Risk of hip fracture in patients with a history of schizophrenia

Background There is evidence of an association between decreased bone mineral density, schizophrenia, and prolactin-raising antipsychotic medication. However, it is not known whether this is clinically significant. Aims To investigate whether patients with a history of schizophrenia are at increased risk of hip fracture. Method In a case -control study, we compared cases of 'hip fracture' on the General Practice Research Database (n=16341) with matched controls (n=29889). Results Hip fracture was associated with schizophrenia (OR=1.73; 95% CI 1.32-2.28), and prolactin-raising antipsychotics (OR=2.6; 95% CI 2.43-2.78), in the univariate analysis. In the multivariate analysis, prolactin-raising antipsychotics were independently associated with hip fracture but schizophrenia was not. A significant interaction between gender and antipsychotics was found in the association with hip fracture (P=0.042); OR=2.12 (95% CI 1.73-2.59) for men, OR=1.93 (95% CI 1.78-2.10) for women. Conclusions The association between prolactin-raising antipsychotic medication and hip fracture may have serious implications for public health. Mental health service patients may require preventive measures including dietary and lifestyle advice. Declaration of interest None. Funding detailed in Acknowledgements.