Fibromyalgia and Related Conditions. Clauw DJ. Mayo Clin Proc. 2015 May;90(5):680-692. doi: 10.1016/j.mayocp.2015.03.014. Abstract Fibromyalgia is the currently preferred term for widespread musculoskeletal pain, typically accompanied by other symptoms such as fatigue, memory problems, and sleep and mood disturbances, for which no alternative cause can be identified. Earlier there was some doubt about whether there was an "organic basis" for these related conditions, but today there is irrefutable evidence from brain imaging and other techniques that this condition has strong biological underpinnings, even though psychological, social, and behavioral factors clearly play prominent roles in some patients. The pathophysiological hallmark is a sensitized or hyperactive central nervous system that leads to an increased volume control or gain on pain and sensory processing. This condition can occur in isolation, but more often it co-occurs with other conditions now being shown to have a similar underlying pathophysiology (eg, irritable bowel syndrome, interstitial cystitis, and tension headache) or as a comorbidity in individuals with diseases characterized by ongoing peripheral damage or inflammation (eg, autoimmune disorders and osteoarthritis). In the latter instance, the term centralized pain connotes the fact that in addition to the pain that might be caused by peripheral factors, there is superimposed pain augmentation occurring in the central nervous system. It is important to recognize this phenomenon (regardless of what term is used to describe it) because individuals with centralized pain do not respond nearly as well to treatments that work well for peripheral pain (surgery and opioids) and preferentially respond to centrally acting analgesics and nonpharmacological therapies. PDF
Comparación en el mundo real de servicios de salud de la utilización entre duloxetina y pregabalina en iniciadores con fibromialgia.
Real-world comparison of health care utilization between duloxetine and pregabalin initiators with fibromyalgia. Peng X, Sun P, Novick D, Andrews J1, Sun S. J Pain Res. 2014 Jan 9;7:37-46. doi: 10.2147/JPR.S51636. eCollection 2014. Abstract OBJECTIVES: To compare health care utilization of duloxetine initiators and pregabalin initiators among fibromyalgia patients in a real-world setting. METHODS: A retrospective cohort study was conducted based on a US national commercial health claims database (2006-2009). Fibromyalgiapatients who initiated duloxetine or pregabalin in 2008, aged 18-64 years, and who maintained continuous health insurance coverage 1 year before and 1 year after initiation were assigned to duloxetine or pregabalin cohorts on the basis of their initiated agent. Patients who had pill coverage of the agents over the course of 90 days preceding the initiation were excluded. The two comparative cohorts were constructed using propensity score greedy match methods. Descriptive analysis and paired t-test were performed to compare health care utilization rates in the postinitiation year and the changes of these rates from the preinitiation year to the postinitiation year. RESULTS: Both matched cohorts (n=1,265 pairs) had a similar mean initiation age (49-50 years), percentage of women (87%-88%), and prevalence of baseline comorbid conditions (neuropathic pain other than diabetic peripheral neuropathic pain, low back pain, cardiovascular disease, hypertension, headache or migraine, and osteoarthritis). In the preinitiation year, both cohorts had similar inpatient, outpatient, and medication utilization rates (inpatient, 15.7%-16.1%; outpatient, 100.0%; medication, 97.9%-98.7%). The utilization rates diverged in the postinitiation year, with the pregabalin cohort using more fibromyalgia-related inpatient care (3.2% versus 2.2%; P<0.05), any inpatient care (19.3% versus 16.8%; P<0.05), and fibromyalgia-related outpatient care (62.1% versus 51.8%; P<0.05). From the preinitiation period to the postinitiation period, the duloxetine cohort experienced decreases in certain utilization rates, whereas the pregabalin cohort had increases (percentage of patients with a fibromyalgia-relatedadmission, -1.2% versus 0.4% [P<0.01]; number of fibromyalgia-related outpatient claims, -1.7 versus 4.7 [P<0.01]). CONCLUSION: Fibromyalgia patients initiating pregabalin tended to consume more fibromyalgia-related inpatient and outpatient care in the first postinitiation year, whereas fibromyalgia patients initiating duloxetine tended to have lower utilization rates of fibromyalgia-related inpatient care in the postinitiation year than in the preinitiation year. KEYWORDS: duloxetine; fibromyalgia; health care utilization; pregabalin; propensity score methods PDF
La analgesia por melatonina se asocia con una mejoría del sistema descendente de modulación endógena del dolor en la fibromialgia.
Melatonin analgesia is associated with improvement of the descending endogenous pain-modulating system in fibromyalgia: a phase II, randomized, double-dummy, controlled trial. de Zanette SA, Vercelino R, Laste G, Rozisky JR, Schwertner A, Machado CB, Xavier F, de Souza IC, Deitos A, Torres IL, Caumo W1. BMC Pharmacol Toxicol. 2014 Jul 23;15:40. doi: 10.1186/2050-6511-15-40. PDF