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G Van Melle

Publications and source records attributed to G Van Melle.

At least 19 recordsLinked to original sources
PubMed2003

Prodromal and early epileptic seizures in acute stroke: does higher serum cholesterol protect?

In a case-control study, patients (n = 43/3,628) presenting seizures <1 week before (n = 6), < or =3 hours after (n = 26), and 3 to 24 hours after (n = 11) a first-ever stroke were studied. On multivariate analysis, they were characterized by lower levels of serum cholesterol (5.86 +/- 0.51 vs 6.34 +/- 0.58; p < 0.0001). Mortality and functional outcome at discharge were not influenced. Early poststroke seizures occur mainly during the critical 3-hour window for thrombolysis. Hypercholesterolemia appears to protect against seizures and cerebral ischemia.

Acute Disease↗
PubMed2001

Risk of falls for hospitalized patients: a predictive model based on routinely available data.

The incidence rate of falls is often used as an indicator of nursing care outcome. Comparing outcome between different settings should, however, make allowance for case mix. To measure the incidence of falls, describe their circumstances and develop a prediction model based on routinely collected data to allow comparison between hospital settings with different case mix. A dynamic population of patients hospitalized over a year in which a case was defined as any accidental fall systematically reported on an ad hoc form. A Swiss university hospital of 800 beds; 634 falls were reported for 26,643 hospitalizations over 236,307 hospitalization days. First fall rates were analyzed using a Poisson regression model with routinely computerized discharge data as independent variables. The incidence rate of first falls was 2.2 per 1000 patient-days. For subsequent falls the rates of incidence increased with the number of falls. Five independent variables played a significant role: age, gender, morbidity predisposition, surgical procedure and length of stay. Two of the interactions between these variables were significant and remained in the model (length of stay with age, morbidity with age). The model offers good medical plausibility and satisfactory predictive performance. The proposed model can be used by national health agencies to compute expected first fall rates accounting for case mix. Hospitals can use these rates for evaluation. Recommendations for measuring, monitoring and assessing fall rates are also given.

Accidental Falls↗
PubMed2001

Sex-dependent variations and timing of thyroid growth during puberty.

Marked changes in thyroid function occur during puberty as an adaptation to body and sexual development. Characteristics of thyroid growth were investigated in 259 healthy adolescents (110 girls and 149 boys), aged 11--17 yr, in an urban area of Switzerland with sufficient iodine supply. The thyroid volume determined by ultrasonography was correlated with chronological age, body weight, body height, cervical circumference, body mass index, and body surface area (BSA). Iodide concentration was measured in urine. The increase in thyroid volume mainly occurred between 11--15 yr (age at maximum thyroid growth rate, 12.5 yr) and was best correlated with BSA in both genders (girls, r(2) = 0.38; boys, r(2) = 0.49). The BSA-related thyroid growth was almost constant throughout puberty in boys and similar in girls up to menarche, but 14.5% larger in girls after menarche (P < 0.01). Percentiles of thyroid volume were lower than WHO reference values despite low normal urinary iodide concentration (median, 0.75 micromol/L). These findings suggest that physiological thyroid growth during puberty is mainly influenced by growth factors involved in somatic development and further modulated by sex steroid secretion profiles. The thyroid growth spurt coinciding with menarche in girls may contribute to a higher incidence of goiter during mid- to late puberty.

Adolescent↗
PubMed2001

[Neurological comorbidity in parkinsonism].

We studied the neurological comorbidity of parkinsonism in 368 consecutive patients from the Lausanne Movement Disorders Registry. Only 6 patients had no neurological comorbidity. We found that 23p.100 of our patients had ischemic strokes, especially large vessel strokes, i.e three times more than in an age-matched control study performed in a recent survey in our country, which is a new finding in contradiction with previous reports mentioning that Parkinson's disease may be a protective factor against stroke. This finding opens new directions for further studies concerning some shared mechanisms in both diseases associated with age. Predominantly tremulous parkinsonism (46p.100) and progressive supranuclear palsy patients (PSP) (40p.100) had the highest prevalence of cerebrovascular disease of all subgroups of parkinsonism, especially lacunar infarcts, which is in accord with a higher frequency of hypertension in these subgroups according to a recent study of ours. Transient ischemic attacks or hemorrhages were not more frequent than in the general population. We did not find a higher frequency of head trauma except for Parkinson's disease, but a trend for a higher frequency of headache and migraine. Brain tumors were more frequent in Parkinson's disease and hydrocephalus and radiculopathies in parkinsonism in general when compared to age-matched populations from the literature. Polyneuropathies were more frequently observed in familial parkinsonism only, but myopathies and cranial neuropathies were not more frequent in our patients. Epilepsy was significantly less frequent in parkinsonism, especially in Parkinson's disease, infectious diseases of the nervous system were rarely encountered, and restless legs syndrome was surprisingly not more frequent than in a normal population. Dementia was associated in 20p.100, but multiple sclerosis is noticeably absent.

