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PubMed1994

Cognitive deficits in progressive supranuclear palsy, Parkinson's disease, and multiple system atrophy in tests sensitive to frontal lobe dysfunction.

Groups of patients with idiopathic Parkinson's disease, multiple system atrophy, and progressive supranuclear palsy or Steele-Richardson-Olszewski syndrome, matched for overall clinical disability, were compared using three computerised cognitive tests previously shown to be sensitive to frontal lobe dysfunction. On a test of planning based on the Tower of London task, all three groups were impaired, but in different ways. The groups with palsy and Parkinson's disease were slower in the measure of initial thinking time, whereas the group with multiple system atrophy was only slower in a measure of thinking time subsequent to the first move, resembling patients with frontal lobe damage. On a test of spatial working memory, each group showed deficits relative to their matched control groups, but the three groups differed in their strategy for dealing with this task. On a test of attentional set shifting, each group was again impaired, mainly at the extradimensional shifting stage, but the group with Steele-Richardson-Olszewski syndrome exhibited the greatest deficit. The results are compared with previous findings in patients with Alzheimer's disease or frontal lobe damage. It is concluded that these basal ganglia disorders share a distinctive pattern of cognitive deficits on tests of frontal lobe dysfunction, but there are differences in the exact nature of the impairments, in comparison not only with frontal lobe damage but also with one another.

Aged↗

PubMed1995

Design and analysis of cancer screening trials.

This article reviews approaches to the design and analysis of cancer screening trials. After summarizing some basic screening concepts and potential pitfalls, we introduce several possible screening trial designs with examples from the literature. We review in detail methods for analyzing screening trial data, including testing for a significant difference in disease-specific mortality between the control and intervention groups, estimating the mortality differential if one exists, and evaluating the programme lead time, the screen sensitivity and the role of stage shifting. We consider Overall mortality analyses, which are based on the experience of the trial population, and Limited mortality analyses, which are based on the experience of comparable groups of cases in the control and intervention groups. We discuss methods for selecting candidate comparable case groups and confirming that they are in fact comparable. We conclude by showing how the principles discussed have been used in the planning and design of a current screening trial for multiple cancers.

Data Interpretation, Statistical↗

PubMed2005

Structure of the spontaneous all night sleep in epileptics with polysomnography.

Twenty epileptics and 11 healthy controls were investigated with polysomnography. Epileptics with interictal discharges had significantly longer total recording time and longer REM latency than the controls (P<0.05). Epileptics had a more fragmentized sleep than controls. Sleep efficiency of patients with interictal discharges was lower than that of patients without them (P<0.05). Among the patients with interictal discharges, those with partial seizures had a significantly higher arousal number than those with generalized seizures (P<0.05). The number of NREM stage shifts in patients with partial seizures tended to be higher than in those with generalized seizures.

Adult↗

PubMed2003

Toward a better understanding of the comparatively high prostate cancer incidence rates in Utah.

BACKGROUND: This study assesses whether comparatively high prostate cancer incidence rates among white men in Utah represent higher rates among members of the Church of Jesus Christ of Latter-day Saints (LDS or Mormons), who comprise about 70% of the state's male population, and considers the potential influence screening has on these rates. METHODS: Analyses are based on 14,693 histologically confirmed invasive prostate cancer cases among men aged 50 years and older identified through the Utah Cancer Registry between 1985 and 1999. Cancer records were linked to LDS Church membership records to determine LDS status. Poisson regression was used to derive rate ratios of LDS to nonLDS prostate cancer incidence, adjusted for age, disease stage, calendar time, and incidental detection. RESULTS: LDS men had a 31% (95% confidence interval, 26%-36%) higher incidence rate of prostate cancer than nonLDS men during the study period. Rates were consistently higher among LDS men over time (118% in 1985-88, 20% in 1989-92, 15% in 1993-1996, and 13% in 1997-99); age (13% in ages 50-59, 48% in ages 60-69, 28% in ages 70-79, and 16% in ages 80 and older); and stage (36% in local/regional and 17% in unstaged). An age- and stage-shift was observed for both LDS and nonLDS men, although more pronounced among LDS men. CONCLUSIONS: Comparatively high prostate cancer incidence rates among LDS men in Utah are explained, at least in part, by more aggressive screening among these men.

Aged↗

PubMed2004

Parasomnias and sleep disordered breathing in Caucasian and Hispanic children - the Tucson children's assessment of sleep apnea study.

