title: Inclusion body myositis. Clinical features and clinical course of the disease in 64 patients.
abstract: The clinical features of inclusion body myositis (IBM) were of minor importance in the design of consensus diagnostic criteria, mainly because of controversial views on the specificity of signs and symptoms, although some authors reported "typical" signs. To re-assess the clinical spectrum of IBM, a single investigator using a standard protocol studied a cohort of 64 patients cross-sectionally. Symptom onset was before the age of 50 years in 20% of cases. Only a few patients (14 %) started with weakness other than that of quadriceps, finger flexor or pharyngeal muscles. The sequence of power loss was erratic, but onset of symptoms with quadriceps weakness predicted an earlier onset of dysphagia in older patients (> or = 56 years) compared with younger ones (< 56 years) (p = 0.02). Despite widespread weakness patients had favourable scores on three commonly used function scales and they kept their employment. Complete wheel-chair dependency was rare (3 %). A dominant characteristic was the anatomical distribution of afflicted muscles: ventral extremity muscle groups were more affected than dorsal muscle groups and girdle muscles were least affected, the latter preserving postural stability. Ankylosis, especially in extension of the fingers,was frequently present. Together with the sparing of intrinsic hand muscles it was helpful in the preservation of many skillful movements. IBM has a unique distribution of muscle weakness. Ankylotic contractures are common. We feel that their joint impact on daily functioning is characteristic for the disease.
authors.affiliation: Dept. of Neurology, Leiden University Medical Centre, Leiden, The Netherlands. u.badrising@zhsdirksland.nl
authors.forename: Umesh A
authors.initials: UA
authors.lastname: Badrising
authors.forename: Marion L C
authors.initials: ML
authors.lastname: Maat-Schieman
authors.forename: Johannes C
authors.initials: JC
authors.lastname: van Houwelingen
authors.forename: Peter A
authors.initials: PA
authors.lastname: van Doorn
authors.forename: Sjoerd G
authors.initials: SG
authors.lastname: van Duinen
authors.forename: Baziel G M
authors.initials: BG
authors.lastname: van Engelen
authors.forename: Carin G
authors.initials: CG
authors.lastname: Faber
authors.forename: Jessica E
authors.initials: JE
authors.lastname: Hoogendijk
authors.forename: Aeiko E
authors.initials: AE
authors.lastname: de Jager
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Koehler
authors.forename: Marianne
authors.initials: M
authors.lastname: de Visser
authors.forename: Jan J G M
authors.initials: JJ
authors.lastname: Verschuuren
authors.forename: Axel R
authors.initials: AR
authors.lastname: Wintzen
mesh_terms: D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D003402:Creatine Kinase / Q000097:blood; D003430:Cross-Sectional Studies; D003680:Deglutition Disorders / Q000209:etiology; D018450:Disease Progression; D004576:Electromyography / Q000379:methods; D004651:Employment; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018908:Muscle Weakness / Q000209:etiology; D018979:Myositis, Inclusion Body / Q000453:epidemiology / Q000378:metabolism / Q000503:physiopathology*; D009460:Neurologic Examination / Q000379:methods; D012189:Retrospective Studies; D012737:Sex Factors; D016138:Walking
chemical_list: D003402:Creatine Kinase