Effect of Acetylcholinesterase Inhibitors on Bone Metabolism

This study is investigating whether medications used to treat cognitive decline (acetylcholinesterase inhibitors, such as donepezil) also affect bone density and bone health as a side effect — which could be important for patients at risk of osteoporosis. **You may be eligible if...** - You have been diagnosed with cognitive impairment (such as mild cognitive impairment or Alzheimer's disease) - You are planning to start treatment for cognitive impairment - Women must be over 55 or post-menopausal; men must be over 50 - You speak English - You do not currently show signs of significant depression **You may NOT be eligible if...** - You are already taking donepezil, another acetylcholinesterase inhibitor, or memantine - You have heart rhythm problems (such as bradycardia or heart block) that make donepezil unsafe - You are already taking osteoporosis medications Talk to your doctor to see if this trial is right for you.