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PubMed1992

Determinants of Doppler indexes of left ventricular diastolic function in normal subjects (the Framingham Heart Study).

Normative Doppler values and determinants of left ventricular (LV) diastolic function in healthy subjects have not been fully elucidated. Subjects from the Framingham Heart Study were examined to describe reference values and determinants of echocardiographic Doppler indexes of diastolic function. One hundred twenty-seven randomly selected, rigorously defined, normal subjects, approximately evenly distributed by sex and age from the third through the eighth decades were studied by Doppler echocardiography. Normative values for 7 frequently used Doppler indexes of LV diastolic function are presented. Doppler indexes of LV diastolic function change dramatically with age; the peak velocity of early filling divided by late filling (peak velocity E/A) ranges from a mean of 2.08 +/- 0.55 for subjects in their third decade to 0.84 +/- 0.29 for those in their eighth decade. A peak velocity E/A ratio less than 1 is abnormal in subjects aged less than 40 years, but occurs in most subjects aged greater than or equal to 70 years. The high correlations between age and Doppler indexes of LV diastolic function are not greatly attenuated after adjustment for other clinical parameters associated with diastolic function; the multivariate partial correlation coefficient between age and peak velocity E/A is -0.80 (p less than 0.0001). Heart rate, PR interval, LV systolic function, sex and systolic blood pressure are minor determinants of Doppler indexes of diastolic function. Body mass index, left atrial diameter, and LV wall thickness, internal dimension and mass have little or no association with Doppler indexes in healthy subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

The fetal-pelvic index: a method of identifying fetal-pelvic disproportion in women attempting vaginal birth after previous cesarean delivery.

In 1986 the fetal-pelvic index was introduced as an accurate method of prospectively identifying the presence or absence of fetal-pelvic disproportion. The concept of the fetal-pelvic index is one in which the fetal head and abdominal circumferences (ultrasonographic mensuration) are compared with the respective maternal pelvic inlet and midpelvic circumferences (x-ray pelvimetry). The purpose of this study is to evaluate the efficacy of this index as a predictor of fetal-pelvic disproportion in gravid women attempting vaginal birth after previous cesarean delivery. Findings of the fetal-pelvic index are compared with those of two other means of identifying fetal-pelvic disproportion (Colcher-Sussman x-ray pelvimetry and ultrasonographically derived estimated fetal weight of greater than or equal to 4000 gm). Of the 65 prospective study participants, 18 (28%) failed to progress in labor, and a repeat cesarean delivery was required. Forty-seven of the 52 patients with a negative fetal-pelvic index value were delivered vaginally (negative predictability = 0.90). Of the five with false-negative fetal-pelvic index values, four fetuses persisted in an occipitoposterior position and failed to progress in labor. All 13 patients with a positive fetal-pelvic index value failed to progress in labor and required a cesarean delivery (positive predictability = 1.00). In contrast, when used alone, neither x-ray pelvimetry nor ultrasonography-determined estimated fetal weight of greater than or equal to 4000 gm provided accurate identification of fetal-pelvic disproportion.

Cesarean Section↗
PubMed1996

Effects of adenosine A2A receptor agonist, CGS 21680, on blood pressure, cardiac index and arterial conductance in anaesthetized rats.

