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PubMedDate not supplied

[Administrative data as source for epidemiological research: clinical pathways of diabetic patients].

UNLABELLED: Objectives 1. To assess if record linkage of two different databases could improve the quality and understand the epidemiology of diabetes and its complications. 2. To analyse how hospitalization relates to the natural history of the disease and to its pharmaceutical management. 3. To document how pharmacoepidemiology could be a challenging tool for clinicians. 4. To identify critical areas where improvement of care would be specifically important. METHODS: Data came from two large databases, the drugs prescription and the hospital discharge forms of the Local Health Unit of Rovigo, Italy, collected through 2000. A casecontrol design was adopted to compare two cohorts identified by prescription of antidiabetic vs any other drugs and the linkage to their hospitalizations over the index period. The study was focused on people > or = 50 year in order to concentrate the attention on NIDDM. A population of 5.603 patients were identified as diabetic and 63.155 were the controls. The prevalence of diabetes was 3.6% in the general population and 8.1% in 50 year and older. The hospitalizations analysis revealed differences between cases and controls in term of longer duration of stay (10.1 vs 8.4 days), higher in-hospital mortality (5.5% vs 5%) and higher presence of cardiovascular complications. Of the 2.922 hospitalizations registered for diabetics, 43% did not report the specific ICD-9-CM code for diabetic disease (250.x). Record linkage of these administrative databases offers new opportunities to improve the comprehension of the natural history of diabetic disease. The identification of diabetic patients from prescription data allows a more reliable picture of the hospitalization than the simple analyses of hospital discharge forms. Up to 43% of hospitalizations in the diabetic cohort did not report the specific diabetic disease diagnosis, compared to the 25% reported in a previous observation where linkage was not applied. The lack of this code registration during hospitalization can reflect a scant perception of the importance of diabetes as the major determinant of complications and could open a discussion table with other clinicians, general practitioners and health care professionals.

Age Factors↗
PubMed1989

[Effect of isoproterenol on left-ventricular systolic time interval in primary hypertrophic cardiomyopathy].

Left ventricular systolic time intervals were investigated before and after administration i.v. 10 micrograms of isoproterenol in a group of 12 patients with hypertrophic cardiomyopathy. Control group consisted of 10 healthy subjects. Isoproterenol shortened on hypertrophic cardiomyopathy pre-ejection periods: pre-ejection period index, isovolumetric contraction time, and Q-1. sound interval. Q-2. sound interval index did not shorten after isoproterenol what was observed in healthy subjects. Lef ventricular ejection time index lengthened little in patients and shortened in controls. These changes of left ventricular systolic time intervals suggest that isoproterenol makes difficult blood ejection from the ventricle.

Adult↗
PubMed1986

Early improvement of left ventricular function during caloric restriction in obesity.

Left ventricular function (LVF) was studied in 25 obese patients (four males and 21 females) by serial poligraphic measurements, namely systolic time intervals (STI), during a short period of dieting (2721 kJ/day (650 kcal/day) as single daily meal regimen). In the same period, all the patients underwent also three standardized exercise tests at the cycloergometer. At the end of the study (20th day), statistically significant differences were obtained in weight loss (P less than 0.001); two main parameters of STI, namely pre-ejection period index (PEPI) and PEP/LVET ratio were lowered (P less than 0.001): furthermore, peak and recovery systolic blood pressure (SBP) and heart rate (HR) during exercising, were also significantly reduced. These data suggest that an improvement of LVF and cardiac performance are present since the early phases of caloric restriction in obesity.

Adolescent↗
PubMed1985

Bancroftian filariasis and malaria in island and hinterland populations in Sabah, Malaysia.

An epidemiological survey of filariasis and malaria in Banggi Island and Upper Kinabatangan, Sabah, revealed microfilarial rates of 7.2% and 8.6% respectively and malaria prevalence of 9.7% and 16.9% respectively. Wuchereria bancrofti was a rural nocturnally periodic type with a periodicity index of 137.2 and average peak hour at 01.32 hrs; 9.2% of microfilaremic carriers as compared to 2.4% amicrofilaremic subjects had clinical filariasis. The Plasmodium falciparum: P. vivax: P. malariae ratios were 1:1:0.17 and 1.4:1:0.12 for Banggi and Upper Kinabatangan respectively. Anopheles flavirostris was incriminated as a new malaria vector in Banggi where the well-known primary malaria vector is An. balabacensis. The latter was also found for the first time to be a vector of rural W. bancrofti in Upper Kinabatangan. Experimental feeding also showed that L3 larvae of W. bancrofti were recovered at low rates from An. balabacensis. Aedes togoi appeared to be a suitable laboratory vector for W. bancrofti.

