The paper forecasts the global burden of Alzheimer’s disease by 2050 using a stochastic multi-state model that incorporates worldwide population projections and epidemiological data on disease risk. In 2006, the global prevalence of Alzheimer’s disease was 26.6 million, and it is projected to quadruple to 106.8 million by 2050, with 1 in 85 people living with the disease. About 43% of prevalent cases require high-level care, equivalent to that of a nursing home. If interventions could delay both disease onset and progression by one year, there would be nearly 9.2 million fewer cases in 2050, with most of the decline attributed to fewer cases needing high-level care. The study evaluates the potential impact of interventions that delay disease onset or progression. The model accounts for disease severity, which is crucial for assessing the global burden, as care needs differ between early and late stages. The model uses transition probabilities between states, including incidence, progression, and death rates, which are influenced by age, calendar year, and potential interventions. The study also considers the effect of background mortality rates and the sensitivity of results to various assumptions. The results show that the global prevalence of Alzheimer’s disease will increase significantly due to population aging. The study highlights the importance of interventions that delay disease onset and progression, as even modest delays can significantly reduce the global burden. The paper also discusses the limitations of current data, including geographic variations in incidence rates and the need for more studies in developing countries. The authors conclude that the global burden of Alzheimer’s disease will quadruple by 2050, emphasizing the need for effective interventions to mitigate the impact of the disease. The study provides a framework for future research and policy-making to address the growing challenge of Alzheimer’s disease.The paper forecasts the global burden of Alzheimer’s disease by 2050 using a stochastic multi-state model that incorporates worldwide population projections and epidemiological data on disease risk. In 2006, the global prevalence of Alzheimer’s disease was 26.6 million, and it is projected to quadruple to 106.8 million by 2050, with 1 in 85 people living with the disease. About 43% of prevalent cases require high-level care, equivalent to that of a nursing home. If interventions could delay both disease onset and progression by one year, there would be nearly 9.2 million fewer cases in 2050, with most of the decline attributed to fewer cases needing high-level care. The study evaluates the potential impact of interventions that delay disease onset or progression. The model accounts for disease severity, which is crucial for assessing the global burden, as care needs differ between early and late stages. The model uses transition probabilities between states, including incidence, progression, and death rates, which are influenced by age, calendar year, and potential interventions. The study also considers the effect of background mortality rates and the sensitivity of results to various assumptions. The results show that the global prevalence of Alzheimer’s disease will increase significantly due to population aging. The study highlights the importance of interventions that delay disease onset and progression, as even modest delays can significantly reduce the global burden. The paper also discusses the limitations of current data, including geographic variations in incidence rates and the need for more studies in developing countries. The authors conclude that the global burden of Alzheimer’s disease will quadruple by 2050, emphasizing the need for effective interventions to mitigate the impact of the disease. The study provides a framework for future research and policy-making to address the growing challenge of Alzheimer’s disease.