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At least 415 records · Page 23Linked to original sources
PubMed2004

Longitudinal change in quality of life and impact on survival after left ventricular assist device implantation.

BACKGROUND: The HeartMate vented electric left ventricular assist device has been approved for use as destination therapy. Thus, the study of quality-of-life outcomes, as well as morbidity and mortality, is imperative. The purpose of our study was to describe change with time (from 1 month to 1 year) in patients who received a HeartMate vented electric left ventricular assist device as a bridge to heart transplantation and to identify quality-of-life predictors of survival after left ventricular assist device implantation. METHODS: A nonrandom sample of 78 patients who received a HeartMate vented electric left ventricular assist device (primarily middle-aged, white married males) who had quality-of-life data at 1, 2, 3, 6, 9, or 12 months after implant was the subject of this report. The sample size decreased with time primarily because of heart transplantation. Patients completed the following booklets of questionnaires: Quality of Life Index, Rating Question Form, Heart Failure Symptom Checklist, and Sickness Impact Profile. Analyses included both descriptive analyses and modeling procedures (mixed-effects models and Cox proportional hazards models). RESULTS: Quality-of-life outcomes were fairly good and stable from 1 month to 1 year after HeartMate vented electric left ventricular assist device implantation. Both positive and negative changes were detected in all quality-of-life domains (physical and occupational function, social interaction, somatic sensation, and psychological state) after left ventricular assist device insertion. Items from the physical domain of quality of life, specifically walking and dressing oneself, were significantly associated with the risk of dying after left ventricular assist device implantation. CONCLUSIONS: Identifying poor quality-of-life outcomes within 1 year after left ventricular assist device implantation provides direction to develop strategies to improve outcomes. Physical and occupational rehabilitation, psychosocial intervention, and monitoring symptom distress and physical disability may contribute to improved quality-of-life outcomes and survival after left ventricular assist device implantation.

Adult↗
PubMed2007

Predicting inadequate long-term lung development in children with congenital diaphragmatic hernia: an analysis of longitudinal changes in ventilation and perfusion.

PURPOSE: Infants born with congenital diaphragmatic hernia (CDH) demonstrate a wide variability in postnatal catch-up lung growth. The goals of this study were to assess the pulmonary development of children born with CDH using sequential ventilation-perfusion (V/Q) scintigraphy and to identify the perinatal factors that correspond to a progressive V/Q mismatch. METHODS: The records of 137 patients seen between 1990 and 2005 in a multidisciplinary CDH clinic were reviewed. Changes in the ipsilateral V/Q quotient were compared in 46 patients who had 2 or more studies with the following variables: sex, patch repair, laterality, gestational age, and use of extracorporeal membrane oxygenation. An abnormal V/Q quotient was defined as greater than 1.2 (reference range, 0.8-1.2). RESULTS: Abnormal V/Q scans were identified in 28 (61%) of the 46 patients at the time of the last V/Q study. Patients who underwent a patch repair had nearly 7 times the risk (P < .001) of developing an ipsilateral V/Q mismatch. The use of extracorporeal membrane oxygenation had a variable effect on the probability of an abnormal V/Q study finding. No other variable was significant. CONCLUSIONS: Many children with CDH develop significant and progressive V/Q mismatches. Although some perinatal variables appear to be predictive of this phenomenon, they may simply be surrogates for a greater degree of pulmonary hypoplasia present at birth. This subpopulation of CDH survivors is an identifiable group clearly at risk and thus requires long-term follow-up.

Adolescent↗
PubMed2006

Longitudinal changes in hyperinflation parameters and exercise capacity after giant bullous emphysema surgery.

