Background: Progressive brain atrophy in multiple sclerosis ( MS) may reflect neuroaxonal and myelin loss and MRI measures of brain tissue loss are used as outcome measures in MS treatment trials. This study investigated sample sizes required to demonstrate reduction of brain atrophy using three outcome measures in a parallel group, placebo-controlled trial for secondary progressive MS (SPMS). Methods: Data were taken from a cohort of 43 patients with SPMS who had been followed up with 6-monthly T1-weighted MRI for up to 3 years within the placebo arm of a therapeutic trial. Central cerebral volumes (CCVs) were measured using a semiautomated segmentation approach, and brain volume normalized for skull size (NBV) was measured using automated segmentation (SIENAX). Change in CCV and NBV was measured by subtraction of baseline from serial CCV and SIENAX images; in addition, percentage brain volume change relative to baseline was measured directly using a registration-based method (SIENA). Sample sizes for given treatment effects and power were calculated for standard analyses using parameters estimated from the sample. Results: For a 2-year trial duration, minimum sample sizes per arm required to detect a 50% treatment effect at 80% power were 32 for SIENA, 69 for CCV, and 273 for SIENAX. Two-year minimum sample sizes were smaller than 1-year by 71% for SIENAX, 55% for CCV, and 44% for SIENA. Conclusion: SIENA and central cerebral volume are feasible outcome measures for inclusion in placebo-controlled trials in secondary progressive multiple sclerosis. Neurology (R) 2009; 72:595-601

Sample sizes for brain atrophy outcomes in trials for secondary progressive multiple sclerosis / D. R., Altmann; B., Jasperse; F., Barkhof; K., Beckmann; M., Filippi; L. D., Kappos; P., Molyneux; C. H., Polman; Pozzilli, Carlo; A. J., Thompson; K., Wagner; T. A., Yousry; D. H., Miller. - In: NEUROLOGY. - ISSN 0028-3878. - 72:7(2009), pp. 595-601. [10.1212/01.wnl.0000335765.55346.fc]

Sample sizes for brain atrophy outcomes in trials for secondary progressive multiple sclerosis

POZZILLI, Carlo;
2009

Abstract

Background: Progressive brain atrophy in multiple sclerosis ( MS) may reflect neuroaxonal and myelin loss and MRI measures of brain tissue loss are used as outcome measures in MS treatment trials. This study investigated sample sizes required to demonstrate reduction of brain atrophy using three outcome measures in a parallel group, placebo-controlled trial for secondary progressive MS (SPMS). Methods: Data were taken from a cohort of 43 patients with SPMS who had been followed up with 6-monthly T1-weighted MRI for up to 3 years within the placebo arm of a therapeutic trial. Central cerebral volumes (CCVs) were measured using a semiautomated segmentation approach, and brain volume normalized for skull size (NBV) was measured using automated segmentation (SIENAX). Change in CCV and NBV was measured by subtraction of baseline from serial CCV and SIENAX images; in addition, percentage brain volume change relative to baseline was measured directly using a registration-based method (SIENA). Sample sizes for given treatment effects and power were calculated for standard analyses using parameters estimated from the sample. Results: For a 2-year trial duration, minimum sample sizes per arm required to detect a 50% treatment effect at 80% power were 32 for SIENA, 69 for CCV, and 273 for SIENAX. Two-year minimum sample sizes were smaller than 1-year by 71% for SIENAX, 55% for CCV, and 44% for SIENA. Conclusion: SIENA and central cerebral volume are feasible outcome measures for inclusion in placebo-controlled trials in secondary progressive multiple sclerosis. Neurology (R) 2009; 72:595-601
2009
01 Pubblicazione su rivista::01a Articolo in rivista
Sample sizes for brain atrophy outcomes in trials for secondary progressive multiple sclerosis / D. R., Altmann; B., Jasperse; F., Barkhof; K., Beckmann; M., Filippi; L. D., Kappos; P., Molyneux; C. H., Polman; Pozzilli, Carlo; A. J., Thompson; K., Wagner; T. A., Yousry; D. H., Miller. - In: NEUROLOGY. - ISSN 0028-3878. - 72:7(2009), pp. 595-601. [10.1212/01.wnl.0000335765.55346.fc]
File allegati a questo prodotto
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11573/42011
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? 43
  • Scopus 80
  • ???jsp.display-item.citation.isi??? 73
social impact