The effects of 2-p-(2-carboxyethyl)phenethylamino-5'-N-ethylcarboxamidoadenosine (CGS 21680) on blood pressure, total peripheral resistance, cardiac index, heart rate and arterial conductance in different vascular beds in the presence and absence of hexamethonium (ganglionic blocker) and phenylephrine (alpha 1-adrenoceptor agonist) were investigated in pentobarbitone-anaesthetized rats using a radioactive microsphere technique. CGS 21680 (0.1, 0.3 and 1.0 microgram/kg/min) significantly decreased blood pressure and total peripheral resistance, and increased heart rate and cardiac index. In addition, after infusion with CGS 21680 (0.1, 0.3 and 1.0 microgram/kg/min) arterial conductance in coronary bed significantly increased. However, while CGS 21680 (0.3 and 1.0 microgram/kg/min) significantly increased conductance in skeletal muscle, it significantly decreased splenic arterial conductance. Moreover, CGS 21680 (1.0 microgram/kg/min) significantly increased conductance in cerebral arterial bed. Infusion with hexamethonium (200 micrograms/kg/min) resulted in significant reduction in blood pressure, heart rate and cardiac index whereas stroke volume and total peripheral resistance remained unchanged. In animals that were pretreated with hexamethonium (200 micrograms/kg/min), further administration of CGS 21680 (0.3 microgram/kg/min), compared to CGS 21680 alone, significantly reduced blood pressure, heart rate and cardiac index but did not affect total peripheral resistance or conductance in any vascular bed. Administration of phenylephrine (7 micrograms/kg/min) resulted in a significant increase in blood pressure and total peripheral resistance, and a significant reduction in cardiac index and heart rate. In animals infused with phenylephrine and CGS 21680 combined, in comparison to those animals that received CGS 21680 alone, no significant differences in blood pressure, heart rate, total peripheral resistance, cardiac index or conductance in any vascular beds were found. Our present findings suggest that CGS 21680 decreased blood pressure by decreasing total peripheral resistance, and increased cardiac index possibly through a reflex-mediated increase in heart rate. Moreover the coronary arterial bed is the most sensitive and cerebral arterial bed is the least sensitive to the effects of CGS 21680. In addition, the autonomic nervous system did not appear to play a major role in the actions of CGS 21680 on arterial conductance, and there was no difference in the action of this compound in the states of normal and raised vascular tone.

Adenosine↗
PubMed1993

Determination of the IgG index for the detection of intrathecal immunoglobulin synthesis in dogs using an ELISA.

The IgG index is a calculated quotient using IgG and albumin contents of cerebrospinal fluid (CSF) and serum to detect intrathecal IgG synthesis, which is important in the diagnosis of inflammatory infectious diseases of the central nervous system (CNS). An ELISA to measure IgG and albumin contents in blood and CSF was developed to determine the IgG index. Twenty-three normal dogs and 98 dogs with various neurological diseases were examined. In most dogs with infectious inflammatory diseases, with the exception of the acute form of nervous canine distemper, there was an elevation of the IgG index. Tumours of the CNS had an IgG index within the normal range. An elevation was found in lymphoid tumours or meningiomas with secondary cellular infiltration. Degenerative diseases, spinal cord compression and ischaemic myelopathy due to fibrocartilagenous embolism had normal or only slightly elevated IgG indices. In seven cases with inflammatory lesions there was no obvious CSF pleocytosis but the IgG index was elevated. In 17 cases in which infectious inflammatory disease was suspected, based on elevated CSF cell counts, inflammation could be excluded after determination of the IgG index. The reproducibility of the technique was found to be good and, considering the limited amount of time, expense and effort required, the determination of the IgG index in dogs is a useful extension of the conventional CSF examination.

Animals↗
PubMed1995

The ohmic perturbation duration, an original temporal index to quantify electrodermal responses.

The reactivity of the autonomic nervous system was (D.C.) recorded using six parameters simultaneously. Such a device permitted to describe a new index of skin resistance response (SRR). The ohmic perturbation duration (O.P.D. index) was defined as the period during which the subject is effectively responding to the stimulation. O.P.D. index was easily quantified because the specific part of the response, showing many fluctuations at a low resistance level, can be distinguished from the recovery part without fluctuations or with smaller microevents of different kinds. Moreover, the slope of this fluctuation is identical to that observed just before the stimulation. The comparison between the values of the O.P.D. index and classically used SRR durations enabled us to calculate the identity percentages from five other neurovegetative parameters. Results showed high values for the skin potential (91%) and skin blood flow (82.5%). These values were smaller as far as skin superficial temperature (50.5%), heart (40.8%) and respiratory (46.5%) variations were concerned. Nonetheless these last three percentages were still higher than those usually obtained with the values of the correlation coefficients from different, simultaneously recorded parameters. O.P.D. index comparison with four other classical used temporal indices (recovery time, 1/3, 1/2 and 2/3 of the recovery time) show a high significant concordance in O.P.D. index opposed to aleatory one obtained with these four other durations. Thus, the O.P.D. index could be an appropriate measure of electrodermal response (EDA) allowing any stimulus to be temporarily quantified towards sympathetic activation induced response.

