Osteoporosis Drugs Associated With Lower Alzheimer's Risk in 120,000-Person Study

Widely used osteoporosis drugs known as nitrogen-containing bisphosphonates (NBPs) were associated with a lower risk of Alzheimer's disease and related dementias (ADRD) in a study of more than 120,000 older adults, researchers at the University of Hong Kong reported. NBPs such as alendronate and zoledronate are already prescribed to strengthen bones and reduce fractures in people with osteoporosis.

The researchers analyzed medical records of more than 120,000 people age 60 and older in Hong Kong who had osteoporosis or fragility fractures between 2005 and 2020, comparing dementia risk among those taking NBPs, those on other osteoporosis medications, and those who received no treatment. People taking NBPs had a 16% lower risk of developing Alzheimer's disease and related dementias than untreated patients, and a 24% lower risk than those on other osteoporosis drugs. The association was particularly strong among women and people with hip fractures.

Osteoporosis and dementia often affect the same older populations and share risk factors such as advanced age, female sex and reduced physical activity; the same team has previously found osteoporosis and fractures to be independent risk factors for dementia. "Our study provides evidence that NBPs may offer dual benefits in strengthening bones and reducing fracture risk, as well as potentially preventing ADRD," said Professor Cheung Ching-lung of the Department of Pharmacology and Pharmacy at the University of Hong Kong's HKUMed.

Based on their estimates, the researchers said treating 48 patients with NBPs for five years could potentially prevent one case of dementia. New disease-modifying Alzheimer's treatments have begun to emerge, but questions remain about their cost and accessibility, increasing interest in repurposing existing, widely available medications such as NBPs.

More than 55 million people are currently living with dementia worldwide, a number projected to reach 139 million by 2050, according to the World Health Organization, which has designated dementia a critical health priority. The study was published in the journal Alzheimer's & Dementia.