Bone mass reduced in older schizophrenia patients
MedWire News: Results from a Japanese study show that older patients with schizophrenia have significantly reduced bone mass compared with the older general population.
Writing in the Annals of General Psychiatry, Norio Sugawara (Hirosaki University School of Medicine) and team observe that previous studies have shown that patients taking antipsychotic medications are at increased risk for bone fractures.
"The onset of schizophrenia typically occurs during adolescence and young adulthood, therefore, the administration of antipsychotic medications generally begins during the same period, during which bone maturation results in peak bone mass," they explain.
But they add that "to date, there have been a limited number of studies comparing bone mass between patients with schizophrenia and the general population."
To investigate further, the team studied 362 patients with schizophrenia or schizoaffective disorder, aged 20 years and older (mean age 49 years), and 832 mentally healthy individuals (controls) with a similar age range (mean age 57 years).
All of the participants were assessed for bone mass using quantitative ultrasound densitometry of the calcaneus, and mean osteosono-assessment index (OSI) values were calculated for male and female patients and controls in six age groups (20-29, 30-39, 40-49, 50-59, 60-69, and 70 years and older).
The researchers found that there were no significant within-gender differences in OSI values between patients and controls among those aged 39 years and younger. However, among men aged 40 years and older, and among women aged 60 years and older, schizophrenia patients showed significantly reduced OSI values compared with controls.
Specifically, male schizophrenia patients aged 40-49, 50-59, 60-69, and 70 years and older had respective mean OSI values of 2.76, 2.68, 2.57, and 2.10, compared with corresponding values of 2.96, 2.86, 2.87, and 2.84 among male controls in these age groups.
Female schizophrenia patients aged 60-69 and 70 years and older had respective mean OSI values of 2.20 and 2.08, compared with corresponding values of 2.37 and 2.27 among female controls.
Sugawara and colleagues conclude: "This study has shown that the patients with schizophrenia have lower bone mass than the general population in older age groups."
They add that the gender differences among schizophrenia patients with regard to changes in bone mass associated with aging "indicate that intervention programs to either prevent or delay the onset of osteoporosis among schizophrenic patients might be tailored separately for each gender."
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By Mark Cowen