Glucocorticoid-Induced Osteoporosis

For the past month, a 75-year-old woman with polymyalgia rheumatica has received prednisone at a dose of 20 mg daily. The treatment plan is to try to taper the dose to 5 mg daily within 6 months. Given typical durations of treatment, the expectation is that she will continue to receive prednisone for 2 years. She is otherwise healthy and has no personal or family history of fracture. She does not smoke or drink alcohol. Her height is 168 cm, and she weighs 68 kg. Her serum 25-hydroxyvitamin D level is 30 ng per milliliter (74 nmol per liter). Her bone mineral density T score is -1.2 at the femoral neck. What would you advise to prevent glucocorticoid-induced osteoporosis and fracture?