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Biomedical subjects

R Brand

Publications and source records attributed to R Brand.

At least 127 records · Page 7Linked to original sources
PubMed1993

Ischemic and hemorrhagic stroke in patients on oral anticoagulants after reconstruction for chronic lower limb ischemia.

BACKGROUND AND PURPOSE: Information on the long-term fate of patients with chronic lower limb ischemia is limited. We investigated the long-term risk of the first ischemic and hemorrhagic cerebral stroke in patients on long-term anticoagulant therapy after reconstruction for chronic limb ischemia. METHODS: In a retrospective study, 376 consecutive patients were seen at regular intervals according to a standard protocol. Only 3 (0.7%) were lost during follow-up (mean duration, 5.9 years). Anticoagulation was with coumarin derivatives followed by prothrombin times periodically. Primary end points were ischemic and hemorrhagic cerebral stroke events, which were confirmed by CT scan, autopsy, or operation in 85% of the cases. Major vascular events were analyzed as a composite secondary end point. The influence of several clinical variables on these outcome events was evaluated in univariate and multivariate analyses. RESULTS: Thirty-nine patients (10%) had 41 stroke events (23 ischemic, 18 hemorrhagic); 22 of these patients (56%) died from stroke. The cumulative ischemic stroke risk was 5% at 5 years and 12% at 15 years. Prior myocardial infarction was the only independent predictor (relative risk [RR], 3.1; P < .05). The cumulative hemorrhagic stroke risk was 3% at 5 years and 17% at 15 years. Systolic hypertension (RR, 4.8; P < .01) and insulin-dependent diabetes mellitus (RR, 5.4; P < .01) were significant and independent predictors. The risk for a major vascular event was 29% at 5 years and increased to 56% at 15 years. Independent predictors were advanced age (RR, 1.4; P < .005), insulin-dependent diabetes (RR, 2.2; P < .005), and prior myocardial infarction (RR, 1.8; P < .01). CONCLUSIONS: Patients with chronic lower limb ischemia, notably those with prior myocardial infarction, are at high risk for ischemic stroke. Those with systolic hypertension or insulin-dependent diabetes mellitus are at high risk for hemorrhagic stroke.

Adult↗
PubMed1993

Outcome of periventricular-intraventricular haemorrhage at five years of age.

The authors studied the relationship between periventricular-intraventricular haemorrhage in infants of < 32 weeks gestation who had undergone routine cranial ultrasound scanning in the neonatal period, and neurodevelopmental outcome at the age of five years. Of 484 infants enrolled into the study, all 304 survivors were available for follow-up at the age of five years. 85 children had a disability; in 50 of these, the disability caused a handicap. Three children with dilated lateral ventricles and no periventricular-intraventricular haemorrhage were excluded from further analyses. 26 per cent of the infants with severe (grades III/IV) haemorrhage and 67 per cent of the infants with mild (grades I/II) haemorrhage survived the neonatal period. Children with mild haemorrhage had a significantly increased risk of disability (including handicap) at the age of five years.

Central Nervous System Diseases↗
PubMed1993

Late nonfatal and fatal cardiac events after infrainguinal bypass for femoropopliteal occlusive disease during a thirty-one-year period.

PURPOSE AND METHODS: In patients with peripheral vascular disease the complications of associated coronary artery disease have always been a leading cause of morbidity and mortality. Therefore we evaluated the risk for late cardiac morbidity and mortality in 376 consecutive patients after infrainguinal bypass. Follow-up was complete for 373 patients (99.3%) with a mean follow-up period of 5.9 years. After operation all but four patients were treated with lifelong warfarin (Coumadin therapy.) RESULTS: During follow-up 129 patients (34.3%) had 183 late cardiac events. Of these patients, 79 (61.2%) died of late cardiac events and 13 (10.0%) required either coronary angioplasty or bypass. The risk of late cardiac events was 34% at 5 years and increased to 56% at 15 years. Multivariate analysis demonstrated that age, cardiac disease, and impaired renal function at the time of operation were associated with an increased risk of cardiac events during follow-up. Independent predictors of cardiac death were age, cardiac disease, hypertension, diabetes, and impaired renal function. Morbidity and mortality was particularly high in patients with critical ischemia. The subset of patients with claudication had a life expectancy that appeared to be similar to that of a matched sample of the normal population. CONCLUSIONS: Our findings clearly demonstrate that some patients undergoing infrainguinal bypass are at high risk for late cardiac events of which many are fatal, whereas others may have an almost normal life expectancy. Most important, the occurrence of cardiac events may be predicted by simple and readily obtainable clinical variables at the time of the initial infrainguinal bypass procedure. Because these events were related to late cardiac death, this may be the key for angiographic evaluation and possible prevention of cardiac death.