Adult↗
PubMed1994

Interleukin 1 increases thymidine labeling index of normal tissues of mice but not the tumor.

PURPOSE: This study was conducted to investigate the action of human recombinant interleukin 1 as a radioprotector for different mouse normal cells other than bone marrow cells. METHODS AND MATERIALS: Semi-continuous injections of tritiated thymidine were administered every 6 h, over 24 h to determine thymidine labeling index. Mice were injected with recombinant human interleukin 1 24 h prior to tritiated thymidine and were compared to control animals that did not receive interleukin 1. Mice were killed 1 h after the last thymidine injection. The 24 h thymidine labeling index for normal tissues and RIF-1 tumor was determined. Labeling indices were also determined 1-14 days after a series of fractionated irradiations with or without pretreatment with a single dose of interleukin 1 administered 24 h prior to the first radiation. RESULTS: The thymidine labeling index of normal tissues was higher following the injection of recombinant human interleukin 1 24 h before radiolabeling. This was found in all normal tissues tested, including the lip and tongue mucosal basal cell layers, crypt cells of the duodenum, alveolar cells of the lung, hepatocytes, and basal skin cells. The thymidine labeling index of RIF-1 fibrosarcoma was not affected by interleukin 1 injection. A single interleukin 1 injection 24 h before the first radiation fraction also increased the thymidine labeling indices of normal tissues after localized fractionated irradiation. The thymidine labeling index of RIF-1 tumor was not increased by interleukin 1 administration except after relatively high radiation doses (20 Gy in five fractions). The ability of interleukin 1 to enhance the thymidine labeling index declined after the first day following the completion of fractionated irradiation. CONCLUSION: Recombinant human interleukin 1 increased the 24 h thymidine labeling index in normal tissues in mice, but not in RIF-1 tumor. Fractionated irradiation could maintain the effect of a single dose of interleukin 1, administered 24 h prior to the first fraction, up to 24 h after the end of radiation.

Animals↗
PubMed2005

Perioperative cardiovascular mortality in noncardiac surgery: validation of the Lee cardiac risk index.

PURPOSE: The Lee risk index was developed to predict major cardiac complications in noncardiac surgery. We retrospectively evaluated its ability to predict cardiovascular death in the large cohort of patients who recently underwent noncardiac surgery in our institution. METHODS: The administrative database of the Erasmus MC, Rotterdam, The Netherlands, contains information on 108 593 noncardiac surgical procedures performed from 1991 to 2000. The Lee index assigns 1 point to each of the following characteristics: high-risk surgery, ischemic heart disease, heart failure, cerebrovascular disease, renal insufficiency, and diabetes mellitus. We retrospectively used available information in our database to adapt the Lee index calculated the adapted index for each procedure, and analyzed its relation to cardiovascular death. RESULTS: A total of 1877 patients (1.7%) died perioperatively, including 543 (0.5%) classified as cardiovascular death. The cardiovascular death rates were 0.3% (255/75 352) for Lee Class 1, 0.7% (196/28 892) for Class 2, 1.7% (57/3380) for Class 3, and 3.6% (35/969) for Class 4. The corresponding odds ratios were 1 (reference), 2.0, 5.1, and 11.0, with no overlap for the 95% confidence interval of each class. The C statistic for the prediction of cardiovascular mortality using the Lee index was 0.63. If age and more detailed information regarding the type of surgery was retrospectively added, the C statistic in this exploratory analysis improved to 0.85. CONCLUSION: The adapted Lee index was predictive of cardiovascular mortality in our administrative database, but its simple classification of surgical procedures as high-risk versus not high-risk seems suboptimal. Nevertheless, if the goal is to compare outcomes across hospitals or regions using administrative data, the use of the adapted Lee index, as augmented by age and more detailed classification of type of surgery, is a promising option worthy of prospective testing.

Adult↗
PubMed2005

Use of ultrasonography to identify infants for whom urinary catheterization will be unsuccessful because of insufficient urine volume: validation of the urinary bladder index.

