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PubMedDate not supplied

[Iron-deficiency anemia in enteral nutrition: correlation with tube position].

Enteral alimentation is a commonly employed procedure for pre-operative rehabilitation and nutritional maintenance of depleted patients suffering from esophageal diseases. In a prospective study of 61 cases exhibiting benign (n = 38) and malignant (n = 23) conditions, a commercial polymeric diet was supplied in the proportion of 40 Kcal/kg/day during at least two weeks. The liquid preparation was infused by bolus technique at home, by the patients themselves, via nasogastric (n = 25) or nasoduodenal silastic tube (n = 36). Total food intake, that before treatment had been under 60% of estimated requirements, reached the expected range throughout the therapeutic period, and also iron input was adequate (0.3 mg/kg/day). Standart anthropometric and biochemical assessment of these cases, with included serum iron and hemoglobin concentration, indicated stabilization of general nutritional parameters, but with persistence of moderate anemia(hemoglobin 12.6 +/- 2.0 g/dl; iron 59.2 +/- 35.7 mg/dl). Stratification of the population according to enteral tube position demonstrated similar diagnoses and clinical conditions for both groups. Mean initial iron and hemoglobin concentration was also the same, but final serum iron was increased after gastric administration (p < 0.05) and diminished with duodenal diet (p < 0.05). It is concluded that: home enteral nutrition in malnourished patients with esophageal diseases is consistent with an acceptable nutritional status, but without significant recovery from anemia, serum iron in this population only increases after intra-gastric alimentation; it is probable that this last finding is related to impaired ionization and absorption of dietary iron, when food is introduced in a postpyloric site.

Anemia, Iron-Deficiency↗
PubMedDate not supplied

Role of electrophysiologic studies, signal-averaged electrocardiography, heart rate variability, T-wave alternans, and loop recorders for risk stratification of ventricular arrhythmias.

Ventricular tachycardia and fibrillation are major causes of morbidity and mortality after myocardial infarction. Frequently, sudden cardiac death is the first manifestation of such malignant rhythms. Optimal risk stratification strategies in this population are of utmost importance. In this review the authors discuss the background and clinical use of invasive tests, such as electrophysiologic study and implantable loop recorders, and noninvasive tests, such as signal-averaged electrocardiography, heart rate variability, and T-wave alternans. The utility, indications, and limitations of each test in clinical practice are discussed, especially for the purpose of postmyocardial infarction risk stratification in the elderly population.

Action Potentials↗
PubMed1992

The Second National Acute Spinal Cord Injury Study.

In 1990, the Second National Acute Spinal Cord Injury Study reported that high-dosage methylprednisolone improves neurologic recovery in spinal-injured humans. The study showed that patients who received the drug within 8 hr after injury improved, whereas those who received the drug later did not. The drug significantly increased recovery even in severely injured patients who were admitted with no motor or sensory function below the lesion, contradicting a long-held dogma that such patients would not recover. Some researchers, however, have questioned the stratification of the patient population, the use of summed neurologic change scores, and the absence of functional assessments. The stratification by injury severity and treatment time was planned a priori and based on objective criteria. Detailed analyses revealed no differences between groups attributable to stratification or randomization. While multivariate analyses of the summed neurologic scores were used, the conclusions were corroborated by other analytical approaches that did not rely on summed scores. For example, treatment with methylprednisolone more than doubled the probability that patients would convert from quadriplegia or paraplegia to quadriparesis or paraparesis, analgesia to hypalgesia, and anesthesia to hypesthesia. The treatment also significantly improved neurologic scores in lumbosacral segments, indicating that beneficial effects were not limited to segments close to the lesion site. The treatment did not significantly affect mortality or morbidity. The study strongly suggests that methylprednisolone has significant beneficial effects in human spinal cord injury, that these effects occur only when the drug is given within 8 hr, and that it helps even in patients with severe spinal cord injuries. These conclusions have important implications for spinal cord injury care and research.

Drug Administration Schedule↗
PubMed2006

Predictive value of microvolt T-wave alternans for sudden cardiac death in patients with preserved cardiac function after acute myocardial infarction: results of a collaborative cohort study.

