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At least 19 recordsLinked to original sources
PubMed1994

Longitudinal changes in IQ among fragile X females: a preliminary multicenter analysis.

Longitudinal declines in IQ among fragile X [fra(X)] males have been reported previously by several investigators. Remarkably little is known about longitudinal changes in IQ scores among fra(X) females. Previously, one cross-sectional study showed a significant negative correlation between age and IQ scores. However, a recent investigation of girls with fra(X) syndrome noted longitudinal increases in IQ scores in 8 of 11 individuals. Therefore, the purpose of this preliminary multicenter study was to determine: (1) the characteristics of longitudinal changes in IQ among fra(X) females; and (2) whether these changes were comparable to those which have been observed among fra(X) males. IQ test and retest scores for 11 fra(X) females were obtained from 3 centers: Greenwood, South Carolina; Ibaraki, Japan; and Leuven, Belgium. To ensure high reliability, only test-retest scores from the Wechsler and Stanford-Binet tests were used. Age of subjects at initial testing ranged from 5 to 35 years. Mean intertest interval was 4.5 years. In contrast to a report of longitudinal increases, we found 9/11 (82%) subjects demonstrated decreases in IQ scores. Mean decline was 9 points. Females over 18 years of age showed little or no change in IQ scores. Decreases in scores appeared to be related to initial IQ score. Females in the earlier longitudinal report were higher functioning than those in our study, which may account for the observed difference in direction of change; or, change in IQ score may be related to size of the fra(X) mutation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

Longitudinal changes in insulin release and insulin resistance in nonobese pregnant women.

To assess the longitudinal changes in insulin release and insulin sensitivity in nonobese normal women during gestation, six women were evaluated with oral glucose tolerance testing, body composition analysis, intravenous glucose tolerance tests, and the hyperinsulinemic-euglycemic clamp before conception, at 12 to 14 weeks, and at 34 to 36 weeks' gestation. There was a significant increase in the insulin/glucose ratio (p = 0.028) during the oral glucose tolerance test during gestation. There was also a significant 3.0- to 3.5-fold increase throughout gestation in first-phase (p = 0.001) and second-phase (p = 0.0001) insulin release during the intravenous glucose tolerance test. Peripheral insulin sensitivity was estimated as the glucose infusion rate (in milligrams per kilogram fat-free mass per minute) during the hyperinsulinemic-euglycemic clamp. There was a significant (p = 0.0003) 56% decrease in insulin sensitivity through 36 weeks' gestation. These results are the first to prospectively evaluate the longitudinal changes in maternal carbohydrate metabolism from the time before conception through late gestation with newer methods such as the hyperinsulinemic-euglycemic clamp.

Administration, Oral↗
PubMed1991

Longitudinal changes in fat distribution in the Western Collaborative Group Study: a 23-year follow-up.

Anthropometric measurements for a total of 1,150 surviving subjects aged 65-86 and examined twice 23 years apart were analyzed with the following objectives: (1) to determine longitudinal changes on a large battery of anthropometric measures, (2) to examine the persistence of individual differences in the distribution of fat and relative weight, and (3) to investigate the relationship between changes in weight and changes in fat distribution. Significant changes toward an increase in size with age were observed in younger subjects below the age of 50 when first examined. In older subjects, age greater than or equal to 50, we observed a decrease in stature of 1.2 cm per decade, an overall decrease in weight of 1.6 kg, and no significant changes in trunk skinfold thickness. Longitudinal changes were most pronounced in the redistribution of fat and were also independent of weight changes. The relationships between measures of abdominal fat and overall obesity were stronger at follow-up than 23 years earlier.

Adipose Tissue↗
PubMed1994

Effect of grain exposure and smoking on the longitudinal changes in immediate skin reactivity.

