Occupational exposures and amyotrophic lateral sclerosis. A population-based case-control study

This population-based case-control study was conducted in three countries in western Washington State to evaluate associations between workplace exposures and the risk of amyotrophic lateral sclerosis (ALS). Cases (n = 174) were all newly diagnosed with ALS by neurologists during 1990-1994, and controls (n = 348), who were matched according to age (+/-5 years) and sex, were identified via random-digit dialing or Medicare enrollment files. Four industrial hygienists blindly assessed detailed lifetime job histories for exposures to metals, solvents, and agricultural chemicals. Case-control comparisons were made for jobs held between 15 years of age and 10 years prior to the cases' dates of diagnosis. After adjustment for age and education, ever exposure to agricultural chemicals was associated with ALS (odds ratio (OR) = 2.0, 95% confidence interval (CI) 1.1-3.5); this association was observed separately in men (OR = 2.4, 95% CI 1.2-4.8) but not in women (OR = 0.9, 95% CI 0.2-3.8). Among men, the odds ratio for low exposure to agricultural chemicals (below the median level for exposed controls) relative to no exposure was 1.5 (95% CI 0.4-5.3), and for high exposure, it was 2.8 (95% CI 1.3-6.1) (p for trend = 0.03). Similar analyses based on the panel's assessment of exposures to metals and solvents showed no associations. These findings suggest an association between ALS and agricultural chemicals in men.     

Stroke and use of low-dose oral contraceptives in young women: a pooled analysis of two US studies

BACKGROUND AND PURPOSE: The available data on low-dose oral contraceptive pill (OCP) use and stroke risk in US women are limited by small numbers. We sought more precise estimates by conducting a pooled analysis of data from 2 US population-based case-control studies. METHODS: We analyzed interview data from 175 ischemic stroke cases, 198 hemorrhagic stroke cases, and 1191 control subjects 18 to 44 years of age. RESULTS: For ischemic stroke, the pooled odds ratio (pOR) adjusted for stroke risk factors for current use of low-dose OCPs compared with women who had never used OCP (never users) was 0.66 (95% confidence interval [CI], 0.29 to 1.47) and compared with women not currently using OCPs (nonusers) the pOR was 1.09 (95% CI, 0.54 to 2.21). For hemorrhagic stroke, the pOR for current use of low-dose OCPs compared with never users was 0.95 (95% CI, 0.46 to 1.93) and compared with nonusers the pOR was 1.11 (95% CI, 0.61 to 2.01). The pORs for current low-dose OCP use and either stroke type were not elevated among women who were >/=35 years, cigarette smokers, obese, or not receiving medical therapy for hypertension. pORs for current low-dose OCP use were 2.08 (95% CI, 1. 19 to 3.65) for ischemic stroke and 2.15 (95% CI, 0.85 to 5.45) for hemorrhagic stroke among women reporting a history of migraine but were not elevated among women without such a history. Past OCP use (irrespective of formulation) was inversely related to ischemic stroke but unrelated to hemorrhagic stroke. CONCLUSIONS: Women who use low-dose OCPs are, in the aggregate, not at increased risk of stroke. Studies are needed to clarify the risk of stroke among users who may be susceptible on the basis of age, smoking, obesity, hypertension, or migraine history.     

A comment on "Race, IQ, and the middle class" by Trotman: Rampant false conclusions.

In a recent article, F. K. Trotman (see record 1978-06591-001) obtained parental responses to a childrearing interview in Black and White samples and correlated the responses with the achievement and intelligence indexes of the children. The correlations were quite high, making it clear that adjustment for racial differences in parental responses would all but remove racial differences in achievement and intelligence of the children. Trotman makes several erroneous conclusions on the basis of this result, and the present author points out these conclusions. In particular, it is shown how Trotman's study says nothing important about the nature–nurture issue as it applies to racial differences in intelligence. (11 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Resolution of serum and cerebrospinal fluid abnormalities after treatment of neurosyphilis. Influence of concomitant human immunodeficiency virus infection

