Natural history of human T-lymphotropic virus 1-associated myelopathy: a 14-year follow-up study.
BACKGROUND
The progression of neurological disability in human T-lymphotropic virus 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) remains undefined.


OBJECTIVE
To determine the time course of disability scores and to identify predictors of outcome among patients with HAM/TSP.


METHODS
Clinical 14-year follow-up study.


METHODS
University hospital. Patients One hundred twenty-three patients with HAM/TSP.


METHODS
We determined time from onset to the following 4 Kurtzke Disability Status Scale (DSS) end points: scores of 6 (unilateral aid required), 6.5 (bilateral aid required), 8 (wheelchair confinement), and 10 (death related to the disease). Times to reach selected DSS scores were estimated using the Kaplan-Meier method. Univariate and multivariate analyses identified variables related to the rate of progression to DSS 8. The HTLV-1 proviral loads were also assessed.


RESULTS
The disability of the cohort progressed throughout the follow-up period. The median times from onset to DSS 6, 6.5, and 8 were 6, 13, and 21 years, respectively. The median time from DSS 6 to DSS 8 was 8 years; DSS 10 was reached by one fourth of the patients within 20 years. Age at onset of 50 years or older and high HTLV-1 proviral load were associated with a shorter time to DSS 8 (P = .01 and P = .02, respectively). A shorter time to DSS 6 significantly adversely affected the time to progression from DSS 6 to DSS 8.


CONCLUSIONS
Human T-lymphotropic virus 1-associated myelopathy/tropical spastic paraparesis is a rapidly disabling disease. Monitoring for HTLV-1 proviral load is recommended in future therapeutic trials.
Olindo
Stéphane
S
Department of Neurology, University Hospital of Fort de France, Fort de France, Martinique. stephane.olindo@chu-fortdefrance.fr
Cabre
Philippe
P
Lézin
Agnes
A
Merle
Harold
H
Saint-Vil
Martine
M
Signate
Aissatou
A
Bonnan
Mickael
M
Chalon
Aurelie
A
Magnani
Lionel
L
Cesaire
Raymond
R
Smadja
Didier
D
D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D004185:Disability Evaluation; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D015368:Human T-lymphotropic virus 1; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D015493:Paraparesis, Tropical Spastic / Q000175:diagnosis / Q000453:epidemiology* / Q000821:virology*; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012306:Risk; D012720:Severity of Illness Index; D013118:Spinal Cord Diseases / Q000175:diagnosis / Q000453:epidemiology* / Q000821:virology*; D013997:Time Factors