Bone mineral density and its relationship to prolactin levels in patients taking antipsychotic treatment

Antipsychotic treatment is frequently associated with elevated prolactin levels. Raised prolactin levels have been linked with osteoporosis. The objective of this study is to determine whether patients taking antipsychotics show reduced bone mineral density (BMD), and whether this is associated with prolactin levels. BMD (standardized as z scores) was compared using dual x-ray absorptiometry of the lumbar spine and hip in patients taking antipsychotics (n = 102, mean age: 46.0, SD: 13.1, 47% male, median treatment duration: 3.0 years) to matched reference controls. Levels of prolactin, markers of bone metabolism, and risk factors for osteoporosis were measured. Mean BMD was not significantly reduced, other than the total spine score for black males (mean z score: -0.88, P = 0.00001). BMD was correlated with body mass index but there was no correlation with prolactin. BMD was not correlated with prolactin levels and showed no clinically significant reduction. The low BMD in black males warrants further investigation.