TORONTO, July 27 (UPI) -- Men with Alzheimer's disease are often misdiagnosed earlier in life, suggesting a relationship between sex and age of onset, say researchers at the Mayo Clinic.
Though age is the biggest risk factor for Azheimer's, there are key differences between how it develops in the brains of men and women, suggesting the symptoms presented to doctors could be to blame for men not being properly diagnosed until later in the disease's progression, according to a study presented at the Alzheimer's Association's International Conference.
"This study goes much deeper than just looking at the difference between the number of women and men diagnosed," Dr. Maria Carrillo, chief science officer for the Alzheimer's Association, said in a press release. "It calls attention to the process of diagnosis and other lifelong factors that may influence diagnosis and timing and duration of the disease."
Using data from the State of Florida brain bank, researchers analyzed the records of 1,606 Alzheimer's disease patients between the ages of 37 to 102, considering data on education, family history, age of onset, disease duration, cognitive test results and genetic risk for the disease.
Overall, men were younger at the age of Alzheimer's onset, were commonly misdiagnosed initially, and had shorter disease duration. The data showed a prevalence of Alzheimer's among men their 60s.
Among women, most had lower education and died at an older age, with frequency of the disease overrepresented among women in their 70s, 80s and 90s.
"Our study demonstrates that there may be an interaction between age of onset and sex-based differences," Dr. Melissa Murray, an assistant professor at Mayo Clinic, said in a press release.
"In our study population, neuropathologically diagnosed Alzheimer's was observed at the same frequency overall in both sexes, but occurred quite differently depending on the age range being examined. Atypical clinical presentations were more common in men, suggesting that their lower reported prevalence of Alzheimer's may be a result of the disease not being accurately recognized in life," Murray added.