Adolescent↗
PubMed1985

Systolic time intervals before and after haemodialysis.

We investigated changes of haemodynamics during haemodialysis in 107 patients by noninvasive measurement of systolic time intervals. Heart rate and preejection period index increased and systolic and diastolic blood pressure, left ventricular ejection time and isovolumic contraction time decreased. We found, that if the pre-dialysis ejection fraction (EF) was more than 55 per cent, post-dialysis EF decreased by about 10 per cent. However if pre-dialysis EF was less than 55 per cent, post-dialysis EF increased by five per cent. Regarding cardio-thoracic-ratio, Sokolow-Lyon-Index (SLI) and repolarisation disorders we found the most remarkable decrease in EF in patients with normal sized hearts with enlarged SLI and repolarisation disorders.

Adult↗
PubMed1984

Non-invasive evaluation of the haemodynamic effects of amiodarone.

Sixteen patients were examined hemodynamically with echocardiography, calibrated apexcardiography, and systolic time intervals before treatment, after 1 week treatment with amiodarone 600 mg daily and after 2-4 months treatment with 300 mg daily. During the treatment thyroid function was controlled. The echocardiogram showed a small increase in shortening fraction, while left ventricular dimensions did not change significantly. The apexcardiogram revealed minor changes, which could not be interpreted as being due to changes in contractility. The systolic time intervals showed marked decreases in preejection period index and preejection period/left ventricular ejection time. These changes could not be correlated to changes in serum thyroxine, which was the only thyroid parameter to change significantly. The hemodynamic changes during amiodarone treatment were interpreted as mainly being due to a decrease in afterload while possible changes in preload and myocardial contractility were of minor importance.

Adult↗
PubMed1984

The influence of a therapeutic dose of nitroglycerin on invasive and non-invasive parameters of left ventricular performance in coronary heart disease.

To assess the influence of a therapeutic dose of 0.5 mg sublingual nitroglycerin (NTG) on left ventricular performance, 32 patients with coronary heart disease were studied. After routine coronary angiography the patients underwent cinearteriography and phonomechanocardiography before and four minutes after NTG administration. After NTG, end-diastolic pressure and systolic aortic pressure fell significantly, while heart rate, ejection fraction and dp/dt increased. After NTG, a significant prolongation of the pre-ejection period index (PEPI) and isovolumetric relaxation time (IVRT), increase in the PEP/LVET ratio and decrease of the "a" wave of the apexcardiogram were found. The usual therapeutic sublingual NTG dose causes profound haemodynamic changes which are due to decreased preload and afterload and altered contractility induced by NTG.

Cardiac Output↗
PubMed1983

The use of systolic time intervals in the evaluation of antihypertensive treatment with metoprolol, labetalol and prazosin.

26 patients with moderate hypertension and no signs of heart failure were treated with metoprolol, labetalol or prazosin. Systolic time intervals (STI) were measured before and after several months of treatment. During treatment with metoprolol, a decrease in the preejection period index (PEPI), and preejection period/left ventricular ejection time ratio (PEP/LVET), was found. During treatment with labetalol or prazosin, a minor decrease in PEPI was observed, so that a significant decrease in PEP/LVET was not obtained. A decrease in PEPI and PEP/LVET may be due to improved cardiac performance, but in the given type of patients it is more dependent on the reduction in afterload. The STI measurement is less sensitive in discerning different mechanisms involved in lowering the blood pressure and cannot therefore be used for selecting the optimal antihypertensive drug.

Adult↗
PubMedDate not supplied

Systolic time intervals in hyperthyroidism.

PEPI (pre-ejection period index), QS2I (total electromechanical systolic index), LVETI (left ventricular ejection time index), and PEP/LVET ratio were measured in 35 thyrotoxic patients. None of the patients had clinical evidence of heart disease nor received drugs which might have affected the systolic time intervals. the hyperthyroid subjects showed significant shortening of PEPI and significant reduction of PEP/LVET, which returned within normal limits when the patients became euthyroid during treatment. No correlation could be found between T3, T4, FTI and PEPI or PEP/LVET. However, serial measurements indicated that the fall toward the normal range of PEPI parallelled that of T3; the latter is considered the most important index of thyroid function. Our study suggests that PEPI and PEP/LVET ratio may be of great usefulness in detecting hemodynamic alterations in subjects with uncomplicated hyperthyroidism. Moreover, these methods may facilitate the diagnosis in unusual types of hyperthyroidism occurring in the absence of clinical signs of toxicosis. In addition, PEPI and PEP/LVET appear to be useful in detecting T3 toxicosis. Finally, serial controls of PEPI could represent a useful index to monitor the response to therapy.

Adolescent↗
PubMed1996

[Immediate hemodynamic response to atrioventricular+ stimulation in severe hypertrophic obstructive myocardiopathy].

