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PubMed2003

Longitudinal magnetic resonance imaging studies of older adults: a shrinking brain.

Age-related loss of brain tissue has been inferred from cross-sectional neuroimaging studies, but direct measurements of gray and white matter changes from longitudinal studies are lacking. We quantified longitudinal magnetic resonance imaging (MRI) scans of 92 nondemented older adults (age 59-85 years at baseline) in the Baltimore Longitudinal Study of Aging to determine the rates and regional distribution of gray and white matter tissue loss in older adults. Using images from baseline, 2 year, and 4 year follow-up, we found significant age changes in gray (p < 0.001) and white (p < 0.001) volumes even in a subgroup of 24 very healthy elderly. Annual rates of tissue loss were 5.4 +/- 0.3, 2.4 +/- 0.4, and 3.1 +/- 0.4 cm3 per year for total brain, gray, and white volumes, respectively, and ventricles increased by 1.4 +/- 0.1 cm3 per year (3.7, 1.3, 2.4, and 1.2 cm3, respectively, in very healthy). Frontal and parietal, compared with temporal and occipital, lobar regions showed greater decline. Gray matter loss was most pronounced for orbital and inferior frontal, cingulate, insular, inferior parietal, and to a lesser extent mesial temporal regions, whereas white matter changes were widespread. In this first study of gray and white matter volume changes, we demonstrate significant longitudinal tissue loss for both gray and white matter even in very healthy older adults. These data provide essential information on the rate and regional pattern of age-associated changes against which pathology can be evaluated and suggest slower rates of brain atrophy in individuals who remain medically and cognitively healthy.

Age Factors↗
PubMed1984

Health-related behavior of adolescents: change over time.

A longitudinal study of the changes in health-related behavior in Israeli adolescents was undertaken in a large, comprehensive secondary school. The incidence of starting to smoke and its relationship to the development of sexual behavior was assessed. Smoking, use of drugs, sexual behavior, and drinking of alcoholic beverages at the age of 16 years was related to dropout from secondary school during the 2-year study period. The possibility of developing a model of adolescent risk behavior and its relevance to planning of health and educational services is discussed.

Adolescent↗
PubMed2005

Mood changes related to antidepressants: a longitudinal study of patients with bipolar disorder in a naturalistic setting.

This prospective, longitudinal study investigated the frequency and pattern of mood changes between outpatients receiving usual care for bipolar disorder who were either taking or not taking antidepressants. Eighty patients with bipolar disorder self-reported mood and psychiatric medications daily for 3 months using a computerized system (ChronoRecord) and returned 8662 days of data. Of the total group of 80 patients, 47 took antidepressants; 33 did not. Patients taking antidepressants reported depression twice as frequently (29% of days vs. 13.8% of days). In both groups, two-thirds of all mood changes over a 1-, 2- and 3-day period were small, between -5 and 5 on a 100-point scale. No statistically significant difference was found in the frequency of large mood changes (>10 on a 100-point scale) or in switches between depression and mania (0.7% if not taking antidepressants vs. 0.9% if taking), independent of diagnosis of bipolar I or II. Eighty-nine percent of patients taking antidepressants were also taking mood stabilizers. In this naturalistic setting, no significant difference between the rate of switches to mania or rapid cycling was found between those taking and not taking antidepressants, regardless of diagnosis. The primary difference in pattern between the groups was the time spent in depressed or normal mood, with minor daily mood variations.

Adult↗
PubMed1994

Risk factor change in older persons, a perspective from Hong Kong: weight change and mortality.

BACKGROUND: The influence of anthropometric measurements on mortality and longevity has been of interest to a number of investigators. However, although such measurements are not stable over time, few studies have attempted to account for such changes in longitudinal studies. The present study attempts to examine the relationship between weight change and mortality outcome. METHODS: The research was based on a longitudinal study of a cohort of 1,056 Hong Kong Chinese men and women aged 70 and above. Among the 476 nonsmoking women at baseline, 374 with weight measurements both at baseline and at 24 months follow-up were included in the study. Proportional hazards analysis with adjustments for age and other physical and social factors was used to estimate the relative risk of mortality of the higher body mass index groups in relation to the lowest body mass index group and between the weight change groups. RESULTS: Women belonging to the middle tertile of body mass index distribution had the lowest mortality. Those with a weight loss of more than 2 kg over the first 24 months follow-up had five times the risk of mortality at 40 months, even after adjusting for health and social conditions and baseline body mass index. CONCLUSION: The results suggest that both the initial body weight and weight change during the follow-up period are important considerations in the study of the association between body weight and mortality.

Aged↗
PubMed2004

Clozapine-induced QEEG changes correlate with clinical response in schizophrenic patients: a prospective, longitudinal study.