OBJECTIVE: Although resection of giant bullae for the purpose of improving the function of underlying compressed lung is an accepted form of surgery for emphysema, there is only limited information regarding long-term improvement in dynamic hyperinflation and exercise tolerance. Our major goal was to investigate the effects of lung resection for giant bullae on pulmonary function, dynamic hyperinflation, and exercise capacity in patients with chronic obstructive pulmonary disease characterized by emphysema. METHODS: Pulmonary function and exercise testing were assessed prospectively before and 3, 6, 12, 24, and 48 months after surgery in 12 patients who had chronic obstructive pulmonary disease with emphysema who underwent lung resection of giant bullae. RESULTS: Forced expiratory volume, diffusing capacity for carbon monoxide, arterial partial pressure of oxygen, and exercise capacity were significantly increased after resection of surgical bullae. Dynamic hyperinflation, as assessed by reduction in inspiratory capacity and dyspnea Borg scale, were significantly decreased during exercise. Improvement in baseline and exercise functional capacity slightly decreased over time, remaining, however, far above the value before surgery. CONCLUSION: Altogether, these findings suggest that surgery for resection of giant bullae is an effective procedure for improving airflow, limiting gas exchange, and limiting exercise dynamic hyperinflation over time.

Aged↗
PubMed2004

One-year analysis of longitudinal changes in spirometry in patients with COPD receiving tiotropium.

BACKGROUND: Airway medications have not been shown to reduce the loss of lung function in patients with COPD. We explored whether tiotropium 18 microg once daily could slow the rate of decline of lung function over a 1-year period. METHODS: We performed a post-hoc analysis of data from 921 ambulatory COPD patients participating in two, 1-year, double-blind, tiotropium vs. placebo-controlled trials. Serial spirometry was obtained at baseline (before first dose of study drug), on day 8, at 6 weeks, and at 3, 6, 9 and 12 months after start of the study. RESULTS: Baseline demographics and lung function were comparable. Baseline FEV1 was 1.01+/-0.41 (SD) L (39+/-14% predicted). Mean decline in trough FEV1 (i.e. FEV1 23-24 h after prior use of medication) between days 8 and 344 was 58 ml/year in the placebo group and 12 ml/year in the tiotropium group (p=0.005 vs. placebo); and between days 50 and 344 was 59 ml/year in the placebo group and 19 ml/year in the tiotropium group (p=0.036 vs. placebo). CONCLUSIONS: Based on a retrospective analysis of 1-year, placebo-controlled clinical trials, tiotropium was associated with a reduced rate of loss of FEV1. Longer-term trials specifically designed to study this effect are required to confirm this observation.

Administration, Inhalation↗
PubMed2005

Longitudinal changes of optical aberrations in normal and form-deprived myopic chick eyes.

We performed measurements of refraction (with retinoscopy), axial length (with ultrasound biometry) and ocular aberrations (with a custom-built Hartmann-Shack aberrometer) on seven awake White-Leghorn chicks occluded monolaterally with diffusers for two weeks. Treatment started on the first day after hatching (day 0) and measurements were conducted on several days between day 0 and 13. Non-occluded eyes experienced normal emmetropization (decreasing hyperopia at 0.2 +/- 0.09 D/day and increasing axial length at 0.05 +/- 0.03 mm/day), while occluded eyes developed axial myopia (1.50 +/- 0.2 D/day and 0.12 +/- 0.02 mm/day). Interocular differences in refraction and axial length by day 13 were on average 17.43 D and 0.86 mm, respectively. Monochromatic high order aberrations decreased with age in both eyes. Average RMS (for 1.5 mm pupil diameter) decreased from 0.11 +/- 0.03 at day 0 to 0.06 +/- 0.03 microm (day 13) in occluded eyes, and from 0.12 +/- 0.05 to 0.03 +/- 0.01 microm in non-occluded eyes. MTF-based optical quality metrics also show an improvement with age. However, while this improvement occurs in both eyes, after day 8 myopic eyes tend to show significantly higher amounts of aberrations (and consequently worse best-corrected optical quality) than normal eyes. The degradation imposed by aberrations is small compared to that imposed by defocus and the diffuser. These results suggest a decrease of aberrations during development which does not seem to be visually guided. Myopic eyes showed slightly worse optical quality than normal eyes, suggesting that the geometrical changes resulting from excessive ocular axial growth also affect the optical quality of the ocular components.

Animals↗
PubMed1999

Longitudinal changes and prognostic implications of left ventricular diastolic function in first acute myocardial infarction.

