Exercise earlier in life may help delay the disorder.

* THE QUESTION So far there's no cure for Alzheimer's disease, and researchers don't know exactly what causes the brain disorder, which affects memory, language and behavior, most commonly in old age. For many people, preventing or delaying the disease has become a goal. Might physical activity earlier in life affect the onset of Alzheimer's?

* THIS STUDY involved 1,449 people who had been examined at midlife and surveyed about their physical activity. About 21 years later, at ages 67 to 79, they were reexamined and given cognitive tests, with 72 people diagnosed with Alzheimer's. Those who had engaged in physical activity outside their jobs at least twice a week during middle age -- exercise that caused them to sweat and breathe hard -- were about 62 percent less likely to have Alzheimer's than were the more sedentary people. The beneficial effect of exercise was stronger in people genetically predisposed to Alzheimer's through presence of the ApoE gene.

* WHO MAY BE AFFECTED BY THESE FINDINGS? All adults, especially those at or nearing middle age. An estimated 4 1/2 million Americans have Alzheimer's, a number that has more than doubled in the past quarter-century and includes about 10 percent of all people over age 65 and nearly half of those over 85.

* CAVEATS The study did not differentiate among various types and intensities of physical activity.

* FIND THIS STUDY Oct. 4 online edition of Lancet Neurology; abstract available at (click "Early Online Publication").

* LEARN MORE ABOUT Alzheimer's disease at and

macular degeneration

Injections appear to stem vision loss when given early.

* THE QUESTION The most severe type of age-related macular degeneration, known as wet AMD because of leaking fluid from abnormal blood vessels in the eye, often exhibits few symptoms early on. Once established, it can be treated though not cured and it often leads to blindness within two years. Might Macugen (pegaptanib sodium) -- a drug approved in December to slow the vision loss of people with advanced wet AMD -- help preserve sight if given earlier?

* THIS STUDY analyzed data on 127 people, aged 50 or older and diagnosed with early wet AMD, who were injected with Macugen or a placebo nine times in 48 weeks. Participants were divided into two groups that received the drug and two that took a placebo. After 54 weeks, visual acuity (detail, sharpness) had declined less in people given Macugen; they could distinguish an average of four to six fewer letters on an eye chart than at the start of the study, compared with 17 fewer for the placebo groups. About 3 percent of one Macugen group and 10 percent of the other (vs. 29 and 23 percent of the placebo groups) had severe vision loss at the end of the study. In addition, 12 percent of one Macugen group and 20 percent of the other experienced improved vision -- they were able to identify 15 more additional letters on an eye chart -- compared with 4 percent of one placebo group and no one in the other group.

* WHO MAY BE AFFECTED BY THESE FINDINGS? People with wet AMD, which can occur in middle age but usually develops later in life and affects women more often than men.

* CAVEATS Analysis involved a relatively small number of people. The study was funded by Eyetech Pharmaceuticals and Pfizer, which developed and market the drug.

* FIND THIS STUDY October issue of Retina; abstract available online at

* LEARN MORE ABOUT macular degeneration at and

cognitive decline

Eating more fish seems to slow the loss of mental abilities.

* THE QUESTION Many people have increased the amount of fish in their diet because of the protective effect its omega-3 fatty acids can have on the heart. Might fish also benefit the brain -- specifically the thinking, memory and language skills that so often wane as people age?

* THIS STUDY analyzed data on 3,718 people, aged 65 and older, who completed questionnaires about the foods they ate and were given a battery of cognitive tests three times in six years. Overall, cognitive ability declined during this time. It fell 10 percent more slowly every year among people who ate fish at least once a week and 13 percent more slowly among those who ate fish two or more times a week than among those who consumed it less often. The authors described the benefit as the equivalent of being three to four years younger.

* WHO MAY BE AFFECTED BY THESE FINDINGS? Older people. Although some mental changes occur as people get older, more serious decline, or dementia, is not a normal part of aging.

* CAVEATS The study did not determine whether certain components of fish were more beneficial than others.

* FIND THIS STUDY December issue of the Archives of Neurology; abstract, published early online, available at

* LEARN MORE ABOUT elements of cognitive decline at (search for "forgetfulness") and (search for "memory loss").

-- Linda Searing

The research described in Quick Study comes from credible, peer-reviewed journals. Nonetheless, conclusive evidence about a treatment's effectiveness is rarely found in a single study. Anyone considering changing or beginning treatment of any kind should consult with a physician.