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PubMed2002

Clinician change detection viewing longitudinal stereophotographs compared to confocal scanning laser tomography in the LSU Experimental Glaucoma (LEG) Study.

PURPOSE: To compare optic nerve head (ONH) surface change detection by confocal scanning laser tomography (CSLT) within the LSU Experimental Glaucoma (LEG) study to expert clinicians viewing the LEG stereophotographs. DESIGN: Experimental study. PARTICIPANTS: Four fellowship-trained glaucoma specialists. METHODS: In the LEG study, six 15 CSLT images (TopSS, Laser Diagnostics Technologies, San Diego, CA) and four 2x optic disc stereophotographs were obtained from both eyes of 12 monkeys on 3 separate days and then every 2 weeks after laser to one eye (study eye) to elevate intraocular pressure. ONH surface change detection within the CSLT images is described in our companion report. In this report, the preliminary study compared change detection by the CSLT multivariate strategy with that of a single clinician viewing stereophotograph pairs on three separate occasions as the "gold standard." The main study compared change detection by three additional clinicians viewing a subset of LEG stereophotograph pairs on three separate occasions with that of the CSLT multivariate strategy as the "gold standard." Clinician change detection was assessed for partial (two of three occasions) or complete (three of three occasions) agreement. Three comparison groups within the main study are emphasized: 44 group A comparisons assessed false-positive change detection (specificity); 38 group B comparisons assessed change detection within 38 instances (11 onset and 27 progression events) of CSLT-detected study eye change; and 30 group C comparisons assessed change detection within 30 instances in which the CSLT failed to detect change in study eyes. MAIN OUTCOME MEASURES: Clinician change detection within each comparison with either partial or complete agreement. RESULTS: Within the main study, intrareading (-.29 to 0.67) and interreading (0.24--0.56) session agreement for each clinician was slight to moderate by kappa test. Good specificity (less than 10% false-positive change detection) was achieved within the 44 group A comparisons by two of the three clinicians, but only when the more stringent criterion (change detection on three of three occasions) was applied. Of the 38 group B comparisons (in which the CSLT detected change), the two clinicians who achieved good specificity in group A failed to detect change in 25 and 16 instances, respectively, using the more stringent (three of three) criterion. Similarly, of the 30 group C comparisons (in which the CSLT failed to detect change), these two clinicians detected change in three and seven instances, respectively, but in only one comparison did they both detect change. CONCLUSIONS: This study provides the first direct evidence that an existing CSLT may reasonably meet or exceed the ONH surface change detection performance of fellowship-trained glaucoma specialists in at least those eyes with good CSLT reproducibility.

Animals↗
PubMed2000

Activity, dietary intake, and weight changes in a longitudinal study of preadolescent and adolescent boys and girls.

OBJECTIVE: To examine the role of physical activity, inactivity, and dietary patterns on annual weight changes among preadolescents and adolescents, taking growth and development into account. STUDY DESIGN: We studied a cohort of 6149 girls and 4620 boys from all over the United States who were 9 to 14 years old in 1996. All returned questionnaires in the fall of 1996 and a year later in 1997. Each child provided his or her current height and weight and a detailed assessment of typical past-year dietary intakes, physical activities, and recreational inactivities (TV, videos/VCR, and video/computer games). METHODS: Our hypotheses were that physical activity and dietary fiber intake are negatively correlated with annual changes in adiposity and that recreational inactivity (TV/videos/games), caloric intake, and dietary fat intake are positively correlated with annual changes in adiposity. Separately for boys and girls, we performed regression analysis of 1-year change in body mass index (BMI; kg/m(2)). All hypothesized factors were in the model simultaneously with several adjustment factors. RESULTS: Larger increases in BMI from 1996 to 1997 were among girls who reported higher caloric intakes (.0061 +/-.0026 kg/m(2) per 100 kcal/day; beta +/- standard error), less physical activity (-.0284 +/-.0142 kg/m(2)/hour/day) and more time with TV/videos/games (.0372 +/-.0106 kg/m(2)/hour/day) during the year between the 2 BMI assessments. Larger BMI increases were among boys who reported more time with TV/videos/games (.0384 +/-.0101) during the year. For both boys and girls, a larger rise in caloric intake from 1996 to 1997 predicted larger BMI increases (girls:.0059 +/-.0027 kg/m(2) per increase of 100 kcal/day; boys:.0082 +/-.0030). No significant associations were noted for energy-adjusted dietary fat or fiber. CONCLUSIONS: For both boys and girls, a 1-year increase in BMI was larger in those who reported more time with TV/videos/games during the year between the 2 BMI measurements, and in those who reported that their caloric intakes increased more from 1 year to the next. Larger year-to-year increases in BMI were also seen among girls who reported higher caloric intakes and less physical activity during the year between the 2 BMI measurements. Although the magnitudes of these estimated effects were small, their cumulative effects, year after year during adolescence, would produce substantial gains in body weight. Strategies to prevent excessive caloric intakes, to decrease time with TV/videos/games, and to increase physical activity would be promising as a means to prevent obesity.

