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Copyright 1996 The New York Times Company
The New York Times
February 21, 1996, Wednesday, Late Edition - Final
SECTION: Section A; Page 12; Column 1; National Desk
LENGTH: 1794 words
HEADLINE: Research Links Writing Style to the Risk of Alzheimer's
BYLINE: By GINA KOLATA
Alzheimer's disease, the dreaded affliction of old age, might show its first subtle
effects when its victims are as young as 20.
In a study based on the autobiographies of young women about to join an order
of nuns, researchers have reported that the women's writing styles when they
were in their 20's predicted with uncanny accuracy which of them would be
severely demented with Alzheimer's disease six decades later. The study was published today
in the Journal of the American Medical Association.
The 93 nuns in the study were born before 1917. Four years after they
entered the convent, just before they took their vows and permanently joined the
School Sisters of Notre Dame, they were asked to write brief autobiographies.
Now the women are in their 80's, and nearly a third have developed
Alzheimer's disease -- an incidence similar to that found in the general
population. Fourteen have died, and autopsies were done on their brains to look
for definitive marks of Alzheimer's disease.
When the investigators, most of them at the University of Kentucky, began
their study, they expected to find that education and an active mind protected
against Alzheimer's disease. But, to their surprise, they found that education
offered no protection, at least in this study group. Instead, they found hints that Alzheimer's
disease could have already begun in some women by the time they entered the convent.
The nuns whose sentences were grammatically complex and packed with ideas
when they were in their 20's remained sharp of mind when they were in their
80's. In contrast, almost all those whose sentences were simple and
comparatively devoid of complex grammatical constructions were demented six decades later.
The researchers found that, without knowing the fate of the writer of each
sample, they could use their writing to predict with 90 percent accuracy which
ones would develop Alzheimer's disease when they were old.
The advantage of studying the nuns, the investigators noted, was that they
lived together in the same environment for 60 years, so vagaries of diet or
other environmental influences did not affect their Alzheimer's risk. All were
white, and they had similar backgrounds. So this study does not address the question of whether
race, reproductive history, diet or environment can affect the risk of Alzheimer's
The most telling linguistic feature was idea density, a measurement, imported
from the field of psycholinguistics, that looks at how many ideas are in a given
piece of writing. Dr. Susan J. Kemper, a psycholinguist who is an author of the
study, said that researchers used idea-density measurements to categorize texts according to
how difficult they are to read and understand.
In the nuns study, one rater analyzed the autobiographies, without knowing
whether the nuns who wrote them had developed Alzheimer's disease, and a second
rater independently checked 10 of them. The two raters concurred nearly 90
percent of the time.
The two nuns in the study whose writings were at the extremes when rated for
idea density were both 20 years old when they wrote their autobiographies, and
both had high school degrees. One wrote: "At the time of my entrance, I was in
good health and had had no serious illnesses before this time."
The other nun wrote: "Now I am wandering about in 'Dove's Lane' waiting, yet
only three weeks to follow in the footprints of my Spouse, bound to Him by the
Holy Vows of Poverty, Chastity, and Obedience."
The first nun got bachelor's and master's degrees and died of Alzheimer's
disease about six decades later. The second nun got a bachelor's degree and is
still alive, her mind keen and her memory intact.
Dr. James A. Mortimer, an Alzheimer's researcher at the University of South
Florida and an author of the study, said that he could hardly believe the
results because he had hypothesized that continuing education might help keep
aging brains sharp and prevent Alzheimer's.
"To me, it was the most bizarre finding on earth," Dr. Mortimer said. But he
added that he was now convinced that Alzheimer's disease might well be "a
lifelong disease," one that progresses very slowly and manifests itself as
dementia only when a certain threshold in brain damage is reached.
The development and progress of Alzheimer's disease seem to be influenced by
genetic factors, Dr. Mortimer added. Researchers have identified a handful of
genes that cause Alzheimer's disease in families and have found others
indicating a predisposition to the disease. In that sense, Dr. Mortimer said, Alzheimer's disease
might be like atherosclerosis, which is also most likely in people with genetic
predispositions and which can first appear as fatty streaks on the walls of arteries
when people are in their 20's and are showing no obvious symptoms.
Other researchers said they had also struggled with disbelief when they
learned of the study results but found the research design elegant and the
evidence compelling. Many said the study might mark a turning point in the way
researchers think about Alzheimer's disease.
The findings are "remarkable," and the study "pivotal," said Dr. Zaven
Khachaturian, who directs the Ronald and Nancy Reagan Institute of the
Dr. Richard Suzman, who is chief of the demography and population
epidemiology branch of the National Institute on Aging, said, "It's an elegant
study, and I think it's going to set off a gold rush of research looking for
other samples to confirm or disconfirm these results."