OBJECTIVES: We conducted a collaborative cohort study to evaluate the predictive power of microvolt T-wave alternans (TWA) in patients with preserved left ventricular ejection fraction (LVEF) after myocardial infarction (MI). BACKGROUND: There is little information available about the prognostic value of risk stratification markers in this population. Although these patients have a relatively good prognosis, identifying high-risk patients is important in clinical practice. METHODS: This study enrolled 1,041 post-MI patients with an LVEF > or =40% (average 55 +/- 10%). Microvolt TWA testing was performed 48 +/- 66 days after acute MI, and 10 other risk variables were also evaluated. The end points were prospectively defined as sudden cardiac death or life-threatening arrhythmic events. RESULTS: During a follow-up of 32 +/- 14 months, 38 patients (3.7%) died of nonarrhythmic causes and were not considered for analysis. Of the 1,003 evaluable patients, 18 (1.8%) reached an end point. Microvolt TWA was positive in 169 patients (17%), negative in 747 (74%), and indeterminate in 87 (9%). A positive microvolt TWA test, nonsustained ventricular tachycardia, and ventricular late potentials were predictors of events, and percutaneous coronary intervention decreased the risk rate. On multivariate analysis, a positive microvolt TWA test was the most significant predictor, with a hazard ratio of 19.7 (p < 0.0001). This marker had the highest sensitivity and negative predictive value for events. CONCLUSIONS: In patients with preserved cardiac function, the incidence of indeterminate results of microvolt TWA is low, and a positive test result is associated with arrhythmic events. Microvolt TWA could be used for risk stratification in this low-risk population.

Aged↗
PubMed1991

Microgeographic distribution of allele frequencies in populations of Calomys laucha (Rodentia, Cricetidae).

The microgeographic differentiation of allelic frequencies was analysed in two population samples of Calomys laucha, collected in a grid set in cultivated fields at Laguna Larga (Córdoba province, Argentina). One of the samples (n = 79) was obtained in May (Autumn), when the population density is at a maximum, and the other (n = 85) in November (spring), at the onset of reproductive activity. FST values for the November sample show significant differences between the six groups over which the sample was divided. FIT values show an excess of homozygotes for some loci in both samples. FIS reveals an excess of homozygotes within each of the groups. These results indicate the existence of subdivision in the population. Because C. laucha is a reservoir host of the Junin virus, an agent of endemic disease, this social organization may have epidemiological implications. Stratification of C. laucha populations into small breeding units could be one of the factors responsible for the high genic variability detected in this species.

Alleles↗
PubMed2006

SNP-based analysis of genetic substructure in the German population.

OBJECTIVE: To evaluate the relevance and necessity to account for the effects of population substructure on association studies under a case-control design in central Europe, we analysed three samples drawn from different geographic areas of Germany. Two of the three samples, POPGEN (n = 720) and SHIP (n = 709), are from north and north-east Germany, respectively, and one sample, KORA (n = 730), is from southern Germany. METHODS: Population genetic differentiation was measured by classical F-statistics for different marker sets, either consisting of genome-wide selected coding SNPs located in functional genes, or consisting of selectively neutral SNPs from 'genomic deserts'. Quantitative estimates of the degree of stratification were performed comparing the genomic control approach [Devlin B, Roeder K: Biometrics 1999;55:997-1004], structured association [Pritchard JK, Stephens M, Donnelly P: Genetics 2000;155:945-959] and sophisticated methods like random forests [Breiman L: Machine Learning 2001;45:5-32]. RESULTS: F-statistics showed that there exists a low genetic differentiation between the samples along a north-south gradient within Germany (F(ST)(KORA/POPGEN): 1.7 . 10(-4); F(ST)(KORA/SHIP): 5.4 . 10(-4); F(ST)(POPGEN/SHIP): -1.3 . 10(-5)). CONCLUSION: Although the F(ST )-values are very small, indicating a minor degree of population structure, and are too low to be detectable from methods without using prior information of subpopulation membership, such as STRUCTURE [Pritchard JK, Stephens M, Donnelly P: Genetics 2000;155:945-959], they may be a possible source for confounding due to population stratification.

Case-Control Studies↗
PubMed2003

Comparison of various score systems for risk stratification in heart surgery.

