Table 2 Relevant stress biomarker studies in AD

Bernardi et al. (2000) [42]

Serum levels of Cortisol and two neurosteroids, Allopregnanolone and dehydroepiandrosterone (DHEA), were compared in AD patients and controls

AD patients had significantly higher levels of cortisol and lower levels of Allopregnanolone compared to age matched controls

Clinical Dx of AD

N = 12

Popp et al. (2015) [34]

Longitudinal prospective study examining serum and CSF levels of cortisol and Aβ in age matched controls, patients with mild cognitive impairment (MCI), and AD patients.

CSF cortisol levels are elevated in subjects with AD and MCI. Elevated CSF cortisol levels were associated with faster cognitive decline in MCI of the AD type.

Clinical Dx of AD

Ennis et al. (2016) [35]

Prospective trial measuring once yearly a 24 h urinary cortisol level, over an average interval of 10.56 years

Elevated urinary cortisol level was related with a 1.31 times increase in AD risk, predicting increased AD risk an average of 6 years before onset.

Clinical Dx of AD. Participants that went on to be grouped in the “Future AD” group were 10 years older on average than control group