Adult↗
PubMed2000

Coexisting causes of ischemic stroke.

BACKGROUND: Coexistence of multiple potential causes of cerebral infarct (MPCI) has been poorly studied. OBJECTIVE: To determine the risk factors, clinical findings, and topographical patterns of patients with at least 2 potential causes of cerebral infarct. DESIGN: Data analysis from a prospective acute stroke registry (the Lausanne Stroke Registry, Lausanne, Switzerland) in a community-based primary care center. RESULTS: Among 3525 patients with first-ever ischemic stroke consecutively admitted to a primary care stroke center, 250 patients (7%) had at least 2 MPCIs, with the following subgroups: large artery disease and a cardiac source of embolism (LAD + CSE) (43%), small artery disease and CSE (SAD + CSE) (34%), LAD + SAD (18%), and LAD + SAD + CSE (5%). Hypertension, cardiac ischemia, and a history of atrial fibrillation predominated in the LAD + SAD + CSE subgroup (P<.001), while cigarette smoking was more prevalent in the LAD + SAD subgroup (P<.05). A decreased level of consciousness and speech disorders were more common in the LAD + CSE subgroup (P<.001). Lacunar syndromes predominated in the LAD + SAD subgroup. Pure motor stroke was the most frequent lacunar syndrome in all subgroups, but sensory motor stroke predominated in the LAD + CSE subgroup (P<.05). The outcome at 1 month was worse in the LAD + CSE and SAD + CSE subgroups (P<.001). Other stroke characteristics and clinical features did not differ significantly between the 4 subgroups of patients with MPCI. CONCLUSIONS: Our findings suggest that MPCIs are uncommon. The most frequent association is LAD + CSE. Topographical patterns of stroke and clinical characteristics in patients with MPCI only rarely allow emphasis of a preeminent cause. Arch Neurol. 2000;57:1139-1144

Aged↗
PubMed2000

Evaluation of the caloric test by combining 3 response parameters.

The slow-phase velocity of nystagmus is one of the most sensitive parameters of vestibular function and is currently the standard for evaluating the caloric test. However, the assessment of this parameter requires recording the response by using nystagmography. The aim of this study was to evaluate whether frequency and duration of the caloric nystagmus, as measured by using a clinical test with Frenzel glasses, could predict the result of the recorded test. The retrospective analysis of 222 caloric test results recorded by means of electronystagmography has shown a good association between the 3 parameters for unilateral weakness. The asymmetry observed in the velocity can be predicted by a combination of frequency and duration. On the other hand, no relationship was observed between the parameters for directional preponderance. These results indicate that a clinical caloric test with frequency and duration as parameters can be used to predict the unilateral weakness, which would be obtained by use of nystagmography. We propose an evaluation of the caloric test on the basis of diagrams combining the 3 response parameters.

Adolescent↗
PubMed2000

Severe disability at hospital discharge in ischemic stroke survivors.