UNLABELLED: Its is important to predict patients having the highest risk of surgery. Risk stratification systems need to be tested in different surgical populations and whether they are or not appropriate to our population remains unknown. OBJECTIVE: To test various risk stratification systems for our region population having cardiac surgery in our institution during 2002. MATERIALS AND METHODS: Between January 1, 2002 and November 1, 2002, all adult patients undergoing heart surgery with cardiopulmonary bypass in our institution were included in the study and scored using the EuroSCORE, Parsonnet, Ontario, and QMMI. Study was completed by 444 patients. We analyzed score systems predicting characteristics by assessing receiver operating characteristics (ROC). RESULTS: Observed mortality was 25 (5.63%). Mean score for alive and dead patients for EuroSCORE was -7.8+/-3.1 and 10.8+/-3.2, p<0.005; Parsonnet - 14.2+/-11 and 32.5+/-13.8, p<0.0005; Ontario - 3.6+/-2.7 and 6.4+/-3.5, p<0.005; QMMI score - 10.4+/-6.9 and 20.3+/-8.7, p<0.0001. ROC curve analysis for mortality showed best predicting characteristics for the Parsonnet and QMMI, best accuracy for QMMI score - 84.4 %. CONCLUSIONS: Most (71.2%) of our investigated patients having heart surgery are at high-risk group for death. All investigated score systems have significance in mortality prediction. Among the investigated score systems, the QMMI score and Ontario score systems yielded the highest predictive value in our patient population. Highest accuracy of prediction patient population showed QMMI score. Our study highlighted over prediction of mortality for Parsonnet score and EuroSCORE systems for our population.

Adult↗
PubMed2005

[Use of a coronary risk score (the TIMI Risk Score) in a non-selected patient population assessed for chest pain at an emergency department].

INTRODUCTION AND OBJECTIVES: Stratification algorithms for acute coronary syndrome enable the identification of high-risk patients who will benefit from more aggressive treatment. The TIMI Risk Score (TRS) has been shown to be useful in intermediate- and high-risk patients. However, little is known about its value in non-selected patients. Our aim was to assess the efficacy of the TRS for risk stratification in a non-selected population with chest pain. PATIENTS AND METHOD: We evaluated 1254 consecutive patients (age, 54 [19] years; 57% male) attending an emergency department for chest pain. Overall, 343 (27%) were admitted and 911 (73%) were discharged. All cardiac events during 6-month follow-up were recorded. RESULTS: Of the 911 discharged patients, 45 (5.3%) were admitted during follow-up: 9 (1.1%) underwent revascularization, 5 (0.6%) had a myocardial infarction (MI), and 2 (0.2%) died from cardiovascular disease. Patients with a high TRS had a significantly higher risk of reaching the composite endpoint of death, MI, or revascularization (relative risk per unit of TRS increase, 3.63; 95% CI, 2.20-6.00; P < .001). Of the patients who were initially admitted, 22 (6.4%) underwent revascularization, 4 (1.2%) had an MI, and 14 died (4.1%) from cardiovascular disease during follow-up. The relative risk of the composite endpoint per unit of TRS increase was 1.72 (95% CI, 1.32-2.24; P < .001). CONCLUSIONS: The TIMI risk score is useful for stratifying cardiovascular event risk in non-selected patients with chest pain. The score can identify high-risk patients who will benefit from hospital admission and early aggressive treatment.

Adult↗
PubMed1999

Stroke risk in an elderly population with atrial fibrillation.

Patients with nonvalvular atrial fibrillation (AF) have an increased risk of stroke, but the absolute rate of stroke varies widely depending on coexistent vascular disease. We assessed the stroke rate and predictive value of two published schemes for stroke risk stratification in a population-derived cohort of 259 elderly people with nonvalvular AF followed for a median of 5.3 years. The rate of ischemic stroke was 2.8% per year (95% confidence interval [CI] 1.9, 3.9). Thirty-one percent were predicted to be at low risk, and their stroke rate was 1.7% per year (95% CI 0.6, 3.8). Many people with AF in this population-derived cohort had relatively low rates of stroke. Further studies to reliably stratify stroke risk in patients with AF are needed.