BACKGROUND: Left ventricular (LV) diastolic dysfunction contributes to signs and symptoms of clinical heart failure and may be related to prognosis in heart diseases. LV diastolic dysfunction is reported to be present in acute myocardial infarction (MI); however, little is known about the time course of changes in LV diastolic function and its relation to prognosis after acute MI. METHODS AND RESULTS: Two-dimensional and Doppler echocardiographic examinations were performed in 58 consecutive patients with first acute MI. The patients were studied serially within 1 hour and at days 5, 90, and 360 after arrival to the coronary care unit. LV diastolic function was assessed by Doppler measurements of transmitral and pulmonary venous flow. On the basis of mitral inflow, patients with MI were stratified at baseline to 3 LV diastolic filling patterns: normal, impaired relaxation, or pseudonormal/restrictive. Patients with MI were observed for development of congestive heart failure (Killip class >I) during hospitalization and for death during 1-year follow-up, and these complications were related to LV diastolic function. LV diastolic dysfunction was present in the very early phase of acute MI, with signs of impaired relaxation or restrictive LV filling dynamics in 38% and 24% of the patients, respectively, whereas 38% had normal LV filling characteristics. Impaired relaxation of the LV was most pronounced and found in 60% after 1-year follow-up. In-hospital congestive heart failure (Killip class >I) was found in 50% of the patients with initial impaired LV relaxation and in 71% of the patients with initially pseudonormal or restrictive LV filling dynamics, whereas patients with normal LV filling were free of heart failure. Patients with initial impaired relaxation and restrictive LV filling dynamics demonstrated a significant LV dilation during 1-year follow-up. Patients with initial pseudonormal/restrictive LV filling pattern were more frequently readmitted to the hospital for heart failure and had significant higher New York Heart Association class score compared with patients with normal or impaired relaxation during follow-up. Cardiac death was (n = 6) only observed in patients with pseudonormal or restrictive LV filling pattern. In a multivariate stepwise regression analysis, mitral E deceleration time </=140 ms and age were identified as independent variables related to development of in-hospital congestive heart failure and cardiac death during 12 months of follow-up. CONCLUSIONS: LV diastolic dysfunction is present in the very early phase of MI. LV remodeling and development of in-hospital congestive heart failure appear in patients with very early signs of LV diastolic dysfunction. Furthermore, mitral E deceleration time </=140 ms best identified patients at risk of development of in-hospital congestive heart failure and cardiac death after MI.

Adult↗
PubMed1997

Longitudinal changes in axial length in pseudophakic children.

PURPOSE: To evaluate the axial length changes that occur in children 3 to 9 years of age who had cataract extraction with primary intraocular lens (IOL) implantation. SETTING: Emory Eye Center, Emory University, and Egleston Children's Hospital, Atlanta, Georgia, USA. METHODS: A review of 17 eyes in 15 children (mean age 6.4 years; range 3 to 9 years) who had primary IOL implantation was undertaken. Patients were followed for an average of 3.1 years. The initial and final axial length measurements and refractive errors were compared. RESULTS: The overall change in mean axial length in the 17 eyes was 0.64 mm. The overall mean myopic shift was -1.01 diopters (D) (range -3.00 +0.50 D). Eyes with traumatic cataracts experienced more axial elongation than eyes with developmental/congenital cataracts (0.97 mm versus -0.01 mm; P = .03). Ninety-four percent of patients obtained a final visual acuity of 20/40 or better. CONCLUSION: Eyes with traumatic cataracts experienced more axial elongation than eyes with developmental/congenital cataracts after cataract extraction and IOL implantation.

Cataract↗
PubMed2002

A regression model for longitudinal change in the presence of measurement error.

PURPOSE: The analysis of change in measured variables has become quite popular in studies where data are collected repeatedly over time. The authors describe some of the potential pitfalls in the analysis of change when the variable for change is measured with error. They show that regression analysis is often biased, possibly leading to erroneous results. METHODS: A simple method to correct for measurement error bias in regression models that model change is presented. RESULTS AND CONCLUSIONS: The two examples illustrate how measurement error can adversely affect an analysis. The bias-corrected approach yields valid results.

Aged↗
PubMed2002

Longitudinal changes in the time parents spend in activities with their adolescent children as a function of child age, pubertal status, and gender.

