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PubMed1982

The relationship of body fat weight, determined densitometrically, to relative weight and triceps skinfold in American youths, 12-17 years of age.

The relationship between fat weight, measured densitometrically, and the triceps skinfold and Quetelet's Index has been analyzed by means of linear regression analysis of 235 American youths, 12-17 years of age; 48 males and 41 females were from Minneapolis and 121 males and 25 females from the Greater Philadelphia area. Validation was accomplished by using the results of 10 separate regression analysis, each on 90% of the sample, the remaining 10% serving in each instance as the validation group; this is known as the Jackknife Method. When the Minneapolis and Philadelphia components were pooled, suitable regression models were derived with standard deviations of the errors of prediction of 3.330 kg in males and 2.056 in females. When the sample was subdivided by city the SD's remained essentially the same, but the mean errors were larger. It is concluded that the linear regression models can be used on closely similar populations to estimate fat weight for groups, but estimates for individuals may be expected to have an error of +/- 5-6 kg (i.e., 2 SD's) and are therefore not likely to be suitably accurate for use. The regression weights indicate a greater contribution of the triceps skinfold to fat weight than of Quetelet's Index in males. In females the reverse was found. This may affect sex differences in prevalence rates of obesity, if the diagnosis is based upon a single anthropometric indicator.

Adipose Tissue↗

PubMed1991

Reasons for the lack of benefit of immediate angioplasty during recombinant tissue plasminogen activator therapy for acute myocardial infarction: a regional wall motion analysis. European Cooperative Study Group.

Regional ventricular wall motion analysis utilizing three different methods was performed on predischarge left ventriculograms from 291 of 367 patients enrolled in a randomized trial of single chain recombinant tissue-type plasminogen activator (rt-PA), aspirin and heparin with and without immediate angioplasty in patients with acute myocardial infarction. With univariate analysis, no difference in regional wall motion variables between the two treatment groups was observed. However, with individual baseline risk assessment by multivariate linear regression analysis using baseline characteristics known to be related to left ventricular function after thrombolytic therapy or outcome of coronary angioplasty, or both, an excess of high risk patients in the invasive treatment group was detected. To adjust for this unequal distribution of baseline risk, multivariate linear regression analysis was performed. No benefit of immediate coronary angioplasty was observed after adjustment. Reocclusion or reinfarction, or both, occurred more frequently in the invasive than in the noninvasive treatment group (18% versus 13%, respectively). Among patients with a patent infarct-related vessel on angiography between days 10 and 22 and without reinfarction before angiography, there was a trend toward benefit from the invasive strategy, indicating that reocclusion and reinfarction might be responsible for the lack of benefit of the invasive strategy. This implies that immediate coronary angioplasty may be beneficial in selected patients, provided that these complications can be prevented.

Angioplasty, Balloon, Coronary↗

PubMed2000

Beat-to-beat measurement of cardiac output by intravascular pulse contour analysis: a prospective criterion standard study in patients after cardiac surgery.

OBJECTIVE: To evaluate the accuracy of a new pulse contour method of measuring cardiac output in critically ill patients. DESIGN: A prospective criterion standard study. SETTING: Cardiac surgery intensive care unit in a university hospital. PARTICIPANTS: Nineteen cardiac surgery patients requiring intensive care treatment with pulmonary artery catheters after surgery. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The pulse contour cardiac output monitor uses transpulmonary bolus thermodilution measurements to calibrate the system. In each patient, the pulse contour cardiac output values were compared with conventional thermodilution. The method described by Bland and Altman and linear regression analysis were used for comparison. The mean difference (bias) +/- standard deviation of differences (precision) was 0.31 +/- 1.25 L/min for pulmonary bolus thermodilution cardiac output versus pulse contour cardiac output and 0.21 +/- 0.73 L/min for pulmonary bolus thermodilution cardiac output versus transpulmonary bolus thermodilution cardiac output. Linear regression (correlation) analyses were pulse contour cardiac output = 0.97 thermodilution + 0.53 (r = 0.88), and transpulmonary cardiac output = 0.87 thermodilution + 1.09 (r = 0.96). There was a small increase 60 minutes after recalibration but not a statistically significant difference between pulse contour cardiac output and pulmonary bolus thermodilution cardiac output (p = 0.52). CONCLUSIONS: Bias and precision are acceptable, and the system provides results that agree with conventional thermodilution. This study demonstrates the clinical applicability of the pulse contour cardiac output monitoring system.