BACKGROUND: Recent studies in children have demonstrated that frequent occurrence of parasomnias is related to increased sleep disruption, mental disorders, physical harm, sleep disordered breathing, and parental duress. Although there have been several cross-sectional and clinical studies of parasomnias in children, there have been no large, population-based studies using full polysomnography to examine the association between parasomnias and sleep disordered breathing. The Tucson Children's Assessment of Sleep Apnea study is a community-based cohort study designed to investigate the prevalence and correlates of objectively measured sleep disordered breathing (SDB) in pre-adolescent children six to 11 years of age. This paper characterizes the relationships between parasomnias and SDB with its associated symptoms in these children. METHODS: Parents completed questionnaires pertaining to their child's sleep habits. Children had various physiological measurements completed and then were connected to the Compumedics PS-2 sleep recording system for full, unattended polysomnography in the home. A total of 480 unattended home polysomnograms were completed on a sample that was 50% female, 42.3% Hispanic, and 52.9% between the ages of six and eight years. RESULTS: Children with a Respiratory Disturbance Index of one or greater were more likely to have sleep walking (7.0% versus 2.5%, p < 0.02), sleep talking (18.3% versus 9.0%, p < 0.006), and enuresis (11.3% versus 6.3%, p < 0.08) than children with an Respiratory Disturbance Index of less than one. A higher prevalence of other sleep disturbances as well as learning problems was observed in children with parasomnia. Those with parasomnias associated with arousal were observed to have increased number of stage shifts. Small alterations in sleep architecture were found in those with enuresis. CONCLUSIONS: In this population-based cohort study, pre-adolescent school-aged children with SDB experienced more parasomnias than those without SDB. Parasomnias were associated with a higher prevalence of other sleep disturbances and learning problems. Clinical evaluation of children with parasomnias should include consideration of SDB.

Arizona↗

PubMed2004

Early detection of disease and scheduling of screening examinations.

Special examinations exist for many chronic diseases, which can diagnose the disease while it is asymptomatic, with no signs or symptoms. The earlier detection of disease may lead to more cures or longer survival. This possibility has led to public health programs which recommend populations to have periodic screening examinations for detecting specific chronic diseases, for example, cancer, diabetes, cardiovascular disease and so on. Such examination schedules when embedded in a public health program are invariably costly and are ordinarily not chosen on the basis of possible trade-offs in costs and benefits for different screening schedules. The possible candidate number of examination schedules is so large that it is not feasible to carry out clinical trials to compare different schedules. Instead, this problem can be investigated by developing a theoretical model which can predict the eventual disease specific mortality for different examination schedules. We have developed such a model. It is a stochastic model which assumes that i) the natural history of the disease is progressive and ii) any benefit from earlier diagnosis is due to a change in the distribution of disease stages at diagnosis (stage shift). The model is general and can be applied to any chronic disease which satisfies our two basic assumptions. We discuss the basic ideas of schedule sensitivity and lifetime schedule sensitivity and its relation to the reduction in disease specific mortality. Our theory is illustrated by applications to breast cancer screening. The investigation of schedules compares not only examination schedules with equal intervals between examinations but also staggered schedules using the threshold method. (Examinations are carried out when an individual's risk status reaches a preassigned threshold value.).

Adult↗

PubMed1995

Effects of traffic noise on sleep: a review.

Examination of the effect of noise on sleep indicated the following: 1) Views differ on habituation to noise. 2) REM sleep in all-night sleep decreases with exposure to noise. The probability of transient changes of REM sleep to other stages is low. REM sleep induction may be disturbed by noise exposure, but once it has been induced, changes to other stages or waking occur only to a small extent. 3) A transient decrease in sleep spindles is caused by noise exposure, but the number of sleep spindles for all-night sleep increases. Sleep disturbance by noise is compensated for by an increase in sleep spindles during periods of silence, possibly indicating sleep maintenance. 4) Under certain circumstances, subjective sleep is a better indicator of the effects of noise on sleep than objective sleep parameters determined by sleep polygraphy. 5) There is a linear dose-response relationship between the peak noise level and the rate of stage shift or waking. The threshold of the noise effect is about 40 dBA.

Humans↗

PubMed2003

Effect of acute exposure to loud occupational noise during daytime on the nocturnal sleep architecture, heart rate, and cortisol secretion in healthy volunteers.