This study examined the time Dutch mothers (N = 301) and fathers (N = 255) spend per day engaging in 4 activities (going somewhere, doing something, watching TV, and eating together) with their adolescent children both concurrently and 5 years later. Also assessed was whether parent-child shared time was related to parent or child gender and whether age-related differences could be explained by adolescent pubertal status, family conflict, adolescent and parent work or volunteer hours, parental work stress, and adolescent computer use. Finally, the study examined whether family conflict predicted changes in shared time and whether shared time predicted changes in conflict. The findings showed that age changes depended on the activity and that pubertal status mediated age differences in TV viewing among mixed-gender parent-child pairs. Shared time during pre-, early, and mid-adolescence was linked to decreases in family conflict 5 years later.

Adolescent↗
PubMed1998

Longitudinal changes in Class I subjects with moderate mandibular skeletal protrusion.

Two groups of Class I females were followed from 6 to 18 years of age. At the initial evaluation, subjects in one group had normal sagittal jaw-base relationships, while those in the other group had moderate mesial relationships between the jaw bases. The purpose of this study was to compare craniofacial morphology and growth in these two groups. Subjects with mesial jaw-base relationships had mandibular skeletal protrusion due to a more forward positioning of the mandible relative to anterior cranial base. Other morphological group differences involved jaw-base relationships (but not jaw size). All the observed group differences were present at age 6; no new differences were observed later. Some differences stayed significant up to age 18, while others became less distinct with time. Incremental growth in the groups was comparable. Similar growth of the jaws apparently helped to maintain initial group differences in jaw-base relationships.

Cephalometry↗
PubMed1997

Longitudinal changes of bone mineral density and bone turnover in postmenopausal women on thyroxine.

OBJECTIVE: The skeletal risks of subclinical hyperthyroidism in postmenopausal women on replacement thyroxine remain controversial. The aims of this study were to determine (1) the relationship between bone turnover and TSH levels and (2) whether reduction of thyroxine (T4) dose in postmenopausal women who have suppressed TSH levels is beneficial to bone mineral density (BMD) and bone turnover. DESIGN: A prospective study over 2 years of post-menopausal women treated with T4 with an age- and sex-matched healthy control group. PATIENTS AND MEASUREMENTS: Sixty-four post-menopausal women, ages 47 to 74 (61 +/- 9, mean +/- SD), on T4 for between 2 and 14 years. Patients were divided into three groups: group 1 (n = 23) with normal serum TSH levels, group 2 (n = 18) with suppressed serum TSH levels and group 3 (n = 23) with a history of thyroidectomy and suppressed TSH levels (patients with thyroid cancer). Thirty-six age-matched healthy postmenopausal women were recruited as a control group. Bone mineral density (BMD), measured by dual-energy X-ray absorptiometry and bone turnover, were evaluated at baseline and over 2 years in the four groups. Serum TSH levels were measured every 6 to 12 months. In group 2, the dose of T4 was reduced after the baseline measurement and serum TSH levels were remeasured 1 to 4 months later. Serum TSH levels returned to the reference range after the reduction of T4 dose in group 2. RESULTS: The serum TSH level, after log transformation, was negatively correlated with serum levels of osteocalcin (BGP), bone alkaline phosphatase (BAP) and urinary cross-linked N-telopeptides pyridinoline of type I collagen (NTx) (linear correlation, r = -0.41 P < 0.001, r = -0.29 P = 0.01 and r = -0.26 P = 0.033), respectively. There was no significant difference in BMD and bone turnover between the four groups at either baseline or follow-up (ANOVA, P > 0.05). The levels of serum BGP, BAP and urinary NTx decreased whereas lumbar spine and femoral neck BMD increased significantly in group 2 over 2 years (one sample t-test, P = 0.0021, 0.034, 0.0017, 0.011 and < 0.001, respectively). In group 2, the rates of change of lumbar spine and femoral BMD were increased significantly and the rates of change of serum BGP and urinary NTx were decreased significantly compared with other groups (Scheffe test, P < 0.05). CONCLUSIONS: In postmenopausal women on T4, bone turnover is related to the serum TSH level and a reduction of T4 dose in those with suppressed serum TSH levels can result in a decrease in bone turnover and an increase in bone mineral density.