BACKGROUND: The changes of theta activity (3.5-7 Hz) in the quantitative electroencephalography (QEEG) and serum clozapine levels and their correlation with clinical response, measured by the Positive and Negative Syndrome Rating Scale (PANSS) for schizophrenia, were examined prospectively in 16 patients suffering from schizophrenia during 18 weeks of clozapine (CLO) treatment. METHODS: Evaluations were performed on five occasions: before the initiation of CLO treatment at baseline and after 1, 3, 10, and 18 weeks of treatment. Doses of CLO starting from 50 mg/day were determined on the basis of clinical response. In the PANSS subscales for positive and negative symptoms, a significant (P < 0.05) improvement was observed after the first week, and in the subscale for general symptoms, improvement was seen after three weeks of treatment with CLO. A significant increase in theta power (P < 0.01) was found after three weeks of CLO treatment in the electrodes over the fronto-central scalp area, most distinctly in the midline. RESULTS: After three weeks we observed significant inverse correlations between the theta power increase and the changes in PANSS subscales for negative (P < 0.01) and positive (P < 0.05) symptoms, and after 10 weeks, between the theta power increase and the change in PANSS subscales for general (P < 0.05) and positive (P < 0.05) symptoms. After 18 weeks a trend of inverse correlation between the PANSS subscales for general and negative symptoms and the right and midline theta power increase was observed, but not with regard to positive symptoms. There were trends, but no significant correlations, between CLO treatment response and serum CLO levels. CONCLUSIONS: These findings indicate that the change in the theta frequency in QEEG and particularly in the midline electrodes over the fronto-central scalp area might be a more sensitive indicator for the evaluation of CLO treatment adequacy than the serum CLO level.

Adult↗
PubMed1996

The validity of a short food frequency questionnaire and its ability to measure changes in food intake: a longitudinal study.

BACKGROUND: In studies of health behaviour exploring factors associated with differences and changes in eating patterns of populations, diet is often measured with short food frequency questionnaires (FFQ). This study examines the validity of a short FFQ by comparing frequencies of food intake from the FFQ to information on food intake obtained by a diet history interview. METHODS: Food intake was measured at two separate occasions in the same 329 individuals, first in 1987-1988 and 6 years later in 1993-1994. RESULTS: In 1987-1988 the Spearman correlation coefficients were around r = 0.50 for most foods, with white and dark ryebread and light bread as extremes on the one hand (r = 0.10, r = 0.23 and r = 0.27, respectively) and coarse bread, fruit and cakes as extremes on the other (r = 0.61, r = 0.60, r = 0.60, respectively). In general, the correlations were higher at the second data collection in 1993-1994. At both data collections, the mean food intake from the diet history interview increased with increasing frequency category, indicating that the questionnaire was able to identify levels of food intake correctly. In general, when individual changes in food intake were assessed during the study period, those who reported a less frequent intake by the FFQ in 1993-1994 compared with 1987-1988 also had a lower mean daily intake according to the diet history information. CONCLUSION: The short FFQ can quantify food intakes and, is also responsive to changes in food intake over time. Thus the short FFQ can be used to monitor changes in food patterns at a group level.

Adult↗
PubMed2002

Personality change over 40 years of adulthood: hierarchical linear modeling analyses of two longitudinal samples.

Normative personality change over 40 years was shown in 2 longitudinal cohorts with hierarchical linear modeling of California Psychological Inventory data obtained at multiple times between ages 21-75. Although themes of change and the paucity of differences attributable to gender and cohort largely supported findings of multiethnic cross-sectional samples, the authors also found much quadratic change and much individual variability. The form of quadratic change supported predictions about the influence of period of life and social climate as factors in change over the adult years: Scores on Dominance and Independence peaked in the middle age of both cohorts, and scores on Responsibility were lowest during peak years of the culture of individualism. The idea that personality change is most pronounced before age 30 and then reaches a plateau received no support.

Adolescent↗
PubMed1993

Genetic change and continuity from fourteen to twenty months: the MacArthur Longitudinal Twin Study.

Genetic change as well as continuity was investigated within the domains of temperament, emotion, and cognition/language for 200 pairs of twins assessed at 14 and 20 months of age in the laboratory and home. The second year of life is marked by change rather than continuity: correlations from 14 to 20 months averaged about .30 for observational measures of temperament and emotion, about .40 for language measures, and about .50 for mental development. 2 types of genetic change were examined: changes in the magnitude of genetic influence (heritability) and genetic contributions to change from 14 to 20 months. In general, heritability estimates were similar at 14 and 20 months. Evidence for genetic influence on change from 14 to 20 months emerged for several measures, implying that heritability cannot be equated with stability. Analyses of continuity indicated that genetic factors are largely responsible for continuity from 14 to 20 months.