OBJECTIVES: Noise is one of the commonest physical stressors to which industrial workers are exposed. Many workers complain of symptoms associated with a non-specific generalized stress response, including disturbed sleep. However, industrial workers may be exposed to more than one source of stress and it is not possible to completely attribute the disturbed nocturnal sleep and changes in heart rate to the effects of loud noise alone. This study was done to find out whether acute exposure of healthy individuals to loud occupational noise during the daytime would cause changes in their nocturnal sleep architecture, heart rate during sleep and serum cortisol levels. METHODS: Baseline polysomnography was done on ten subjects who were exposed for eight hours either to continuous occupational background noise levels of >75dB(A), or a quiet environment. Sleep polysomnography was done on the night prior to and after exposure. Blood was collected for serum cortisol estimation at night prior to sleep and in the morning after waking up. Statistical analysis was done by repeated measures ANOVA with Tukey's post test. RESULTS: The sleep efficiency was less than 80% and the total time spent in Rapid Eye Movement (REM) sleep, Slow Wave Sleep (SWS) and the REM onset latency were significantly decreased on the night after exposure to noise. There was a significant increase in stage shifts. The percentage fall in heart rate during sleep was decreased compared to the baseline values. The serum cortisol levels in the morning after exposure to noise was significantly increased. CONCLUSION: Workers exposed to loud background occupational noise react to the stress and show changes in nocturnal sleep architecture and heart rate which may be contributed to the exposure to noise.

Adolescent↗

PubMed1981

Dual activity patterns of fast pyramidal tract cells and their family neurones during EEG arousal in the cat.

1. Intracellular activities of fast pyramidal tract (PT) cells and their family neurones were investigated during the EEG arousal of various degrees in terms of (1) the strength of natural or midbrain reticular stimuli, (2) the length of aroused EEG and (3) the extent of stage shift from EEG synchronization to desynchronization. 2. These cells showed a response pattern of either disfacilitation (DF), disfacilitation followed by excitation (DF + E) or excitation (E). DF and E components in these responses were respectively quantified with their amplitude and incidence, and their relations to the above-listed intensity parameters of EEG arousal were examined. 3. The threshold of eliciting DF response was lower than that for E response to natural and reticular stimuli. On intensifying the parameters of EEG arousal, accompanying increases were observed in E response but not in DF response. Rather, DF response was often masked by E response on application of relatively intense stimuli, or was decreased in a reciprocal manner to the increase of E response in accordance with the degree of EEG arousal. 4. It is postulated that the phasic and tonic phases of EEG arousal manifested, respectively, as the initial DF and late E responses bear different functions, the former representing the cerebral state of a general set on receipt of a novel stimulus, and the latter involving the state of actively responding to the stimulus by encoding its intensity.

Animals↗

PubMed2004

Screening for lung cancer--a review.

Despite recent advances in oncology lung cancer remains the most common cause of cancer death in the United States, and its cure rate has not improved for the past 20 years. Lung cancer has been a target for numerous screening strategies, aimed at its earlier detection, and potentially improved cure. We describe the research grounds for screening for malignancies, including types of bias inherent to screening trials and present a brief discussion of potential outcomes of screening. We then discuss the results of trials of chest radiography and sputum analysis. We then comment on the recent and on-going research of computed tomography (CT) screening for lung cancer. Computed tomography offers many advantages over routine radiographs in screening for lung cancer. Recent data indicate an impressive stage shift and improved resectability of lung cancers detected by the CT. Large-scale studies with longer periods of follow-up will show whether these promising results will translate into an improved lung cancer-related mortality in the screened population.

Bias↗

PubMed1990

Fluoxetine in major depression: efficacy, safety and effects on sleep polygraphic variables.

Fluoxetine (60 mg), a selective inhibitor of the reuptake of 5-HT, was compared in a double-blind trial to amitriptyline (150 mg) in a sample of 34 patients fitting the Research Diagnostic Criteria for a major depressive disorder. Patients were studied after a drug washout period of 10 days and an active treatment period of 42 days. Sleep polygraphic recordings were performed before and at the end of the study. As indicated by the significant decrease in the Hamilton Depression scale and the Montgomery Asberg Depression scale, fluoxetine showed similar antidepressant effects to amitriptyline with significantly fewer adverse effects. Fluoxetine and amitriptyline decreased the amount of REM sleep, a well known effect of classical antidepressants. Fluoxetine showed some specific effects on sleep continuity (potentially dose related) as indicated by the significant increase in the number of awakenings and in stage shifts, without interfering with the therapeutic response.

Adolescent↗

PubMed1990

Statistical considerations in cancer screening programs.