Adult↗

PubMedDate not supplied

Hemoglobin Glycosylation Index is not related with blood glucose.

OBJECTIVE: Accurate assessment of blood glucose control is essential to prevent chronic complications in diabetes. Hemoglobin Glycosylation Index (HGI) quantifies the degree to which individuals demonstrate a HbA(1C) higher or lower than average for the population. This study has aimed to assess the relationship between HGI and blood glucose. METHODS: 25 type 1 diabetes subjects (12 men and 13 women), 22.0+/-5.2 (17-34) years old, were instructed to self-monitor glucose with the One Touch Profile capillary glucose meter. HbA(1C) was determined and self-monitored blood glucose levels were studied every 3 months. Diabetic patients were monitored for 3-9 months and 62 measurements of HbA(1C) were included. HbA(1C) was measured by HPLC. Mean blood glucose (MBG) was calculated from self-monitored blood glucose records. A linear regression was calculated between HbA(1C) and MBG during the 60 days before sampling to determine HbA(1C). For each diabetic patient's MBG, a predicted HbA(1C) was calculated from the population regression equation. HGI was then calculated as HGI=observed HbA(1C)-predicted HbA(1C). Blood glucose was analyzed within target range (WTR), below target range (BTR) and above target range (ATR) according to The European Diabetes Policy Group Consensus for type 1 diabetes. RESULTS: A good linear regression between HbA(1C) and MBG was observed (r=.71, r(2)=.497, P=.000). No correlation was found between HGI and the percentage of WTR, BTR or ATR values. Moreover, the percentage of self-monitored blood glucose ATR and BTR was the same for high glycosylators (HGI<0 and ATR: 56.2+/-20.9%; HGI<0 and BTR: 34.5+/-17.5%) as for low glycosylators (HGI>0 and ATR: 52.8+/-25.5%; HGI>0 and BTR: 25.1+/-15.0%). CONCLUSIONS: HGI is determined for both physiological factors and blood glucose. A prospective study is necessary to assess whether HGI, together with HbA(1C), can predict the incidence and severity of chronic complications in diabetic patients.

Adolescent↗

PubMed2003

Effects of ACE I/D and AT1R-A1166C polymorphisms on blood pressure in a healthy normotensive primary care population: first results of the Hippocates study.

BACKGROUND: Several studies have assessed the relationship between the angiotensin-converting enzyme (ACE) I/D or angiotensin II type 1 receptor (AT(1)R)-A C polymorphisms and blood pressure (BP). Since most data have been obtained in selected populations, the present study was performed in a healthy normotensive primary care population. OBJECTIVE: To investigate the individual effects of the aforementioned polymorphisms and their interaction on BP. METHODS: This cross-sectional study included 198 healthy subjects. Office BP was measured and polymorphisms were genotyped (polymerase chain reaction). Polymorphism interaction was tested using the following model: systolic blood pressure (SBP) (or diastolic blood pressure, DBP) = b(0)+ b(1)X + b(2)Y + b(3)XY, in which X and Y represent the polymorphisms' risk alleles. RESULTS: The ACE I/D polymorphism was associated with SBP (P = 0.002) and DBP (P = 0.004); highest pressures tracked with the DD genotype. Furthermore, in multiple linear regression analysis the ACE D allele was associated with SBP (P = 0.005) and DBP (P = 0.001), when adjusted for body mass index (BMI) and age. With respect to the AT(1)R-A C polymorphism, SBP was highest in the CC genotype (P = 0.025). In linear regression analysis the C allele was not associated with SBP. No synergistic effect of ACE D and AT(1)R C alleles on BP was found. Nevertheless, highest DBP tracked with the DDCC combination in comparison with other homozygous allele combinations (P = 0.030). CONCLUSIONS: This study confirmed an association of ACE I/D and AT(1)R-A C polymorphisms with BP in a healthy normotensive primary care population. Although synergistic effect of both polymorphisms on BP does not seem to be present, an additive effect on DBP is likely.