Arteriosclerosis↗
PubMed1992

[Perinatal registration: a pilot study of matching of data from the National Obstetrics Registration and the National Neonatology Registration].

The application of a statistical matching procedure was tested in a pilot study, linking data from the National Obstetrics Registration (hospital-based) with data from the pilot National Neonatology Registration. Linkage appeared feasible, maintaining anonymity of the registered mother-infant pairs. The perinatal database thus formed was suitable for perinatal epidemiological research. Consequently a continuous perinatal database may be formed from the operational home and hospital based National Obstetrics Registration and the National Neonatology Registration which has started on June 1, 1991, allowing ongoing surveillance of perinatal care in the Netherlands.

Confidentiality↗
PubMed1992

Importance of trends in the interpretation of an overall odds ratio in the meta-analysis of clinical trials.

This paper contains a proposition related to the publication of meta-analyses of clinical trials. We consider the situation where the results of a number of trials are summarized by a common or typical odds ratio. We show that stating such an odds ratio as the summary of evidence from a number of trials can be misleading if certain systematic differences between trials exist. In such cases the author should state not just one odds ratio but also its dependence on the relevant characteristics of the trials. In particular, we propose that those reporting a meta-analysis state in advance a (limited) number of variables to be considered for potential interaction with the exposure (risk factor or treatment) of interest. The list might include centre size and the odds in the placebo or control group if such an effect is a priori clinically plausible. The trials should be ordered according to each of these variables and a trend test for the odds ratio should be computed. Apart from a 'genuine' effect, an appreciable interaction could also be indicative of the (multiplicative) odds ratio being an inappropriate measure for the particular meta-analysis. Without any consideration as to the possibility of interaction, the meta-analysis should be considered incomplete. If such an interaction exists, the odds ratio should be stated as a function of the interacting variable, either as a formula or (preferably) in a table stating the odds ratio for a number of different values of the interacting variable, and not as a single summary statistic.

Clinical Trials as Topic↗
PubMed1992

Maternal height and the outcome of labor in rural Tanzania.

The influence of maternal height (standardized for parity and birthweight) on obstetrical outcome is studied in 1095 women giving birth in Lugarawa hospital and 3869 women delivering in Mbozi hospital, both rural hospitals in the South Western Highlands of Tanzania. Short stature was found to increase the need for augmentation of labor in primiparae, the need for operative delivery (cesarean section/symphyseotomy) in all parity groups and the need for vacuum extraction in multiparae. The absence of such an effect of height on perinatal mortality is interpreted as the result of obstetric intervention. It is concluded that maternal height, which is easy to measure, remains a useful tool to predict difficult childbirth and cephalopelvic disproportion.

Birth Weight↗
PubMed1992

Long-term results of prosthetic and non-prosthetic reconstruction for obstructive aorto-iliac disease.

In this retrospective study the results of 518 prosthetic aorto-iliac reconstructions (PRS) and of 229 thrombo-endarterectomies (TEA) were evaluated, with inclusion of follow-up results up to 20 years after surgery. Patients in the PRS group had presented with more severe ischaemic symptoms and more extensive arterio-sclerotic obstructions than the patients in the TEA group. Results in the TEA group were further analysed according to the extension of arterio-sclerotic disease: there were 93 patients with obstructions limited to the aorta or common iliac arteries and 136 patients with more extensive lesions. Patients with limited obstructions were younger, proportionally more often female, had fewer risk factors, and presented with less severe ischaemic symptoms than patients with more extensive obstructions. Operative mortality and early technical and functional results were similar in the PRS and TEA group, but long-term survival and patency rates were significantly better, and the need for late, additional operations was less in the TEA group. Late functional success rates were similar in both groups. The differences in outcome were explained by patient selection. Within the TEA group significantly superior results regarding survival, patency, need for late, additional surgery, and functional success were observed in the subset of patients with obstructions limited to the aorta or common iliac arteries. Considering these results and the risks inherent in a prosthetic reconstruction, such as prosthetic infection and the chance for false aneurysms, we advocate the use of an aorto-iliac TEA in properly selected patients.

