Osteoporosis in patients with schizophrenia

Osteoporosis is regularly mentioned as a possible consequence of treatment with prolactin-increasing antipsychotic medications, but little is known about the prevalence and the degree of loss of bone mineral density in patients suffering from schizophrenia. The authors' goals were to investigate the association between schizophrenia and a decrease in bone mineral density and to get more insight into potential underlying pathophysiological mechanisms.

In a cross-sectional study, the authors used dual x-ray absorptiometry to determine bone mineral density of 75 inpatients and outpatients suffering from schizophrenia. All patients had been treated with antipsychotics for at least 1 year, and only patients between the ages of 19 and 50 were studied to exclude patients with age-related idiopathic osteoporosis.

In men but not women with schizophrenia, bone mineral density was significantly lower than normal in the lumbar region. A comparison of loss of bone mineral density in male and female patients showed significant differences between the sexes. Bone mineral density showed a negative correlation with negative symptoms and Positive and Negative Syndrome Scale total score and a positive correlation with 25-hydroxy-vitamin D3 levels and body mass index in male patients. In female patients, a positive correlation between body mass index and bone mineral density was found. Exposure to prolactin-increasing antipsychotics was not related to bone mineral density.

The male patients with schizophrenia in this study suffered from low bone density. This finding as well as other reports lend support to directing more attention to bone metabolism in patients with schizophrenia, although there is no universally accepted screening policy to identify individuals at high risk for osteoporosis.