Osteoporosis, schizophrenia and antipsychotics: the need for a comprehensive multifactorial evaluation.

Osteoporosis is recognised as a major public health issue leading to bone fractures, pain and disability. Awareness of an elevated risk of osteoporosis in individuals with schizophrenia is increasing. An accelerated decrease in bone mineral density (BMD) in patients with schizophrenia may be disease related or drug induced. A drug-induced decrease in BMD has been attributed mostly to hyperprolactinaemia and its consequences. However, as demonstrated in this review, decreased BMD and osteoporosis are multifactorial processes, and abnormal bone structure and functions are not limited to BMD. Multiple dynamic processes may lead to impairment of bone homeostasis and eventually to bone abnormalities. Many of these processes may be abnormal in treated as well as untreated patients with schizophrenia. Despite many publications, the epidemiology of abnormal bone structure, mineralisation and dynamics in patients with schizophrenia is still not fully determined. Comprehensive studies of bone dynamics in individuals with first-episode schizophrenia, as well as in patients treated with various current medications, are needed in order to characterise the problem(s) and then to develop relevant treatment and prevention strategies.