Times to Discontinue Antidepressants Over 6 Months in Patients with Major Depressive Disorder.

OBJECTIVE: The aim of the present study was to investigate differences in discontinuation time among antidepressants and total antidepressant discontinuation rate of patients with depression over a 6 month period in a naturalistic treatment setting. METHODS: We reviewed the medical records of 900 patients with major depressive disorder who were initially prescribed only one kind of antidepressant. The prescribed antidepressants and the reasons for discontinuation were surveyed at baseline and every 4 weeks during the 24 week study. We investigated the discontinuation rate and the mean time to discontinuation among six antidepressants groups. RESULTS: Mean and median overall discontinuation times were 13.8 and 12 weeks, respectively. Sertraline and escitalopram had longer discontinuation times than that of fluoxetine, and patients who used sertraline discontinued use significantly later than those taking mirtazapine. No differences in discontinuation rate were observed after 24 weeks among these antidepressants. About 73% of patients discontinued antidepressant treatment after 24 weeks. CONCLUSION: Sertraline and escitalopram tended to have longer mean times to discontinuation, although no difference in discontinuation rate was detected between antidepressants after 24 weeks. About three-quarters of patients discontinued antidepressant maintenance therapy after 24 weeks.

Effect of increased axial rotation angle on bone mineral density measurements of the lumbar spine.

BACKGROUND CONTEXT: Osteoporosis frequently occurs in elderly people and is commonly associated with neuromuscular diseases or severe cerebral palsy. Osteoporosis can cause pain via compression fractures or secondary neurologic deficits; thus, accurate evaluation of bone mineral density (BMD) is essential for the prevention and treatment of osteoporosis. However, spinal axial rotation caused by scoliosis may affect the outcome of BMD tests, such that BMD measurements may be significantly greater than actual BMD in patients with severe scoliosis of the spine. PURPOSE: We investigated the effect of axial rotation angle on BMD measurements of the phantom spine. STUDY DESIGN/SETTING: Investigation for the effect of axial rotation with aluminum phantom spine. METHODS: A GE-Lunar Aluminum Spine Phantom was used to assess BMD. Bone mineral content (BMC), BMD, and cross-sectional area were measured 100 times at L1-L4 using a GE Lunar Prodigy Vision system. Dual-energy X-ray absorptiometry was performed at axial rotation angles of 0° to 25° (5° intervals). RESULTS: Cross-sectional area decreased and BMD values increased as the axial rotation angle increased, whereas BMC did not change significantly. A fitting function was obtained to evaluate the relationships among axial rotation angle, cross-sectional area, and BMD. We obtained an equation to estimate BMD at L1-L4: 1.000-0.001674x+0.0001043x(2)-0.000005333x(3), where x denotes the axial rotation angle. We found that the observed BMD needed adjustment when the angle was more than 5°. CONCLUSIONS: Bone mineral density values may be overestimated in patients with even slight (>5°) axial rotation. When osteoporosis is suspected in a clinical setting, the degree of axial rotation should be measured on a lumbar spine X-ray.

Clinical application of gamma knife dose verification method in multiple brain tumors : modified variable ellipsoid modeling technique.

OBJECTIVE: The Leksell Gamma Knife® (LGK) is based on a single-fraction high dose treatment strategy. Therefore, independent verification of the Leksell GammaPlan® (LGP) is important for ensuring patient safety and minimizing the risk of treatment errors. Although several verification techniques have been previously developed and reported, no method has ever been tested statistically on multiple LGK target treatments. The purpose of this study was to perform and to evaluate the accuracy of a verification method (modified variable ellipsoid modeling technique, MVEMT) for multiple target treatments. METHODS: A total of 500 locations in 10 consecutive patients with multiple brain tumor targets were included in this study. We compared the data from an LGP planning system and MVEMT in terms of dose at random points, maximal dose points, and target volumes. All data was analyzed by t-test and the Bland-Altman plot, which are statistical methods used to compare two different measurement techniques. RESULTS: No statistical difference in dose at the 500 random points was observed between LGP and MVEMT. Differences in maximal dose ranged from -2.4% to 6.1%. An average distance of 1.6 mm between the maximal dose points was observed when comparing the two methods. CONCLUSION: Statistical analyses demonstrated that MVEMT was in excellent agreement with LGP when planning for radiosurgery involving multiple target treatments. MVEMT is a useful, independent tool for planning multiple target treatment that provides statistically identical data to that produced by LGP. Findings from the present study indicate that MVEMT can be used as a reference dose verification system for multiple tumors.