Aorta, Abdominal↗
PubMed1992

The influence of handedness on the distribution of muscular weakness of the arm in facioscapulohumeral muscular dystrophy.

The strength of 10 muscle groups in both arms was measured using hand-held myometry to determine the influence of handedness on left-right differences of muscle strength in facioscapulohumeral muscular dystrophy (FSHD). Two groups of subjects were studied: 24 healthy volunteers (19 right-handed), and 53 patients (42 right-handed) with autosomal dominant FSHD. An opposite left-right difference of strength of shoulder and arm muscles was found: right-handed volunteers were stronger on the right side, right-handed patients were stronger on the left side. This opposite left-right difference was statistically significant for the supraspinatus muscle, the wrist extensors and the shoulder internal rotators. The number of left-handed subjects was too small for statistical analysis. The relation between handedness and increased muscle weakness in right-handed FSHD patients suggests that mechanical factors may play a distinct role in the progression of muscle weakness in FSHD.

Adolescent↗
PubMed1992

Standardised method of follow-up assessment of preterm infants at the age of 5 years: use of the WHO classification of impairments, disabilities and handicaps. Report from the collaborative Project on Preterm and Small for gestational age infants (POPS) in The Netherlands, 1983.

A nationwide, prospective study was initiated in The Netherlands in 1983, involving 1338 liveborn infants with a gestational age less than 32 weeks and/or a birthweight less than 1500 g. Pre- and perinatal data, methods and results of follow-up until the corrected age of 2 years have been published previously. In this paper, methods of follow-up at the age of 5 years are described. At that age, 966 children were alive, of which 927 (96%) were assessed during a home visit 2 to 6 weeks after their fifth birthday by three specially trained paediatricians. A questionnaire served to collect data on medical history, respiratory function, behaviour and socio-economic factors. Standardised tests were carried out covering the following 10 areas: congenital malformations, neuromotor function, mental development, hearing, visual function, language and speech development, behaviour, musculoskeletal system, respiratory tract and ENT problems, and growth. The outcome was recorded for separate areas and for the child as a whole using the WHO classification of impairments, disabilities and handicaps.

Abnormalities, Multiple↗
PubMed1992

Evaluation of care for the preterm infant: review of literature on follow-up of preterm and low birthweight infants. Report from the collaborative Project on Preterm and Small for Gestational Age Infants (POPS) in The Netherlands.

Since the introduction of neonatal intensive care in the 1960s, mortality in very preterm and very low birthweight infants has been decreasing steadily. Consequently, interest in the outcome of surviving infants is growing. Restriction of health care resources has stressed the need for information concerning the effect of individual treatment components on mortality and morbidity. Concern about the quality in apparently normal survivors has been increasing as well. The current flood of papers on these subjects illustrates the interest in these issues. The first part of this paper reviews the methodology used in follow-up studies in the past decades. It aims at methodological problems that hamper comparison between studies and preclude unequivocal conclusions. New treatment techniques seldom were but should be evaluated by randomised trials. To monitor the combined effects of changing obstetric and neonatal techniques on perinatal outcome, studies in geographically defined populations are recommended using data from early pregnancy until at least preschool age. Comparability of outcomes could be enhanced by international agreement on standardisation of assessment methods and outcome measures. In the second part the results concerning gestational age- and birthweight-specific mortality, impairments and disabilities and the risk factors for such disorders are discussed. Increased survival of even the tiniest infants is clearly established. This increase in survival has not yet been accompanied by an apparent increase in major morbidity. However, many minor impairments are reported, occurring often in combination and predisposing these children to deviations of normal development. Important changes in the manifestation of brain damage appear to occur during development. These findings stress the importance of long-term follow-up studies.

