ObjectiveTo assess the prevalence and moderators of low bone mass, osteopenia and osteoporosis in schizophrenia patients.
MethodMajor electronic databases were searched from inception till 12/2013 for studies reporting the prevalence of low bone mass (osteopenia + osteoporosis = primary outcome), osteopenia or osteoporosis in schizophrenia patients. Two independent authors completed methodological appraisal and extracted data. A random effects meta-analysis was utilised.
ResultsNineteen studies were included (n=3,038 with schizophrenia; 59.2% male; age 24.5-58.9 years). The overall prevalence of low bone mass was 51.7% (95% CI=43.1-60.3%); 40.0% (CI=34.7-45.4%) had osteopenia and 13.2% (CI=7.8-21.6%) had osteoporosis. Compared with controls, schizophrenia patients had significantly increased risk of low bone mass (OR=1.9, CI=1.30-2.77, p<0.001, n=1,872) and osteoporosis (OR=2.86, CI=1.27-6.42, p=0.01, n=1,824), but not osteopenia (OR=1.33, CI=0.934-1.90, p=0.1, n=1,862). In an exploratory regression analysis, older age (p=0.004) moderated low bone mass, whilst older age (p<0.0001) and male sex (p<0.0001) moderated osteoporosis. The subgroup analyses demonstrated high heterogeneity, but low bone mass was less prevalent in North America (35.5%, CI=26.6-45.2%) than Europe (53.6%, CI=38.0-68.5%) and Asia (58.4%, CI=48.4-67.7%), and in mixed in-/outpatients (32.9%, CI=49.6-70.1%) versus inpatients (60.3%, CI=49.6-70.1%).
Conclusion
3Reduced bone mass (especially osteoporosis) is significantly more common in people with schizophrenia than controls.
Summations• Low bone mass affects more than half of patients with schizophrenia and is approximately twice as common compared to age-and sex-matched controls.• Osteoporosis is over two and a half times more common in patients than in controls.• Multidisciplinary teams should routinely screen and implement appropriate interventions targeting bone health.
Considerations• There was a paucity and inconsistency in the reporting of factors that may influence the prevalence of low bone mass across studies.• All of the studies included were cross-sectional; therefore directionality of the association between the variables investigated and the observed low bone mass cannot be deduced with certainty.• We could not clearly elucidate the influence of antipsychotics since there were inadequate data on specific medications.