Modeling Patterns of Sex-Dependent Neuroprotection Loss in Alzheimer’s Disease

Alzheimer’s disease (AD) is a degenerative disorder of the cerebral neuro-glial-vascular units that affects older adults. Clinical observations suggest that postmenopausal females are at higher risk of getting AD than males and females with AD experience a faster progression of the disease than aged-matched male patients. Presently, AD is incurable. Mathematical models of AD can highlight mechanisms of AD onset and progression, and, thus, inspire improved therapies. In a recent paper (Drapaca in Fractal Fract 6:457, 2022) a population model of AD that accounts for sex differences was proposed. Variable fractional order temporal derivatives are used where the fractional order models the variable fading memory due to neuroprotection loss caused by AD progression and has different expressions for the two sexes. Since the above-mentioned paper is a purely theoretical proof-of-concept study, in this paper the sex-dependent neuroprotection losses are assumed to be proportional to the age-related declines in female estrogen and male testosterone estimated from clinical data. Numerical and semi-analytical solutions of the population model are given. Computer simulations show that the results agree with clinical observations.