Aged↗
PubMed2005

[Risk stratification in pre-hospital management of myocardial infarction with ST elevation: value of a risk score profile].

The aims of this study were to evaluate new tools of risk stratification in an unselected population of myocardial infarction (MI), usable in a pre-hospital situation, and to compare the risk profile of these patients with those of other clinical trials or myocardial infarction registries. The risk scores of death at 30 days (TIMI score and TIMI risk index) based on data available in the context of coronary emergencies, were applied to the population base of the MI observatory of myocardial infarction in the Côte d'Or (RICO). The risk profile was expressed by the smoothed graph of frequency distribution of each score. The TIMI score applied to the RICO population had a high discriminating power (c = 0.80) for mortality whereas TIMI risk index was less powerful (c = 0.57). The risk profile of the RICO population was comparable to that of InTIME II, ASSENT 2 and the NRMI with reperfusion registry. The NRMI without reperfusion and the MAGIC studies had different profiles characterised by a shift in the graph towards high risk patients. The authors conclude that risk stratification scores, like the TIMI score, are valuable tools for early triage in the management of MI patients. The risk profiles allow comparative analysis of risk levels of populations notably with respect to other registries and also with respect to randomised clinical trials.

Aged↗
PubMedDate not supplied

[Management of essential arterial hypertension and cardiovascular risk levels. Observation in general medicine: national PHENOMEN study. Evaluation and stratification of cardiovascular risk based on the 2000 ANAES recommendations in a population of hypertensive patients].

OBJECTIVE: To define the prevalence of cardiovascular risk (CVR) levels in a population of hypertensive patients (whether treated or not) monitored by General Practitioners, using the stratification system proposed by the ANAES in 2000. METHODS: Between January and July 2001, a nation-wide survey was carried out based on a representative sample of 8,177 General Practitioners spread evenly throughout all of the 22 administrative regions in France. The evaluation of CVR levels took into account blood pressure readings as well as CVR factors and indicators. RESULTS: This survey covered 16,358 patients (53.2% men, 46% women; mean age = 62.5 +/- 11.9 years; BMI = 27.3 +/- 4.5 kg/m2) with a mean history of hypertension of 7 +/- 7 years. The most common CVR factors were dyslipidemia (59.5%), smoking (19%) and diabetes (16%). Concomitant target organ damage was recorded in 17% and heart disease in 21.8%. One patient in four had more than three CVR factors; respectively 56.5%, 30.9% and 12.5% of the patients had mild, moderate or severe hypertension. More than 50% of the patients were classified as being at "high" or "very high" CV risk. The distribution of risk levels was similar throughout the country with a North-South gradient of the high/very high levels. Only 17% of the patients being treated had completely normal blood pressure (< 140/190 mmHg), although 19% more count as normal if the limit values are included. CONCLUSION: The main objective of this large-scale, nation-wide epidemiological survey was to evaluate how well CVR is being managed in a representative sample of patients with high blood pressure. In general, none of the risk factors is adequately controlled, especially in populations considered as being at high CVR. Moreover, the notion of CVR has only been partially assimilated by General Practitioners.

Aged↗
PubMed2003

Validity of a simple ST-elevation acute myocardial infarction risk index: are randomized trial prognostic estimates generalizable to elderly patients?

BACKGROUND: Risk-stratification scores derived from randomized clinical trial (RCT) data should be evaluated in community-based populations. A simple risk-stratification index for patients with ST-segment elevation myocardial infarction derived from an RCT population was recently proposed, but it has not been validated in a community-based cohort. METHODS AND RESULTS: We evaluated the simple risk index using data from 49 711 patients > or =65 years of age hospitalized with ST-elevation myocardial infarction. We evaluated the distribution of patients in the 5 simple risk index groups, compared observed and published 30-day mortality rates, and assessed the score's discrimination and calibration. The simple risk index provided poor discrimination (c=0.62) and calibration (goodness of fit P<0.001) for survival at 30 days. Risk score distribution was skewed, because two thirds (66.1%) of all patients were classified in the highest-risk group, whereas fewer than 11.0% were classified in the 3 lowest-risk groups. Thirty-day mortality estimates were lower than those observed in the cohort (risk group 2 to 5: 1.9% to 17.4% versus 5.3% to 27.9%). Risk index discrimination, calibration, score distribution, and mortality estimates were worse among patients who did not receive acute reperfusion therapy than among those who did. CONCLUSIONS: The limited performance of the simple risk index highlights the limitations of applying prognostic models derived in RCT populations to the general population of patients 65 years and older. Prognostic scores must be validated in community-based cohorts before integration into clinical practice.

