Fourteen percent of adults aged 75 or more years have subjective cognitive decline, one of the earliest noticeable symptoms of Alzheimer’s disease, according to new data from the Centers for Disease Control and Prevention.

SCD is “the self-reported experience of worsening or more frequent confusion or memory loss within the previous 12 months,” the federal agency reported in Friday’s edition of the “Morbidity and Mortality Weekly Report.” The data come from more than 220,000 respondents to 2015 and 2016 Behavioral Risk Factor Surveillance System surveys.

Additionally, the CDC found that 10% of those aged 65 to 74, 11% of those aged 55 to 64, and 10% of those aged 45 to 54 had SCD.

Overall, the rate of SCD was highest in Nevada, at 16.3%, and Arkansas, at 16.2%. Thirty-seven percent of all respondents said that SCD interfered with their ability to work, volunteer or participate in social activities, and 40% said they had given up household activities or chores because of it, but 55% said they had not discussed it with a healthcare professional.

“Adults with confusion or memory loss should talk to a healthcare professional who can assess cognitive decline and address possible treatment of symptoms, management of other co-occurring chronic health conditions, advance care planning, and caregiving needs, and who ensures that the patient receives appropriate information and referrals,” the authors said.