As is said of old soldiers, Ronald Reagan did not die; he just faded away. That is the cruel essence of the disease that slowly carried our 40th president into the sunset. Once thought to be a natural consequence of old age, senility was simply accepted as the way things were. Not anymore. We now know that most of the time such dementia is Alzheimer's disease, a complex disorder of brain metabolism that attacks the mind, destroys the intellect, distorts the personality, and in its final chapter leaves a primitive brain unable to think and barely able to keep the rest of the body alive. No, it is not inevitable to aging, but it is age related, with almost half of those over age 85 in some stage of its terrifying grip.
Alzheimer's knows no mercy in its near-decade-long course. Barely noticeable early on, it relentlessly nibbles at the neural networks of the brain, first attacking the memory pathways, then spreading like an oily wave to engulf the higher cerebral centers. An organ known for its commanding might diminishes to a shrunken shadow of itself, choked with waxy protein clumps called amyloid. Millions of its neurons disappear in a process that remains one of the biggest mysteries of medicine.
Amyloid is the favored culprit. In its normal state it's a benign protein on the outer surface of nerve cells. But when misbehaving enzymes shred it into small insoluble fragments, a toxic form is spewed out into the surrounding tissue. There it interrupts nerve connections and, most neuroscientists believe, triggers a slow death of surrounding nerve cells, turning the cells' internal structures into telltale tangled junk. Nature and nurture are both at work here. Several genes linked to cholesterol or to amyloid processing play a big role in the metabolic derangements, but a wide range of external factors seems to have influence as well. Statins, anti-inflammatory agents, sometimes estrogen, and diets rich in fruits and vegetables are linked to less disease; prior head trauma, low education levels, high LDL cholesterol, and high blood pressure, with more.
Medicines that increase brain chemicals, like serotonin, or the memory molecule, acetylcholine, or those that protect surviving cells from overwork sometimes soften Alzheimer's blow, but there are no magic bullets as yet. Several research strategies on the horizon, however, taken together, have a chance of stopping if not reversing the brain decay. Getting rid of toxic amyloid is a big one. In development are medicines that block the clipping enzymes that produce the waxy debris, and vaccines to clean it up once there. Then there is the promise of drugs to help neurons survive a toxic assault, and, long term, for adult stem cell revival to replace these renewable cells that are also damaged or lost in this disease. These approaches demand better technology to identify the disease early, before the toxic mess has spread too far and brain loss is beyond repair. Not simple tasks--but doable.
As we have seen before when a seemingly hopeless disease calls for aggressive research, national resolve makes all the difference. The illnesses that have benefited most bountifully from public largess almost always had patron saints to stir that public will. Ronald Reagan believed in patron saints. He also believed in basic research and technology to help them along. As president he spoke with awe of science that would protect this nation, strengthen its economy, and cure its medical ills. In 1994, when he and his wife, Nancy, disclosed his illness, they began a crusade on behalf of Alzheimer's research, which she is continuing. History tells us that these efforts will be rewarded. At critical moments beloved presidents have led the nation in patronage of a medical cause born of their own illness. Franklin Roosevelt, disabled by polio, made his birthday a national giving time for the March of Dimes so that others might walk. After his near-fatal heart attack in 1955, Dwight Eisenhower became a champion for research and public awareness of this killer. Both brought their stature and their vulnerability into peoples' living rooms and inspired the national will to fight for all those suffering.