Evidence-based medicine: a new paradigm or the Emperor's new clothes?
Explore the source record for details and available documents.
Evidence-Based Medicine↗
Biomedical subjects
E Shahar
Publications and source records attributed to E Shahar.
Melatonin treatment in an institutionalised child with psychomotor retardation and an irregular sleep-wake pattern.
An institutionalised 13 year old girl with psychomotor retardation suffered from an irregular sleep-wake pattern. Multiple measurements of urinary sulphatoxy-melatonin (aMT6) concentrations were abnormally low, without any significant day-night differences. Administration of exogenous melatonin (3 mg) at 18:00 resulted in increased nocturnal urinary aMT6 concentrations and improvements in her sleep-wake pattern. Melatonin may help disabled children suffering from sleep disorders.
Adolescent↗
Correlates of cognitive function in middle-aged adults. Atherosclerosis Risk in Communities (ARIC) Study Investigators.
The Atherosclerosis Risk in Communities Study administered cognitive function tests to more than 14,000 middle-aged adults in 1990-1992. The battery included the Delayed Word Recall test, the Digit Symbol Subtest of the Wechsler Adult Intelligence Scale-Revised, and the Controlled Oral Word Association (Word Fluency) test. Test performance was correlated positively with education level, negatively with age, was better in women than in men, and better in managers/professionals compared with other occupations. After controlling for these factors, race and community, the findings most consistent for both sexes were that Delayed Word Recall was negatively associated with depressive symptoms, diabetes, and fibrinogen level; the Digit Symbol Subtest was associated with marital status, negatively associated with depressive symptoms, smoking status, fibrinogen level, and carotid intima-media thickness, and positively associated with alcohol drinking and FEV1; and the Word Fluency test was positively associated with marital status, alcohol drinking, sports participation, and FEV1. Most of these cross-sectional results were in the predicted direction and have biologic plausibility, but mean differences between extreme categories were small (generally on the order of 0.1 to 0.2 of a standard deviation). Longitudinal study is warranted to evaluate whether small differences in middle-age lead to larger, clinically meaningful deficits with aging.
Age Distribution↗
High incidence of hypoglycemic episodes with neurologic manifestations in children with insulin dependent diabetes mellitus.
UNLABELLED: Hypoglycemia is a serious frequent complication of insulin therapy in type 1 diabetes. PATIENTS AND METHODS: We surveyed 139 IDDM patients. RESULTS: Forty-four patients (32%) reported at least one severe hypoglycemic episode. All patients with severe hypoglycemia experienced neurological manifestations. Symptoms included confusion and abnormal behavior, convulsions, coma, transient hemiparesis and one case of permanent hemiparesis. Most episodes occurred at night or during morning hours. 44% of episodes were related to delayed meal or snack, 11% to excess insulin administration and 13% to extra physical activity. HbA1c was significantly lower in patients with severe hypoglycemia compared with diabetic controls (7.33 +/- 1.09% and 9.45 +/- 4.32%, respectively).
Adolescent↗
Trends in cigarette smoking: the Minnesota Heart Survey, 1980 through 1992.
OBJECTIVES: The purpose of this study was to describe trends in the prevalence of cigarette smoking between 1980 through 1982 and 1990 through 1992 in Minneapolis and St. Paul, Minn. METHODS: Three population-based surveys were conducted among adults 25 to 74 years of age in 1980 through 1982, 1985 through 1987, and 1990 through 1992. RESULTS: Overall age-adjusted prevalences of cigarette smoking declined significantly between 1980-1982 and 1985-1987 and between 1985-1987 and 1990-1992. Serum thiocyanate, a biochemical marker for tobacco use, also declined significantly over the 3 periods. CONCLUSIONS: Favorable trends in smoking prevalence and cigarette consumption among smokers were observed, but disturbing trends in some smoking behaviors were also noted.
Adult↗
Evidence-based medicine--little hope for a critical debate.
Explore the source record for details and available documents.
Evidence-Based Medicine↗
Weight-loss induced changes in plasma factor VII coagulant activity and relation to the factor VII Arg/Gln353 polymorphism in moderately obese adults.
