title: Serum beta-endorphin in primary fibromyalgia syndrome: a controlled study.
abstract: Serum beta-endorphin was assayed without knowledge of study subject category in 44 consecutive patients with primary fibromyalgia syndrome, 3 patients with rheumatoid arthritis (RA), and 30 normal controls, all females. Mean serum beta-endorphin levels were 81 +/- 28 pg/ml in patients with fibromyalgia, whereas those in normal controls and patients with RA were 73 +/- 17 pg/mg and 73 +/- 18 pg/ml, respectively. These differences were not statistically significant. Serum beta-endorphin levels did not correlate with relevant clinical variables in either fibromyalgia or RA groups.
mesh_terms: D000293:Adolescent; D000328:Adult; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000503:physiopathology; D002940:Circadian Rhythm; D004723:Endorphins / Q000097:blood*; D005260:Female; D006801:Humans; D008875:Middle Aged; D010146:Pain; D012216:Rheumatic Diseases / Q000097:blood* / Q000503:physiopathology; D012621:Seasons; D013577:Syndrome; D001615:beta-Endorphin
chemical_list: D004723:Endorphins; D001615:beta-Endorphin