The goal of cancer screening is the early detection and treatment of disease, with a consequent reduction in the mortality rate. Evaluation of whether a particular screening program can achieve this goal is a difficult task. Two components of the screening process must be assessed. The first is the ability of the screening test to detect cancer early while minimizing the number of false-positive results. In this regard, the specificity of the test ordinarily must be very high, approaching 99%. No screening test for prostate cancer has yet been reported to have a specificity this high, indicating that any prostate cancer screening program using currently available tests will have to deal with the problem of a large number of false-positive findings. To evaluate the overall impact of a screening program, the best procedure is the randomized controlled trial with cancer-specific mortality as the endpoint. This endpoint is used because it avoids the lead time and length biases inherent in other outcome variables such as stage shift and case survival. The screening randomized controlled trial must be carefully planned and implemented, because it is lengthier and more costly than the usual therapy trial because of differences in study populations, trial design relative to the planned population intervention, and the extent of knowledge of disease natural history. A further important component of screening evaluation is cost. The decision to implement or continue a screening program can be aided by using cost-effectiveness analysis, which bases a decision on the ranking of cost-to-benefit ratios for the various programs contending for limited funds. Screening cost includes the cost of the test, the cost of side effects of the test, and the costs of biopsy and treatment, while screening benefit can be measured in terms of lives saved, life years saved, or quality-adjusted life years.

Cost-Benefit Analysis↗

PubMed1995

Clinical evaluation of lansoprazole in the treatment of peptic ulcers: initial healing and prevention of relapse. Tohoku Peptic Ulcer Study Group.

The clinical usefulness of lansoprazole in the healing of gastric and duodenal ulcers, the S2-stage shift rate (white scarring rate), and endoscopic healing rate with respect to degree of gastric mucosal atrophy were investigated. The subjects were 50 gastric ulcer and 37 duodenal ulcer patients. The endoscopic healing rate in patients with gastric ulcers after initial treatment with lansoprazole was 92% after 8 weeks. The S2-shift rate was 38% after 8 weeks. The 8-week healing rate in patients without atrophy was 100% and with atrophy was 92%, although the difference was not statistically significant. The S2-shift rate in patients without atrophy was 42% and in patients with atrophy was slightly lower, at 37%, although the difference was not statistically significant. The endoscopic healing rate in patients with duodenal ulcers was 93% after 6 weeks, and the S2-shift rate was 59%. It is firmly established that atrophic gastric mucosa shows a reduction in mucosal defense factors. However, lansoprazole achieved good endoscopic healing rates and S2-shift rates even in patients with gastric ulcers with atrophic background mucosa.

2-Pyridinylmethylsulfinylbenzimidazoles↗

PubMedDate not supplied

Rapid rise and subsequent decline in prostate cancer incidence rates for New Mexico, 1989-1993.

Beginning in the late 1980s, a large increase in incidence rates for prostate cancer occurred in association with increased prostate-specific antigen (PSA) screening. In New Mexico, the increased screening was associated with earlier detection of cancers and decreased prostate cancer mortality, suggesting that PSA screening may be effective. PSA screening has become a controversial topic of public debate, and anecdotal reports from physicians indicated that prostate cancer screening practice patterns were changing in New Mexico. To assess whether PSA-associated trends in prostate cancer incidence were continuing, we examined incidence rates from 1989 to 1993 among men in New Mexico. From 1989 to 1992, age-adjusted rates increased substantially for non-Hispanic whites (77%), Hispanics (50%), and American Indians (27%). Although rates increased for all stages combined, incidence rates decreased for distant-stage disease, especially for non-Hispanic whites, indicating a continuing trend toward earlier detection. In 1993, incidence rates unexpectedly decreased from 203 to 158/100,000 in non-Hispanic whites, largely as a result of changes in rates in men over age 65 years. Although incidence rates decreased, the trend toward earlier detection was maintained for non-Hispanic whites. In contrast, among Hispanic and American Indians, rates did not change substantially between 1992 and 1993. Because the epidemic in prostate cancer was associated with increased PSA screening, it is likely that the trends for non-Hispanic whites are also related to PSA screening. We suggest that the decrease in rates and the continued stage shift are consistent with repeated screening of men in the population at risk.

Aged↗

PubMed1998

[Alertness disorders and parasomnias of the wakefulness-sleep transition].

