The effect of fibromyalgia and widespread pain on the clinically significant temporomandibular muscle and joint pain disorders--a prospective 18-month cohort study.

UNLABELLED: Although most cases of temporomandibular muscle and joint disorders (TMJD) are mild and self-limiting, about 10% of TMJD patients develop severe disorders associated with chronic pain and disability. It has been suggested that fibromyalgia and widespread pain play a significant role in TMJD chronicity. This paper assessed the effects of fibromyalgia and widespread pain on clinically significant TMJD pain (GCPS II-IV). Four hundred eighty-five participants recruited from the Minneapolis/St. Paul area through media advertisements and local dentists received examinations and completed the Graded Chronic Pain Scale (GCPS) at baseline and at 18 months. Baseline widespread pain (OR: 2.53, P = .04) and depression (OR: 5.30, P = .005) were associated with onset of clinically significant pain (GCPS II-IV) within 18 months after baseline. The risk associated with baseline fibromyalgia was moderate, but not significant (OR: 2.74, P = .09). Persistence of clinically significant pain was related to fibromyalgia (OR: 2.48, P = .02) and depression (OR: 2.48, P = .02). These results indicate that these centrally generated pain conditions play a role in the onset and persistence of clinically significant TMJD. PERSPECTIVE: Fibromyalgia and widespread pain should receive important consideration when evaluating and developing a treatment plan for patients with TMJD.

Interactions between multiple genetic determinants in the 5' UTR and VP1 capsid control pathogenesis of chronic post-viral myopathy caused by coxsackievirus B1.

Mice infected with coxsackievirus B1 Tucson (CVB1(T)) develop chronic, post-viral myopathy (PVM) with clinical manifestations of hind limb muscle weakness and myositis. The objective of the current study was to establish the genetic basis of myopathogenicity in CVB1(T). Using a reverse genetics approach, full attenuation of PVM could only be achieved by simultaneously mutating four sites located at C706U in the 5' untranslated region (5' UTR) and at Y87F, V136A, and T276A in the VP1 capsid. Engineering these four myopathic determinants into an amyopathic CVB1(T) variant restored the ability to cause PVM. Moreover, these same four determinants controlled PVM expression in a second strain of mice, indicating that the underlying mechanism is operational in mice of different genetic backgrounds. Modeling studies predict that C706U alters both local and long range pairing in the 5' UTR, and that VP1 determinants are located on the capsid surface. However, these differences did not affect viral titers, temperature stability, pH stability, or the antibody response to virus. These studies demonstrate that PVM develops from a complex interplay between viral determinants in the 5' UTR and VP1 capsid and have uncovered intriguing similarities between genetic determinants that cause PVM and those involved in pathogenesis of other enteroviruses.

Treatment of patients with osteoarthritis with rofecoxib compared with nabumetone.

