Background: Patients with schizophrenia are at increased risk for developing osteoporosis, which has historically been attributed to poor diet and lack of exercise. However, more recent data suggest a link between antipsychotic use and osteoporosis due to increased prolactin levels. Hyperprolactinemia can lead to suppression of hypothalamus-pituitary axis regulation of sex hormone production and over time, hypogonadism, which can affect bone health. There have been a few studies evaluating the link between antipsychotic use and osteoporosis; however, the link is not well established and there is very little guidance regarding monitoring of prolactin levels.
Objectives:Determine the prevalence of osteoporosis in patients receiv ing antipsychotic medications.
Evaluate the duration of antipsychotic therapy, prolactin levels (prevalence of monitoring and mean levels), and incidence of fractures for the study patients diagnosed with osteoporosis.
Methods:The study was a retrospective cohort study evaluating patients 18 years of age and older who were prescribed an antipsychotic at the Dallas VA Medical Center from 1/1/2008-12/31/2009. The patients included had to be taking the same antipsychotic for at least one year. Subjects were excluded if they had significant co-morbidities or were taking other medications that increase osteoporosis risk. Patient demographics, antipsychotic information, and pertinent lab values such as vitamin D, prolactin, testosterone and FSH/LH levels were recorded. The use of other medications that may increase prolactin, smoking status, bone mineral density, and history of fracture were also noted.
Results:This study showed that 26% of patients taking antipsychotics for at least one year develope d osteoporosis. The dose or type of antipsychotic (prolactin-sparing versus prolactin-raising) did not appear to be contributing factors. Based on this study's data, the duration of antipsychotic therapy and the concurrent use of other prolactin raising medications may be more concerning.