Adenine↗

PubMed1991

Comparison of computerized and examiner-administered neurobehavioral testing techniques.

To better understand the relationship of newly developed computerized neurobehavioral tests to their examiner-administered counterparts, performance on four pairs of tests was compared among 185 solvent-exposed workers in the paint manufacturing industry. Two approaches to the comparison of the test methods (computer or examiner) were employed: (1) the multitrait-multimethod correlation matrix and (2) linear regression modeling of the difference scores between pairs of tests (same functional domain, different test formats). The data revealed that the validity criteria of the multitrait-multimethod technique were met for the tests of simple visual reaction time and attention-concentration (digit symbol substitution). Linear regression analyses demonstrated that the digit symbol substitution and visual memory test pairs were differentially affected by age, vocabulary, solvent exposure, or manual dexterity. Overall, this latter approach holds promise as a means of understanding test format similarities and differences.

Adult↗

PubMed1999

Clinical and financial impact of intravenous erythromycin therapy in hospitalized patients.

OBJECTIVE: To determine the economic consequences of intravenous erythromycin use in hospital patients in a variety of clinical circumstances. DESIGN: Retrospective cohort study of patients with specified primary diagnosis-related group discharge diagnoses treated from January 1, 1990, to December 31, 1994, who received erythromycin, and a matched cohort group from the same period who did not receive erythromycin. SETTING: LDS Hospital, Salt Lake City, UT, a 520-bed teaching hospital. PATIENTS: A long-term archive of clinical and financial data from a computerized hospital information system was searched for patients meeting a strict case definition. This archive contained information on erythromycin exposure as well as concurrent drug therapy and adverse drug events that had been prospectively evaluated during hospitalization throughout the study and cohort periods. Detailed costs were available for each patient. MAIN OUTCOME MEASURE: Attributable differences in lengths of stay and total costs determined using linear regression modeling. RESULTS: For 797 erythromycin patients and 2771 cohort patients, we found an attributable increased length of stay of 2.14 days and an increased cost of hospitalization of $6061 for erythromycin case patients. Case patients also had a significantly increased risk of adverse drug events. Linear regression modeling showed that erythromycin use was significantly related to increased length of stay and cost of hospitalization. CONCLUSIONS: Intravenous erythromycin use has been associated with significant increases in hospital length of stay and total hospital cost.

Adolescent↗

PubMedDate not supplied

[Factors related to frequency of sexual activity of postmenopausal women].

OBJECTIVE: To identify factors related to the frequency of sexual activity of postmenopausal women METHODS: A cross-section study of 206 postmenopausal women between 45 and 60 years of age was made at a university health care service in the South of Brazil between June and October 2002. Evaluations were made of sexual activity according to the number of sexual intercourses in the previous month and the climacteric symptoms using the Kupperman index. Statistical analysis was performed with multiple linear regression analysis. RESULTS: Of those surveyed 176 (85%) women were sexually active. Although 60.6% reported a decrease in sexual activity after menopause, mostly attributing it to the husband's sexual impotence (41.7%). Approximately 25.7% stated they had no satisfaction with sexual intercourse. By means of multiple linear regression analysis the following aspects were associated to sexual activity: age (p<0.1), degree of sexual satisfaction (p=0.01), and climacteric symptomatology (p=0.02). As age increased the climacteric symptoms were more intense and sexual activity was less frequent with lower sexual satisfaction. The climacteric symptoms correlated with sexual activity were: hot flashes (p=0.05), irritability (p=0.04), melancholy/sadness (p=0.04), arthralgia/myalgia (p<0.01) and weakness/tiredness (p<0.01). CONCLUSION: Findings of this study were similar to those in literature. They agree with the hypothesis that sexuality of climacteric women is not only influenced by factors related to hypoestrogenism, but also by psychosocial and cultural aspects associated with aging itself. Nevertheless, longitudinal studies are necessary to provide more conclusive data. Special attention should be given to the sexual dysfunction of men.