BACKGROUND: Rofecoxib and nabumetone were developed to provide gastrointestinal benefits over traditional nonsteroidal antiinflammatory drugs (NSAIDs). However, there is limited comparative information relating to these 2 drugs. OBJECTIVE: The objective of this study was to compare rofecoxib and nabumetone, at their lower, recommended doses, in patients with osteoarthritis (OA). METHODS: Nine hundred seventy-eight patients with knee OA and a positive history of NSAID response were randomized to 12.5 mg rofecoxib per day (N=390), nabumetone 500 mg twice a day (N=392), or placebo (N=196) for 6 weeks. The primary efficacy end point was percent of patients with a "good" or "excellent" Patient Global Assessment of Response to Therapy (PGART) at week 6; PGART was also evaluated over days 1 to 6. Additional end points included investigator assessment of response, pain walking over 6 days and 6 weeks, joint tenderness, discontinuation as a result of lack of efficacy, and quality of life. Adverse experiences (AEs) were collected. RESULTS: Significantly more rofecoxib (50.4%) than nabumetone (43.3%, P=0.043) or placebo (29.5%, P<0.001) patients had a good or excellent PGART at week 6. Median time to a good or excellent PGART was significantly shorter with rofecoxib (52 hours) than nabumetone (100 hours, P=0.001) or placebo (>124 hours, P<0.001). Results for rofecoxib and nabumetone were similar in all additional end points except pain in walking over 6 days and 6 weeks, in both of which the rofecoxib treatment group demonstrated better results. There were significantly (P<0.050) more overall and serious AEs and discontinuations resulting from AEs with rofecoxib than nabumetone. Five rofecoxib and one nabumetone patients had confirmed thrombotic cardiovascular events (P=0.123). Information on thrombotic cardiovascular events from this study was included in a published, prespecified pooled analysis and is included here for completeness. CONCLUSIONS: At their recommended starting doses for OA, both agents were more effective than placebo. Rofecoxib at a dosage of 12.5 mg demonstrated significantly better efficacy in PGART than 1000 mg nabumetone in these patients known to be NSAID responders. Significantly more AEs occurred with rofecoxib than nabumetone. Considering these data and other recent safety information regarding cyclooxygenase-2 selective and nonselective NSAIDS, physicians must make risk/benefit assessments for each individual patient when considering the use of these agents, as recommended by the U.S. Food and Drug Administration.

Multiple viral determinants mediate myopathogenicity in coxsackievirus B1-induced chronic inflammatory myopathy.

Mice infected with myopathic coxsackievirus B1 Tucson (CVB1(T)) develop chronic inflammatory myopathy (CIM) consisting of hind limb weakness and inflammation. Amyopathic virus variants are infectious but attenuated for CIM. In this report, viral clones, chimeras, and sequencing were used to identify viral determinants of CIM. Chimeras identified several regions involved in CIM and localized a weakness determinant to nucleotides 2493 to 3200 of VP1. Sequencing of multiple clones and viruses identified five candidate determinants that were strictly conserved in myopathic viruses with one located in the 5' untranslated region (UTR), three in the VP1 capsid, and one in the 3C protease. Taken together, these studies implicate Tyr-87 and/or Val-136 as candidate determinants of weakness. They also indicate that there are at least two determinants of inflammation and one additional determinant of weakness encoded by myopathic CVB1(T).

Coxsackievirus B1-induced chronic inflammatory myopathy: differences in induction of autoantibodies to muscle and nuclear antigens by cloned myopathic and amyopathic viruses.

Infection of susceptible strains of mice with the myopathic Tucson strain of coxsackievirus B1 (CVB1(T)) leads to the development of chronic inflammatory myopathy (CIM). The underlying mechanism of CIM appears to be immunopathic, but it is not known whether autoimmunity is involved. The objectives of this study were to determine whether autoantibodies are produced and whether they correlate with the pathology of CIM. Mice were infected with either a myopathic (MP1.23 or MP1.24) or an amyopathic (AMP2.17) CVB1(T) cloned virus. The two myopathic (MP) viruses cause CIM, whereas the amyopathic (AMP) virus, derived from a variant of the same parent, causes the same acute disease but does not cause CIM. Antimuscle IgG was found in 51% of MP1.23-infected and 58% of MP1.24-infected mice but in just 18% of mice infected with AMP2.17 and in 10% of controls (MP vs AMP: chi(2), P < or =.006). Several staining patterns were observed, indicating that autoantibodies of multiple specificities were produced. Antinuclear antibodies were found in 57% of MP1.23-infected and 27% of MP1.24-infected mice but were rare in mice infected with AMP2.17 (0%) or in controls (4%) (MP vs AMP: chi(2), P < or =.01). Antiviral-antibody titers were higher with MP virus than with AMP virus (ANOVA, P <.001). A trend toward an association between antiviral antibody or autoantibodies and the presence or severity of clinical measures of CIM was noted but was not significant. These data suggest that the autoantibodies do not mediate muscle disease but are an independent manifestation of an immunopathic response induced by infection with MP but not AMP CVB1(T).