Alzheimer’s Disease: Epidemiology, Etiology, Risk Factors, and Future Predictions

Alzheimer’s disease (AD) remains a significant global health challenge, characterized by progressive cognitive decline and neurodegeneration. This review comprehensively examines the epidemiology, etiology, hypotheses, risk factors, current treatment modalities, and future predictions in AD management. AD presents in two main forms: familial or early-onset AD (FAD) and sporadic or late-onset AD (SAD). While FAD is linked to genetic mutations, SAD is multifactorial, involving genetic, environmental, and lifestyle factors. Various hypotheses, including the amyloid hypothesis, cholinergic deficit, impaired brain insulin signaling, oxidative stress, and neuroinflammation, contribute to our understanding of AD pathogenesis. Current treatment options primarily focus on symptomatic relief, including acetylcholinesterase inhibitors, N-methyl-D-aspartate receptor antagonists, and recently approved amyloid-directed monoclonal antibodies. However, emerging disease-modifying therapies (DMTs) targeting amyloid, tau, and neuroprotective pathways offer promise for slowing or halting disease progression. Additionally, innovative drug delivery systems, such as nanotechnology-based formulations and intranasal delivery, aim to enhance drug efficacy and brain targeting. Future diagnostics are crucial for early detection and intervention, utilizing molecular biomarkers and digital tools for precision medicine approaches. Ultimately, a multifaceted approach encompassing pharmacological, diagnostic, and personalized care strategies is essential for effective AD management and improving patient outcomes.