title: A longitudinal study of variations in and predictors of fatigue in multiple sclerosis.
abstract: OBJECTIVE
  To describe variations in fatigue over the course of 2 years in a sample of persons with multiple sclerosis (MS), and to investigate the predictive value of the following variables on variations in fatigue: sex, age, sense of coherence, living with a partner, living with children, work status, immunomodulatory treatment, mood, disease severity, disease course, time since diagnosis and time.
  
  
  METHODS
  Every 6 months, 219 outpatients at an MS specialist clinic were assessed using the Fatigue Severity Scale (FSS). Predictive values were explored with Generalised Estimating Equation employing proportional odds models; FSS scores were categorised as non-fatigue, borderline fatigue or fatigue.
  
  
  RESULTS
  FSS scores varied significantly (p = 0.02); 54% changed FSS category one or several times, 27% were persistently fatigued and 19% persistently non-fatigued. Independent predictors of increased fatigue were depressive symptoms, weak/moderate sense of coherence, living with a partner and not working. Furthermore, moderate disease severity predicted increase when combined with >10 years since diagnosis or a progressive course. Independent predictors of decreased fatigue were no depressive symptoms, strong sense of coherence, living alone and working. Moreover, mild and severe disease predicted a decrease when combined with >10 years since diagnosis, and mild severity combined with a progressive course.
  
  
  CONCLUSIONS
  Mood, sense of coherence and living with a partner were independent predictors of fatigue in persons with MS. In addition to monitoring disease related variables, health related services should apply a broad range of approaches and repeatedly assess fatigue in persons with MS, to provide preventive care and appropriate interventions.
authors.affiliation: Division of Neurology, Department of Clinical Neuroscience, Karolinska Institutet, Karolinska University Hospital, Huddinge, Stockholm, Sweden. sverker.johansson@ki.se
authors.forename: S
authors.initials: S
authors.lastname: Johansson
authors.forename: C
authors.initials: C
authors.lastname: Ytterberg
authors.forename: J
authors.initials: J
authors.lastname: Hillert
authors.forename: L
authors.initials: L
authors.lastname: Widén Holmqvist
authors.forename: L
authors.initials: L
authors.lastname: von Koch
mesh_terms: D000328:Adult; D000367:Age Factors; D003863:Depression / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology; D005221:Fatigue / Q000453:epidemiology* / Q000209:etiology; D005260:Female; D006801:Humans; D007389:Internal-External Control; D008137:Longitudinal Studies; D008297:Male; D017533:Marital Status; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D016017:Odds Ratio; D012307:Risk Factors; D012737:Sex Factors; D012803:Sick Role; D012931:Social Environment; D013223:Statistics as Topic; D014478:Unemployment / Q000706:statistics & numerical data