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A S Luís

Publications and source records attributed to A S Luís.

At least 19 recordsLinked to original sources
PubMed2001

[Can blood homocysteine explain the family history of vascular diseases?].

INTRODUCTION AND AIMS: Family history of vascular disease is an important risk factor for vascular disease, independent of conventional risk factors. Homocysteinemia, a newly defined risk factor, is caused by genetics, such as cystathionine beta synthase deficiencies, and metabolic deficiencies. With the present work we intend to study the influence of family history of vascular disease in homocysteinemia. METHODS: We studied 204 normal persons (153 males), average age 38.7 +/- 10.9 years, in terms of family history of vascular disease (death due to myocardial infarction or a stroke), conventional risk factors, routine laboratory tests, fasting homocysteinemia and after oral methionine loading (0.1 g/Kg body weight). We compared laboratory results, conventional risk factors and homocysteinemia levels in persons with and without a family history of vascular disease. We performed covariance analysis to evaluate, in a multivariate model, factors that were related to basal or after methionine loading homocysteinemia. RESULTS: 35% of persons presented a family history of vascular disease (FHVD). Persons with FHVD presented higher age (45.6 +/- 8.9 versus 35.0 +/- 10.1, p < 0.001), and higher prevalence of hypertension (p = 0.002), dyslipidemia (p = 0.001), obesity (p = 0.03), and physical inactivity (p = 0.03). They presented a tendency, without statistical significance, to have a higher prevalence of diabetes and of hyperhomocysteinemia, and to present higher levels of basal and afterload homocysteinemia. Performing covariance analysis, basal homocysteinemia did not present any relation to FHVD. After methionine load homocysteinemia was strongly influenced by basal homocysteinemia (p = 0.0000), and significantly related to FHVD (p = 0.039). CONCLUSIONS: Homocysteinemia cannot explain most of the risk of family history of vascular disease, not explained by conventional risk factors. The only significant relationship between homocysteinemia and FHVD was observed with afterload homocysteinemia in the multivariate model. FHVD is clearly related to conventional risk factors.

Adult↗
PubMed2001

[Homocysteine].

Explore the source record for details and available documents.

Arteriosclerosis↗
PubMed2000

[Influence of smoking on homocysteinemia at baseline and after methionine load].

INTRODUCTION AND AIMS: Homocysteinemia (HC) and smoking are both important risk factors for vascular disease. In the present study, we intend to evaluate the influence of smoking habits on HC values as well as on vitamins B6, B12 and folic acid, co-factors of HC metabolism. METHODS: We measured fasting homocysteinemia (basal) and homocysteinemia 6 hours after an overload with 0.1 g methionine/kg body weight in 279 subjects. We also performed the dosage of plasma levels of B6 and B12 vitamins and of red cells folates. Smoking habits were inquired and the subjects were classified as non-smokers, current smokers or ex-smokers (if they had stopped smoking more than 1 month before the study). According to the smoking status, smokers were classified in three groups: less than 20 cigarettes a day, between 20 and 39 and 40 or more cigarettes a day. We studied basal and after methionine load homocysteinemia, B6, B12 and folic acid levels in each group. RESULTS: Smokers presented significantly higher levels of basal and after methionine load homocysteinemia then non-smokers (10.6 +/- 4.9 vs 9.4 +/- 2.6, and 26.8 +/- 10.0 vs 24.3 +/- 7.4 mumol/L, respectively, p < 0.05 for both and B6 levels (29.2 +/- 12.0 versus 32.6 +/- 12.0 mumol/L, p < 0.05). B12 and folic levels were similar in the two groups. These results were quite similar either in the normal subjects or in the subjects with a history of a cardiovascular event. The subjects who smoked 40 or more cigarettes per day, compared with those who smoked less then 20 cigarettes per day, presented higher levels of basal homocysteinemia (12.4 +/- 2.9 vs 10.0 +/- 5.5 mumol/L, p < 0.05) and lower levels of B6 (24.7 +/- 8.1 vs 31.7 +/- 12.6 mumol/L, p < 0.05). CONCLUSIONS: Smoking habits are related with the increase of basal and after methionine load homocysteinemia, probably because of a decrease in B6 vitamin levels. There is a proportional effect between the number of cigarettes smoked, B6 depletion and basal homocysteinemia increase. This study suggests that B6 vitamin supplements for smokers could decrease the vascular risk related with smoking habits.

Adult↗
PubMed2000

[Diastolic dysfunction and left ventricular hypertrophy in familial amyloidotic polyneuropathy: a cause-effect relationship?].

