As life expectancy in the United States has increased, the number of elderly people in the population has also increased. These increases have led seniors (people aged 90 and older) to become the fastest-growing age group in the country. Older adults face many unique challenges due to their age, one of which is disability. Disability in the elderly has a strong impact on society 1 and will continue to constitute a growing burden in the years to come. Although many studies show that disability rates are decreasing in the United States2, the rapid expansion of the older age group continues to pose health challenges for future generations. Disability prevalence rates are very high among the elderly3 and even reach 97% among centenarians4. These high rates of disability will have a huge financial impact in the future as people living with disabilities have much higher healthcare expenses5. Because of the growing concern associated with disability in older adults, many researchers have examined factors that may be associated with disability risk in older adults. These factors vary widely, including functional limitations6-9, physical activity level10, 11, depression12-15, cognitive status13, 16, 17, comorbidities18, 19, falls6, 20, self-rated health21, 22, social interaction23, and others24. Understanding the incidence of disability in older adults is a critical step in identifying methods to reduce disability in this at-risk age group. We examined incident disability in a large cohort of participants aged 90 years and older, The 90+ Study. As part of their participation in The 90+ Study, participants are followed longitudinally, with detailed information on functional abilities obtained you...... half of the paper ...... estimate disability, especially in older adults47. This manuscript details the alarming increase in disability among older adults. With the rapid growth of this age group, problems associated with functional loss have a huge financial impact worldwide. The study identified several risk factors associated with increased incidence of disability, many of which may be modifiable. This is especially critical, as CHF is the most costly medical disease in the United States, accounting for more than 5% of the total healthcare budget48. With the prevalence and incidence of CHF rapidly increasing in the United States49, it will be critical to prepare for the dramatic increase in disability that will result. Reducing risk factors for congestive heart failure, such as hypertension and high cholesterol, would likely be helpful in reducing disability in older adults.