Results lend support to the employment of CSF matrix metalloproteinase 10 as a prognostic marker for dementia of the Alzheimer type as well as its inclusion to the [A/T/(N)] scheme to include pathologic aspects beyond amyloid and tau. CSF level of matrix metalloproteinase 10 could reflect ageing and neuroinflammation.

• From three independent memory clinic longitudinal studies (Spanish ACE, n = 410; German DCN, n = 93; German Mannheim, n = 53), CSF samples were obtained from 556 subjective cognitive decline and mild cognitive impairment patients and were analyzed for the levels of 184 proteins, to investigate CSF proteins linked with disease progression along with the clinical disease staging.

• A higher likelihood of progressing to dementia of the Alzheimer type and a faster cognitive decline were observed in mild cognitive impairment cases with elevated CSF level of matrix metalloproteinase 10.

• Prediction accuracy of CSF Aβ ₄₂ , P-tau ¹⁸¹ , and T-tau for conversion to dementia of the Alzheimer type was shown to be increased by CSF matrix metalloproteinase 10.

• Due to matrix metalloproteinase 10 incorporation to the [A/T/(N)] scheme, a considerable improvement in the prognostic value was seen in mild cognitive impairment patients with abnormal Aβ ₄₂ , but normal P-tau ¹⁸¹ and T-tau, and in mild cognitive impairment patients with abnormal Aβ ₄₂ , P-tau ¹⁸¹ , and T-tau.

• Matrix metalloproteinase 10 showed correlation with age in individuals with normal Aβ ₄₂ , P-tau ¹⁸¹ , and T-tau levels.