STUDY OBJECTIVE: Frequently, attempts to obtain catheter urine samples from infants are unsuccessful because of an empty bladder, with urinary catheterization failure rates reported up to 16%. We seek to validate a sonographic urinary bladder index that will identify patients for whom catheterization will be unsuccessful. METHODS: We conducted a prospective, blinded, observational study enrolling a convenience sample of children younger than 2 years and undergoing urinary catheterization in an urban pediatric emergency department. Failure was defined as a catheterization result of less than 2 mL of urine. Urinary bladder index, a concept we created, is defined as the product of anteroposterior and transverse diameters, expressed in centimeters squared. Sensitivity and specificity were calculated with 95% confidence intervals (CIs). RESULTS: Forty-four patients were enrolled, with a median age of 8 months (range 0.5 to 24 months) and median weight of 7.8 kg (range 1.7 to 17.7 kg). Four children urinated during the procedure and were excluded. Thirty-five had urinary bladder index greater than 2.4 cm2 (range 2.5 to 15.5 cm2 ). All were successfully catheterized. Four children had urinary bladder index less than 2.4 cm2 (range 0 to 1.2 cm 2 ). No adequate samples were obtained from those children. The bladder was not visualized at all in 1 child who was successfully catheterized. Sensitivity of the urinary bladder index to identify failure to obtain 2 mL of urine was 100% (4 of 4; 95% CI 40% to 100%), specificity was 97% (35 of 36; 95% CI 85% to 100%). CONCLUSION: A urinary bladder index less than 2.4 cm2 appears to identify infants for whom urinary catheterization will be unsuccessful because of insufficient urine volume. Ultrasonographic evaluation with urinary bladder index measurement before catheterization may eliminate the incidence of failed procedures.

Female↗
PubMed2004

Measurement of the Tei index: a comparison of M-mode and pulse Doppler methods.

BACKGROUND: The Tei index is a useful echocardiographic measure of ventricular function in adults and children. Most studies have used pulse or tissue Doppler imaging to calculate this index. M-mode, with its higher frame rate and sharp deflections, may be an accurate method of calculating the Tei index. METHODS: M-mode and pulse Doppler (PD) measurement of the Tei index were performed in 68 children. The mitral closure to opening time ("a") and ejection time ("b") intervals for calculating the Tei index were measured by M-mode and PD methods. RESULTS: Both M-mode and PD were found to be reproducible methods of calculating the Tei index. There was a close correlation between measurements of the "a" and "b" intervals by M-mode and PD, with less variability with M-mode than with PD. CONCLUSION: M-mode is a simple, reproducible echocardiographic alternative method for calculating the Tei index in children and has a lower variance than PD.

Child↗
PubMed2005

Recurrent epithelial ovarian cancer: validation and improvement of an established prognostic index.

OBJECTIVES: To validate and improve an established prognostic index in patients with recurrent ovarian cancer. METHODS: A Canadian three-covariate prognostic index (tumour grade at diagnosis, initial performance status, and time to relapse/primary progression (TRP)) was validated in a well-defined cohort of comparable Danish patients. Potential parameters to be included in an improved prognostic index were revealed by univariate and multivariate analyses in the Danish validation group. RESULTS: The Canadian index validated in the Danish patient population (n=189) found a statistical significant difference in survival between the prognostic groups good and intermediate (P<0.0001), whereas there was no significant difference in survival between the prognostic groups intermediate and poor (P=0.51). In order to improve the accuracy of the index, the candidate parameters, treatment free interval (TFI), CA125 level and performance status, at time of relapse/primary progression, were added, whereas the parameters, tumour grade, and initial performance status, from the Canadian index were excluded. As the correlation coefficient between TRP and TFI was very high (r=0.91), TRP was substituted with TFI in the improved prognostic model. The final model was: 0.8 (performance status)+0.33 log (CA125)-1.31 log (TFI). The improved model was a good predictor of one-year survival (AUC 0.85; logistic regression; P<0.0001). The median survival (with 95% CI) of the four prognostic groups (A-D) was 50.6 (34.0-not available), 25.0 (22.1-33.6), 11.3 (8.5-12.9), and 5.2 (3.5-6.3) months, respectively. CONCLUSIONS: A novel prognostic model (the Copenhagen index) for patients with recurrent ovarian cancer is presented.

Cohort Studies↗
PubMed2006

Right ventricle Tei-index: a tool to increase the accuracy of non-invasive detection of pulmonary arterial hypertension in connective tissue diseases.

