Severe Impairment Battery effective for Alzheimer's disease

Findings presented at the American Academy of Neurology showed accuracy of quantitatively-derived Severe Impairment Battery composite scores for individuals with moderate-to-severe or severe Alzheimer’s disease.

“While the [Severe Impairment Battery (SIB)] detects treatment effects in patients with moderate-to-severe [Alzheimer’s disease] who perform at floor level on other cognitive scales, traditional total SIB scoring may lack sensitivity in severe [Alzheimer’s disease],” Alireza Atri, MD, PhD, of Brigham and Women’s Hospital and Harvard Medical School, and colleagues wrote.

To assess accuracy of a composite score of SIB items for detection of treatment effects in individuals with severe Alzheimer’s disease, researchers developed a quantitative SIB composite score and a severe SIB composite score using partial least squares regressions tested in separate datasets. The training dataset (n = 966) was pooled from three 24-week phase 3 memantine trials in individuals with moderate-to-severe Alzheimer’s disease.

SIB total score detected significant treatment effects of memantine among all study participants, compared with placebo (P < .05).

Quantitative SIB composite scores did not improve sensitivity, according to researchers.

The quantitative severe SIB composite score included five items, language, memory, praxis, attention, and orientation, with weights of 0.009; 0.003; 0.021; 0.02; and 0.044, respectively.

Quantitative severe SIB composite scores improved sensitivity among participants with severe Alzheimer’s disease at weeks 8, 12, 18 and 24.

“In severe Alzheimer’s disease patients, [quantitative severe SIB composite scores] provided additional measurement sensitivity and differentiations between memantine and placebo-treated vs. total SIB score,” the researchers wrote. “The [quantitative SIB composite score] did not improve sensitivity, indicating that SIB total score is optimized for combined moderate-to-severe patients. Development and utilization of quantitatively optimized composite scales from established clinical trial measures may improve scale sensitivity in patient subgroups, particularly when floor effects are present.” – by Amanda Oldt

Reference:

Atri A, et al. Improved detection of treatment effects in severe Alzheimer’s disease: A quantitatively-derived SIB-based composite scale. Presented at: American Academy of Neurology Annual Meeting; April 22-28, 2017; Boston.

Disclosure: The study was supported by Allergan.