Elevated plasma factor VII coagulant activity (factor VIIc) may be an independent risk factor for coronary heart disease. Several cross-sectional studies suggest that a polymorphism of the factor VII gene (Arg-Gln353) interacts with plasma triglyceride level in determining factor VIIc, but prospective data are lacking. Factor VII genotype, factor VIIc, and triglyceride level were measured in moderately obese adults aged 25 to 45 who underwent a six-month clinical trial to evaluate strategies for weight loss. A total of 48 men and 50 women who experienced substantial weight loss (mean: 10 kg) provided samples for genetic analysis. Overall, 78% of participants were homozygous for the Arg353 allele, while the remaining 22% were heterozygous (Arg/Gln353). At the baseline examination, heterozygotes had lower mean factor VIIc than Arg353 homozygotes (92% vs. 112%; p<0.001), and genotype explained 18% of the variance of factor VIIc. Average six-month weight loss was similar in both genotypes; mean reductions in factor VIIc following weight loss were greatest among Arg353 homozygotes with high initial values (> 120%). Cross-sectional and longitudinal associations between plasma factor VIIc and triglyceride level were not dependent on genotype. These data confirm that the Gln353 allele is associated with lower factor VII coagulant activity in moderately obese adults, but they do not support the hypothesis that the Arg-Gln353 polymorphism interacts with plasma triglyceride level in determining factor VIIc.
Adult↗
Trends in cholesterol knowledge and screening and hypercholesterolemia awareness and treatment, 1980-1992. The Minnesota Heart Survey.
BACKGROUND: National cholesterol education initiatives were implemented in the middle to late 1980s. This study examines whether there were significant increases in population cholesterol knowledge and screening and hypercholesterolemia awareness and treatment from 1980 to 1992. METHODS: Three population-based surveys were conducted among adults aged 25 to 74 years in 1980-1982 (N = 4086), 1985-1987 (N = 5735) and 1990-1992 (N = 6305) in the Minneapolis-St Paul, Minn, metropolitan area as part of the Minnesota Heart Survey. Personal interviews about knowledge of cholesterol level and hypercholesterolemia awareness and treatment were conducted. Total serum cholesterol was measured; hypercholesterolemia was defined as having a total cholesterol level of 6.21 mmol/L or more (> or = 240 mg/dL) or current use of cholesterol-lowering medications. Hypercholesterolemia awareness was defined as the belief of a participant with hypercholesterolemia that her or his total cholesterol was high. RESULTS: Knowledge increased from 15% in 1980-1982 to 17% in 1985-1987 to 55% in 1990-1992 (P < .001) in women; similar trends were observed for men (19%, 22%, and 47%, respectively; P < .001). Hypercholesterolemia awareness doubled during the decade (women: 17%, 1980-1982; 24%, 1985-1987; 60%, 1990-1992; P < .001; men: 25%, 30%, and 55%, respectively; P < .001). Among participants who reported physician-diagnosed hypercholesterolemia, the prevalence of current pharmacological treatment increased from 9% in 1980-1982 to 14% in 1990-1992 in women, and from 7% to 13%, respectively, in men. CONCLUSIONS: Cholesterol knowledge and hypercholesterolemia awareness and treatment increased substantially during the 1980s, concurrent with educational initiatives of the National Cholesterol Education Program and other efforts.
Adult↗
Comparison of medical care and one- and 12-month mortality of hospitalized patients with acute myocardial infarction in Minneapolis-St. Paul, Minnesota, United States of America and Göteborg, Sweden.
We compared medical care and mortality through 1-year of hospitalized acute myocardial infarction (AMI) patients in 2 large metropolitan areas in the United States and Sweden. All hospitalized AMI discharges (International Classification of Diseases, 9th revision [ICD9] codes 410) occurring among 30 to 74-year-old residents of the Minneapolis-St. Paul metropolitan area in 1990 and Göteborg, Sweden, in 1990 to 1991 were identified and their medical records examined. There were dramatic differences in medical care during the index hospitalization of AMI patients between Minneapolis-St. Paul and Göteborg. Use of thrombolytic therapy, coronary angioplasty, bypass surgery, calcium antagonists and lidocaine was more common in Minneapolis-St. Paul; beta blockers were more frequently used in Göteborg, and aspirin use was similar. Despite these large differences, neither 28-day nor 1-year mortality of hospitalized AMI patients differed significantly. The marked differences found in the early treatment of AMI between Minneapolis-St. Paul and Göteborg, combined with the negligible differences observed in short- and long-term mortality, raise questions about the most effective and efficient allocation of medical resources.
Adult↗
Antioxidants and ischaemic heart disease.