The study was carried out to investigate the effect of occupational exposure and smoking on the longitudinal changes of immediate skin reactivity over 3 years in working populations. A total of 480 grain elevator workers and 707 transit and ferry (control) workers were included because they had allergy skin tests on both surveys. Skin-prick texts using three common allergens and a negative and histamine controls were administered during both surveys. The reaction was considered positive if the mean weal size was 3 mm or greater than that of the negative control. Conversion was defined as a change from the non-atopic state in the initial survey to the atopic state in the follow-up survey. Reversion was defined as a change from the atopic state in the initial survey to the non-atopic state in the follow-up survey. The findings showed that grain workers had two times risk of conversion than control workers. Recent smokers, who changed their habit from non-smoker/ex-smoker to smoker in the follow-up survey, were at a three times risk of conversion than non-smokers. The reversion of skin-test reactivity was not associated with age, smoking habits, or working exposure. When investigating studies of longitudinal changes in immediate skin reactivity, the effects of age, changes in smoking habit and occupational exposure should be considered.

Adult↗
PubMed1991

[Longitudinal change of H-1 spectroscopy in cerebral infarction].

Longitudinal change of the proton spectroscopy was observed in 2 cases of cerebral infarction. Proton spectra was acquired utilizing stimulated echo acquisition mode (STEAM). In acute stage, the increase of lactic acid and decrease of N-acetyl-aspartic acid (NAA) was observed prior to the appearance of abnormality in imagings such as magnetic resonance imaging and computer tomography. The increase of lactic acid was observed in subacute stage and chronic stage (in severe case). The decrease of NAA persisted in chronic stage. The increase of lactic acid and decrease of NAA indicate a damage of the ischemic tissue. The degree of the decrease of the NAA seems to be a reasonable indicator of the viability of the damaged tissue. The proton spectroscopy is a powerful modality for the evaluation of the extent of tissue damage caused by the ischemic insult.

Aged↗
PubMed1989

Longitudinal changes in distance-running performance of young males.

Longitudinal studies of adolescent males have shown that absolute maximal aerobic power (VO2max) and distance-running performance improve with age, while VO2max expressed relative to body mass remains stable. These earlier studies used subjects that were engaged in distance-run training; therefore, it was not possible to assess the relative importance of growth and/or run training to improved performance. The purpose of this study, therefore, was to quantify longitudinal changes in VO2max, running economy (RE), and distance-running performance in non-run-trained young males. Six subjects were tested at mean ages of 9.9 (T1) and 16.8 years (T2). Statistical tests of mean values revealed that over the 7-year period, relative VO2max remained unchanged (T1, 48.9 ml.kg-1.min-1; T2, 47.8 ml.kg-1.min-1) and RE improved (T1, 234.2; T2, 202.8 ml.kg-1.km-1), 9-min run distance increased (T1, 1637 m; T2, 2115 m), and the estimated percent of VO2max incurred during the 9-min run increased from 85.8% (T1) to 99.5% (T2). It was concluded that the improvement in distance-running performance observed in adolescent boys was not dependent upon run training. In view of the fact that maximal aerobic power remained stable, this change appears to be attributable to better running economy and an ability in runs of a fixed duration to perform at a higher relative work load.

Adolescent↗
PubMed1991

Cross-sectional age differences and longitudinal change on the Bradburn Affect Balance Scale.

Cross-sectional age differences and longitudinal change were examined on psychological well-being, positive affect, and negative affect, as measured by the Bradburn Affect Balance Scale. Data were collected from 1,159 participants in 1971 and 1985. Cross-sectional analyses showed age differences: older cohorts reported greater overall well-being but lower levels of both positive and negative affect when compared to younger respondents. Longitudinal analyses indicated small but significant changes toward decreased positive and negative affect but increased overall well-being. Negative affect had the strongest effect size. Positive and negative affect showed different patterns of change for different age groups. Taken together, cross-sectional and longitudinal findings suggest that change in affect variables is age-related, although these changes are relatively small. More evident was a pattern of correlational stability with age. Finally, the pattern of the results supports a two-factor theory of psychological well-being.

Adolescent↗
PubMed1994

Longitudinal changes in craniomandibular dysfunction in an elderly population in northern Sweden.

