Nearly 100,000 Louisianans over 65 have Alzheimer's

An estimated 12.4% of adults age 65 or older in Louisiana have Alzheimer's disease, per a new study. That comes to about 94,700 people.

Why it matters: It's critical for public health officials, policymakers and others to have a clear look at the number of Alzheimer's cases in a given area, the authors say — in part because caring for those with the disease cost an estimated $321 billion nationwide last year, much of which came via Medicare and Medicaid.

Details: The study, published in the journal Alzheimer's & Dementia, estimated the rates of Alzheimer's disease among adults age 65 or older in a given area based on demographic risk factors, including age, sex and race/ethnicity.

• Researchers used data from the Chicago Health and Aging Project (a population-based study examining Alzheimer's risk factors), plus population estimates from the CDC's National Center for Health Statistics.

Zoom in: Orleans Parish has the state's highest rate of Alzheimer's at 15.4%.

• Other parishes with high rates include Caddo, Bienville and Claiborne in northwest Louisiana and East Carroll and Tensas in the northeastern part of the state.

By the numbers: According to the Alzheimer's Association, 200,000 family caregivers in Louisiana bear the burden of 363 million hours of unpaid care for those with the disease.

• That care is valued at $4.8 billion — and costs an estimated $765 million for the state Medicaid program.

The big picture: The eastern and southeastern U.S. have the country's highest rates of Alzheimer's disease, according to the study.

• Maryland (12.9%), New York (12.7%) and Mississippi (12.5%) topped the list of U.S. states ranked by estimated number of Alzheimer's cases.

What they're saying: "These estimates could help public health officials to understand the burden of disease (e.g., demand for caregiver counseling and institutional care) at the county and state levels and develop adequate strategies for identifying and caring for people with [Alzheimer's]," the authors write.

Yes, but: The researchers caution that their approach is incomplete, as demographic-based risk factors can only tell part of the picture.

• Other risk factors — including cardiovascular health and lifestyle — also play a role, but "such data are unavailable at the county level, and we cannot incorporate them into our estimates," they write.