OBJECTIVE: To assess the accuracy of echocardiography for predicting pulmonary arterial hypertension (PAH) in a cohort of patients with systemic sclerosis and other connective tissue diseases, and to evaluate whether addition of the right ventricular (RV) Tei-index contributes to the non-invasive diagnosis of PAH in this patient group. PATIENTS AND METHODS: Ninety-eight patients with systemic sclerosis and other connective tissue diseases in whom an echocardiography was performed in the period from January 1st 2004 to July 1st 2005 were included. Echocardiographic systolic pulmonary arterial pressure (PAP), end-diastolic PAP and RV Tei-index were calculated. In cases with a high suspicion of PAH right heart catheterization was performed and systolic, diastolic and mean PAP as well as pulmonary wedge pressure, cardiac output and pulmonary vascular resistance were obtained. These results were compared to the echocardiographic measurements. RESULTS: The average RV Tei-index of our patients was substantially above normal values. In 35 (36%) patients a right heart catheterization was performed and PAH was confirmed in 28 patients. In 6 of 7 patients without PAH, the RV Tei-index was below the upper limit of normal. A significant correlation was found between the RV Tei-index and the catheterization parameters such as systolic PAP, diastolic PAP and mean PAP. CONCLUSION: The accuracy of echocardiography for the detection of PAH increases when the echocardiographic systolic PAP is combined with an elevated RV Tei-index. As a result, by applying the Tei-index, the number of negative catheterizations can be minimized.

Cardiac Catheterization↗
PubMed2005

Combined use of brachial-ankle pulse wave velocity and ankle-brachial index for fast assessment of arteriosclerosis and atherosclerosis in a community.

BACKGROUND: Pulse volume recordings and blood pressures at arms and ankles can be obtained automatically and simultaneously to allow fast measurements of the brachial-ankle pulse wave velocity and the ankle-brachial index. We applied this novel technique to assess the extent of arteriosclerosis and atherosclerosis in a community. METHODS: A total of 1329 residents in Kinmen completed a health survey including interview, physical examination, blood test, and the measurements of brachial-ankle pulse wave velocity and ankle-brachial index in 10 working days. RESULTS: Brachial-ankle pulse wave velocity was significantly related to age, systolic blood pressure, body mass index, waist circumference, ankle-brachial index, and fasting blood levels of glucose, triglyceride, high-density lipoprotein cholesterol, uric acid, and creatinine, and was significantly related to the 10-year risk of developing coronary heart disease estimated from the Framingham risk function. The prevalence of arteriosclerosis as defined by brachial-ankle pulse wave velocity values higher than the age and sex stratified references from the low risk subjects was 27.1% for men and 25.4% for women. The prevalence of atherosclerosis defined by ankle-brachial index <0.9 was 2.8% in men and 1.7% in women. In men but not in women, subjects with low ankle-brachial index had significantly greater risk for developing coronary artery disease than those with normal values. CONCLUSIONS: Brachial-ankle pulse wave velocity and ankle-brachial index can be obtained simultaneously and quickly for the assessment of arteriosclerosis and atherosclerosis in a community.

Adult↗
PubMed2004

An adaptation of Charlson comorbidity index predicted subsequent mortality in a health survey.

OBJECTIVE: The Catalan Health Interview Survey Follow-up Study analyzed survival differences according to comorbidity, using an adaptation of the Charlson's index. STUDY DESIGN AND SETTING: Vital status was ascertained by record linkage with death certificates 5 years after interview. Three thousand one hundred five men and 3,536 women aged 40-84 years old were included in the analysis. Proportional hazards models with age as time scale were used to calculate relative risk (RR) and 95% confidence interval adjusted for potential confounders. RESULTS: The adjusted RR of death in men was 1.02 (0.73-1.41) for a comorbidity index of 1-2; the RR was 1.51 (1-2.30) for an index of 3-4, and 2.64 (1.43-4.89) for an index of >4 composed to an index of 0. In women, for the same comorbidity index categorization, the RR of death were 0.83 (0.55-1.24), 1.71 (1.09-2.72) and 2.65 (1.47-4.77). CONCLUSION: This result confirms the relation between comorbidity and the risk of death based on a comorbidity index that takes into account severity and number of self-declared chronic diseases with mortality.