BACKGROUND: Several studies have attempted to identify criteria for predicting functional prognosis after stroke, but often with contradictory results. The purpose of this study was to predict the functional outcome at discharge of first-time stroke patients included consecutively in the Lausanne Stroke Registry. METHODS: We studied 3,628 sequential patients with first-ever stroke who were admitted consecutively to the Centre Hospitalier Universitaire Vaudois. Functional status was evaluated using the Rankin disability scale at discharge. We studied the prognostic value of historical, clinical and instrumental variables related to functional outcome at discharge. The factors studied were age, sex, risk factors, ECG results, occurrence of transient ischemic attacks (TIAs), extension of cerebral infarction, presumed cause of stroke, clinical findings and demographic characteristics. Univariate analysis was performed on each variable by comparing the number of functionally independent with that of dependent patients at the moment of discharge. The significant variables of the univariate analysis were subjected to multivariate analysis with a backward logistic regression procedure to find those with an independent effect on the outcome. RESULTS: A total of 3,156 patients, excluding 117 patients with ischemic stroke who died during hospitalization and 355 with brain hemorrhage, were included; 2,867 patients belonged to the nil, mild or moderate disability groups (modified Rankin score 1-4; functionally at least partially independent patients), while 291 patients belonged to the severe disability group (modified Rankin score 5; functionally dependent patients). The mean duration of stay in hospital of the severe disability group was 31.2 days (SD = 16.2). Multivariate analysis showed that impaired consciousness on admission, limb weakness, progressive worsening, infarct in the superficial and deep territory of the middle cerebral artery, ischemic heart disease and cardiac arrhythmia were predictors of severe disability at discharge. Age was not an independent predictor of poor outcome. Hypercholesterolemia was significantly related to a better outcome. CONCLUSIONS: Some prognostic indicators associated with functional outcome at discharge are available during the first few hours after onset of stroke. This is important for the management of the individual stroke patient and for organizing suitable rehabilitation planning.

Adult↗
PubMed1999

Urinary oxalate and urate to creatinine ratios in a healthy pediatric population.

The purpose of the study was to determine reference percentiles for the urinary (U) oxalate (Ox) and urate (Ura) to creatinine (Cr) concentration ratios in the second morning urine of healthy infants, children, and adolescents. The urinary oxalate and urate to creatinine ratios were determined in the spontaneously voided second morning urine sample. To test reproducibility, two urine samples were analyzed on 2 consecutive weeks in 63% of the subjects. Three hundred eighty-four healthy children (181 girls, 203 boys), aged 1 month to 17 years, from nurseries, kindergartens, and schools of Lausanne, Switzerland, were studied. The 5th and 95th percentiles were determined from the total number of urine samples (627) after confirmation that there was no order effect between repeated measurements and there were no significant sex differences. A nonlinear regression analysis in terms of age was used to smooth the calculated percentiles. In this manner, curves were obtained from which the reference values can be read at any given age. The 95th percentiles decreased with age: for UOx/Cr from 0.175 mg/mg (0.22 mol/mol) at 1 to 6 months to 0.048 mg/mg (0.06 mol/mol) from 7 years and beyond; and UUra/Cr from 2.378 mg/mg (1.6 mol/mol) at 1 to 6 months to 0.594 mg/mg (0.4 mol/mol) in adolescence. We provide 5th and 95th percentile curves for the UOx/Cr and UUra/Cr ratios determined from the second morning urine samples in a large cohort of healthy infants, children, and adolescents. Values were determined by standard analytical chemical techniques and were analyzed by powerful statistical methods. The calculated 95th percentile for the UOx/Cr values fell rather rapidly and reached normal adult values by the age of 7 years, whereas for UUra/Cr, the 95th percentile decreased slowly and stabilized in adolescence.

Adolescent↗
PubMed1998

Validity and reliability in reporting sexual partners and condom use in a Swiss population survey.

OBJECTIVES: To examine the validity and reliability of indicators of sexual behaviour and condom use in annual telephone surveys (n=2800) of the general population aged 17 to 45 for the evaluation of AIDS prevention in Switzerland. METHODS: A test-retest study with additional focused interviews was conducted on a subsample (n=138) of the respondents aged 17 to 22 years. RESULTS: The subsample included more French speaking respondents (OR: 1.7, CI: 1.1-2.5) and more people in a stable relationship (OR: 2.2, CI: 1.5-3-3) than the initial sample but did not differ in any other way, although no data is available on their attitudes towards sex. The reliability of the indicators considered was high: number of lifetime, casual sex partners in the last 6 months and condom use with them, acquisition of a new steady partner during the year and condom use with this partner, condom use at last intercourse. However, the focused interviews raised questions about the validity of some of these indicators, presumably due to imprecise wording of the questionnaire items. Among sexually active respondents, 12.5% (95% CI: 4.7-25.5) of the men included non-penetrative sex in the definition of 'sexual intercourse', but only 1.9% (95% CI: 0.1-10.3) of the women. The propensity for men of counting acts or partners with whom no penetration had taken place in the total reported sex acts or partners was not significantly associated with any socio-demographic variables. In addition, among the 15 respondents who had reported consistent condom use with casual sex partners at interview, 40% (95% CI: 16.3-67.7) admitted at reinterview that sometimes they also had unprotected sex. CONCLUSIONS: The reliability of reports on sexual behaviour and condom use in this Swiss evaluation survey is good. The indicators derived from the annual surveys are robust measures and the monitoring of trends seems to be based on reliable measurement. However, more research is required on the validity of the data.

