Life does not consist mainly, or even largely, of facts and happenings. It consists mainly of the storm of thought that is forever flowing through one’s head.
—MARK TWAIN
ALZHEIMER’S DISEASE CAUSES ONLY AROUND 65 PERCENT of the dementia cases recorded, but people tend to use the terms Alzheimer’s and dementia interchangeably. A friend of mine does this, referring to her mother’s Alzheimer’s, when it’s fairly clear, meeting the mother in question, that some other kind of dementia is to blame for her illness.
Senile dementia as a term was coined in 1838 by one Jean-Étienne Esquirol, a doctor who noted a progressive loss of memory and initiative and creeping emotional instability in people over the age of sixty-five. The phrase may have been new, but the syndrome was already as old as the hills. Plato was involved in a discussion about dementia in the fifth century B.C. Lucullus, a Roman general, died of dementia, and his decline, as written about by Plutarch, is persuasively of the Alzheimer’s kind. Marcus Aurelius, the Roman philosopher-emperor, writes in the second century A.D. that “even if a man lives a long time, it’s doubtful his mind will survive him.” He goes on to say that “the coming of senility may not be accompanied by respiratory or digestive disorders, no loss of the sensory life or of one’s desires, but even so, the power of the faculties, of knowing and doing your duty, dealing with crises, sensing that the time has come to die—all of the decisions, in short, that demand proper thinking about, all of these will nonetheless already be fading away.
“We must get on and live life,” he says, “not just because life is brief, but because our understanding may be briefer.” It’s an issue that has taxed individuals, their families, and the workings of society in all the years since. They worried about it in the fourteenth century: A test was discovered in the 1970s, an equivalent to the question-and-answer diagnostic test (MMSE) used today, that dated from 1383 and had been used to assess the competence of a woman in Cambridgeshire to run her own affairs. The 1970s were an important decade for dementia. It wasn’t until the end of the 1960s that it was realized just how prevalent Alzheimer’s is. Before that it was thought to be a rare disease, one small exotic branch of senility. Most cases were assumed to be of the vascular type, a furring up of brain arteries, which was still considered a normal part of aging. Alzheimer’s was listed in the textbooks as uncommon. It was only when autopsies began to be done on brains in huge numbers, and retrospective microscopic examination of stored brains was undertaken, that it became startlingly clear that Alzheimer’s was the main cause of dementia.
Dementia has been important in our history, then, and perhaps more important than is generally recognized. The tradition, or at least tendency, to elect men and women of mature years into power, and to allow people of over seventy to hang on to power, increases the risk that we will have leading statesmen and stateswomen—governors, presidents, and prime ministers—suffering from some form of dementia. It’s only fairly recently been discovered that Harold Wilson stepped down as prime minister in 1976 because he’d become aware of his own mild cognitive impairment (MCI), and foresaw accurately that dementia was on its way. Not all politicians have the insight to abdicate so early in the disease. It’s alleged that Woodrow Wilson had dementia in office, and that the resulting capriciousness of his decision making culminated in his failure to get Congress to approve the Versailles Treaty that ended World War I. It is also suggested that Stalin was a dementia sufferer, his failing intellect combining suggestively with increasing levels of aggression and paranoia. Roosevelt was evidently quite ill and possibly suffering symptoms of dementia when he had to negotiate with Stalin at Yalta in 1945 (he died two months later of a cerebral hemorrhage). The Labour prime minister Ramsay MacDonald is said to have struggled with dementia in office. Lenin died of dementia, which, as in the case of Stalin, was most likely brought on by syphilis. There seems little doubt that Urho Kekkonen, the president of Finland from 1956 to 1981, had Alzheimer’s while in office, a fact actively covered up from about 1978 onward. Ronald Reagan showed early signs of the disease during his presidency.
