Cerebral Multimorbidity in Aging

The aging brain is characterized by the simultaneous presence of multiple pathologies, and the prevalence of multi-morbidity increases with age. Large clinico-pathological correlative studies have shown that in brains of both cognitively intact and impaired aged subjects, the presence of a single disease is a rare finding, while most brains show neurodegenerative, cerebrovascular and other pathologies, which frequently have been missed clinically and may even be difficult to identify at postmortem examination. Since both clinical and autopsy studies differ in selection and classification criteria and in the applied evaluation methods, irrespective of the clinical symptoms, the reported frequency of cerebral pathologies varies considerably. The frequent co-occurrence of different pathologies indicates their mutual interaction in order to promote cognitive decline and other clinical symptoms. These facts have also implications for improvement of clinical diagnosis and prognosis, for the development of specific biomarkers, preventive strategies, and therapeutic targets for cerebral multi-morbidity.