INTRODUCTION: Disorders of arousal and parasomnias of sleep-wake transition are revisited. Disorders of arousal are: Sleepwalking (SW), confusional arousals (CA) and sleep terrors (ST). SW, CA and ST are different clinical manifestations of the same disorder being ST the most severe and SW the mildest manifestation. Disorders of arousal are typical parasomnias of NREM sleep, mainly slow wave sleep. Pathophysiological mechanism of these disorders is the state's dissociation of wakefulness and sleep. The conjunction of the constitutional factors (genetic, age, sleep privation, drugs, psychological, etc.), and precipitant factors (light, sound, temperature, touch, apnea, gastroesophageal reflux, seizure, fever, psychological, etc.) permit three possible arousal behavioral response: A full awakening, a shift stage of sleep or a partial arousal. Clinical significance of arousal parasomnias depend on the age. In children are caused by developmental and genetic factors and usually are autolimited. In adults usually are caused by psychopathology. In the elderly are often caused by organic brain syndromes. Parasomnias of sleep-wake transition are: Rhythmic movements of sleep, sleeptalking, starts and the nocturnal cramp. Most of them are mild disorders, almost physiological phenomena that usually don't need any treatment.

Adult↗

PubMed1998

Sleep fragmentation in children with juvenile rheumatoid arthritis.

OBJECTIVE: To characterize sleep patterns of patients with juvenile rheumatoid arthritis (JRA). METHODS: Sixteen patients with JRA aged 12+/-4 years and 9 controls aged 11+/-3 years underwent a comprehensive evaluation by self-report questionnaire and formal all night polysomnographic recordings. Multiple sleep latency test was performed in 7 patients. RESULTS: Patients had 90% more arousals and awakenings (p<0.01) and the median length of occurrences of uninterrupted sleep in stages 2 and 3 and rapid eye movement (REM) sleep was 60% shorter than in controls (p<0.01). The overall amount of sleep stage shift from deeper to lighter sleep was 23.5+/-10.8 events in patients compared to 14.9+/-4.0 in controls (p<0.05). In 15 of 16 patients 15% of non-REM sleep consisted of alpha-delta (alpha-rating) sleep, compared with less than 1% in controls (p<0.001). Multiple sleep latency test for patients was 10.3+/-2.6 min. There were no differences between JRA and controls in self-reported questions. However, patients reported longer afternoon naps, 1.8+/-1.3 h compared to 0.3+/-0.8 h in controls (p<0.05). CONCLUSION: Objective polysomnographic evidence of abnormal sleep has been confirmed in patients with JRA. Sleep disturbance was associated with daytime sleepiness as evidenced by abnormal multiple sleep latency test and longer afternoon naptime.

Adolescent↗

PubMed2003

Longitudinal shifts in exercise stages of change in college students.

AIM: The protective health benefits of regular physical activity are well established. To date, few studies have assessed the prevalence of exercise behavior and factors influencing exercise adoption and maintenance among college students. The purpose of this study was to examine the relationship of exercise self-efficacy, social support, and sedentary behavior and longitudinal shifts in stage of exercise behavior change among a sample of college students without intervention. METHODS: A cross-sectional design was used to examine demographic characteristics, stage of exercise behavior change, exercise self-efficacy, social support (family and friend) and sedentary behavior. One hundred and sixty-one students at a large Midwestern university completed a valid and reliable written mailed questionnaire during baseline assessment and again 6 months later (follow-up). RESULTS: Changes in exercise self-efficacy, social support, and sedentary behavior were not observed among students who maintained their stage of exercise behavior change from baseline to follow-up. Exercise relapsers experienced significant decreases in exercise self-efficacy and peer social support from baseline to follow-up. CONCLUSION: These findings have important implications for further research on exercise adoption and maintenance among college students. From an applied perspective, it would be valuable for the practitioner to understand that different predictors are likely to influence exercise adoption and relapse.

Adult↗

PubMed2000

Mycobacterium bovis bacillus calmette-guérin induces protective immunity against infection by Plasmodium yoelii at blood-stage depending on shifting immunity toward Th1 type and inducing protective IgG2a after the parasite infection.

Bacillus calmette-guérin (BCG)-vaccination raised dramatically the survival rates of A/J mice from infection by Plasmodium yoelii 17XL at blood-stage. The analysis of the immune response of spleen cells indicated that BCG vaccination biased the immune response toward Th1 type. Neutralization of IFN-gamma and nitric oxide abrogated the protection. The kinetics of Ab production in the course of P. yoelii 17XL infection was monitored. Surprisingly, larger amounts of parasite-specific Abs were produced in BCG-vaccinated mice than in the placebo control. The vast majority of the produced IgG against parasites in BCG-vaccinated mice was IgG2a, which was observed hardly in placebo controls. The peak of IgG2a production coincided with the clearance of infection. The naive mice transferred adoptively with IgG2a from self-cured mice survived the lethal challenge from the parasite. These data indicated that BCG vaccination protected A/J mouse from P. yoelii 17XL infection by biasing immunity toward Th1-type after parasite infection and enhancing production of IgG2a, which ultimately played a major role in protection.

Animals↗