Follow-Up Studies↗
PubMed1992

Transient hypothyroxinaemia associated with developmental delay in very preterm infants.

In 563 surviving very preterm (less than 32 weeks gestational age) and/or very low birthweight (less than 1500 g) infants the relationship between neonatal thyroxine concentration and psychomotor development at 2 years of age (corrected for preterm birth) was studied. A significant association was found between low neonatal thyroxine concentration and a negative score on the three milestones of development. These findings do not support the view that transient hypothyroxinaemia in preterm infants is harmless.

Child, Preschool↗
PubMed1992

Hyperbilirubinemia in low birth weight infants and outcome at 5 years of age.

The collaborative national survey on morbidity and mortality in preterm and small for gestational age infants in the Netherlands enrolled initially 1338 infants born in 1983. The relationship between maximal serum total bilirubin concentration in the neonatal period and neurodevelopmental outcome in the survivors of this cohort was studied. This relationship at the corrected age of 2 years was previously reported. A dose-response relationship between maximal serum total bilirubin concentration and risk of adverse outcome was observed in the 831 surviving children. The present study reassessed the relationship at the age of 5 years in 814 children. There was no significant difference in mean maximal serum total bilirubin concentration between the children with and without a handicap. This was confirmed by logistic regression analysis. After correction for seven suspected confounding factors (gestational age, birth weight, intracranial hemorrhage, ventriculomegaly, seizures, bronchopulmonary dysplasia, and socioeconomic status) the estimated odds ratio was 1.2 (confidence interval 0.89, 1.43) per 50 mumol/L increase of total bilirubin. However, in this analysis an interaction between bilirubin and intracranial hemorrhage was observed. Therefore, the cohort was divided into two groups according to the absence or presence of an intracranial hemorrhage. Logistic regression analysis including four suspected confounding factors (gestational age, ventriculomegaly, seizures, and socioeconomic status) was then again applied. In children who had suffered from an intracranial hemorrhage in the neonatal period the estimated odds ratio was 1.84 (confidence interval 1.08, 3.15) per 50 mumol/L increase of bilirubin. Similar results were obtained treating bilirubin as a categorized exposure. The odds ratio in children without a hemorrhage was 1.05 (confidence interval 0.80, 1.38), probably because of the small number of surviving handicapped children.

Bilirubin↗
PubMed1992

Five-year outcome of preterm and very low birth weight infants: a comparison between maternal and neonatal transport.

OBJECTIVE: To determine the 5-year outcome of very low birth weight infants referred to tertiary perinatal centers. METHODS: This study was part of a Dutch national collaborative survey of 1338 newborn infants younger than 32 weeks' gestation and/or with a birth weight of less than 1500 g born in 1983. Comparisons were made between maternal transport to university hospital perinatal centers versus delivery in local hospitals, and between neonatal transport to these centers versus treatment in local hospitals. For the 252 survivors meeting the entry criteria for this part of the study, adverse outcome at 5 years of age was evaluated by logistic regression analysis, including 26 perinatal risk factors as confounding variables. Outcome variables were disabilities and handicaps at 5 years as defined by the World Health Organization. RESULTS: There were no differences in handicaps and disabilities between infants born after maternal transport and those born in local hospitals. Handicaps and disabilities in neonates transported versus those treated in local hospitals were also not statistically different despite selection bias. CONCLUSIONS: The previously reported decrease in neonatal mortality risk after maternal transfer is not accompanied by an increased risk of adverse outcome for the survivors. In threatening very preterm delivery, maternal transport to a tertiary center is recommended.

Persons with Disabilities↗
PubMed1992

Survivorship analysis in total condylar knee arthroplasty. A statistical review.

