Amyloid load may impair self-esteem among those at risk for Alzheimer’s disease

Amyloid load appeared to negatively influence the progression of self-esteem among people at risk for Alzheimer’s dementia, according to study results published in Journal of Clinical Psychiatry.

“The relationship between amyloid load and depression has been well described in cross-sectional studies in dementia-free individuals; however, little is known about the links between amyloid load and depressive symptom changes over time in individuals at risk of [Alzheimer’s dementia],” Ismael Conejero, MD, PhD, of Nîmes University Hospital and University of Montpellier’s Institute of Functional Genomics, France, and colleagues wrote.

The researchers analyzed data from 262 participants aged 70 years or older from the French Multidomain Alzheimer Preventive Trial-AV45, which was conducted between May 30, 2008, and Feb. 24, 2011. Participants completed multiple neuropsychological tests and Geriatric Depression Scale (GDS)-15 items following one PET-AV45 scan, which was considered positive if the amyloid burden was pathologic. Researchers determined regional amyloid load using principal component analysis (PCA).

GDS PCA at enrollment and at 6, 12, 24 and 36 months evaluated four dimensions: life satisfaction, apathy, self-esteem and anxiety.

At enrollment, 11% of participants had GDS scores higher than five, and 34% had positive AV45. Three amyloid regional dimensions were responsible for 85.1% of total variation, with 65.8% attributed to frontal, parietal, temporal, precuneus and anterior and posterior cingulate cortices. The four GDS dimensions accounted for 48.9% of total variation.

Researchers observed significant increases at 36 months of total GDS score and apathy level. Self-esteem decreased significantly at 36 months (beta = 0.029; 95% CI, 0.052 to 0.007). Decrease in self-esteem was associated with global amyloid load, while change in total GDS score was not.

“This suggests that other factors might interfere with the global level of depressive symptoms in this population and need to be identified in order to propose specific personalized strategies to slow down cognitive decline,” Conejero and colleagues wrote.

Hippocampus and caudate nuclei amyloid loads were significantly associated with smaller self-esteem decreases at 36 months (M1 = 0.033; 95% CI, 0.007 to 0.059; and M2 = 0.031; 95% CI, 0.005 to 0.057).

Limitations included non-specific evaluation of the four GDS dimensions and low number of participants with depressive symptoms.

“Our results should be confirmed using specific clinical tools to evaluate these dimensions,” the researchers wrote. “The analysis of regional PET amyloid profiles may help to anticipate potential trajectories of depressive dimensions in non-demented individuals, and then to propose adapted preventive strategies.”