Some evidence suggests that women are more likely then men to get the disease. An examination of the brain tissue remains the only definitive diagnosis. By integrating information from the patient's medical history, mental ability tests, and physical, psychological and neurological exams, doctors can exclude other causes of dementia and, by a careful and informed process of elimination, zero in on Alzheimer's Disease. An early diagnosis of AD is a good idea, particularly for the benefits it provides in planning for the future. So while simple memory lapses are natural in older people, whenever there is evidence of unusual difficulty communicating, thinking or reasoning, a medical diagnosis should be sought as soon as possible.
Experts caution against premature genetic testing, however.
Unless they are involved in clinical research, people who show no symptoms of Alzheimer's are discouraged from being screened for the APOE4 allele. Non-symptomatic persons with APOE4 may know their risk has increased, but within the limits of current science there is almost nothing they can do about it. Further, others might use the information adversely. An insurance company, for example, knowing that a symptom-free person carries the APOE4 allele, might be tempted to discontinue a health care policy in anticipation of a disease that may never occur. While neither halts or slows the disease, each can provide minor, temporary improvement in cognitive ability by inhibiting the breakdown of the neurotransmitter acetylcholine.