Body Mass Index↗

PubMed2002

Deceleration energy and change in velocity on impact: key factors in fatal versus potentially survivable motor vehicle crash (mvc) aortic injuries (AI): the role of associated injuries as determinants of outcome.

OBJECTIVE: To examine the difference in force mechanisms between fatal and potentially survivable MVC aortic injuries (AI) compared to non-AI severe thoracic injuries (ST). METHODS: Of 324 autopsied MVC driver or front seat passenger fatalities (1997-2000), there were 43 fatal AI (36 scene deaths, 7 hospital deaths) and 5 additional AI survivors. RESULTS: Of the 48 AI, there was only a 42% survival for those reaching hospital alive. 80% of AI survivors had isthmus lesions and all had no or minimal brain injury (GCS >= 13), no cardiac injury and only 20% ribs 1-4 fx or shock; of AI non-survivors reaching hospital alive, 67% had GCS <= 12, 50% cardiac injury, 83% ribs 1-4 fx and 83% shock; AI scene deaths had 78% severe brain injury, 56% cardiac injury, 69% lung injury and 78% ribs 1-4 fx. Quantifying forces in AI scene mortality: the Instantaneous Velocity on Impact of the subject vehicle (delta V1) and the Impact Energy Dissipated (IE) on the subject vehicle (V1) in joules demonstrated a linear regression in fatal car MVC AIs: Energy dissipated (joules) = -56.65 x (delta V1)(2) + 15972 x delta V1 - 454661, r(2) = 0.83. However, for 27 patients with non-AI but severe thoracic (ST) injury (AIS>=3), the relationship of IE to delta V1 had a linear regression of Energy dissipated (joules) = -5.0787 x (delta V1)(2) + 4282.1 x delta V1 - 57182 1, r(2) = 0.84, with the slope difference between the regression for AI scene deaths and that of ST and AI survivors being significant (p<0.05). Based on these relationships, a Critical Zone limited by MVC Impact Energy level of 336000 joules and a delta V1 of 64 kph appears to be the limit of potential survivability in MVCs producing aortic injuries. All AI above these thresholds died. In contrast, ST had greater use of seatbelts (AI 10% vs all ST 60%) and airbags (AI 50% vs all ST 72%), and an 83% survival. CONCLUSION: The data suggest different mechanisms of force delivery and injury patterns in fatal vs potentially survivable AI, and vs ST MVCs. They suggest that an approach to improving vehicle safety measures for AI may involve better safety devices and mechanisms for reducing that fraction of Impact Energy dissipated on V1 for a given delta V1 which is focused on the upper portion of the subject's thoracic cage between the levels of ribs1-8.

Acceleration↗

PubMed1997

Correlation between the visual field indices and Heidelberg retina tomograph parameters.

PURPOSE: We wished to determine whether a relationship exists between Heidelberg retina tomograph (HRT) parameters and the visual field indices. METHODS: One eye was randomly chosen from 59 normal patients [normal visual field and normal optic nerve head (ONH) and intraocular pressure (IOP) < 21 mm Hg], 64 ocular hypertensive patients (normal visual field and normal OHN and IOP > 22 mm Hg), 124 high-tension glaucoma patients (abnormal visual field and/or abnormal optic nerve and IOP > 22 mm Hg) and 47 low-tension glaucoma patients (abnormal visual field and or optic disc and IOP < 21 mm Hg). All the patients were examined with Humphrey Perimeter, program 30-2, and HRT. Findings were assessed by analysis of variance, Pearson's correlation coefficient, and multiple linear regression. RESULTS: Among all subjects, we noted a statistically significant correlation (Pearson's r, p < 0.001) between cup area, cup/disc area ratio, rim area, rim volume, cup shape measure, and retinal nerve fiber layer cross-section area with mean deviation and corrected pattern SD. Multiple linear regression analysis demonstrated that rim area was the most important predictor of mean deviation and corrected pattern SD. CONCLUSIONS: The presence of significant correlations between some HRT parameters, such as rim area and cup shape measure and visual field indices, suggests that these HRT parameters could be good indicators of the degree of glaucomatous ONH damage.

