Aging and Life Expectancy

Today, people with Down syndrome (DS) are living longer and healthier than any other time in the past. In 1900, the life expectancy of people with DS was 9 years. By 1984, the life expectancy had increased to 28 years. Since then, the life expectancy of people with DS has increased to about 60 years* (1-4). 

While there are some racial differences in life expectancy, the differences appear to be decreasing. In 1950, the life expectancy of non-Hispanic Blacks was 22 years (mean) and 2 years (median). The life expectancy of non-Hispanic whites was 26 years (mean) and 4 years (median). In 2010, the life expectancy of non-Hispanic Blacks was 50 (mean) and 57 (median). The life expectancy of non-Hispanic whites was 54 (mean) and 58 (median) (5). 

We had the privilege to meet one of the oldest well-documented people with DS, an elderly woman with DS. She died from the complications of a fractured hip – much of which had to do with being 83 years old and a woman (although osteoporosis is thought to be more common in people with DS). While living into the 70s is still not common for people with DS, there are more reports of individuals with DS living that long (6-8)

There are premature aging issues in people with DS. As a rough guide, people with Down syndrome often seem to be younger physically than their chronological age until about age 35. They may look younger and are less likely to have some health conditions sometimes seen in people without DS as they get into their late 20s and early 30s (such as high blood pressure). However, after age 35, many people with DS seem to age more rapidly. As the years go by beyond 35, we often begin to think of individuals as older than their chronological age when it comes to physical health and medical problems. While there are still some conditions, like high blood pressure, solid tumors, and atherosclerosis, that people with DS get less frequently, this is not the case for all conditions as people with DS age. Alzheimer's disease is one condition that occurs earlier and more frequently in people with DS. On average, it occurs 20 (or more) years earlier in people with DS than those without DS.

Additionally, we consider the rate of aging to increase with time. At 40, we might consider a person with DS to be physically 5 years older and by 60 or 65 to be perhaps 20 years older than a person without DS. That certainly varies from person to person in that aging seems to occur at different rates depending on the individual. Other health problems can contribute to varying rates of aging. This is true for adults with DS and without DS.

While the life expectancy of people with DS has increased dramatically as noted above, it does seem to be leveling off. Alzheimer's disease seems to be the biggest factor that is preventing the continued increase in life expectancy (9). When the ongoing research finds successful treatments for Alzheimer's disease for people with DS, it is hoped and anticipated that the life expectancy of people with DS will start to increase again. 

While we don't have the answer to stopping or reversing aging, there are many things we can do to improve or optimize our health as we age. Participating in regular exercise, eating a healthy diet, maintaining a healthy weight, keeping our minds stimulated, engaging in social opportunities, and optimizing our vision and hearing all likely have a positive effect on our health as we age. 

*There are a range of statistics that are used to estimate and predict the age at which an individual will die. It is important to note that these numbers are averages. Life expectancy predicts how many years an individual born in a particular year will live. Life expectancy is different from mean age of death, which is an average of the ages at which a group of people died in a particular year. 

More resources on aging and Alzheimer's disease

References

1. Glasson EJ, Sullivan SG, Hussain R, Petterson BA, Montgomery PD, Bittles AH. The changing survival profile of people with Down's syndrome: Implications for genetic counselling . Clin Genet. 2002;62(5):390-393. doi:10.1034/j.1399-0004.2002.620506.x

2. Bittles AH, Glasson EJ. Clinical, social, and ethical implications of changing life expectancy in Down syndrome . Dev Med Child Neurol. 2004;46(4):282-286. doi:10.1111/j.1469-8749.2004.tb00483.x

3. Coppus AM, Evenhuis HM, Verberne GJ, et al. Survival in elderly persons with Down syndrome . J Am Geriatr Soc. 2008;56(12):2311-2316. doi:10.1111/j.1532-5415.2008.01999.x

4. Zhu JL, Hasle H, Correa A, et al. Survival among people with Down syndrome: A nationwide population-based study in Denmark . Genet Med. 2013;15(1):64-69. doi:10.1038/gim.2012.93 

5. de Graaf G, Buckley F, & Skotko BG. Estimation of the number of people with Down syndrome in the United States. Genet Med. 2017;19(4):439-477. doi: 10.1038/gim.2016.127

6. "Woman with Down syndrome defies odds to celebrate her 75th birthday"  - Today 

7. "Britain's oldest person with Down's syndrome who wasn't expected to live beyond 10 celebrates 78th birthday"  - Nottingham Post 

8. "La Crosse woman with Down syndrome celebrates 75th birthday, defying the odds"  - LaCrosse Tribune

9. Iulita M, Chavez D, Christensen M, et al. Association of Alzheimer's disease with life expectancy in people with Down syndrome . JAMA Netw Open. 2022;5(5);e2212910. doi: 10.1001/jamanetworkopen.2022.12910