BACKGROUND AND OBJECTIVES: Little is known about resolution of serum and cerebrospinal fluid abnormalities after neurosyphilis treatment, especially in patients infected with human immunodeficiency virus (HIV). GOAL: To examine the time course of resolution of these abnormalities. STUDY DESIGN: Case series of 22 patients with neurosyphilis (13 infected with HIV) with reactive cerebrospinal fluid Venereal Disease Research Laboratory test who underwent at least one lumbar puncture after treatment. RESULTS: Resolution of all serum and cerebrospinal fluid measures was slower in patients infected with HIV. Serum and cerebrospinal fluid abnormalities resolved in most patients not infected with HIV by 30 weeks, and all met Centers for Disease Control and Prevention criteria for cure. One patient infected with HIV failed therapy by Centers for Disease Control and Prevention criteria, and three others had persistent pleocytosis. CONCLUSIONS: HIV-infected patients with neurosyphilis have slower resolution of serum and cerebrospinal fluid abnormalities after therapy. This observation may suggest impaired clearance of Treponema pallidum from the central nervous system.     

Revisiting Skeels' final study: A critique.

Reviews H. M. Skeels's (see record 1966-13077-001) study on the effect of early environment on intelligence. Although such findings are often regarded as irrefutable, a reexamination of the supposed decrement in intelligence in the contrast group and the supposed increment in the intelligence in the treatment group led the author to disagree. It is concluded that the study is riddled and confounded with variables that make a clear interpretation of the results impossible. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Reasoning and secondary reinforcement in 6–7-year-olds and 10–11-year-olds.

Conducted 2 experiments to investigate the 1st author's cognitive theory of secondary reinforcement effects, which predicts that Ss of a preoperational age (i.e., younger than 7 yrs) should not necessarily learn responses followed by a stimulus object previously instrumental in obtaining a reward, while Ss of a postoperational age should do so. Using 24 1st and 24 5th graders in 2 learning tasks, the prediction was confirmed. Furthermore, verbal responses indicated that the logical operations that presumably influenced the behavior of the older children actually did occur. In Exp II, using 28 2nd and 15 6th graders, the training task was simplified in order to try to facilitate logical reasoning, but the behavior of the younger Ss was not affected. It is concluded that secondary reinforcement of a stimulus–response associative type has yet to be demonstrated, and that secondary reinforcement of a cognitive type is heavily dependent on reasoning ability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Intravenous glucose after out-of-hospital cardiopulmonary arrest: a community-based randomized trial

Question: Does the common practice of infusing small amounts of glucose after cardiopulmonary arrest worsen neurologic outcome? Design and setting: A community-based randomized trial in Seattle, WA. Paramedics treated all patients with out-of-hospital cardiac arrest in a standard fashion except that the intravenous infusion did or did not contain glucose; ie, patients received either usual treatment, with 5% dextrose in water (D5W), or alternative, with half normal saline (0.45S). Outcomes: The main outcome was awakening, defined as the patient having comprehensible speech or following commands as determined by chart review. Other outcomes were survival to hospital admission and to discharge. Results: Over 2 years, paramedics randomized 748 patients. The type of fluid administered was not significantly related to awakening (16.7% for D5W versus 14.6% for 0.45S), admission (38.0% for D5W versus 39.8% for 0.45S), or discharge (15.1% for D5W versus 13.3% for 0.45S). As in previous studies, patients whose arrest had likely been on a cardiac basis with initial rhythms of ventricular fibrillation or asystole had admission blood glucose levels significantly related to awakening: mean = 309 mg/dl for never awakening and 251 mg/dl for awakening. Of note, the relation between glucose and awakening was reversed in the remaining patients, who had electromechanical dissociation or noncardiac mechanisms of arrest. Conclusion: Current practices of using limited amounts of glucose-containing solutions after cardiopulmonary arrest do not need to be changed. Blood glucose level on admission is a prognostic indicator but depends on the type of arrest.     

Exceptions to Hick's law: Explorations with a response duration measure.

Conducted 5 experiments with 113 undergraduates, in which a new response-duration measure was used to explore the conditions necessary for confirmation of Hick's law, which states that reaction time (RT) increases logarithmically with number of choices. Exceptions to the law include the following conditions: a verbal response, a familiar stimulus with a single dominant name, and a large number of practice trials. These conditions have previously been used to account for the anamolous results. The present studies used none of these conditions and yet managed to replicate the anamolous result of a shallow slope across set size by using a novel task, in which the initial component of the response was the same for all stimuli (depression of a single response key) but the termination was different (different durations for each stimulus). Using this task, a slope of 15 msec per bit of stimulus uncertainty was found, as compared with the usual value of about 150 msec. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)