Glaucoma, Open-Angle↗

PubMedDate not supplied

Age- and height-specific reference limits of blood pressure of Indian children.

BACKGROUND: Blood pressure in childhood is the most powerful predictor of hypertension in adults. Norms for blood pressure in children are based on the age- and height-specific distribution of blood pressure in a reference sample of healthy children. METHODS: We performed a cross-sectional survey of school-children in the age group 5 to 14 years in south Delhi and studied the distribution of systolic and diastolic blood pressure in 8293 children (4623 boys and 3670 girls). Blood pressure was measured in all children with a mercury column sphygmomanometer using a standardized technique. The first and the fourth Korotkoff sounds were taken as indicative of the systolic and the diastolic blood pressure, respectively. Height percentiles were computed for the study sample for every one-year sex-pooled group. Multiple linear regression was then performed for every one-year group in order to estimate the 90th and 95th percentiles of systolic and diastolic blood pressure according to percentiles of height. RESULTS: Age and height, but not gender, emerged as the principal determinants of systolic and diastolic blood pressure in multivariable linear regression analyses. Age- and height-specific 90th and 95th percentile values of systolic and diastolic blood pressure were estimated, which enabled us to categorize children into 'normal', 'high normal' and 'high' blood pressure groups. CONCLUSIONS: We present age- and height-specific reference values for blood pressure of Indian children based on a large study sample. The use of these standards should aid the identification of children with high blood pressure.

Adolescent↗

PubMed2006

Specific factors for prenatal lead exposure in the border area of China.

The objectives of this study are to examine the prevalence of increased blood lead concentrations in mothers and their umbilical cords, and to identify risk factors for prenatal lead exposure in Kunming city, Yunnan province, China. The study was conducted at two obstetrics departments, and 100 peripartum women were enrolled. The mean blood lead concentrations of the mothers and the umbilical cords were 67.3microg/l and 53.1microg/l, respectively. In multiple linear regression analysis, maternal occupational exposure, maternal consumption of homemade dehydrated vegetables and maternal habitation period in Kunming city were significantly associated with an increase of umbilical cord blood lead concentration. In addition, logistic regression analysis was used to assess the association of umbilical cord blood lead concentrations that possibly have adverse effects on brain development of newborns with each potential risk factor. Maternal frequent use of tableware with color patterns inside was significantly associated with higher cord blood lead concentration in addition to the three items in the multiple linear regression analysis. These points should be considered as specific recommendations for maternal and fetal lead exposure in this city.

Adult↗

PubMed2006

Meteorologically adjusted ground level ozone trends in southern Taiwan.

Two methods were used to calculate the meteorologically adjusted ground level ozone trends in southern Taiwan. The first method utilized is a robust linear regression method. The second approach uses a multilayer perceptron (MLP) artificial neural network (ANN) method. The observations obtained from 16 monitoring stations were analyzed and divided into six groups by hierarchical divisive clustering procedure. The daily maximum 1 and 8 h ozone concentrations for each group are then calculated. The meteorologically adjusted trends obtained by linear regression and MLP methods are smaller than the unadjusted trends for all groups and average time. It indicts that the meteorological conditions in Taiwan tend to increase ambient ozone concentrations in recent years.

Environmental Monitoring↗

PubMed2002

Multivariate regression analyses of data from a randomised, double-blind, placebo-controlled study confirm quality of life benefit of epoetin alfa in patients receiving non-platinum chemotherapy.