Aged↗
PubMed1992

Relationship of the type of tobacco and inhalation pattern to pulmonary and total mortality.

Data from The Copenhagen City Heart Study, a prospective population study, were analysed to investigate the influence of the type of tobacco and inhalation on pulmonary and total mortality. The study sample comprised 6,511 men and 7,703 women, selected randomly after age-stratification from the general population. There were 2,986 plain cigarette smokers, 3,222 filter cigarette smokers, 1,578 smokers of cheroots/cigars, 433 male pipe smokers and 773 subjects smoking more than one type of tobacco. From 1976 until the end of 1989, 2,765 subjects died. Lung cancer was considered as main death cause in 268. Chronic obstructive pulmonary disease (COPD) was considered as the main cause in 94 cases and main or contributory cause of death in 195 cases (COPD related mortality). Current smokers had a higher risk of total mortality compared to lifetime nonsmokers: the relative risks (RR) ranged between 1.2 for male pipe smokers and 2.4 for female plain cigarette smokers. With regard to lung cancer mortality, the RR ranged between 4.1 for male pipe smokers and 7.9 for female plain cigarette smokers. Even higher RR values were estimated for COPD related mortality. In both sexes, the RR for the investigated end-points were lower in cheroot/cigar smokers and in pipe smokers than in cigarette smokers, but these differences were markedly diminished after an adjustment for the inhalation habit. The present study substantiates the view that tobacco smoking increases pulmonary and total mortality. The small differences between the various types of tobacco are probably caused by different inhalation patterns.

Adult↗
PubMed2006

Hypertension: a new look at an old problem.

PURPOSE OF REVIEW: This review reports the specific impact that hypertension, identified by its component subtype classification, has on perioperative outcomes. Most importantly, we review the risk of systolic hypertension and pulse pressure hypertension independent of elevated diastolic blood pressure on patients undergoing cardiac surgery. RECENT FINDINGS: Systemic hypertension is identified as a major risk factor for cardiovascular morbidity in most larger population-based studies. Nearly a third of the population in the United States has or will have some form of hypertension disease, with many under-diagnosed or under-treated. Classification of hypertensive subtypes has been well recognized as an important component for risk stratification in the ambulatory population in recent years, but remains poorly recognized in the surgical setting. We present recent data unveiling the importance of pulse pressure above that of systolic and diastolic pressures. SUMMARY: The evidence is compelling that wide pulse pressure hypertension is a strong and an independent predictor of adverse perioperative renal, cerebral and mortality outcomes. We discuss the physiology for this important novel observation in an acute surgical patient population and provide an explanation.

Anesthesia↗
PubMed1988

Morphological diversity of displaced retinal ganglion cells in the rat: a lucifer yellow study.

Displaced retinal ganglion cells (DRGCs) were retrogradely labelled by injections of the fluorescent dye Fast Blue into the superior colliculi of pigmented rats. Following fixation these cells were intracellularly injected with Lucifer Yellow to determine their dendritic morphology and distribution. Graphic reconstruction of Lucifer Yellow-filled prelabelled neurones revealed a heterogeneous population of DRGCs. Their stratification within the inner plexiform layer was diverse and cells were classified according to their dendritic morphology. The present sample consists largely of unistratifying neurones, the dendrites of which arborized within a narrow sublamina of the inner plexiform layer. They were characterized by a centrally located soma and densely branched dendritic network with little overlap within the branching pattern. In contrast, bistratifying DRGCs possessed a loose and sparsely branched dendritic structure, while diffusely stratifying neurones contained a high degree of dendritic crossing, culminating in a complex network, in which the soma position was biased toward the periphery. One type of DRGC bore a striking resemblance to type 1 neurones (Perry, 1979; Proc. R. Soc. Lond. [Biol.] 204:363-375) in the ganglion cell layer. They were characterized by a large soma (15.5 micron +/- 2.2 micron s.d.) and a dendritic field diameter averaging 288 micron (s.d. +/- 62 micron) and were on average larger than the rest of the displaced population but smaller than type 1 cells in the ganglion cell layer. Since the stratification patterns of the displaced and nondisplaced type 1 neurones were indistinguishable, it is reasonable to assume that the Lucifer Yellow-filled cells in the present study represent the displaced counterpart of regular type 1 ganglion cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2003