UNLABELLED: TTR Met30 Familial Amyloidotic Polyneuropathy of the Portuguese type (FAP) is an incapacitating and lethal hereditary disorder that affects predominantly young adults of both genders. Portuguese type FAP patients have sensory, motor and autonomic polyneuropathy. The generalised systemic amyloid infiltration involves the heart, leading to the characteristic granular bright sparkling echocardiographic pattern. LV wall thickening occurs in the late phases of the disease. LV diastolic dysfunction has been reported in the absence of systolic dysfunction; an abnormal diastolic transmitral flow pattern assessed by pulsed wave Doppler (PW) was described. PW is very much dependent on load conditions. Tissue Doppler imaging (TDI) has been used as a more reliable method to assess long axis diastolic function. OBJECTIVE: 1--To identify the incremental value of TDI in the assessment of diastolic function in FAP. 2--To correlate diastolic pattern abnormalities and left ventricular mass index (LVMI) in FAP patients. METHODS: We performed a prospective evaluation of 24 consecutive FAP patients and selected 14 (sinus rhythm, age < 45 years). Diastolic function was assessed by PW and classified as normal (GI-E/A > 1) or abnormal (GII-E/A < 1). TDI was performed in 4 sites of the mitral annulus (septum, lateral, inferior, anterior). Velocities of the rapid filling wave (E') and atrial contraction wave (A') were measured and E'/A' calculated. In each site we considered the TDI as normal (E'/A' > 1) or abnormal (E'/A' < 1). The LVMI was calculated by Devereux's formula. RESULTS: Age, gender and heart rate were similar in both groups. TDI at the septal mitral annulus was normal in all of the GI patients (E'/A': 1.29 +/- 0.19) and suggestive of abnormal LV relaxation in all of the GII patients (E'/A': 0.82 +/- 0.11, p < 0.0001). TDI revealed abnormal diastolic pattern when a restricted number of sites of the mitral annulus were assessed, even in GI patients and before PW abnormalities occurred. Fractional shortening (FS) and LVMI were similar in GI and GII (FS-GI: 45.5 +/- 5.3, GII 43.5 +/- 8.1%, p: NS; LVMI--GI: 66 +/- 9.3, GII: 67 +/- 3.0 g/m2 p: NS). CONCLUSION: The assessment of mitral annulus motion has introduced new data in the study of diastolic function of FAP patients. An abnormal LV relaxation pattern occurred early in the evolution of the disease in patients with normal LVMI and systolic function.

Adult↗
PubMed2000

[Prognosis significance of blood homocysteine after myocardial infarction].

INTRODUCTION AND AIMS: Homocysteinemia is an independent risk factor of coronary artery disease and of myocardial infarction. In the present study we intend to relate fasting homocystein levels to prognosis after a myocardial infarction. METHODS: From 1990 to 1992, we studied fasting homocysteinemia levels on a group of 112 patients aged under 56 years that had suffered a myocardial infarction between 3 and 12 months before. We obtained, the patients names, addresses, phone numbers and physicians' name. Seven years later (on average) we collected data regarding the patients evolution, consulting medical records, their physicians or by personal contact. We evaluated complications, namely mortality, vascular morbidity, such as unstable angina, re-infarction, stroke, and the need for invasive procedures (catheterism, PTCA, CABG). According to previous studies of the group, we used a cut-point of 10.10 mumol/L to define patients with normal or pathological levels of homocysteinemia. We excluded all patients that took vitamin B supplements, co-factors of HC metabolism, during this follow-up. RESULTS: We were able to obtain data on 110 patients. Patients with normal HC levels (n = 62) presented less global complications (26 versus 72%, p < 0.0001), non significant tendency to have lower mortality (1.6 versus 6%), had lower morbidity (14 versus 36%, p < 0.01) and lower invasive procedure need (18 versus 48%, p < 0.001). In the group with pathological homocystein levels (n = 48), those with higher homocystein levels presented a higher degree of complications. CONCLUSIONS: In this population with myocardial infarction under 56 years of age, a high homocysteinemia level is an important prognostic factor. This study suggests that we can improve the prognosis and decrease the complications after myocardial infarction by lowering elevated homocystein levels.

Homocysteine↗
PubMed1999

[The effect of sex and menopause on basal blood levels of homocysteine and after methionine loading].

INTRODUCTION AND OBJECTIVES: We have already proved that basal and after load homocysteinemia are risk factors for vascular disease and it is also known that premenopausal women are relatively protected against this disease. The objective of this paper was the assess whether there are any differences in the plasma levels of homocystein which might contribute to explain the differences in the incidence of vascular diseases found in both sexes. PATIENTS AND METHODS: Two hundred and four patients (153 males) without previous vascular disease were enrolled in the study. These patients were participating in a screening program for cardiovascular risk factors in a central hospital in Lisbon. We evaluated the basal homocysteinemia and homocysteinemia 6 hours after an oral load with methionine (0.1 g/kg body weight). Basal and after load homocysteinemia in men and women, as well as in women before and after menopause, was compared. Because homocysteinemia does not have a normal distribution, we used non-parametric statistical tests, namely the Mann-Whitney test. RESULTS: Men had higher values for basal homocysteinemia than women (mean and standard deviation)--9.64 +/- 3.15 versus 8.56 +/- 2.82 mumol/l, (p = 0.0018)--as well as for after load homocysteinemia--24.40 +/- 7.84 versus 23.71 +/- 10.16 mumol/L, non significant difference. Premenopausal women (n = 42) had lower basal homocysteinemia values than post menopausal women (n = 9)--8.41 +/- 3.02 versus 9.23 +/- 1.38 mumol/L, p < 0.05--and similarly after load homocysteinemia values--23.86 +/- 10.65 versus 23.01 +/- 7.47 mumol/L. CONCLUSIONS: Basal homocysteinemia is significantly higher in men than in women. After menopause, basal homocysteinemia levels increase significantly in women, approaching those in men. The levels of after load homocystein are not dependent on sex or pre- or postmenopausal condition. Homocysteinemia might explain, at least partly, the differences in the incidence of vascular disease in both sexes and the increased vascular risk in postmenopausal women.

