Posted by Phillipa on January 29, 2010, at 23:32:35
Strange article study on anticonvulsive use in bipolar and non bipolars and fracture and use of time of meds? Phillipa
From Reuters Health Information
Anticonvulsants Increase Fracture Risk in Patients With, and Without, Bipolar DisorderNEW YORK (Reuters Health) Jan 27 - In patients with bipolar disease who use anticonvulsants as mood stabilizers, the drugs increase the risk of fracture - but not as much as they do among individuals with no serious mental disorders.
On the other hand, patients with bipolar disease have a higher risk of fracture regardless of anticonvulsant use, according to the authors of a report in the January 12th online issue of the American Journal of Geriatric Psychiatry.
Out of 67,387 study subjects aged 50 and older, 29,002 had bipolar disorder and 19,635 had ever used anticonvulsant medications. Overall, 65% of patients with bipolar disorder used anticonvulsant medications, compared to 2% of those without serious mental illness.
There were 4367 incident fractures during 4.5 years of follow-up. In the overall analysis, the fracture rate per 1000 person-years was 37.5 in anticonvulsant users compared with 14.2 in never users. This translates into a 2.42-fold increased risk of fracture with anticonvulsant use.
The association of anticonvulsants with fracture was stronger in subjects without bipolar disorder, however. The drugs increased the risk of fracture 2.31-fold in subjects with bipolar disorder versus 3.03-fold in subjects without any serious mental illness. Bipolar disorder itself was associated with a 1.21-fold increased risk of fracture.
The effect of anticonvulsant use on fracture risk "persisted for at least 6 months after cessation of use," the authors said. They also found that fracture risk was highest when patients had been taking anticonvulsants for 1 to 2 years, and after 3 years, anticonvulsant therapy "was no longer significantly associated with fracture."
These latter findings might be due at least in part to the fact that patients who'd been taking the drugs for 3 years or more were significantly younger, and had significantly fewer comorbidities, compared to patients who took them for less than 6 months.
"Patients with bipolar disorder often use medications for many years or even decades to treat their condition, and as these individuals age, the influence of these medications on overall health may also change," lead investigator Dr. Briana Mezuk from Virginia Commonwealth University School of Medicine, Richmond, told Reuters Health in an email. "Bone health is particularly important to maintain in older age, and treatment guidelines for bipolar disorder should account for this aging process."
The subjects for the new study were receiving care through the Veterans Administration and were followed from 2002 until 2006.
"This study builds on recent work suggesting that many classes of psychiatric medications may influence bone health among older adults," Dr. Mezuk said.
There are two main ways that medications may influence bone health, "first, by directly impairing bone strength, and second, by increasing the risk of falling," Dr. Mezuk said. Further research is needed to determine which of these pathways is dominant with anticonvulsants.
poster:Phillipa
thread:935375
URL: http://www.dr-bob.org/babble/20100122/msgs/935375.html