INTRODUCTION AND OBJECTIVES: Atrial synchronized ventricular pacing has shown to be an alternative to surgery in the therapeutic management of obstructive hypertrophic cardiomyopathy. Our purpose is the analysis of the hemodynamic mechanisms associated with the reduction of left ventricular outflow tract gradient and the changes in left ventricular diastolic function induced by dual-chamber pacing. PATIENTS AND METHODS: We studied twenty patients (age range 40-78 years; mean 63 +/- 10), who were evaluated while receiving their current medication with cardiac catheterization and angiography, at baseline and under dual-chamber pacing. RESULTS: The atrioventricular delay was 127 +/- 26 ms. The subaortic gradient was reduced from 96 +/- 38 to 36 +/- 28 mmHg (p < 0.001), the ejection period index was shortened from 523 +/- 26 to 491 +/- 30 ms (p < 0.001) and the left ventricular end-diastolic pressure fell from 22 +/- 6 to 13 +/- 5 mmHg (p < 0.001). There was no remarkable change in cardiac output. The median wedge pressure decreased from 17 +/- 5 to 12 +/- 2.5 mmHg (p < 0.01), the pulmonary systolic pressure from 39 +/- 15 to 30 +/- 10 mmHg (p < 0.01), the pulmonary diastolic pressure from 19 +/- 5 to 13 +/- 4 mmHg (p < 0.01) and the right ventricular end-diastolic pressure from 7 +/- 3 to 5 +/- 3 mmHg (p < 0.05). The left ventricular ejection fraction was reduced from 79 +/- 6 to 72 +/- 6 per cent (p < 0.001). The initial ejection fraction diminished from 49 +/- 13 to 34 +/- 13 per cent (p < 0.01), the early diastolic filling increased from 39 +/- 11 to 52 +/- 10 per cent (p < 0.001) and the atrial contribution was reduced from 36 +/- 10 to 24 +/- 10 per cent (p < 0,001). The degree of mitral regurgitation changed from 1.4 +/- 1.2 to 0.7 +/- 0.9 (p < 0.01). CONCLUSIONS: There is an obstruction in the left ventricular outflow tract in patients with obstructive hypertrophic cardiomyopathy that is relieved with dual-chamber pacing. The reduction in the intraventricular pressure seems to improve the ventricular relaxation and the diastolic function. The decrease in the degree of mitral regurgitation and the improvement in diastolic function diminish pulmonary capillary and right circuit pressures.

Adult↗
PubMed2006

Long-period grating refractive index sensor with a modified cladding structure for large operational range and high sensitivity.

What is believed to be a novel long-period grating (LPG) refractive index sensor with a modified cladding structure is proposed and studied. In the proposed structure, the cladding of the fiber has a two-layer structure, i.e., a cladding layer of low refractive index with a reduced radius and an overlay of high refractive index. The sensitivity of the structure-modified LPG sensor to the ambient refractive index change as a function of the cladding layer and overlay parameters is investigated by way of modeling. It is found that an increase of the ambient refractive index causes a field redistribution of the cladding mode into the overlay when the parameters of the overlay are properly selected. It is shown that by reducing the radius of the cladding layer, the operational range of the LPG refractive index sensor can be as large as 0.195 (from 1.244 to 1.440) with a minimum sensitivity of 660 nm/refractive index, which represents a 31% increase of operational range in comparison with the operational range obtained from the reported structure. The design guidelines for achieving this large operation range and high sensitivity are explained by investigating the dependence of the cladding modes on the radius of the cladding layer.

Journal Article↗
PubMed1986

Validation of a simple method of assessing cardiac preejection period: a potential index of sympathetic nervous system activity.

Traditional noninvasive assessment of sympathetic nervous system (SNS) activity in cardiovascular functioning has been confounded by concurrent parasympathetic influences. Analyses of specific intervals of the cardiac cycle have indicated that the systolic preejection period (PEP) may serve as a reliable index of SNS activity independent of parasympathetic inhibition. In the present study, PEP values derived from a technique employing peripheral pulse wave tracings were compared to values obtained from simultaneous impedance cardiograph recordings. Recordings were made on 15 male subjects who were instructed to rest quietly sitting in an upright position. Results indicated that values obtained from both methods were highly correlated and not significantly different when measurement adjustments on total systole were taken into account. These findings support the validity of the fingertip peripheral-pulse method in obtaining measures of systolic time intervals under resting conditions.

Adolescent↗
PubMed2003

Change in periodic limb movement index during treatment of obstructive sleep apnea with continuous positive airway pressure.

