Israel Medical Association Journal

Background: Upper respiratory tract illnesses have been associated with an increased risk of morbidity and mortality.

Objective: To assess the influence of vaccination against influenza on the risk of hospitalization in internal medicine and geriatric wards, and the risk of death from all causes during the 2000–2001 influenza season.

Methods: A historical cohort study was conducted using computerized general practitioner records on patients aged 65 years and above, members of “Maccabi Health Care Services” – the second largest health maintenance organization in Israel with 1.6 million members. The patients were divided into high and low risk groups corresponding to coexisting conditions, and were studied. Administrative and clinical data were used to evaluate outcomes.

Results: Of the 84,613 subjects in the cohort 42.8% were immunized. At baseline, vaccinated subjects were sicker and had higher rates of coexisting conditions than unvaccinated subjects. Vaccination against influenza was associated with a 30% reduction in hospitalization rates and 70% in mortality rates in the high risk group. The NNT (number needed to treat) measured to prevent one hospitalization was 53.2 (28.2 in the high risk group and 100.4 in the low risk group). When referring to length of hospitalization, one vaccine was needed to prevent 1 day of hospitalization among the high risk group. Analyses according to age and the presence or absence of major medical conditions at baseline revealed similar findings across all subgroups.

Conclusions: In the elderly, vaccination against influenza is associated with a reduction in both the total risk of hospitalization and in the risk of death from all causes during the influenza season. These findings compel the rationale to increase compliance with recommendations for annual influenza vaccination among the elderly.

Background: Multifetal pregnancy reduction has been implemented for improving the outcome of multifetal pregnancies. Recent studies reported no difference in pregnancy outcome between reduced twins and non-reduced twins, but the neonatal course and subsequent outcome in reduced twin pregnancies were not well documented.

Objective: To compare the neonatal course and outcome, as well as the gestational and labor characteristics, in twins from reduced multifetal pregnancies and in non-reduced twins.

Methods: This is a retrospective case-control study of the neonatal course of twins from reduced multifetal pregnancies. We found 64 mothers with multifetal pregnancy reduction who delivered twins during 1989–1997; 64 gestational age-matched non-reduced twin pregnancies served as controls. The following neonatal variables were examined: major malformations; small birth weight for gestational age; and neonatal morbidities including respiratory distress syndrome, apnea, pneumothorax, bronchopulmonary dysplasia, hyperbilirubinemia, sepsis, necrotizing enterocolitis, retinopathy of prematurity, seizures, intraventricular hemorrhage, periventricular leukomalacia, ventriculomegaly, and hydrocephalus. In addition, we evaluated several neonatal interventions (surfactant replacement, mechanical ventilation, phototherapy, total parenteral nutrition), and some laboratory abnormalities (thrombocytopenia, leukopenia, anemia, and hypoglycemia), duration of hospitalization, and neonatal mortality.

Results: Gestational and labor variables were not significantly different between multifetal pregnancies reduced to twins and non-reduced twin pregnancies. The neonatal morbidity and mortality were not significantly different between twin neonates from multifetal pregnancy reduction and non-reduced control twins.

Conclusions: Multifetal pregnancy reduction to twins appears to bear no adverse effect on the intrauterine course of the remaining fetuses or their neonatal course and outcome when born after 28 weeks of gestation.
 

Background: Multiple factors are involved in the pathogenesis of hypertension in the obese individual.

Objective: To evaluate the role of a decrease in sympathetically mediated thermogenesis and the effect of the correlation between the plasma leptin and daily urinary nitric oxide levels on obesity-related hypertension.

Methods: We evaluated three groups: 25 obese hypertensive patients (age 45.7±1.37 years, body mass index 34.2±1.35 kg/m², systolic/diastolic blood pressure 155±2.9/105±1.3, mean arterial pressure 122±1.50 mmHg); 21 obese normotensive patients (age 39.6±1.72, BMI[1] 31.3±0.76, SBP/DBP[2] 124±2.1/85.4±1.8, MAP[3] 98.2±1.80); and 17 lean normotensive subjects (age 38.1±2.16, BMI 22.1±0.28, SBP/DBP 117±1.7/76.8±1.5, MAP 90.1±1.50). We determined basal resting metabolic rates, plasma insulin (radioimmunoassay), norepinephrine (high performance liquid chromatography) in all subjects. Thereafter, 14 obese hypertensives underwent a weight reduction diet. At weeks 6 (n=14) and 14 (n=10) of the diet the above determinations were repeated. Plasma leptin (enzyme-linked immunosorbent assay) and UNOx[4] (spectrophotometry) were assayed in 17 obese hypertensives and 17 obese normotensives, and in 19 obese hypertensives versus 11 obese normotensives, respectively.

Results: Obese hypertensive patients had significantly higher basal RMR[5] and plasma NE[6] levels. Insulin levels were lower in the lean group, with no difference between the hypertensive and normotensive obese groups. At weeks 6 and 14, BMI was significantly lower, as were insulin and NE levels. RMR decreased to values of normotensive subjects. MAP normalized but remained significantly higher than that of obese normotensives. Leptin blood levels and the leptin/UNOx ratio were significantly higher in the obese hypertensive compared to the obese normotensive patients. Both these parameters were strongly correlated to BMI, MAP⁵, RMR, and plasma NE and insulin .Obese hypertensive patients excreted less urinary NO metabolites. A strong correlation was found between MAP and the leptin/UNOx ratio.  

Conclusions: A reduction of sympathetically mediated thermogenesis, as reflected by RMR, results in normalization of obesity-related hypertension. In contrast, insulin does not seem to play a major role in the pathogenesis of hypertension associated with obesity. Increased leptin levels in conjunction with decreased NO production in the presence of enhanced sympathetic activity may contribute to blood pressure elevation in the obese.

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[1] BMI = body mass index

[2] SBP/DBP = systolic blood pressure/diastolic blood pressure

[3] MAP = mean arterial pressure

[4] UNOx = urinary nitric oxide

[5] RMR – resting metabolic rate

[6] NE = norepinephrine

Background: Percutaneous transluminal septal ablation was recently introduced as an alternative to surgical treatment of hypertrophic obstructive cardiomyopathy. In this procedure, alcohol is injected into a proximal septal artery to create a localized myocardial infarction.

Objectives: To characterize the immediate and mediumterm results following PTSMA.

Methods: Of 13 patients referred for PTSMA, 8 were found suitable for the procedure. Hemodynamic parameters were evaluated prior to and following the procedure, and clinical and echo-Doppler parameters at 2 weeks and 9 months later.

Results: The procedure was technically successful in all patients. Resting left ventricular outflow gradient at rest (by Doppler) fell from 82 + 37 to 15 + 8 mmHg (P<0.001) 9 months later. Late post-procedural gradient after the Valsalva maneuver was 2 + 24 mmHg. The degree of mitral regurgitation fell from 2.0 + 0 to 1.5 + 0.5 (P<0.05). New York Heart Association class for dyspnea improved from 2.8 + 0.5 to 1.8 + (P<0.01) and Canadian Cardiovascular Society class for angina from 2.0 + 1.3 to 1.3 + 1.2 (P=0.08). Complete right bundle branch block developed in six patients, temporary complete atrioventricular block in three, and persistent block requiring permanent pacing in one. No flow in the distal left anterior descending coronary artery (presumably due to spilling of alcohol) was seen in one (with development of a small antero-apical infraction) and ventricular fibrillation 2 hours post-procedure in one. None of the patients died.

Conclusion: PTSMA provided a substantial reduction in left ventricular outflow gradient associated with an improvement in symptomatology. Serious complications are not uncommon. Long-term follow-up is unknown.