Current treatments for osteoporosis use extremely effective drugs to reduce fracture risk. It is well known, however, that in common clinical practice the expected therapeutic effect might not correspond to the one actually obtained. In fact, some patients have a suboptimal response to treatment in terms of fracture reduction and risk.
Such clinical picture is also known as inadequate response to anti-fracture therapy. The possibility of an inadequate response to treatment seems to be correlated to multiple factors, including the advanced age of the patient, a non-optimal treatment compliance, a very high fracture risk at the beginning of treatment, and many others. Nevertheless, for many years it has been known that untreated hypovitaminosis D is able to reduce the effects of osteoporotic medication in a clinically significant way.