STUDY OBJECTIVES: The following hypotheses were investigated: 1) severe obstructive sleep apnea (OSA) can mask concurrent periodic limb movement (PLM) disorder (PLMD), which becomes evident or worsens after treatment with continuous positive airway pressure (CPAP); 2) in patients with mild OSA, PLMs are not masked but may be triggered by subclinical hypopneas or respiratory effort-related arousals and improve after CPAP. DESIGN: Retrospective analysis was performed on 2 polysomnographic studies per patient--1 baseline, the second with CPAP titration. The apnea-hypopnea index (AHI) and PLM index (PLMI) under the 2 conditions were statistically analyzed. SETTING: University hospital sleep disorders center. PATIENTS: Patients were selected if they had a baseline AHI of 5 or greater and CPAP titration resulted in reduced AHI. Also, each needed to have either a PLMI of 5 or greater on baseline PSG or during CPAP titration. Patients who started or discontinued a medication that could affect PLMs after the baseline PSG were excluded. INTERVENTIONS: As clinically indicated, CPAP for OSA. MEASUREMENTS AND RESULTS: Eighty-six patients qualified and were divided into 3 groups based on OSA severity. Significant correlations (P < 0.05) were found between AHI and PLMI on the baseline PSG (-0.50), between AHI on baseline PSG and PLMI on CPAP titration (0.49), and between PLMI on baseline PSG and on CPAP titration (-0.21). The increase in PLMI during CPAP titration in patients with severe OSA was statistically significant (P < 0.001). The PLMI decreased with CPAP in 20 of 86 patients, mostly in the mild OSA subgroup. Regression of post-CPAP reduction of AHI and change in PLMI yielded a significant logarithmic relationship (R2 = 0.3042). CONCLUSIONS: Severity of OSA may determine the effect of CPAP on PLMs. The PLMs may increase in moderate to severe OSA due mainly to "unmasking" of underlying PLMD. The PLMs may decrease in mild OSA post-CPAP due to resolution of PLMs associated with respiratory effort-related arousals. This suggests that PLMs may have more than 1 etiology and may be categorized as spontaneous (as in PLMD) and induced (when secondary to respiratory effort-related arousals).

Adult↗
PubMed1997

Prophylactic transabdominal amnioinfusion in oligohydramnios for preterm premature rupture of membranes: increase of amniotic fluid index during latency period.

OBJECTIVE: This study was designed to: (i) evaluate the effect of amnioinfusion on the latency period in patients with oligohydramnios for preterm premature rupture of membranes, and (ii) to investigate the relationship between changes in the amniotic fluid index and fetal heart rate short-term variability by computerized Hewlett-Packard cardiotocography, longitudinally estimated before and after prophylactic amnioinfusion. MATERIALS AND METHODS: All singleton pregnancies with prolonged premature rupture of membranes after 25 weeks of gestation and seen at the Institute of Obstetrics and Gynecology, University of Ancona (Italy), between January 1994 and June 1995 were included in the study. Transabdominal amnioinfusion with 150-350 ml warmed normal saline (25-50 ml/min) was performed at weekly intervals. Amniotic fluid volume was assessed ultrasonographically by means of the four-quadrant technique on a weekly basis before and after each amnioinfusion, as well as the short-term variability by a Hewlett-Packard computerized cardiotocographic system. RESULTS: 18 women were enrolled and underwent prophylactic transabdominal amnioinfusion at weekly intervals until delivery. Eighteen controls, who did not undergo prophylactic amnioinfusion, were recruited from our 1992-1993 series and included in the study. The median interval between premature rupture of membranes and delivery was 3.0 weeks (range 1-8 weeks), with an average delivery age of 33.0 weeks (range 27-36 weeks). The latency period was significantly longer in patients who underwent prophylactic amnioinfusion (mean +/- SD, 4.1 +/- 1.7 weeks) than in controls(1.7 +/- 1.0 weeks; p < 0.001). An increase in both the weekly amniotic fluid index (linear regression analysis r = 0.8, p = 0.03) and the weekly short-term variability (linear regression analysis r = 0.82, p = 0.02) was observed among patients who underwent prophylactic amnioinfusion. A direct relationship was observed between the amniotic fluid index and short-term variability (linear regression analysis r = 0.54, p = 0.04). The mean values of fetal movements recorded by computerized tomography during the 20 min of observation significantly increased after amnioinfusion in comparison with those before it (2.6 +/- 0.9 and 0.9 +/- 0.7 respectively; p = 0.001). CONCLUSION: The present study has shown a positive effect of prophylactic transabdominal amnioinfusion on the latency period in patients with preterm premature rupture of membranes and oligohydramnios. Among the patients who underwent amnioinfusion, an interesting improvement in fetal heart rate short-term variability was associated with the progressive increase in amniotic fluid volume, as an expression of fetal well-being.

Abdomen↗