Explore the source record for details and available documents.
Antioxidants↗
Neighborhood environments and coronary heart disease: a multilevel analysis.
The authors investigated whether neighborhood socioeconomic characteristics are associated with coronary heart disease prevalence and risk factors, whether these associations persist after adjustment for individual-level social class indicators, and whether the effects of individual-level indicators vary across neighborhoods. The study sample consisted of 12,601 persons in four US communities (Washington County, Maryland; Forsyth County, North Carolina; Minneapolis, Minnesota; and Jackson, Mississippi) participating in the baseline examination of the Atherosclerosis Risk in Communities Study (1987-1989). Neighborhood characteristics were obtained from 1990 US Census block-group measures. Multilevel models were used to estimate associations with neighborhood variables after adjustment for individual-level indicators of social class. Living in deprived neighborhoods was associated with increased prevalence of coronary heart disease and increased levels of risk factors, with associations generally persisting after adjustment for individual-level variables. Inconsistent associations were documented for serum cholesterol and disease prevalence in African-American men. For Jackson African-American men living in poor neighborhoods, coronary heart disease prevalence decreased as neighborhood characteristics worsened. Additionally, in African-American men from Jackson, low social class was associated with increased serum cholesterol in "richer" neighborhoods but decreased serum cholesterol in "poorer" neighborhoods. Neighborhood environments may be one of the pathways through which social structure shapes coronary heart disease risk.
Black or African American↗
Translating clinical trials into practice.
Explore the source record for details and available documents.
Clinical Trials as Topic↗
Immune globulins are effective in severe pediatric Guillain-Barré syndrome.
The effect of high-dose intravenous immune globulins was evaluated in an open prospective multicenter study of 26 children with severe Guillain-Barré syndrome. They presented with mild to moderate flaccid weakness of extremities, with cranial nerve involvement (20) and sensory impairment (22). All children rapidly deteriorated in 2-16 days (mean 6) to become bedridden, and 2 children also developed respiratory failure requiring artificial ventilation (Disability Grading Scale 4-5). Immune globulins were then administered at a total dose of 2 gm/kg, on 2 consecutive days, without adverse effects requiring discontinuation of therapy. Marked and rapid improvement was noted in 25 children, who improved by 1 to 2 Disability Grade Scales < or = 2 weeks after the infusion. Twenty were able to walk independently by 1 week, and 1 could be weaned off a ventilator. Eighteen children recovered by 2 weeks. The rest recuperated in a period of four months, including a child who was artificially ventilated for 4 weeks. The uniform rapid improvement and recovery associated with immune globulins contrasts with the slow recovery course in severe natural cases. We conclude that immune globulins are effective and safe in severe childhood-onset Guillain-Barré syndrome and therefore may serve as the initial treatment of choice.
Adolescent↗
Assessment of endocrine functions in children following severe head trauma.
The goal of the present study was to assess endocrine functions in children following severe head trauma. Subjects included 21 children between the ages of 3 years and 18 years 6 months, referred to the Pediatric Rehabilitation Unit at Sheba Medical Center, Israel, between 1984 and 1995. Each was examined 4 months to 11 years following the first admission, undergoing a complete physical examination, including neurologic assessment, biochemical and baseline endocrine profiles, and bone age determination. A GnRH stimulation test was performed in prepubescent children who had advanced bone age. Sixteen children had experienced the head trauma before, or at onset of puberty, according to their chronologic ages. Two children had completed puberty before the head trauma. A 12-year-old male who sustained head trauma at 10 years 6 months of age was found to have Tanner grade 3 pubertal stage and advanced bone age. In addition, 3 prepubescent children also had advanced bone age with no other signs of precocious puberty and a normal GnRH test. For all children studied, the biochemical and hormonal laboratory measurements were in the normal range. Endocrine abnormalities were not found in children examined 4 months or more following severe head trauma. We conclude that clinical monitoring of endocrine status after severe head trauma is sufficient; specific hormonal measurements are not required unless warranted by abnormal physical signs.
Adolescent↗
A Popperian perspective of the term 'evidence-based medicine'.