Adolescent↗
PubMed2026

Longitudinal functional network connectivity changes across the clinical stages of C9orf72 hexanucleotide repeat expansion carriers.

INTRODUCTION: Intrinsic functional connectivity network abnormalities in C9orf72 hexanucleotide repeat expansion carriers emerge during the asymptomatic phase, yet longitudinal studies remain limited. We examined cross-sectional abnormalities and longitudinal connectivity changes across clinical stages. METHODS: We analyzed task-free functional magnetic resonance imaging (fMRI) and structural MRI data in 36 asymptomatic (aSxC9), 17 prodromal (proC9), and 29 symptomatic (SxC9) carriers, and 107 healthy controls (HCs). Functional networks previously found altered in C9orf72, including salience, sensorimotor, default mode, and medial pulvinar thalamic networks, were examined. Associations between longitudinal connectivity and gray matter decline with baseline neurofilament light chain (NfL) concentrations and symptom severity were assessed. RESULTS: aSxC9 and SxC9 showed longitudinal connectivity changes within specific networks. In aSxC9, connectivity changes correlated with baseline NfL. In proC9 and SxC9, changes in connectivity and gray matter were associated with baseline NfL and symptom severity. DISCUSSION: C9orf72 expansion carriers demonstrate stage-specific network connectivity changes.

Humans↗
PubMed2005

Longitudinal volumetric MRI change and rate of cognitive decline.

OBJECTIVE: To examine how baseline and change of volumetric MRI relate to cognitive decline in older individuals. BACKGROUND: Memory is associated with hippocampal integrity, whereas executive function has been linked to impaired frontal lobe function. Previous studies have shown that hippocampal and cortical atrophy are more strongly related to cognition than are measures of subcortical cerebrovascular disease (CVD). The authors hypothesized that memory (MEM) decline would be related to change in hippocampal volume (HC), whereas decline in executive function (EXEC) would be related to change of cortical gray matter volume (CGM) and measures of subcortical CVD. METHODS: Subjects from a multicenter study (n = 103) included cognitively normal, mildly impaired, and demented cases with and without subcortical lacunes. All had longitudinal cognitive evaluation (mean = 4.8 years) and two or more MRI scans at least one year apart (mean = 3.4 years). MRI measures included HC, CGM, total lacune volume (LAC), and white matter hyperintensity volume (WMH). Random effects modeling of longitudinal data assessed effects of MRI baseline and MRI change on baseline and change of psychometrically matched measures of MEM and EXEC. RESULTS: Change in MEM was related to HC baseline and HC change. Change in EXEC was related to baseline CGM and to change in CGM, HC, and LAC. Results were unchanged when demented cases were excluded. WMH was not associated with change in MEM or EXEC independent of HC, CGM, and LAC. CONCLUSION: Hippocampal volume was the primary determinant of memory decline, whereas executive function (EXEC) decline was related to multiple brain components. Results support a hypothesis that MEM decline is strongly influenced by Alzheimer disease (AD), whereas EXEC decline may be complexly determined by cerebrovascular disease and AD.