Cancer-related anaemia is associated with a wide spectrum of symptoms that can negatively affect quality of life. Because epoetin alfa has demonstrated efficacy in correcting cancer-related anaemia, the impact of this treatment on quality of life was evaluated in a multinational, randomised, double-blind, placebo-controlled trial in 375 anaemic cancer patients receiving non-platinum-based chemotherapy. The cancer-specific measures of quality of life included the general scale (FACT-G Total) and fatigue subscale (FACT-An Fatigue subscale) of the Functional Assessment of Cancer Therapy-Anaemia and the Cancer Linear Analogue Scales measuring energy, ability to do daily activities, and overall quality of life. These measures were also used to examine the relationship between haemoglobin levels and quality of life. Both univariate and multiple linear regression analyses of quality of life data were performed. Results of the univariate analysis have been reported previously. The a priori-planned multiple linear regression analysis, which accounted for the effects of disease progression and several other possibly confounding variables on quality of life, showed a significant advantage for epoetin alfa over placebo for the five scales (all, P<0.05), and confirmed the results of the univariate analysis. For cancer-specific measures, significant correlations were demonstrated between baseline haemoglobin and quality of life (r, range: 0.14-0.26, all P<0.05) and between change in haemoglobin and change in quality of life (r, range: 0.26-0.34, all P<0.01). These findings provide evidence that increasing haemoglobin levels by epoetin alfa administration can significantly improve cancer patients' quality of life.

Activities of Daily Living↗

PubMed1997

Postradiotherapy PSA nadirs fail to support dose escalation study in patients with pretreatment PSA values < 10 ng/ml.

With three-dimensional conformal therapy, doses > 75 Gy have been delivered to the prostate with acceptable levels of morbidity; however, higher doses do appear to increase late gastrointestinal (GI) and genitourinary (GU) morbidity. Because patients with pretreatment prostate-specific antigen (PSA) values < 10 ng/ml can achieve 3-year actuarial bNED control rates of 90% after treatment with external beam radiotherapy to doses < 71 Gy, one might question the need for further dose escalation in this population. In this report, we examined the relationship between dose and PSA nadir for 90 patients with pretreatment PSA values < 10 ng/ml entered into a dose escalation study from March 1987 to October 1992. We wanted to see if nadir response data would predict a different outcome from our 3-year bNED control reports. All patients were treated with external beam radiotherapy to ICRU reporting point doses of 6,598 cGy to 7,895 cGy (median of 7,068 cGy). Minimum follow-up was 36 months (median, 47 months). Seven hundred thirty-nine posttreatment PSA nadir values were analyzed, yielding an average of 8.2 values per patient. Estimates of rates of bNED control and time to reach a posttreatment PSA of 1.0 ng/ml were calculated using the Kaplan-Meier product limit method. The log-rank test was used to evaluate differences in rates according to dose levels. Linear regression and Cox proportional hazard modeling were used to relate dose to bNED control on a continuum. Escalating doses from 66 to 79 Gy failed to increase the percentage of patients achieving nadir values < 1 ng/ml and similarly failed to increase the 3-year actuarial bNED control. Linear regression (P = .81) and the chi-square test of association (P = .23) supported the lack of a dose effect on nadir continuously and categorically, respectively, and the Cox regression model supported the conclusion that dose on a continuum has no effect on bNED control (P = .34). Furthermore, time to reach a posttreatment PSA level of 1.0 ng/ml was not statistically dependent on dose level (P = .13). Based on this study and prior reports demonstrating a dose response for late GI/GU morbidity, we question whether further dose escalation in this subgroup of patients is justified.

Biomarkers, Tumor↗

PubMed1998

Urinary excretion of the pyridinium cross-links of collagen in systemic lupus erythematosus.

