Effects of FDA Advisories on the Pharmacologic Treatment of ADHD, 2004–2008

This study assessed the effect of public health advisories issued between 2005 and 2007 by the U.S. Food and Drug Administration (FDA) on treatments of attention-deficit hyperactivity disorder (ADHD) and physician prescribing practices

Neuronal sensitivity to TDP-43 overexpression is dependent on timing of induction

Ubiquitin-immunoreactive neuronal inclusions composed of TAR DNA binding protein of 43 kDa (TDP-43) are a major pathological feature of frontotemporal lobar degeneration (FTLD-TDP). In vivo studies with TDP-43 knockout mice have suggested that TDP-43 plays a critical, although undefined role in development. In the current report, we generated transgenic mice that conditionally express wild-type human TDP-43 (hTDP-43) in the forebrain and established a paradigm to examine the sensitivity of neurons to TDP-43 overexpression at different developmental stages. Continuous TDP-43 expression during early neuronal development produced a complex phenotype, including aggregation of phospho-TDP-43, increased ubiquitin immunoreactivity, mitochondrial abnormalities, neurodegeneration and early lethality. In contrast, later induction of hTDP-43 in the forebrain of weaned mice prevented early death and mitochondrial abnormalities while yielding salient features of FTLD-TDP, including progressive neurodegeneration and ubiquitinated, phospho-TDP-43 neuronal cytoplasmic inclusions. These results suggest that neurons in the developing forebrain are extremely sensitive to TDP-43 overexpression and that timing of TDP-43 overexpression in transgenic mice must be considered when distinguishing normal roles of TDP-43, particularly as they relate to development, from its pathogenic role in FTLD-TDP and other TDP-43 proteinopathies. Finally, our adult induction of hTDP-43 strategy provides a mouse model that develops critical pathological features that are directly relevant for human TDP-43 proteinopathies

Effects of FDA Advisories on the Pharmacologic Treatment of ADHD, 2004–2008

OBJECTIVE: This study assessed the effect of public health advisories issued between 2005 and 2007 by the U.S. Food and Drug Administration (FDA) on treatments of attention-deficit hyperactivity disorder (ADHD) and physician prescribing practices. METHODS: Data obtained from the IMS Health National Disease and Therapeutic Index, a nationally representative audit of ambulatory physicians, were used to examine trends in office visits by children and adolescents (under age 18) during which ADHD was treated with Adderall, other psychostimulants, or atomoxetine. Segmented time series regressions were conducted to determine changes in use associated with three advisories issued between 2005 and 2007. RESULTS: In 2004, before the first FDA advisory, Adderall accounted for 36% of ADHD pharmacotherapy treatment visits. Other stimulants accounted for 46%, and atomoxetine accounted for 19%. Overall pharmacotherapy treatment rates were stable over the study period, but by 2008 the treatment visits accounted for by Adderall (that is, market share) declined to 24%, and the market share for atomoxetine declined to 8%. The market share for substitute therapies—clonidine, guanfacine, and bupropion—was stable over this period, ranging from 5% to 7%. Despite the declines in the use of Adderall and atomoxetine over the study period, results from the regression models suggest that the advisories did not have a statistically significant effect on ADHD medication prescribing. CONCLUSIONS: FDA advisories regarding potential cardiovascular and other risks of ADHD medications had little discernible incremental effect on the use of these medicines in this nationally representative ambulatory audit