Adult↗
PubMed2005

Large-scale effects on resistivity index of porous media.

The estimation of humidity in the unsaturated zone of soils and NAPL saturation in contaminated aquifers may be based on the interpretation of electrical resistivity index logs. In the present work, concepts of the theory of the two-phase flow in pore networks are employed to interpret the form of the equilibrium and dynamic resistivity index curves of large porous samples. A resistivity cell is constructed to measure the capillary and electrical properties of large samples of unconsolidated porous media. The drainage capillary pressure and resistivity index curves of a sand column are measured by using the micropore membrane (porous plate) method, where a 0.5% wt/vol NaCl aqueous solution is displaced by n-dodecane. The dynamic resistivity index curves are measured by using the continuous injection technique for various orientations of the sand column. Based on concepts of the two-phase flow theory, concerning the dominant displacement growth pattern in a pore network and arising from the cooperative effects of capillary, buoyancy, and viscous forces, approximate relationships are developed for the resistivity index and saturation exponent as functions of the water saturation. The saturation exponent decreases as the displacement advances and the fluid distribution across the sand column tends to be homogenized after oil breakthrough. Both the resistivity index and saturation exponent increase as the displacement pattern tends to become compact and stable. In the destabilized flow pattern, as the Bond number decreases, the resistivity index may increase respectably within a narrow range of values of the Bond number. This happens when the thickness of the unstable capillary finger exceeds the lateral dimension of the porous sample and becomes a fractal percolation cluster. The saturation exponent becomes almost constant and independent of water saturation only over the destabilized displacement pattern at high values of the Bond number.

Alkanes↗
PubMed2006

The Hardman index in patients operated on for ruptured abdominal aortic aneurysm: A systematic review.

BACKGROUND: The aims of the present study were to (1) analyze preoperative predictors for outcome suggested by Hardman and surgical mortality after open repair and endovascular repair (EVAR) of ruptured abdominal aortic aneurysms (rAAA), and (2) further evaluate the Hardman index in a systematic review. METHODS: Patients operated on for rAAA during a 5-year period between 2000 and 2004 were scored according to Hardman-1 point for either age >76 years, loss of consciousness after presentation, hemoglobin <90 g/L, serum creatinine >190 micromol/L or electrocardiographic (ECG) signs of ischemia-with blinded evaluation of ECGs by a specialist in clinical physiology. The results were included in a systematic review of studies evaluating the Hardman index. RESULTS: In-hospital mortality after operation was 41% (67/162). There was no difference in in-hospital mortality between open repair (n = 106) and EVAR (n = 56), whereas the Hardman index was associated with operative mortality in our institution and in the systematic review of 970 patients (P < .001). Mortality rate in patients with Hardman index > or =3 was 77% in the pooled analysis. A full data set of all five scoring variables was obtained in 94 (58%) of 162 patients in our study, and potential underscoring was thus possible in 68 patients. Of the available ECGs, 12 (8.7%) of 138 were judged nondiagnostic. Five studies did not state their missing data on ECG and hemoglobin and serum creatinine concentrations, nor did they specify the criteria for ECG ischemia. CONCLUSIONS: A strong correlation between the Hardman index and mortality was found. A Hardman index > or =3 cannot be used as an absolute limit for denial of surgery. The utility of the Hardman index seems to be impeded by variability in scoring resulting from missing or nondiagnostic data.

Aneurysm, Ruptured↗
PubMed2006

A combined bootstrap/histogram analysis approach for computing a lateralization index from neuroimaging data.

Cerebral hemispheric specialization has traditionally been described using a lateralization index (LI). Such an index, however, shows a very severe threshold dependency and is prone to be influenced by statistical outliers. Reliability of this index thus has been inherently weak, and the assessment of this reliability is as yet not possible as methods to detect such outliers are not available. Here, we propose a new approach to calculating a lateralization index on functional magnetic resonance imaging data by combining a bootstrap procedure with a histogram analysis approach. Synthetic and real functional magnetic resonance imaging data was used to assess performance of our approach. Using a bootstrap algorithm, 10,000 indices are iteratively calculated at different thresholds, yielding a robust mean, maximum and minimum LI and thus allowing to attach a confidence interval to a given index. Taking thresholds into account, an overall weighted bootstrapped lateralization index is calculated. Additional histogram analyses of these bootstrapped values allow to judge reliability and the influence of outliers within the data. We conclude that the proposed methods yield a robust and specific lateralization index, sensitively detect outliers and allow to assess the underlying data quality.

