smoker 39.0 37.2   
Current smoker 29.1 35.7   
Alcohol use, %    <0.001  
Non-drinker 20.9 38.2   
Mild/moderate drinker 66.2 50.7   
Heavy drinker 12.8 11.0   
Physical activity, 1000 MET min./week 3.6 ± 3.0 3.9 ± 3.1 0.06  
Number of chronic diseases 0.6 ± 0.8 0.9 ± 0.9 <0.001  
Depression and anxiety factors
Lifetime depressive or anxiety disorder, %    <0.001  
No disorder 40.4 12.7   
Depressive disorder 19.0 16.8   
Anxiety disorder 13.1 10.0   
Comorbid depressive/anxiety disorder 27.5 60.5   
Current depressive or anxiety disorder, % 35.9 67.5 <0.001  
Antidepressant medication, %    <0.001  
No antidepressant 83.2 71.3   
SSRI 10.9 20.0   
TCA 2.1 2.3   
Other antidepressant 3.8 6.4   
Cortisol measures
At awakening, nmol/l, median [IQR] 15.88 [12.42-20.17] 15.48 [12.07-19.45] 0.10 1105
AUCg, nmol/l/h 19.0 ± 7.0 18.8 ± 6.7 0.55 1025
AUCi, nmol/l/h 1.9 ± 6.5 2.6 ± 6.2 0.09 1025
Mean evening level, nmol/l, median [IQR] 4.68 [3.23-6.34] 4.90 [3.38-6.83] 0.07 1120
Diurnal slope, decline in nmol/l/h 0.77 ± 0.49 0.71 ± 0.39 0.05 1001
Cortisol suppression ratio, median [IQR] 2.43 [1.75-3.33] 2.35 [1.70-3.12] 0.23 1061
  1. MET = metabolic equivalent; SSRI = selective serotonin reuptake inhibitor; TCA = tricyclic antidepressant.
  2. AUCg = area under the curve with respect to the ground; AUCi = area under the curve with respect to the increase.
  3. * Values are mean ± SD unless otherwise indicated. †Based on independent-sample T test for continuous
  4. variables, chi-square test for dichotomous and categorical variables and Mann-Whitney U test for non-normally distributed variables. ~N-values that vary from total N = 1125 due to missings on individual cortisol measures.
Back to article page

BMC Musculoskeletal Disorders

ISSN: 1471-2474

Contact us