The aim of this study was to measure the urinary excretion of the pyridinium cross-links of collagen and to determine their usefulness as markers of reduced bone mineral density in systemic lupus erythematosus (SLE). All female SLE patients managed at a single centre were invited to participate in a cross-sectional study of urinary pyridinium cross-links excretion (HPLC), bone mineral density (DXA), and SLE-related variables. Ninety-one women with SLE were studied, 35 of whom were postmenopausal. Pyridinoline/Creatinine (Pyd/Cr) and deoxypyridinoline/Cr (Dpd/Cr) levels in postmenopausal women were significantly increased compared with premenopausal values (p = 0.010 and p = 0.004, respectively). Univariate linear regression analysis revealed a significant association of Dpd/Cr with reduced femoral neck and lumbar spine BMD (p = 0.001, p<0.001), and of Pyd/Cr with reduced femoral neck BMD (p = 0.020). In addition, the association of Pyd/Cr with reduced lumbar spine BMD approached significance (p = 0.055). Stepwise multiple linear regression analysis adjusting for other variables confirmed a significant association of Dpd/Cr with reduced lumbar spine BMD (p = 0.006), and a significant association of both Pyd/Cr and Dpd/Cr with postmenopausal status (p = 0.003, p<0.001). It was concluded that in this SLE population, the urinary excretion of Dpd/Cr was a useful marker of reduced BMD at the lumbar spine. Menopausal status was a major predictor of cross-links excretion in SLE.

Absorptiometry, Photon↗

PubMed2005

Symmetry of fellow-eye intraocular pressure responses to topical glaucoma medications.

PURPOSE: One assumption of the uniocular drug trial in glaucoma management is that fellow-eye pairs exhibit symmetric intraocular pressure (IOP) responses when both eyes are treated with the same topical IOP-lowering medication. The purpose of this study was to determine if this assumption is true. DESIGN: Observational case series. PARTICIPANTS AND CONTROLS: Forty-three patients with bilateral glaucoma or ocular hypertension who underwent bilateral treatment with a topical IOP-lowering medication. METHODS: Patients were on 0 (81%) or 1 (19%) IOP-lowering medication at the time the medication was added in this study. Baseline IOP was the IOP at the treatment initiation visit, and IOP on treatment was assessed in both eyes on the first visit after addition of the medication. Linear regression of right-eye versus left-eye IOP reductions was performed. MAIN OUTCOME MEASURE: Correlation of right-eye and left-eye IOP responses to therapy. RESULTS: Right eyes demonstrated a 5.0-mmHg (26.9%) reduction, and left eyes demonstrated a 4.3-mmHg (23.7%) reduction. Linear regression of right-eye IOP reduction against left-eye IOP reduction gave a slope of 0.77 (Pearson correlation coefficient, r = 0.84; r2 = 0.70; P<0.0001). CONCLUSIONS: Fellow-eye pairs exhibited marked symmetry in IOP responses to IOP-lowering medications.

Administration, Topical↗

PubMedDate not supplied

Non-invasive assessment of baroreflex sensitivity and relation to measures of heart rate variability in man.

1. We have developed a simple noninvasive method to assess the spontaneous baroreflex (BRS; reflex heart rate response to change in systemic blood pressure) in man. The BRS is impaired in many cardiovascular disorders and is known to be of major prognostic significance; however, the invasive nature of traditional BRS assessment has thus far limited its clinical application. 2. Sixteen healthy subjects (7M, 9F; age 28 +/- 3 years) were studied at baseline and during stepwise i.v. infusion of phenylephrine and bolus i.v. dosing of nitroprusside. Invasive BRS was derived from linear regression of the change in systolic blood pressure (SBP) and RR interval from baseline following these perturbations. Noninvasive BRS was derived from approximately 1500 gated beat-to-beat SBP and RR interval data points acquired by Finapres BP and continuous ECG monitoring. Slopes were derived from linear regression of three consecutive baroreflex-mediated data points (following a phase shift of one RR interval from its accompanying SBP value) and were averaged to determine BRS. Correlations between invasive and noninvasive BRS measures were found to be highly significant (r = 0.78; P = 0.0009; slope = 0.87). 3. Significant correlations between noninvasively determined BRS and heart rate variability derived measures of autonomic activity (24h standard deviation of normal RR intervals, root mean square of successive RR intervals, low frequency and high frequency power) were also observed (r = 0.79-0.83; P = 0.003-0.008). 4. These results support the validity of this noninvasive method of measurement of BRS in man and of parasympathetic contribution to spontaneous baroreflex.

Adrenergic alpha-Agonists↗