Brain↗
PubMed1996

Day-to-day variation in iron status indexes is similar for most measures in elderly women with and without rheumatoid arthritis.

OBJECTIVE: To determine the day-to-day variation in biochemical measures of iron status in a group of elderly women with rheumatoid arthritis compared with a group of healthy elderly women. DESIGN: Venous blood samples were collected from each subject on 3 nonconsecutive days during a 2-week study period; subjects had fasted overnight. Variability in hemoglobin level, hematocrit value, serum iron concentration, total iron-binding capacity, transferrin saturation, serum ferritin concentration, and plasma transferrin receptor level was determined. SUBJECTS: Two groups of women, one with rheumatoid arthritis (n=10) and another that was apparently healthy (n=10). STATISTICAL ANALYSES: Variance component analysis was used to estimate the biological variation (sigma square day) and analytic variation (sigma square rep) for each iron index. The coefficient of variation (CV) for each variance component was calculated: coefficient of biological variation = CV day, coefficient of analytic variation = CV rep, and coefficient of a single future determination = CV fd. RESULTS: The CV rep for all iron indexes was smaller than the CV day in both groups. The CV day was considerably higher for serum iron concentration and for transferrin saturation than for the other indexes in both groups (16.6% and 16.6% in healthy subjects and 33.6% and 28.2%, respectively, in subjects with rheumatoid arthritis). The higher CV day for serum iron concentration and transferrin saturation translated into a higher CV fd for these indexes. Because of the higher variance for these two indexes, more sampling days were required for reliable estimates. CV day and CV fd for plasma transferrin receptor level were relatively low. CONCLUSIONS: These findings corroborate our previous finding that variation of serum ferritin concentration in the elderly is lower than that demonstrated in younger populations. This aging effect persists in the presence of rheumatoid arthritis. Fasting appeared to improve reliability in the determinations for serum iron concentration and transferrin saturation. Variability estimates for the indexes other than serum iron concentration and transferrin saturation were not altered by the inflammation of rheumatoid arthritis. Plasma transferrin receptor level is a reliable index for assessing iron status in populations with rheumatoid arthritis.

Aged↗
PubMed1998

Value of a Doppler-derived index combining systolic and diastolic time intervals in predicting outcome in primary pulmonary hypertension.

Primary pulmonary hypertension is characterized by elevated pulmonary arterial pressure and vascular resistance, frequently producing right heart failure and death. Therefore, the Doppler right ventricular (RV) index, which is a measure of global RV function, could be a useful predictor of outcome in primary pulmonary hypertension. The Doppler RV index, defined as the sum of isovolumic contraction time and isovolumic relaxation time divided by ejection time, was retrospectively measured in 53 patients (38 women, aged 45 +/- 14 years) with primary pulmonary hypertension. Ejection time was measured from the pulmonary outflow velocity signal. The sum of isovolumic contraction time and isovolumic relaxation time was obtained by subtracting ejection time from the duration of tricuspid regurgitation. The Doppler RV index tended to be elevated (median 0.83) compared with normal ranges. Normal Doppler RV index was 0.28 +/- 0.04. After a mean follow-up duration of 2.9 years, 4 patients underwent lung transplantation and 30 patients died; the cause was cardiac in 28, noncardiac in 1, and uncertain in 1. Univariately, the Doppler RV index (chi-square 20.7, p <0.0001), severity of tricuspid regurgitation (chi-square 8.2, p = 0.004), treatment with calcium blockers (chi-square 6.6, p = 0.01), heart rate (chi-square 5.1, p = 0.02), and symptom status (chi-square 4.9, p = 0.03) were associated with adverse outcome (cardiac deaths and lung transplantation). However, only the Doppler RV index and treatment with calcium blockers were independent predictors within the multivariate model. Our results indicate that the Doppler RV index is a useful predictor of adverse outcome in patients with primary pulmonary hypertension.

Adult↗