Survivorship analysis, which is often encountered in the medical literature, is used to calculate the probability of a certain event, such as failure of a prosthesis, as a function of the time elapsed since an operation. Possible pitfalls in the use of this method are related to the size of the population of patients and the definition of how the outcome is measured. We studied the outcomes of 204 total knee arthroplasties in 165 patients, using six different end-points, in order to illustrate these problems. Survivorship estimates that are cited without confidence intervals have little clinical value.

Adult↗
PubMed1992

Long term success of aortoiliac operation for arteriosclerotic obstructive disease.

The current retrospective study was performed on 747 patients with aortoiliac obstructive disease who underwent reconstructive operation. Unlike many other centers, the University Hospital Leiden has, throughout the years, maintained the strategy of avoiding the implantation of a prosthesis in patients with limited and localized obstructive disease that could readily be treated with an endarterectomy. When a prosthesis was used, it was anastomosed to the femoral artery if a more proximal anastomosis was not feasible. In the present study, the long term outcome of the strategy is evaluated. Three groups of patients were studied--245 patients with moderate claudication, 331 patients with severe claudication and 162 patients with critical ischemia at presentation. Thromboendarterectomies were used in 229 patients (30.7 per cent) and prosthetic reconstructions in 518 patients (69.3 per cent), of which 339 (45.5 per cent) were aortoiliac reconstructions. The perioperative mortality rates were 1.6, 3.0 and 3.1 per cent for the three groups, respectively. Atherosclerotic heart disease was the most common cause of perioperative (30.0 per cent) and late (30.8 per cent) death. Late complications of surgical treatment also contributed significantly to the causes of late deaths (12.1 per cent). Because over-all survival rates in the current series compared favorably with those in other series, the influence of reconstructive operation on late survival was compensated for by a beneficial effect in patients without such complications. Secondary operations for late complications, such as false aneurysms and aortoiliac reobstruction or for progressive obstructive disease, were necessary in 21 per cent of all 727 survivors of the first operation. Actuarial curves with various endpoints--mortality, secondary operation, patency of aortoiliac segments, functional failure, amputation, presence of mild, moderate and severe claudication--were calculated according to the standard method of life table construction. In terms of technical success rates, the results of our surgical technique strategy compared favorably with those reported in other series, in which most patients were treated with aortobifemoral prostheses. The chances of functional failure increased with time, amounting to about 23 per cent at 15 years postoperatively for each group of patients. Comparison of technical and functional success rates showed a significant disparity, which was explained by the effects of collateral blood flow in instances of aortoiliac reobstruction and of progressing femoropopliteal obstructions in instances of open aortoiliac vessels.

Actuarial Analysis↗
PubMed1991

Impairments, disabilities, and handicaps of very preterm and very-low-birthweight infants at five years of age. The Collaborative Project on Preterm and Small for Gestational Age Infants (POPS) in The Netherlands.

The Project On Preterm and Small for gestational age infants (POPS) was started in the Netherlands in 1983 to investigate the relation between prenatal/perinatal factors and mortality/morbidity in very preterm and very-low-birthweight infants. Of the 1338 liveborn infants (less than 32 weeks and/or less than 1500 g) 966 were enrolled in the five-year (chronological age) follow-up programme; 96% of these children were assessed during a home visit. The overall outcome was expressed as impairments, disabilities, and handicaps according to World Health Organisation criteria. Of the assessed children, 13% had a disability and 14% were handicapped, which are much higher frequencies than those found in the general population. Handicaps were due mainly to abnormalities of neuromotor function, mental development, or language and speech development. Compared with the handicap frequency in the same cohort at two years of age, a more favourable outcome at five years of age was seen in 10%, and a less favourable outcome in 7% of the children. The findings show that most of those high-risk children survived without handicap or serious disability at preschool age.

Child, Preschool↗
PubMed1991

Maternal hypertension and very preterm infants' mortality and handicaps.

In a nationwide survey on liveborn very preterm and/or very low birthweight infants in The Netherlands, mortality and handicaps at the corrected age of 2 years were studied in infants born to mothers with or without hypertensive disorders during pregnancy. The neonatal and in-hospital mortality was significantly lower in infants born to hypertensive mothers. In surviving infants, a similar handicap rate was found at the corrected age of 2 years for both groups.

Congenital Abnormalities↗