Acquired Immunodeficiency Syndrome↗
PubMed1998

Large infarcts in the middle cerebral artery territory. Etiology and outcome patterns.

Large supratentorial infarctions play an important role in early mortality and severe disability from stroke. However, data concerning these types of infarction are scarce. Using data from the Lausanne Stroke Registry, we studied patients with a CT-proven infarction of the middle cerebral artery (MCA) territory that covered at least two of three MCA subterritories (deep, superficial anterior [superior] and posterior [inferior] territory). We compared these patients with patients presenting more limited infarction in the MCA territory. Our study group of large MCA (laMCA) infarction contained 208 patients, corresponding to 7.6% of all ischemic infarctions in the Lausanne Stroke Registry. Seventy-two patients had complete infarction in the whole MCA territory (coMCA). Internal carotid artery (ICA) occlusion (41%) and ICA dissection (12%) were more common than in limited superficial MCA (lsMCA) infarct and anterior circulation infarct (p < 0.001). Among the patients without ICA occlusion, atrial fibrillation (33%; p < 0.002) and cardiogenic embolism in general (54%; p < 0.001) were more frequent in laMCA than in lsMCA infarct. Severe neurologic deficit (hemiplegia and hemisensory loss in the face, arm and leg, hemianopia, global aphasia, reduced consciousness) was more common than in other types of infarct. A combination of these symptoms had a positive predictive value for laMCA infarction of 0.73 (sensitivity for left side laMCA infarcts, 0.56). Mortality (17%) and severe disability (50%) were higher with laMCA than for other infarcts (p < 0.001). Sixteen of the 35 deaths could be attributed to brain edema. Reduced consciousness, hemianopia, and coMCA infarction were independent predictors of death or severe disability; for death only, coma was an independent predictor. Patients who died because of brain edema were younger than patients whose death was due to other causes (mean age, 57 versus 73 years; p < 0.001); they also died sooner (mean time of death after stroke, 5 versus 37 days; p < 0.001). Furthermore, patients who developed coma on the day of admission were more likely to die because of brain death (p < 0.001). Large middle cerebral artery infarction is associated with cardiogenic embolism, ICA occlusion, and ICA dissection. It is a major predictor of death and severe disability, although a lower frequency of malignant brain infarction was found than previously reported.

Adolescent↗
PubMed1997

Propranolol as an adjunct therapy for hyperthyroid tremor.

We evaluated the use of propranolol as an adjunct to carbimazole in the treatment of hyperthyroid tremor and tachycardia in a double-blind, cross-over and placebo-controlled study. Seven patients were given carbimazole plus either placebo or propranolol (40 mg) for 1 month and then switched to the alternative adjunct treatment for a further month. All patients showed significant improvements (p < 0.001) of heart rate and tremor amplitude after 1 or 2 months from baseline. One month after the baseline, the mean improvements of heart rate were 23% for the carbimazole + placebo group and 38% for carbimazole + propranolol group. Tremor also improved during the 1st month of the study by 31% in the carbimazole + placebo group versus 59% in the carbimazole + propranolol group. Whereas further improvements were observed in both variables in those receiving propranolol as the second adjunct treatment, this was not the case in those who received placebo during the same period. These findings confirm that the beta-blocker propranolol is a useful adjunct in the early treatment of both the tremor and tachycardia of hyperthyroidism.

Adrenergic beta-Antagonists↗
PubMed1997

Prognostic factors associated with loss of heterozygosity at the RB1 locus in retinoblastoma.