Aged↗
PubMed2006

Longitudinal change in perceptual and brain activation response to visceral stimuli in irritable bowel syndrome patients.

BACKGROUND & AIMS: Symptom-related fears and associated hypervigilance toward visceral stimuli may play a role in central pain amplification and irritable bowel syndrome (IBS) pathophysiology. Repeated stimulus exposure leads to decreased salience of threat and reduction of hypervigilance. We sought to evaluate hypervigilance in IBS visceral hypersensitivity and associated brain activity. METHODS: Twenty IBS patients (14 female; moderate to severe symptoms) and 14 healthy controls participated in symptom and rectal distention assessments 6 times over 12 months. In a subset of 12 IBS patients, H2 15O-positron emission tomography images were obtained during baseline, rectal distentions, and anticipation of an aversive distention during the first and last session. Statistical parametric mapping (SPM99) was used to identify areas and networks activated during each session as well as those with differential activation across the 2 sessions. RESULTS: Perceptual ratings of the rectal inflations normalized over 12 months, whereas IBS symptom severity did not. There were no sex-related differences in these response patterns. Stable activation of the central pain matrix was observed over 12 months, and activity in limbic, paralimbic, and pontine regions decreased. During the anticipation condition, there were significant decreases in amygdala, dorsal anterior cingulate cortex, and dorsal brainstem activation at 12 months. Covariance analysis supported the hypothesis of changes in an arousal network including limbic, pontine, and cortical areas underlying the decreased perception seen over the multiple stimulations. CONCLUSIONS: In IBS patients, repeated exposure to experimental aversive visceral stimuli results in the habituation of visceral perception and central arousal, despite stable activation of networks processing visceral pain and its anticipation.

Abdominal Pain↗
PubMed2003

Dissolution and absorption modeling: model expansion to simulate the effects of precipitation, water absorption, longitudinally changing intestinal permeability, and controlled release on drug absorption.

A previously described model for simulating drug dissolution, absorption, and pharmacokinetics has been expanded beyond the original application of simulating immediate-release dosage forms to include simulation of drug precipitation, water absorption from the gastrointestinal tract, changing gastrointestinal permeability, disintegration, and controlled-release and dissolution from a GITS-type dosage form. A mathematical description of the model is presented as well as a retrospective analysis of nifedipine to demonstrate the utility of the model. The fourth-order Runge-Kutta numerical method was used to solve the series of coupled differential equations used to simulate the process of dissolution, absorption, and drug disposition. The model was able to simulate the clinically demonstrated effect for drug particle size on nifedipine plasma concentrations for an immediate-release dosage form. Further simulations indicated that drug particle size was less important for a GITS-type dosage form at a release rate of 1.7 mg/hr compared to rate of 17 mg/hr. Hypothetical calculations simulated the potential effect of drug precipitation, water absorption, and changing permeability on drug plasma concentrations. The expanded model increases the utility of a previously described model in providing guidance in drug development and selection.

Biological Availability↗
PubMed2000

Longitudinal changes in CD4+ T cell antigen receptor diversity and naive/memory cell phenotype during 9 to 26 months of antiretroviral therapy of HIV-infected patients.

Although skewing of the CD4+ TCR repertoire in advanced HIV infection is well documented, increases in polyclonality during antiretroviral therapy have been less consistently observed. Ten patients, each with documented abnormalities within the CD4+ TCR repertoire, were studied by CDR3 spectratyping, semiquantitative PCR, and SSCP during 9-26 months of therapy. Naive and memory cell phenotypes were analyzed by flow cytometry. Six of 10 patients showed increased polyclonality of their TCR repertoires, 1 showed no change, and 3 showed increased TCR skewing, despite suppressed viral replication. Overall, there was no significant change in the percentage of abnormal BV subfamilies (from a mean of 25.5 to 17.1%) or the percentage of naive CD4+ T cells (from a mean of 18 to 25%). Further, progression of TCR repertoire disruptions was observed in some patients even with suppression of plasma viral RNA below 500 copies/ml. Although a spectrum of changes may be seen within the CD4+ TCR repertoire in the setting of antiretroviral therapy, increases in polyclonality are observed in some patients.

Anti-HIV Agents↗