Fatigue heralding multiple sclerosis

BACKGROUND: Fatigue is a common symptom in multiple sclerosis (MS) and is an important determinant of overall well-being and disability. OBJECTIVE: To assess the frequency with which fatigue precedes the diagnosis of MS using a retrospective database analysis. METHODS: Between January 1, 2003 and September 30, 2008, patients diagnosed with fatigue with and without fatigue-related medications within a 3-year period prior to newly diagnosed MS were identified from the MarketScan Databases. All statistical analysis was performed using SAS. RESULTS: Of the 16,976 patients with MS in the overall population, 5305 (31.3%) were newly diagnosed with MS and had three years of continuous healthcare coverage prior to MS diagnosis. Of these patients, 1534 (28.9%) were labeled with chronic fatigue syndrome (ICD9-780.71) or malaise or fatigue (ICD9-780.79) prior to the diagnosis of MS. One-third of these patients were labeled with fatigue one to two years before the diagnosis; 30.8% were diagnosed only with fatigue and had no other MS symptoms prior to their MS diagnosis. Among the patients diagnosed with fatigue, 10.4% were also prescribed medication for fatigue. CONCLUSION: This study demonstrates that fatigue may herald MS, often by years. A careful history for transient neurological symptoms and a physical examination is warranted in any patient presenting with fatigue.