Tuesday, September 6, 2011

Down syndrome and Alzheimer's

Dear Readers,
I would like to stray from our regular pattern of answering one of your emails or letters. The reason for this is a particular topic which many of you brought up during a recent lecture given by geriatrician Marina Blagodatny and psychiatrist Neil P. Dolan at the Trumbull Marriott.

The topic in question was dementia, specifically Alzheimer's dementia in people with Down syndrome. I hope that you do not mind my taking the opportunity to write about it some more.
Let's start with the definition of Down syndrome. It is a genetic disorder affecting one in 733 live births and accounts for about 15 percent of intellectual disabilitiy cases.

Symptoms of the learning problems associated with the syndrome range from mild to moderate, as does the patient's functional capacity. The cause of this disorder is, most of the time, an extra chromosome -- or genetic "building block" -- in our body. Chromosome 21 is the one affected. Normally a person has two copies of each of the chromosomes.

In at least 90 percent of Down syndrome cases, a person has three copies of Chromosome 21. This is not an illness one inherits from a parent, at least not in a majority of cases. The most commonly known risk factor is late maternal age. By age 45, a woman's risk of having a baby with this disorder is one in 35.

Life expectancy of patients with Down syndrome has increased dramatically in the last century. From roughly 10 years in the 1920s, it is now quite normal for those with Down syndrome to enjoy life way beyond age 50.

Unfortunately, there are many problems these patients and their families have to struggle with throughout their lives. People born with the syndrome age faster, and are prone to developing dementia.

It is known that 25 percent of Down syndrome patients have dementia by age 35. They are three to five more times more likely to get dementia as compared to patients the same age not born with the genetic disorder.

What is most perplexing is the fact that, although virtually all adult patients with Down syndrome have specific changes in the brain characteristic of dementia, not all of them have the symptoms.

For those of you who are more scientifically inclined, the changes are called neurofibrillary tangles and amyloid plaques, as well as loss of nerve cells in certain parts of the brain.

It must be clarified that people with other forms of intellectual disability not related to Down syndrome have the same risk and rate for dementia diagnosis as the non-affected population.

Scientists still do not fully understand why this is the case, other than that the Chromosome 21 abnormalities must play a significant role. Alzheimer's disease is the most common form of dementia. It is a progressive memory disorder that affects our ability to reason, remember, use language and think.

The disease can attack quickly and lead to demise in only a few years, or linger over 10 to 15 years, affecting not only the patient but the whole family. Approximately 4 million Americans are affected today by Alzheimer's. Presentation of the disease in patients with Down syndrome is quite different from that in other dementia patients.

Loss of language skills and the ability for self-care are quite common early. Seizures happen often in individuals who did not have them before. Incontinence, personality changes and sleep disruptions are also seen.

Since the mental abilities of patients with Down syndrome vary greatly to begin with, diagnosis of dementia is challenging. Unfortunately, the majority of patients are diagnosed late in the process of the illness. Standardized tests used in non-Down syndrome individuals do not apply to this group.

It is crucial for a specialist involved to have some idea of the person's cognitive baseline. Many advocate for the universal screening of Down syndrome individuals around age 30. There is a questionnaire called "The Dementia Questionnaire for Mentally Retarded Persons," which can help, as well as a few other available tools. As a rule, a specialized dementia center is the best place to follow a patient with Down syndrome and Alzheimer's. The input from the caregivers and the primary care physician are considered absolutely necessary for the proper diagnosis and the meaningful follow-up.

One of the important goals of early diagnosis is to rule out other reasons for cognitive decline and behavioral problems that can be potentially curable. Thyroid problems, excessive medication use, severe depression, and unrecognized hearing and vision problems may all present as similar or identical to Alzheimer's. Even simple infection can trick us.

The treatment of Alzheimer's dementia in Down syndrome patients is uncharted waters. Only one out of four drugs available has been tested in these patients, and no drug is specifically approved by the Food and Drug Administration. Trying them, however, may prove very beneficial, as they may help with behaviors and stabilize functional abilities.

Other medications, like antidepressants, mood stabilizers and anti-anxiety medications, may also play a role when used judiciously and closely supervised and monitored.

There is yet another reality of this particular scenario. Many primary caregivers of Down syndrome patients in their 40s and 50s can be their aging parents and/or siblings. Not only do they have to face their own fears about forgetfulness and their own memory lapses, they are often unable to meaningfully plan ahead.

Legal issues are important, as well as financial ones. There has to be a plan of care in case of a caregiver's illness or, as horrible as it is to think about, death.

I strongly recommend that all involved use their local Alzheimer's Association, as well as local Down syndrome support groups and the National Down Syndrome Society. The help of local religious organizations also can be priceless. Government support is available, albeit limited. All of us professionals involved in diagnosis and treatment of dementia are more than willing to help.

Dr. Beata Skudlarska is a Bridgeport geriatrician. Send questions to Bridgeport Hospital Center for Geriatrics, 95 Armory Road, Stratford CT 06614 or geriatricmd@aol.com.

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