Aged↗
PubMed1998

Longitudinal dental arch changes in adults.

This study examined changes in the dental arches that occur in untreated persons between late adolescence and the fifth or sixth decade of life. Longitudinal dental casts from 82 subjects were obtained as part of a recall study of subjects from the University of Michigan Elementary and Secondary School Growth Study. From the parent sample, three groups were identified. The untreated sample comprised 53 subjects (27 males and 26 females). A midadult sample of 10 persons, who had an additional set of records taken on average during their fourth decade of life also was analyzed, as was a sample of 13 subjects who received orthodontic treatment as adolescents and were about 30 years posttreatment. Measures of dental arch width, arch depth, and arch perimeter were evaluated with the aid of digital-imaging hardware and software. Incisor irregularity, curve of Spee, overjet, and overbite were measured directly from the dental casts. Statistically significant decrements occurred in arch width, depth, and perimeter. The mean decrement in any one dimension was less than 3 mm. At all times, males displayed significantly more mandibular incisor irregularity than females. In addition, the increase in mandibular incisor irregularity that occurred in male and female subjects was the same. However, irregularity did not increase in all subjects; it decreased in 3% of the males and 7% of the females. In general, overbite, overjet, and curve of Spee were stable during adulthood. Statistically significant correlations between the changes in dental arch measures could not be established.

Adolescent↗
PubMed1998

Marriage and the parenting alliance: longitudinal prediction of change in parenting perceptions and behaviors.

The study evaluates how marriage and the parenting alliance affect parenting experiences over time. Couples (N = 79) with school-age children who have mental retardation completed self-report and observational measures of marriage, the parenting alliance, and parenting attitudes and behaviors at 2 periods, 18-24 months apart. Longitudinal structural equation modeling demonstrated significant effects of marital quality on changes over time in self-reports of perceived parenting competence for both the mothers and the fathers, and in observed negative mother-child interactions. Also, in all cases, the parenting alliance mediated the effects of marriage on parenting experiences. There was little evidence of reciprocal causation in which parenting variables predicted change in the quality of marriage and the parenting alliance. Interactions involving child age suggested that teenagers as opposed to younger children were more reactive to negative features of their parents' marital functioning and parenting alliance. Implications are discussed regarding stable but negative marital functioning and regarding possible differences in mothers' and fathers' parenting in the context of marital distress.

Adolescent↗
PubMed2002

Longitudinal analysis of changes in indices of obesity from age 8 years to age 18 years. Project HeartBeat!

To compare growth patterns of obesity indices derived from body composition and anthropometric measures, the authors analyzed data from Project HeartBeat!, a longitudinal study of cardiovascular disease risk factors in childhood and adolescence. A total of 678 children initially aged 8, 11, and 14 years in The Woodlands and Conroe, Texas, were enrolled and followed with 4-monthly examinations between October 1991 and August 1995. Trajectories of change from age 8 years to age 18 years were estimated for body mass index, percent body fat, abdominal circumference, the sum of two skinfolds, and the sum of six skinfolds. All indices varied importantly with age. Percent body fat, sum of two skinfolds, and sum of six skinfolds shared similar growth patterns, with strong divergence between males and females. Males' body fat decreased with age and females' increased or remained nearly constant with age. In contrast, both body mass index and abdominal circumference increased monotonically with age in both sexes, exhibiting little sex difference as children reached late adolescence. Sex differences were more striking among Blacks than among non-Blacks. The authors conclude that growth patterns of adiposity differ according to the measure chosen. Furthermore, changes in different obesity indices may not relate in the same way to changes in blood pressure or blood lipid concentrations.

Adolescent↗
PubMed1985

Longitudinal serum lipoprotein changes in white males during adolescence: the Bogalusa Heart Study.