Longitudinal changes and cohort differences in craniomandibular dysfunction (CMD) were studied in a 79-year-old cohort (n = 65) and in 70-year-old cohorts in 1981 (n = 62) and 1990 (n = 60) by means of interview and clinical examination. Although the frequency of reported CMD symptoms decreased, many clinical signs of CMD increased during the 9-year observation period. Women reported more symptoms and showed more signs of CMD than men, and a great many of the clinical signs registered in 1981 still persisted in 1990. The 70-year-old cohort studied in 1990 showed a lower frequency of reported symptoms of CMD and of temporomandibular joint pain on palpation and a higher frequency of muscle pain and mandibular deviation than the 70-year-olds examined in 1981.

Age Factors↗
PubMed1989

[Longitudinal changes in the dentition of the deciduous reversed bite using plaster casts].

It is known that some of the deciduous reversed bite cases are corrected spontaneously by themselves. No decisive conclusion, however, has been achieved so far as to what morphological characteristics the self corrected cases have. The purpose of this study, therefore, was to determine whether the difference between the self corrected group (n) and the non-self corrected group (r) exists at their initial examination or if it occurs as a result of changes in occlusion. The materials used in this study were the serial plaster casts of 29 Japanese girls with the deciduous reversed bite at their first visit and these were measured with the three dimensional measurement system. The following results were obtained: 1. Characteristics of the initial examination with the n group: Overjet (-) and overbite in the n group were smaller than in the r group. The arch length and the perimeter of the maxillary dentition in the n group were longer, and the area of the incisive bone (U-C) was wider than in the r group. Moreover, the upper and lower canines in almost all of the n group cases were not touching each other and did not restrict mandibular movement, resulting in easy attrition for the deciduous anterior dentition. 2. Longitudinal changes in the n group: Mean change of this group showed a decrease in overbite caused by the attrition of the deciduous central incisors and the continuous eruption of the maxillary second deciduous molars. Overjet also decreased, because of an increase in the maxillary anterior arch length and of backward movement in the mandibular dental arch. Individual changes were much alike in mean changes in almost all of the measured items. Arch width between canines in the maxilla and arch length in the mandible decreased in some cases, suggesting that a discrepancy would occur when the permanent incisors erupt. 3. Longitudinal changes of the r group: Mean changes showed that overbite decreased in the same pattern as the n group, but overjet did not change and the mandible did not show backward movement. The reason was that overbite in this group was deeper than in the n group at the initial examination. Moreover, deciduous molar to molar width became wider to compensate the decrease in the arch length and the perimeter. Individual changes showed that some of the r group cases had a tendency to improve, but some became worse.

Female↗
PubMed1988

Longitudinal changes in blood viscosity are correlated with fetal outcome.

The importance of longitudinal changes in maternal Whole Blood Viscosity (WBV) for fetal well-being was investigated. Consecutive WBV data were available, obtained from 44 pregnancies before 36 0/7 weeks. An increase in WBV was found to be associated with an unfavorable fetal outcome. This result might be considered as clinical evidence supporting the hypothesis that maternal WBV contains information on the efficacy of placental perfusion.

Adult↗
PubMed1982

Longitudinal changes of serum lipid and apoB levels in a newborn-infant cohort.

Longitudinal changes in serum apoB levels in relation to serum lipid levels were determined in a subset (n = 30) of a newborn-infant cohort selected from infants (n = 440) of Bogalusa, Louisiana who were born between January 1, 1974 and June 30, 1975. Serum total cholesterol, triglycerides, beta + pre-beta-lipoprotein cholesterol and apoB levels were measured at birth, 6 mo, 1 yr, 2 yr, and 3 yr of age. The mean +/- SD, mg/dl, levels of these variables increased dramatically (p less than 0.0005) from birth to 6 mo (Total cholesterol: 65.0 +/- 15.7 versus 136.3 +/- 27.4; triglycerides: 32.9 +/- 18.9 versus 82.3 +/- 28.9; beta + pre-beta-lipoprotein cholesterol: 31.8 +/- 9.1 versus 87.3 +/- 25.7; apoB: 20.8 +/- 5.3 versus 49.0 +/- 13.5). On the other hand, the ratio of apoB to beta + pre-beta-lipoprotein cholesterol at birth was significantly higher than at 6 months of age (0.69 +/- 0.24 versus 0.58 +/- 0.12, p less than 0.0005). None of the variables changed significantly between 6 mo and 3 yr of age except the increase in serum total cholesterol level from yr 2 to yr 3 (142.6 +/- 26.6 versus 156.4 +/- 23,0, p less than 0.01). A high intra-child year to year correlation for serum apoB was noted beginning at 6 mo of age (r = 0.67, p less than 0.0001); while the apoB levels were proportional to beta + pre-beta-lipoprotein cholesterol levels in some children, others had varied levels of apoB in relation to cholesterol carried by this apoprotein. The fact that apoB levels persist beginning at 6 mo of age and that we are beginning to observe interindividual differences in levels of cholesterol carried by this apoprotein may have clinical implications for coronary artery disease.

