[2][3] Patients that both form kidney stones and have hypercalciuria are at increased risk for bone loss leading to osteoporosis.
[4] There are a number of causes of hypercalciuria including genetic (idiopathic), primary hyperparathyroidism, immobilization, pagets disease, Multiple Myeloma, Calcium excess, Vitamin D excess/increased sensitivity, drug-induced hypercalciuria, sarcoidosis, hyperthyroidism, Cushing's disease, and renal tubular acidosis.
Despite a potential genetic component, urine calcium levels can be influenced by dietary items including sodium, protein, and sugars.
[1] Potassium citrate in conjunction with thiazide diuretics is another medication that has been shown to have a positive impact on bone formation but also decrease the crystallization of calcium based stones in the kidneys.
[1][4] Other drugs are used to treat osteoporosis, including bisphosphonates, but have not been shown to have an effect on urine calcium levels.