Determinants of follow-up levels of low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C) and the ratio of LDL-C to HDL-C were analyzed in a longitudinal study. White boys (n = 81) aged 11 to 12 years, when examined in 1973-1974 (year 1) were reexamined in 1978-1979 (year 6) at ages 16 to 17 years. During follow-up, mean levels of LDL-C increased from 87.6 mg/dL to 89.8 mg/dL, mean levels of HDL-C decreased from 67.0 mg/dL to 48.4 mg/dL and the mean LDL-C/HDL-C ratio increased from 1.45 to 2.12. Cross-sectional associations between the serum lipoproteins and weight, triceps skinfold thickness, and ponderosity (wt/ht3) were stronger in year 6 than in year 1. A persistence of ranks was observed between year 1 and year 6 for LDL-C (r = 0.61), HDL-C (r = 0.51), and LDL-C/HDL-C (r = 0.50). Multiple linear regression indicated that year 6 LDL-C levels were positively related to year 1 LDL-C, year 1 Tanner stage (an indication of sexual maturation), and the change in skinfold thickness during follow-up. Follow-up LDL-C/HDL-C was related both to change in height (negatively) and to change in weight (positively), after controlling for year 1 LDL-C/HDL-C. These longitudinal findings were similar to those obtained from earlier cross-sectional analyses and were further verified on an independent cohort of white boys also followed for five years (1976-1977 through 1981-1982).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed2004

Reduced NAA in motor and non-motor brain regions in amyotrophic lateral sclerosis: a cross-sectional and longitudinal study.

OBJECTIVES: After replication of previous findings we aimed to: 1) determine if previously reported (1)H MRSI differences between ALS patients and control subjects are limited to the motor cortex; and 2) determine the longitudinal metabolic changes corresponding to varying levels of diagnostic certainty. METHODS: Twenty-one patients with possible/suspected ALS, 24 patients with probable/definite ALS and 17 control subjects underwent multislice (1)H MRSI co-registered with tissue-segmented MRI to obtain concentrations of the brain metabolites N-acetylaspartate (NAA), creatine, and choline in the left and right motor cortex and in gray matter and white matter of non-motor regions in the brain. RESULTS: In the more affected hemisphere, reductions in the ratios, NAA/Cho and NAA/Cre+Cho were observed both within (12.6% and 9.5% respectively) and outside (9.2% and 7.3% respectively) the motor cortex in probable/definite ALS. However, these reductions were significantly greater within the motor cortex (P<0.05 for NAA/Cho and P<0.005 for NAA/Cre+Cho). Longitudinal changes in NAA were observed at three months within the motor cortex of both possible/suspected ALS patients (P<0.005) and at nine months outside the motor cortex of probable/definite patients (P<0.005). However, there was no clear pattern of progressive change over time. CONCLUSIONS: NAA ratios are reduced in the motor cortex and outside the motor cortex in ALS, suggesting widespread neuronal injury. Longitudinal changes of NAA are not reliable, suggesting that NAA may not be a useful surrogate marker for treatment trials.

Aged↗
PubMed1989

Alzheimer's disease: longitudinal CT studies of ventricular change.

A 3-year longitudinal study was conducted with 50 Alzheimer's disease patients and 45 elderly control subjects. All study participants received an extensive evaluation that included brain CT at baseline and follow-up. Quantitation of ventricular size, using both linear and volume methods, revealed highly significant cross-sectional and longitudinal differences between the Alzheimer patients and control subjects. Specifically, the annual rate of change in ventricular volume was approximately 9% in the Alzheimer patients and approximately 2% in the controls. The presence of age-related white matter lesions had no effect on the clinical course of the patients or on the changes in ventricular size. Among the Alzheimer patients, the rate of clinical decline was strongly related to the rate of change in ventricular size. Baseline ventricular measurements were of no value in predicting the subsequent rate of clinical deterioration or ventricular enlargement. The results suggest that changes in ventricular size closely reflect the clinical changes in Alzheimer patients.