Administration, Oral↗
PubMed1999

[Homocysteinemia and vascular disease--a new risk factor is born].

In recent years there has been growing evidence that high levels of plasmatic homocysteine constitute an independent risk factor for early cardiovascular disease. In this article we review the main theories of atherosclerosis which take into account the proteins, namely homocysteine, homocysteine metabolism, the cause that may be responsible for high levels of homocysteinemia, the pathophysiologic mechanisms of vascular lesion induced by hyperhomocysteinemia, the clinical evidence that homocysteinemia constitutes a vascular risk factor and finally, the evidence that it is possible to control homocysteinemia with supplementation of co-factors of homocysteine metabolism, namely vitamin B6, B12 or folic acid.

Arteriosclerosis↗
PubMed1998

[Myocardial viability. Concept, physiopathology. Methods and diagnostic value].

The purpose of this study is to describe the concept and physiopathology of myocardial viability to provide rational use of diagnostic methodologies and their value. Great relevance has been given to the diagnosis of myocardial viability since it was published in 1982, because of the consequences of therapeutic decisions and prognostic evaluation on the patient's quality of life. The cost/benefit values of these methodologies must be adequate in clinical terms and carefully assessed.

Echocardiography↗
PubMed1995

[Severe poisoning by organophosphate compounds. An analysis of mortality and of the value of serum cholinesterase in monitoring the clinical course].

Ingestion of organophosphate (OP) compounds usually results in severe poisoning. We undertook a retrospective study of 52 consecutive patients admitted with severe OP poisoning to determine the value of serum cholinesterase (SChE) in monitoring clinical course. Considering survivors and non-survivors, we evaluate clinical and laboratory baseline characteristics, severity scores (APACHE II, SAPS II), atropine rate (mg/h), SChE evolution at 24, 72 and 120 h and final SChE (SChE at the day of discharge or death). Mortality in the ICU was 28.9% (n = 15). In both groups SChE showed a trend to increase. In survivors, SChE recovery was statistically significant for SChE 24h-SChE 72 h, SChE 24 h-SChE 120 h and SChE initial-SChE 120 h (p = 0.008, p = 0.00003, p = 0.0002 respectively). In this group a simultaneous decrease in atropine requirements was registered. In non-survivors, the rate of atropine remained unchanged up to 120 h. Three groups could be defined in non-survivors according to their final SChE and day of death. Non-survivors-1 (death in the first 24h; 2 patients) and non-survivors-2 (death after the first 24 h; 5 patients) had a final SChE below 10% of normal SChE activity and statistically different from survivors' final SChE. Non-survivors-3 (8 patients) had a final SChE similar to the survivors and death was due to sepsis and multiple organ failure (MOF). We conclude that SChE is useful in OP poisoning diagnosis and also in monitoring clinical course. SChE recovery above 10% of normal seems to correlate with good prognosis. Sepsis and MOF were important determinants of mortality.

Acute Disease↗
PubMed1994

[Homocysteinemia as a risk factor in early cerebrovascular disease].

PURPOSE: To determine whether hyperhomocysteinemia represents a risk factor of early thrombotic cerebrovascular disease. METHOD: In a group of patients under 55 years of age (n = 33, 19 males) which had suffered a stroke from 3 months to 1 year before the study, defined by clinical criteria and presence of cerebral infarction confirmed by tomography, without history or predisposition to embolic disease. The patients were matched with a group of normal controls of checkup program, in terms of age, and sex. Patients and controls with a history of alcoholism, clinical or laboratory signs of renal or hepatic insufficiency or with a history of recent ingestion of Group B vitamins were excluded since these conditions would influence homocysteinemia levels. We measured the plasmatic basal homocysteinemia of patients and controls (HC) and 6 hours later a methionine overload of 0.1 g/Kg body weight (LOAD HC). RESULTS: Patients; Controls; Signific.; Age 46.0 +/- 7.7; 45.9 +/- 7.8; NS; Basal HC. 10.1 +/- 3.4; 8.5 +/- 1.7; p < 0.05; Load HC 28.0 +/- 7.6; 22.7 +/- 5.5; p < 0.01. CONCLUSION: In this study hyperhomocysteinemia appears as a risk factor for thrombotic cerebrovascular disease before the age of 55;-The measurement of homocysteinemia after the methionine loading test was more discriminative than the basal measurement;-A larger number of patients and controls will be necessary to establish the relative importance of homocysteinemia among other vascular risk factors in cerebrovascular disease.

Adult↗