Apolipoproteins↗
PubMed1989

Detection of longitudinal change in periodontitis.

In any longitudinal study of periodontitis, it is important to determine when change in probing depth or clinical attachment level occurs as soon as possible. In this study, simulation was used to compare three statistical methods for detecting change in linear periodontal measurement under a variety of conditions including type of change, number of follow-up visits, magnitude of linear measurement and examiner variance. The statistical methods included: 1) testing the slope of a regression line, 2) a comparison of running medians and 3) the cumulative sum (cusum) method. Three types of change and random examiner error were imposed on baseline linear measurements. The types of change included a gradual change, a burst, and rapid loss followed by regeneration. The results indicated that all three methods yielded similar results when the change was gradual. However, the regression line was less sensitive to bursts of change than the other methods. Overestimation of examiner error for the running median and cusum methods increased specificity and decreased sensitivity. Underestimation of examiner variance decreased specificity and increased sensitivity of the cusum and running median methods, while the regression was unaffected by estimates of examiner variance. If preventive or therapeutic action does not need to be taken immediately, either the running median or the cusum would be a good choice for detecting change. If immediate intervention is needed, the cusum appears to be the method of choice for detecting change at specific sites in longitudinal periodontal studies.

Follow-Up Studies↗
PubMed1994

[Longitudinal change in independence in the elderly--Kahoku Longitudinal Aging Study (KLAS)].

A community based study named Kahoku Longitudinal Aging Study (KLAS) was conducted since 1990 for the purpose of evaluating the comprehensive geriatric functional assessment (CGA) and preventing a decline in CGA in the community-dwelling elderly population. It was carried out in a Japanese rural town, in which 32% of the population was over 65 years of age. This study included a questionnaire about activity of daily living (ADL), information-related physical function, mental (cognitive and affective) and social functional domains. In addition to subjective informative instruments, various types of objective assessment such as quantitative neuro-behavioral function tests and medical examinations were performed. Subjects were all the eligible elderly aged over 65 years in the community. Although the ratio of subjects who were independent in ADL decreased with advancing age in both 1991 and 1993, the ratio of the independent elderly in ADL became significant higher (74%) in 1993 than in 1991 (71%). Scores on 2 kinds of neurobehavioral function tests in the 159 subjects aged over 75 years who attended the examination every year showed a significant and slight decrease during two years. However, some test indices significantly improved during the 2 years. These results suggested that age-related dependency in ADL and some kind of neurobehavioral functions might be prevented, in part, by health promoting education and improvement of life style.

Activities of Daily Living↗
PubMed1986

Longitudinal changes in forced expiratory volume in one second in adults. Methodologic considerations and findings in healthy nonsmokers.