The nature of the tumorigenic mutation was analyzed in 30 retinoblastoma (Rb) tumors (16 non-hereditary and 14 hereditary) and categorized into loss of heterozygosity (LOH) or retention of heterozygosity (non-LOH) at the RB1 locus. These genotypic characteristics were compared with the clinicopathological phenotype for possible correlation. The overall frequency of LOH was roughly 55%, in both hereditary and non-hereditary Rb. The presence of LOH was preferentially associated with differentiated tumors and absence of choroidal invasion. LOH was found in 82% of females versus 33% of males. Finally, LOH-initiated tumors were associated with a significantly younger age at diagnosis in hereditary Rb. In conclusion, the preferential association of LOH with absence of choroidal invasion, tumoral differentiation, and younger age at diagnosis may establish LOH as a prognostic marker in Rb patients.

Biomarkers, Tumor↗
PubMed1996

Botulinum toxin A in non-dystonic tremors.

The present pilot study evaluated the effect of botulinum toxin A on primarily non-dystonic tremors using accelerometry in a single-blind, placebo-controlled design. Resting, postural, intention, or head tremor were assessed before and approximately 1 month after intramuscular saline and botulinum toxin A (25-50 U) respectively. Half of the patients showed > or = 30% placebo effect. Tremor in 10 of 17 patients (60%) studied improved further after botulinum toxin A (range 30-95%), exceeding the placebo effect by > or = 30%. Nine patients demonstrated clinically significant focal weakness in the extensor muscles after botulinum toxin A which interfered with fine movements. Patients were subdivided into PD-like and ET-like tremor(s). Both groups experienced large placebo effects for resting tremor, with little or no further improvement after botulinum toxin A. The improvement in postural tremor after botulinum toxin A, of 40% in the PD-like and 57% in the ET-like groups, however, was approximately twice that of placebo. In conclusion, botulinum toxin A exerts a modest tremorlytic effect, however the dose, and its distribution over the sites injected, need to be optimised to minimise focal weakness.

Adult↗
PubMed1996

Stroke recurrence in patients with patent foramen ovale: the Lausanne Study. Lausanne Stroke with Paradoxal Embolism Study Group.

Patent foramen ovale (PFO) is more common in patients with stroke than in matched controls, but the stroke mechanism and late prognosis are not well known. We studied features, coexisting causes, and recurrences of stroke in 140 consecutive patients (mean age 44 +/- 14 years) with stroke and PFO admitted to a population-based primary-care center. We selected the patients from 340 patients (41%) aged < or = 60 years with acute stroke. The initial event was brain infarction in 118 patients (84%) and TIA in 22 (16%). Intracranial embolic occlusions were present on angiography or transcranial Doppler in most patients admitted within 12 hours of onset, whereas a venous source was clinically apparent in only six patients (5.5%). Pulmonary embolism, Valsalva maneuver at onset, and coagulation abnormalities were rare, but one-fourth of the patients had an interatrial septum aneurysm (ISA) that coexisted with PFO. An alternative cause of stroke was present in only 22 patients (16%), usually cardiac (atrial fibrillation, severe mitral valve prolapse, akinetic left ventricular segment). During a mean follow-up of 3 years, the stroke or death rate was 2.4% per year, but only eight patients had a recurrent infarct (1.9% per year). This low rate of recurrence contrasted with the severity of initial stroke, which left disabling sequelae in one-half the patients. Multivariate analysis showed that interatrial communication, a history of recent migraine, posterior cerebral artery territory infarct, and a coexisting cause of stroke were associated with recurrence, whereas ISA and treatment type (coagulant or antiaggregant therapy, surgical closure of PFO) were not. However, given the low number of events, these findings must be taken with caution. In conclusion, our study shows that stroke associated with PFO with or without ISA is not commonly due to a coexisting cause of stroke. It is usually embolic, although a definite source cannot often be demonstrated. The presenting stroke is often severe, but recurrence is uncommon. The demonstration of factors associated with a higher risk of recurrence in subgroups of patients is critical for the long-term management of these patients.

Adult↗
PubMed1995

Surgery in native valve endocarditis: indications, results and risk factors.