If the term 'evidence-based medicine' conveys more than is conveyed by the word medicine, then there must be a way to distinguish between evidence-based medicine and non-evidence-based medicine. In particular, there must be a logically acceptable way to classify medical decisions as justified or unjustified by scientific evidence. In this essay I examine the nature of medical theories, the nature of the evidence that is produced by empirical tests of medical theories, and the relation of medical decisions to both. I conclude that attempts to classify medical decisions as justified or unjustified by scientific evidence have no foundation in logic and that the term 'evidence-based medicine' is logically indistinguishable from the term 'medicine'. The use of the term 'evidence-based medicine' calls for a new type of authoritarianism in medical practice.
Authoritarianism↗
Autoimmune progesterone dermatitis: effective prophylactic treatment with danazol.
BACKGROUND: Autoimmune progesterone dermatitis is a rare condition appearing during the perimenstrual period or following progesterone treatment. Various treatment modalities have been suggested, but most have proved to be ineffective. METHODS: We used the anabolic androgen danazol as a preventive treatment for recurrent episodes of autoimmune progesterone dermatitis in two young women. The treatment regimen consisted of 200 mg danazol twice daily, starting 1-2 days before the expected date of each menses and continuing for 3 days thereafter. RESULTS: This treatment regimen proved to be highly effective in preventing the eruptions in these two patients. CONCLUSIONS: Patients with autoimmune progesterone dermatitis may benefit from prophylactic treatment with danazol.
Adult↗
The prevalence and severity of white matter lesions, their relationship with age, ethnicity, gender, and cardiovascular disease risk factors: the ARIC Study.
White matter lesions (WMLs) detected by cerebral magnetic resonance imaging (MRI) are putatively a consequence of cerebral hypoperfusion or ischemia. We investigated the prevalence, severity and correlates of WMLs in a population-based sample of 1,920 African-American and European-American men and women aged 55-72 years, during the second follow-up examination of the Atherosclerosis Risk in Communities Study. The spin density images from 1.5-tesla MRI scans were used to define WMLs using a 0-9 scale with 0 for normal and 9 for most severe WMLs. Age was positively associated with the prevalence (percent) and severity of WMLs. African-Americans had lower overall prevalence of WMLs, but a higher prevalence of relatively more severe WMLs, than European-Americans. After adjusting for age, sex, and ethnicity, WMLs were significantly associated with smoking, lower education, hypertension, systolic blood pressure, and pulse pressure, and weakly associated with diastolic blood pressure. The associations of smoking, alcohol intake, systolic and diastolic blood pressure, pulse, pressure, and hypertension were stronger in African-Americans than in European-Americans (p < 0.15 for interactions by ethnicity). This population-based MRI study documents significant relationships between several cardiovascular disease risk factors and WMLs. The findings suggest that such factors play a role in the pathogenesis of WMLs, an elements linked to hypoperfusion and/or fluid accumulation, which presumably lead to WMLs. African-Americans exhibited both a higher proportion of normal white matter and a higher proportion of relatively more severe WMLs than European-Americans.
Age Factors↗
Familial history of stroke and stroke risk. The Family Heart Study.
BACKGROUND AND PURPOSE: Although familial history of stroke is generally perceived to be an important marker of stroke risk, very few epidemiological studies have been published to address this hypothesis. We sought to examine whether familial history of stroke is associated with the prevalence of stroke in the Family Heart Study, a National Heart, Lung, and Blood Institute-supported multicenter study of the familial, genetic, and nongenetic determinants of cardiovascular disease in populations. METHODS: The personal and familial histories of stroke were assessed in 3168 individuals (probands) who were at least 45 years old and 29,325 of their first-degree relatives with the use of a standardized questionnaire. RESULTS: The age-, ethnicity-, and sex-adjusted stroke prevalences were 4.8%, 4.9%, and 3.9% in probands with a positive familial, paternal, and maternal history of stroke, respectively, in comparison with 2.0% in probands without any positive familial history (P < .01). The age-, ethnicity-, and sex-adjusted odds ratios (95% confidence interval) of stroke were 2.00 (1.13, 3.54) for a positive paternal and 1.41 (0.80, 2.50) for a positive maternal history of stroke. Additional statistical adjustment for the proband's history of elevated cholesterol level, cigarette smoking status, history of coronary heart disease, hypertension, and diabetes did not alter the associations. A similar pattern was seen for African Americans and European Americans. CONCLUSIONS: The increased risk of stroke among persons with a positive familial history of stroke compared with those without a familial history of stroke is consistent with the expression of genetic susceptibility, a shared environment, or both in the etiology of stroke.
Black or African American↗