Aged↗
PubMed2003

Longitudinal assessment of changes in HIV-specific effector activity in HIV-infected patients starting highly active antiretroviral therapy in primary infection.

Both the magnitude and breadth of HIV-specific immunity were evaluated longitudinally on samples collected from six subjects starting highly active antiretroviral therapy (HAART) preseroconversion (group 1), 11 recently infected subjects starting HAART postseroconversion (group 2), five subjects starting HAART in the second half of the first year of infection (group 3), and six persons starting treatment in the chronic phase of infection (group 4). HIV-specific immunity was measured by IFN-gamma ELISPOT, detecting the frequency of cells responding to a panel of HLA-restricted HIV-1 peptides. Intracellular cytokine staining was used to detect the frequency of HIV-1 Gag p55-specific CD4(+) and CD8(+) T cells in a subset of participants. The magnitude and breadth of HIV-specific responses persisted in all group 1 subjects and in 5 of 11 (45%) group 2 subjects. Both of these parameters declined in 6 of 11 (55%) group 2 and in all group 3 and 4 individuals. All persons who maintained detectable numbers of HIV-1 Gag p55-specific CD4(+) and CD8(+) T cells after starting HAART preserved the intensity and breadth of their HIV-specific effector response. Our results show that HIV-specific immunity can be preserved even if HAART is initiated beyond the acute phase of infection.

Adult↗
PubMedDate not supplied

A longitudinal study of cellular changes in experimental otitis media.

A longitudinal sequential study of otitis media in an experimental animal (cat) using eustachian tube obstruction was done. Fifty animals were used. The continuum of mucoperiosteal changes from one day to six months after obstruction revealed gradual changes that were similar for each animal. Stages were defined, and by using different staining techniques, including immunocytochemistry, an overall middle ear defense system was postulated and documented. Nonspecific as well as specific defense systems, including localized immunity, were described. Effusions were studied in a continuum, and their pathogenesis was discussed.

Animals↗
PubMed1983

Changing expectations: a longitudinal study of community attitudes toward a nuclear power plant.

Initial and 5-year follow-up interviews were conducted with 213 residents of the host community for a nuclear power plant. The purpose was to determine possible changes in attitudes toward the plant and expectations about potential outcomes associated with construction. Large negative changes in attitudes toward the plant were noted and were accompanied most notably by decreased expectations of positive outcomes. The structure of the expectations remained essentially stable over the 5-year period. Perceptions of hazards, community disruption, and economic benefits as measured early in construction and during peak construction were found to be the best predictors of acceptance of the nuclear plant. Initial expectations were found to predict overall attitude toward the plant 5 years later. Results were discussed in terms of implications for social impact assessment, large-scale community change, and the predictability of community attitudes toward nuclear power plant construction.

Female↗
PubMed1993

Change detection on longitudinal data in periodontal research.

Longitudinal data of attachment level (AL) or the alveolar bone level are often used to assess the progression of periodontal disease. This paper tries to identify the most efficient method to detect the changes of AL in a general periodontal research environment; that is, a sequential decision based on multiple sites. Several existing methods suggested in the periodontal research literature such as the tolerance, running median, cusum, and regression methods as well as change-point detection methods in the statistical literature are examined. It is found that the regression method is most convenient among the several methods that are equally effective in change detection. Formulae, tables and their usage are discussed in detail.

Decision Support Techniques↗
PubMed2005

Impact of the longitudinal and seasonal changes of the water quality on the benthic macroinvertebrate assemblages of the Andorran streams.

The ecological quality of the Andorran streams was assessed in 1998-1999, based on the survey of the water chemistry and the benthic macroinvertebrate assemblages. Two types of modification of the water quality were observed in the Andorran rivers: (i) a progressive degradation along the longitudinal gradient with a chronic degradation in the lower water courses; (ii) a seasonal modification in the mid-elevation sites. Two responses of the benthic macroinvertebrate assemblages to these disturbances were observed: an extreme simplification of the composition and a change of the trophic structure of the assemblages in the more impacted sites.

Andorra↗