Social stratification, development and health in Pakistan: an empirical exploration of relationships in population-based national health examination survey data.

There is a growing literature on an overall direct relationship between health and social position in developed countries. The relationship, however, is less well documented in developing countries where social hierarchies are changing more rapidly, demographic and health transitions are less advanced, and this topic has received less attention from researchers than in some developed countries. This paper presents an empirical investigation of the relationship between social stratification and social development and population health using data on over 6000 adults from the National Health Survey of Pakistan, a nationally representative health examination survey of people in that country. We analyze four indicators of poor nutrition in adults from this data set. The findings reveal complex relationships among social development, social stratification and the consequences for the health of the people of Pakistan. Underweight is related to economic status, anemia to education and social development, and both severe dental caries and a monotonous diet are related to both development and economic status which interact with each other. These results suggest that continued conceptual refinement and the development of standardized measures of stratification and development would contribute to building cross-nationally comparable data sets addressing issues of the relationship among health and economic development and health transitions.

Adolescent↗
PubMed2006

Emergency department visits for asthma: the role of frequent symptoms and delay in care.

BACKGROUND: Use of the emergency department (ED) for asthma care is a costly form of health care that is largely preventable. However, little is known about how to reduce the number of people using the ED for asthma care. OBJECTIVE: To identify modifiable factors related to ED visits for asthma among a diverse nonelderly adult population. METHODS: This study used cross-sectional data from the 2001 California Health Interview Survey. A total of 4,359 adult respondents ages 18 to 64 years who reported being diagnosed as having asthma and experiencing symptoms in the past year were included. Any ED visits due to asthma in the previous 12 months among all nonelderly respondents with asthma, with stratification by those with daily or weekly symptoms and with less frequent symptoms, were examined. RESULTS: Adults with daily or weekly asthma symptoms, with fair or poor health status, and who delayed care for asthma because of cost or insurance issues were more likely to visit the ED for asthma. Stratification of the study population into those with daily or weekly symptoms and those with less frequent symptoms revealed that delay in care due to cost or insurance issues and fair or poor health status remained significant for both groups. Latinos and women were more likely to visit the ED in the severe asthma group, whereas Asian, African American, and uninsured adults were more likely to visit the ED in the group with less severe asthma. CONCLUSIONS: Results suggest that to prevent ED visits for asthma, it is important to control asthma symptoms. However, it is equally if not more important to reduce delays in receiving asthma care.

Adolescent↗
PubMed2003

Occupation and breast cancer in women 20-44 years of age (United States).

OBJECTIVE: To examine the relation between breast cancer risk and job history among women 20-44 years of age who participated in a multi-center, population-based, case-control study. METHODS: Participants consisted of women newly diagnosed with breast cancer (1642) and controls identified by random-digit dialing (1494). Details about the three longest jobs were collected and coded by an industrial hygienist. Odds ratios and 95% confidence intervals were calculated and adjusted for age, study site, and other breast cancer risk factors. RESULTS: Several occupational and industrial categories were found to influence breast cancer risk. Stratification of the study population by parity revealed differences in breast cancer risk between the two groups for several occupational categories, including teachers, librarians or counselors (increased risk only among parous women) and natural scientists and mathematicians (decreased risk only among nulliparous women). CONCLUSIONS: This is among the first population-based case-control studies to examine occupational history and breast cancer risk in young women, with the ability to consider a wide array of potential confounders, including reproductive characteristics. This study provides further evidence of an increased breast cancer risk for several occupations and industries. Other findings were not as strongly supported by previous investigations.

Adult↗