COVID-19 in 2020 and 2021. See the box “The Effect of the COVID-19 Pandemic on Deaths from Alzheimer’s Disease” for a discussion of the dramatic effect of the pandemic on Alzheimer’s mortality. In this section, “deaths from Alzheimer’s disease” refers to what is officially reported on death certificates. It is difficult to determine how many deaths are caused by Alzheimer’s disease each year because of the way causes of death are recorded. According to data from the CDC, 121,499 people died from Alzheimer’s disease in 2019, the latest year for which data are available.360 The CDC considers a person to have died from Alzheimer’s if the death certificate lists Alzheimer’s as the underlying cause of death, defined as “the disease or injury which initiated the train of events leading directly to death.”362 Note that while death certificates use the term “Alzheimer’s disease”, the determination is made based on clinical symptoms in almost every case, and thus more closely aligns with “Alzheimer’s dementia” as we have defined it in previous sections of this report; to remain consistent with the CDC terminology for causes of death, we use the terms “Alzheimer’s disease” for this section. The number of deaths from dementia of any type is much higher than the number of reported Alzheimer’s deaths. In 2019, some form of dementia was the officially recorded underlying cause of death for 271,872 individuals (this includes the 121,499 from Alzheimer’s disease).360,363 Therefore, the number of deaths from all causes of dementia, even as listed on death certificates, is more than twice as high as the number of reported Alzheimer’s deaths alone. Severe dementia frequently causes complications such as immobility, swallowing disorders and malnutrition that significantly increase the risk of serious acute conditions that can cause death. One such condition is pneumonia (infection of the lungs), which is the most commonly identified immediate cause of death among older adults with Alzheimer’s or other dementias.364-367 One preCOVID-19 autopsy study found that respiratory system diseases were the immediate cause of death in more than half of people with Alzheimer’s dementia, followed by circulatory system disease in about a quarter.365 Death certificates for individuals with Alzheimer’s often list acute conditions such as pneumonia as the primary cause of death rather than Alzheimer’s.365-366 As a result, people with Alzheimer’s dementia who die due to these acute conditions may not be counted among the number of people who die from Alzheimer’s disease, even though Alzheimer’s disease may well have caused the acute condition listed on the death certificate. This difficulty in using death certificates to determine the number of deaths from Alzheimer’s and other dementias has been referred to as a “blurred distinction between death with dementia and death from dementia.”368 Another way to determine the number of deaths from Alzheimer’s dementia is through calculations that compare the estimated risk of death in those who have Alzheimer’s dementia with the estimated risk of death in those who do not have Alzheimer’s dementia. A study using data from the Rush Memory and Aging Project and the Religious Orders Study estimated that 500,000 deaths among people age 75 and older in the United States in 2010 could be attributed to Alzheimer’s dementia (estimates for people 30 Alzheimer’s Association. 2022 Alzheimer’s Disease Facts and Figures. Alzheimers Dement 2022;18. Mortality and Morbidity 31 The Effect of the COVID-19 Pandemic on Deaths from Alzheimer’s Disease In 2020, COVID-19 was the third leading cause of death in the United States, pushing Alzheimer’s disease from the sixth to the seventh leading cause of death, even though the total number of deaths from Alzheimer’s disease recorded on death certificates increased 10.5% between 2019 and 2020 to 134,242.360 COVID-19 was likely a significant contributor to the large increase in deaths from Alzheimer’s. Data from the Centers for Disease Control and Prevention show that excess mortality (the difference between the observed number of deaths and the expected number of deaths during a given period) from any cause has been very high since the start of the pandemic, especially among older adults.373 Many of these excess deaths were in vulnerable older adults with Alzheimer’s disease and other dementias (Figure 6). Compared with the average of the five years before 2020, there were 15,925 more deaths from Alzheimer’s disease and 44,729 more deaths from all dementias, including Alzheimer’s, in 2020. This is, respectively, 13% and 17% more than expected.360 Preliminary reports from 2021 show at least 11,000 more deaths from Alzheimer’s and other dementias compared with the average of the five years before 2020.374 While the number of people dying from Alzheimer’s has been increasing over the last two decades, the number of excess deaths from Alzheimer’s disease far exceeded what would be expected from the normal trend line. The lower number of excess deaths in 2021 compared with 2020 may, in part, be attributable to fewer deaths due to COVID-19 being incorrectly recorded as deaths due to dementia. It could also be the result of vaccinations. Older adults have the highest rate of