Longitudinal changes in FEV1 (delta FEV1) have been examined in a sample of the general population of Tucson, Arizona. Adults with satisfactory spirometric tests in all 7 surveys performed over a period of 11 yr showed some between-survey differences in mean FEV1. Although small in absolute magnitude, such survey biases (which would be impossible to detect unless multiple spirometric tests were carried out on a relatively large group of subjects) could have a marked effect on calculated changes in FEV1 and may explain the widely divergent delta FEV1 values reported in the literature. After adjusting for survey biases, the relationships of delta FEV1 to age, sex, and body size were examined in "healthy" nonsmokers in the population who were followed for an average of 9.6 yr. The FEV1 showed an accelerating decline with age, and delta FEV1 was best explained by a model of proportional change in which it is a function of Age X Height3. Longitudinally determined delta FEV1 showed much less decline in function and a later apparent age of onset of decline than suggested by cross-sectional analyses. While small "learning effects" in longitudinal calculations cannot be excluded, most of the cross-sectional versus longitudinal differences are probably ascribable to past events that have adversely affected the FEV1 in older adults, thereby increasing cross-sectional age effects. Present findings also suggest that generally applicable "prediction equations" for delta FEV1 probably cannot be developed and that delta FEV1 values should only be compared between groups studied in an identical manner within a given study.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1987

Longitudinal changes in nutritional habits of teenagers: differences in intake between schooldays and weekend days.

Longitudinal changes in nutritional habits were studied in Dutch adolescents from 12 to 17 years of age (131 girls and 102 boys). The dietary differences on schooldays and weekend days are reported. In girls only small changes in nutritional habits were seen as they grew older. In boys there was a gradual increase in food intake with age. Overall, higher nutrient intakes could be seen on weekend days. The energy intake on weekend days was consistently higher for girls and boys in all age-groups. The proportional intakes of fat and sugar were rather high, especially on weekend days. The alcohol consumption increased with age for girls as well as boys, and was for some individuals extremely high (boys) on weekend days. The observed levels of intake compared with the recommendations showed a rather low intake of polyunsaturated fatty acids, polysaccharides and iron.

Adolescent↗
PubMedDate not supplied

Longitudinal changes in IQ among fragile X males: clinical evidence of more than one mutation?

Longitudinal changes in IQ among mentally retarded (MR) fragile X [fra(x)] males have been reported previously. While age is associated with decline in IQ, not all males are so affected. This suggests that there may be more than one subtype of affected fra(X) male. Therefore, we examined the distribution of standardized difference scores (Zdiff) in IQ to determine if subjects were from an admixture of at least 2 populations. Cluster analysis of Zdiff scores was used to partition subjects into 2 groups. Goodness-of-fit tests indicated that scores were more likely to come from an admixture. Discriminant functions (DF) were calculated to determine predictive validity of Zdiff scores. To eliminate the effect of skewing, a power transform was applied to Zdiff scores and DFs recomputed. Zdiff and transformed scores provided similar results. The mean and variance for one group showed no differences in test-retest scores as would be expected from examining any population while the mean for the second group indicated significant decline in IQ nearly 4 standard errors below the first test score. These results suggest that there may be clinical evidence for 2 types of fra(X) mutation: One which causes MR but is static, and a second mutation which causes MR but is dynamic and contributes to an apparent longitudinal decline in cognitive function.

Adolescent↗
PubMedDate not supplied

[Longitudinal changes in rigidity in old age].

This investigation attempted to deal with the question of longitudinal changes in the rigidity of attitudes and behaviour in a sample of elderly persons (68--90 years old). This was done by collecting data twice (1969/70 and 1976) from 86 subjects on a serie of measures of rigidity. At the same time additional data were collected on external variables such as intelligence, anxiety, state of health, extraversion, neuroticism, etc. Analyses of variance with the factors "time of measurement" and "sex" indicated a change in the predicted direction for the majority of the measures used. After an internal of six years, the capacity for adaptive and spontaneous flexibility had decreased, whereas intolerance and dispositional rigidity had increased. On the Riegel-scales R1 and R2, a rise in age was accompanied by a rise in rigidity, as measured in terms of statement in the form of personal judgments. Agreement with other judgments in the form of more generally formulated statements, on the other hand, decreased. Sex differences were found for Brengelmann's NR-scale and the Gottschaldt Hidden Figure test. Women were found to be less rigid than men, but also revealed less adaptive flexibility. A comparison of the test scores of longitudinal subjects and a comparable group of control group subjects yielded no signs of differences which would be traced back to a biased selection of the longitudinal sample.

Adaptation, Psychological↗