Menstrual phase as predictor of outcome after mild traumatic brain injury in women.

OBJECTIVE: To determine whether menstrual cycle phase in women at the time of mild traumatic brain injury (mTBI) predicts 1-month outcomes. SETTING: Six emergency departments; 5 in Upstate New York, and 1 in Pennsylvania. PARTICIPANTS: One hundred forty-four female participants (age, 16-60) who presented to participating emergency departments within 4 hours of mTBI. DESIGN: Nested cohort study with neurologic and quality-of-life outcome assessment, 1 month after enrollment. Female subjects aged 16 to 60 enrolled in the parent cohort study, with 1-month neurological determination data available, were classified into menstrual cycle groups by serum progesterone concentration and self-reported contraceptive use. MAIN MEASURES: Rivermead Post Concussion Questionnaire and EuroQoL/EQ5D. RESULTS: Women injured during the luteal phase of their menstrual cycle, when progesterone concentration is high, had significantly lower EuroQoL General Health Ratings and Index Scores than women injured during the follicular phase of their cycle or women taking oral contraceptives. Multivariate analysis confirmed a significant independent effect of menstrual cycle phase on EuroQoL Index Score and the Rivermead Post Concussion Questionnaire Somatic Subscore. CONCLUSION: Menstrual cycle phase and progesterone concentration at the time of mTBI affect 1-month quality-of-life and neurologic outcomes. This association has important implications for treatment and prognosis after mTBI.

Parkinson's disease: evidence for environmental risk factors.

Parkinson's disease (PD) has no known cause. Although recent research has focused particularly on genetic causes of PD, environmental causes also play a role in developing the disease. This article reviews environmental factors that may increase the risk of PD, as well as the evidence behind those factors. Enough evidence exists to suggest that age has a causal relationship to PD. Significant evidence exists that gender, tobacco use, and caffeine consumption are also associated with the development of PD. Other environmental factors (pesticide exposure, occupation, blood urate levels, NSAID use, brain injury, and exercise) have limited or conflicting evidence of a relationship to PD. Future research must not neglect the impact of these environmental factors on the development of PD, especially with respect to potential gene-environment interactions.

Milestones in movement disorders clinical trials: advances and landmark studies.

Over the past 25 years clinical trials testing in movement disorders has evolved in order to more effectively and efficiently analyze the safety and efficacy of new interventions. Studies today regularly incorporate methods to decrease placebo and bias effects and to ensure more rigorous statistical analyses. Newer, standardized, and validated rating scales such as the Unified Parkinson's Disease Rating Scale and the Unified Huntington's Disease Rating Scale are routinely employed in an effort to produce results that are comparable across different sites and studies. Several landmark studies in movement disorder research highlight these and other prominent procedural advances. The Deprenyl and Tocopherol Antioxidative Therapy of Parkinsonism trial pioneered the use of functional clinical end points, utilized a 2 × 2 factorial design to more efficiently analyze multiple interventions, and employed a washout design to assist in sorting putative neuroprotective from symptomatic effects. PRECEPT included neuroimaging as an outcome measure and highlighted the importance of futility studies in more efficiently directing resources. TEMPO and ADAGIO introduced the use of delayed-start (or 2-period) trials to try to identify disease-modifying interventions. NET-PD used futility studies to streamline the evaluation of potentially valuable treatments, followed by a large, long-term simple study design to assess the clinical significance of a new intervention. There have also been advances in clinical trials testing new surgical interventions, with the introduction of blinded outcome assessments and sham-surgery control groups. Collectively, methodological advances in clinical trials have permitted the safety and efficacy of new interventions to be tested more efficiently and economically and with a higher level of certainty that the potential benefits and adverse effects of interventions recommended for general use are well understood.