The prevalence of diabetes mellitus (DM) continues to increase because of sedentary life style and inappropriate
diet. DM is one of the most common metabolic diseases, affecting more than 240 million people worldwide. It is projected
that the number of people with DM will continue to increase in the next decade. Alzheimer disease (AD) is the
most common cause of dementia, and affects over 24 million people globally, mostly senior citizens. The worldwide
prevalence of AD is estimated to double in the next 20 years.
How are these two chronic and debilitating diseases similar? Do they have common denominators? AD is similar to DM
in many ways, in that both are associated with defective insulin release and/or signalling, impaired glucose uptake, amyloidosis,
increased oxidative stress, stimulation of the apoptotic pathway, angiopathy, abnormal lipid peroxidation, ageing
(in type 2 DM), brain atrophy, increased formation of advanced glycation end products and tau phosphorylation, impaired
lipid metabolism and mitochondrial pathology. The pathogenesis of both AD and DM has genetic as well as environmental
components. Both can also cause impaired cognition and dementia. All of these common denominators indicate
that AD and DM share a lot of factors in terms of pathophysiology, histopathology and clinical outcome. These similarities
can be used in the search for and design of effective pharmacotherapy for AD, since potent therapeutic agents such as
insulin, incretins, oral hypoglycaemic agents and antioxidants used in the management of DM may play a key role in the
treatment of patients with AD.