Dementia is fast becoming the condition that’s cited by the young and healthy as the disease that is most feared. It’s not curable, unlike cancer. It’s not able to be tackled with drastic measures, unlike heart disease and its bypasses and transplants. It’s more fundamental than that. We don’t have brains; we are our brains. You can lose a leg or an arm, or accept the gift of another person’s heart and lungs, and still be yourself. The brain is where the self lives. Lose the use of your brain by degrees and the self is stripped away, layer by layer. In the early stages, the middle stages, even in the early part of the late stage this may well be something you are conscious of, the lights going out one by one.
The dementia numbers are ascribed to our soaring life expectancy rates. It’s only an epidemic, so the orthodoxy goes, because we are living long enough to develop it. In 1910, when very little dementia was recorded, only 15 percent of people lived longer than the age of fifty. Life expectancy then was around forty-eight for men and fifty-two for women. We live, on average, around thirty years longer than we did a hundred years ago. Add to this another salient statistic: namely, the number of people over sixty-five worldwide is expected to double in the next twenty years. There’s the engine of the epidemic on a plate.
Vascular dementia, the artery-furring sort, is the second biggest dementia disease group by numbers of sufferers. Around 20 percent of dementia victims have this one, and another 20 percent may have a vascular/Alzheimer’s combination. It’s the dementia that’s most equivalent to heart disease. Vein damage prevents blood from getting to parts of the brain; neurons are starved and die. Vascular dementia can be caused by stroke: single-infarct dementia, if it’s a single serious stroke; multi-infarct dementia, if it’s lots of little strokes, some so tiny as barely to register symptoms, and this is the most common sort. A rare variant called Binswanger’s disease begins in blood vessels deep in the brain and may start to show itself with walking problems.
King Lear has been diagnosed, from the verbal evidence of the play, to have suffered from vascular dementia. There’s no doubt he suffered from one kind or another of dementing illness. “Methinks I should know you, and know this man,” he says in act 4. “Yet I am doubtful; for I am mainly ignorant / What place this is; and all the skill I have / Remembers not these garments; nor I know not / Where I did lodge last night. Do not laugh at me.”
The third most common sort is dementia with Lewy bodies (DLB); in fact, some studies claim it’s the second most common. Notoriously difficult to diagnose, it overlaps with other dementias. At least 20 percent of Americans with dementia are thought to have DLB, and among the elderly demented the percentage is much higher. Dr. Frederich Lewy identified this variant in 1912, having spotted tiny foreign bodies (proteins again) in the neurons in the brain. Parkinson’s disease also has these bodies, though in the case of Parkinson’s they’re confined to one brain area, the substantia nigra. Symptoms can mimic Alzheimer’s, though DLB victims may have more specific problems, with near-normal memory and language skills but trouble with abstract thinking. Hallucinations are so common as to be diagnostic, much more so than in Alzheimer’s. Sufferers may also have Parkinson’s-like symptoms, trouble with movement and tremors. It’s a very up-and-down disease with good days and bad days, good hours and bad hours.
The best known of the frontotemporal dementias is Pick’s disease, named after a Czech neurologist, Arnold Pick (1851–1924). Pick’s was isolated and named in 1892. Specks known as Pick’s bodies are found in the frontal and temporal lobes, to which this variant is confined. Pick’s can be nasty: It comes on early, can instigate massive personality change, and sufferers exhibit an unfortunate tendency toward lechery.
Frontotemporal dementia (FTD) also includes particular niche dementias, like aphasia dementia (loss of language) and semantic dementia, in which the connections between words and meanings are lost. Frontotemporal dementia sufferers have specific problems with language, behavior, and emotional response. In research results, FTD has been more strongly linked with tau proteins than with plaques. No drugs are available: Alzheimer’s medications seem only to make things worse.
Other conditions can lead to dementia. Parkinson’s has already been mentioned. Variant CJD is another. AIDS can lead to dementia. People with Down syndrome or Huntington’s disease are at risk. Damage caused by long-term alcoholism can mimic dementia (Korsakoff’s syndrome), as can B vitamin deficiency, diabetes, kidney failure, thyroid problems, liver dysfunction, anemia, or electrolyte imbalance, though these are only apparent dementias from which people can recover.