"A small pilot study has found preliminary evidence that squirting insulin deep into the nose where it travels to the brain might hold early Alzheimers disease httphealth.nytimes.comhealthguidesdiseasealzheimersdiseaseoverview.htmlinlinenytclassifier at bay researchers said on Monday. It comes at a time when there are no effective ways to prevent or delay the progress of Alzheimers. And although the results are preliminary and must be viewed with caution it is a provocative study said Dr. Jason Karlawish an Alzheimers researcher and ethicist at the University of Pennsylvania. But he and other experts caution that a bigger and longer study is needed to see if the initial results hold up and whether there are adverse effects that might negate any benefits. Its important readers realize this is a pilot trial said Dr. P. Murali Doraiswamy an Alzheimers researcher at Duke University who was not part of the study. Its not ready for prime time. The study published online in the Archives of Neurology httparchneur.amaassn.orgcgicontentfullarchneurol.. included  people a group small enough that the promising results could have occurred by chance. Researchers at the University of Washington divided the subjects into three groups. One got a placebo one got  international units of aerosolized insulin a day and the third got  international units a day. In the fourmonth study the group randomly assigned to receive intranasal insulin twice a day either improved slightly or remained the same in tests of memory and assessments of their ability to handle daytoday activities. The lower dose seemed more effective than the higher one. Those who received placebos got worse. A third also had scans to assess their brains use of glucose. One hallmark of Alzheimers disease is reduced metabolism in the brain which shows up on scans as less use of glucose the fuel for brain cells. In this assessment those getting insulin used more glucose in their brains those taking placebos used less. For years the studys principal investigator Suzanne Craft has studied insulins effects in Alzheimers. She is professor of psychiatry httptopics.nytimes.comtopnewshealthdiseasesconditionsandhealthtopicspsychiatry_and_psychiatristsindex.htmlinlinenytclassifier at the University of Washington in Seattle and director of the memory disorders clinic at the Veterans Affairs Puget Sound Health Care System. Brain cells need insulin Dr. Craft said. And conditions in which the body makes too little insulin or is resistant to its effects  diabetes httphealth.nytimes.comhealthguidesdiseasediabetesoverview.htmlinlinenytclassifier prediabetes even untreated highblood pressure httphealth.nytimes.comhealthguidestestbloodpressureoverview.htmlinlinenytclassifier  are associated with an increased risk of Alzheimers. In addition she said beta amyloid a toxic protein that accumulates in the brain of Alzheimers patients seems to tie up insulin in the brain. So Dr. Craft reasoned perhaps if more insulin could be put into the brains of people with the degenerative brain disease their memories and ability to function might improve. The problem was to find a way to get more insulin to the brain but not to the body. The solution was a special device made by Kurve Technology that delivers a spray of insulin deep into the nose. From there the hormone travels along the path of nerves into the brain. The investigators first tried a single dose of insulin delivered via nasal spray to the brains of people with Alzheimers disease. Their memories improved temporarily. Then they tried giving insulin daily for three weeks. Again the hormone seemed to help. That led to the current study lasting four months. But Dr. Martha Daviglus of Northwestern University who led a panel last year that assessed published papers on preventing and treating Alzheimers urged caution. In her field cardiovascular medicine she has seen many exciting findings in small studies that fall apart in larger or longer ones. Now Dr. Craft wants to test insulin again in a much more extensive study. . In the meantime she cautions Alzheimers patients not to rush out and try to take insulin. It is too soon to say if the treatment is even safe she said. And patients would need a special device to get it deep into the nose. Kurves device is not yet on the market. The individual person will not be able to get this device Dr. Craft said. But she added if her study goes forward many will be able to participate in it."