Dr. Neil Buckholtz, who directs Alzheimer's disease research at the National
Institute on Aging, cautioned that the results might not mean that Alzheimer's
disease starts when people are in their 20's. Another hypothesis, he said, is
that "there's a difference in the brains of these two groups of people and that interacts with
the process of Alzheimer's that may be occurring somewhat later."
"We do know that whatever the process of Alzheimer's disease is, it occurs
earlier than the symptoms," Dr. Buckholtz said. "We really don't know at this
point how far back it goes."
But Dr. Khachaturian said the conclusion of this study also fit with that of
a group of German researchers, headed by Tomas G. Ohm of J. Guntenberg
University in Mainz, who examined 887 brains of people 20 to 104 years old and
concluded that neurofibrillary tangles, the pathological changes characteristic of Alzheimer's
disease, could be present even when people were 20 years old.
In a recent paper published in Neuroscience, the German group concluded that
"the deep roots of Alzheimer's disease-related neurofibrillary changes can be
traced about 50 years back and may even extend into adolescence."
The director of the nuns study, Dr. David A. Snowden, said that he and his
colleagues had begun their research expecting that nuns who had spent their
lives teaching would be less likely to develop Alzheimer's disease than those
with a high school education or less who had handled household chores at the convent.
But the researchers found no such effect. When the investigators restricted
their analysis of the writing samples to the 85 nuns with college degrees, "the
results were just as striking," Dr. Snowden said.
Dr. Kemper said it was not yet known whether idea density was related to
intelligence or to measures like verbal scores on college entrance exams or an
ability to do well on analogies tests. But she and others will be addressing
such questions, she said.
The investigators also looked at the nuns' writings when they were older to
see if the idea density in their writings remained constant. It did. Those with
the prose rated most dense in ideas when they were 20 had the most idea-dense
prose when they were 80, and vice versa.
Dr. Snowden cautioned that the striking findings from the nuns study needed
to be confirmed. He said there were other troves of writings that might be mined
for future studies. "There may be archives in universities of essays written for
college applications," he said.
The investigators are also working with Dr. Allen D. Roses of Duke University
to see if one genetic risk factor, the inheritance of apo E4 genes, was more
prevalent among the nuns whose writings had low idea densities.
One thing the study shows, Dr. Roses said, is that "we ought to be less
seriously wed to our beloved hypotheses."
2 Lives: Early Signs of Alzheimer's?
Here are excerpts from the autobiographies of two nuns, written when they were
20 years old. Researchers say the writings hold clues indicating who would
develop Alzheimer's disease. The researchers have changed proper nouns and dates
to protect the nuns' privacy.
SISTER A. She developed Alzheimer's, which was confirmed in an autopsy after she
died at age 80. She had 12 years of education at the time she wrote her
autobiography and went on to earn bachelor's and master's degrees.
"I was born in Eau Claire, Wis., on May 24, 1913 and was baptized in St. James
Church. My father, Mr. L. M. Hallacher, was born in the city of Ross, County
Cork, Ireland, and is now a sheet metal worker in Eau Claire. . . . There are
ten children in the family six boys and four girls. Two of the boys are dead. I attended St.
James grade and high school and made my First Holy Communion in June 1921. .
. . At the time of my entrance I was in good health and had had no serious illness
before this time. A good example given to me by my teachers and the true religious spirit
that they showed did much in directing my steps to Notre Dame. I entered in August
1928, and was received June 17, 1932. I prefer teaching music to any other profession."
SISTER B. She showed excellent mental function at the age of 80 and is still
living. She also had 12 years of education when she wrote this account and went
on to earn a bachelor's degree.
"The happiest day of my life so far was my First Communion Day which was in June
nineteen hundred and twenty when I was but eight years of age, and four years
later in the same month I was confirmed by Bishop D. D. McGavick. In nineteen
hundred and twenty-six I was graduated from the eighth grade and now my great desire of entering
the convent was soon to be gratified. The following September at the age of fifteen,
I came to Milwaukee to dear Notre Dame. The following vacation I spent with my
parents. I visited the capitol in Madison and also the Motherhouse of the Franciscan
Sisters of Perpetual Adoration in Duluth which visit increased my love for Notre
Dame. . . . Now I am wandering about in 'Dove's Lane' waiting, yet only three
weeks to follow in the footprints of my Spouse, bound to Him by the Holy Vows of
Poverty, Chastity, and Obedience."