Seventy-nine patients (mean age 49 years) underwent valve replacement or repair for active (58.2%) or healed (41.8%) native valve endocarditis between 1976 and 1992. The most common indication for surgery was congestive heart failure (73.4%), followed by multiple systemic emboli (21.5%). Emergency operation was necessary in 27.8% of the cases. Operative mortality was 3.8% (3 patients) and late mortality 15.1% (12 patients). Streptococci were the most common infecting agents (41.8%), followed by Staphylococcus aureus (11.4%). No organisms were isolated in 27 cases (34.2%). Follow-up spanned 379.8 patient-years with a maximum of 15.8 years. Fifteen late valve-related events (periprosthetic leak, recurrent endocarditis, thrombo-embolic events and hemolysis) and 20 other late complications (anticoagulant-related hemorrhage, arrhythmias or congestive heart failure) occurred in 22 patients. The linearized rate for all late complications is 5.8% per patient-year. The influence of eight preoperative variables on overall mortality and late valve-related complications was assessed: age, valve(s) affected, active or healed infection, bacteriology, annular abscess, emergency or elective surgery, preoperative renal function and NYHA class. Only Staphylococcus aureus (P = 0.0012) was a significant predictor of late valve-related complications. Furthermore, no difference in survival or in valve-related complications was found between the active and healed infections.

Actuarial Analysis↗
PubMed1995

Headache at stroke onset: the Lausanne Stroke Registry.

Within 12 hours of stroke onset 2506 patients with first ever stroke admitted to the Lausanne Stroke Registry were questioned about headache. Eighteen per cent of the patients reported headache, 14% with anterior circulation stroke and 29% with posterior circulation stroke (p < 0.001). Headache was reported by 16% of the patients with infarct and 36% of those with haemorrhage (p < 0.001). The prevalence of headache was 9% with lacunar infarct, 15% with middle cerebral artery territory infarct, 37% with infratentorial haemorrhage, and 36% with supratentorial haemorrhage. The most common topography of pain was frontal (41%), followed by diffuse headache (27%; p < 0.001). Diffuse (41%) or occipital (30%) headache was particularly frequent with posterior circulation stroke, whereas frontal headache was associated with anterior circulation stroke (51%; p < 0.001). Headache in stroke may be explained in part by involvement of blood vessels (acute distention or distortion) and mechanical (stretch of haemorrhage) stimulation of intracranial nociceptive afferents. Stroke due to dissection was strongly associated with headache (p < 0.001), whereas embolic (cardiac, artery to artery) stroke was more common without headache (p < 0.001), emphasising the role of extracranial v intracranial arteries in the genesis of headache at stroke onset. Moreover, dual trigeminal-vascular and cervical-vascular system involvement in causing headache may explain the lack of correspondence with the "rules of referral" in up to 38% of the cases.

Adolescent↗
PubMed1994

Bacteremia due to viridans streptococcus in neutropenic patients with cancer: clinical spectrum and risk factors.

Between 1988 and 1991, 26 episodes of bacteremia due to viridans streptococci occurred in 25 neutropenic patients undergoing intensive chemotherapy for hematologic malignancies. Complications related to the bacteremia were observed in 10 episodes: unilateral pulmonary infiltrates (4), acute respiratory distress syndrome (ARDS) (4), hypotension (3), and endocarditis (2). All patients with ARDS had received high doses of cytosine arabinoside and had bacteremia due to Streptococcus mitis. Death occurred in three patients (12%) but was possibly related to bacteremia in only one case. Case patients who had received prophylaxis with quinolones were compared with matched control patients who received similar prophylaxis but who did not have bacteremia due to viridans streptococci. Multivariate analysis of predisposing factors showed that high doses of cytosine arabinoside (P = .01), the presence of mucositis (P = .02), and the absence of previous therapy with parenteral antibiotics (P = .01) were independent risk factors for the development of viridans streptococcal bacteremia. Of 259 patients who had received quinolone prophylaxis during the study period, 22 (8.5%) developed an episode of viridans streptococcal bacteremia as compared with three episodes (3.7%) in 82 patients who had received a quinolone and penicillin (P = .07). However, the latter three episodes were caused by strains with decreased susceptibility to penicillin, thus suggesting that resistance to penicillin might limit the use of this antibiotic as a prophylactic agent in the future.

4-Quinolones↗