Child Development↗
PubMed2005

Continuity and change in preschool ADHD symptoms: longitudinal genetic analysis with contrast effects.

The genetic and environmental mediation of continuity and change in parent-reported ADHD symptoms were investigated in a cohort of over 6000 twin pairs at 2, 3 and 4 years of age. Genetic analyses of the cross-sectional data yielded heritability estimates of 0.78-0.81 at each age, with contrast effects. A common pathway model provided the best fit to the longitudinal data, indicating that genetic influences underlie 91% of the stable variance in ADHD symptomatology. In other words, what is stable for ADHD symptoms is largely genetic. Contrast effects acting in the same direction at different ages contributed to the observed continuity:longitudinal correlations were greater for dizygotic than monozygotic twins.

Attention Deficit Disorder with Hyperactivity↗
PubMed1994

Progressive loss of bone in the femoral neck in elderly people: longitudinal findings from the Dubbo osteoporosis epidemiology study.

OBJECTIVES: To determine prospectively the rates of change in bone mineral density in elderly people and to examine the relation between lifestyle and demographic factors and these rates of change. DESIGN: Longitudinal population based study. SETTING: Dubbo, New South Wales, Australia. SUBJECTS: Representative sample (n = 769) of residents aged > or = 60 on 1 January 1989. MAIN OUTCOME MEASURE: Rates of change in bone mineral density measured prospectively (mean scan interval 2.5 years) at the femoral neck and lumbar spine by dual energy x ray absorptiometry. RESULTS: Summary rates of loss in the femoral neck were 0.96% per year (95% confidence interval 0.64% to 1.28%) in women and 0.82% per year (0.52% to 1.12%) in men. Importantly, rates of loss at the femoral neck (both percentage and absolute) increased in both sexes with advancing age. No significant loss was evident in either sex at the lumbar spine, probably because of coexistent osteoarthritis. Lifestyle factors had only modest effects on rates of loss at either site. CONCLUSIONS: These data show that bone density of the femoral neck declines at an increasing rate in elderly people, and as this site is predictive of fracture suggest that treatment to minimise bone loss may be important even in very elderly people.

Absorptiometry, Photon↗
PubMed1987

A longitudinal study of anteroposterior growth changes in the palatine rugae.

Palatine rugae have been used as internal dental cast reference points for quantification of tooth migration. Some, but not all, investigators have reported the medial rugal region to be stable or to show predictable change. The purpose of this study was to use the longitudinal data base of the Child Research Council of Denver to examine the anteroposterior stability of the medial rugal region. Dental casts of 20 females and 21 males with untreated normal Angle Class I occlusions were selected. Time intervals measured were: T1--primary teeth erupted, T2--earliest cast with permanent first molars erupted, T3--earliest cast with canines and pre-molars erupted, and T4--ages 16 to 22. Distinctive left and right anterior and posterior rugae which appeared on all four casts were identified, the medial ends marked, and the anteroposterior distances measured. The data were evaluated with the paired t test, repeated-measures ANOVA, and Tukey's multiple comparison procedure. From T1--T4, the medial rugal region increased 1.4 +/- 0.6 mm in females and 2.3 +/- 0.8 mm in males. Only two cases showed a trend toward stability. There were no significant differences by side. Significant increases in size occurred between T2 and T3 for females and males and between T3 and T4 for males. Analysis of these data indicates that the medial rugal region increases significantly in anteroposterior length, but not uniformly between the sexes across observation times. Such changes are characteristic of general craniofacial growth and suggest that the rugal region is responding to the differential growth of the underlying bone. Therefore, medial rugal landmarks appear not to be stable reference points for tooth migration research.

Adolescent↗
PubMed1994

Longitudinal research on adolescent voice change in males.

Many of the characteristics and processes associated with adolescence are reasonably well understood; others are not. Still unanswered are questions about adolescent voice change. For example, when does the average child start the process; what changes result and what is their extent; when is it complete? Further, how closely do shifts in vocal level parallel, or even predict, the adolescent process? This project was carried out in order to obtain data which would complement available information on the subject and provide additional specificity about voice change and pubescence--at least for boys. To that end, a longitudinal study was conducted in which 48 males were tracked over a 5-year period. Voice measurements were made--including speaking fundamental frequency (SFF) and phonational frequency range (PFR)--as were others relating to physical size (height, weight, and six body dimensions). It was found that (1) stable adolescent voice change (AVC) measurements could be obtained, (2) maturation patterns appeared predictable on the basis of AVC changes, and (3) both the onset and duration of voice change extended over a longer period of time than had been previously thought.

Adolescent↗
PubMed2003

Sex hormones and the changes in adolescent male lipids: longitudinal studies in a biracial cohort.

OBJECTIVE: To determine the role of increasing free testosterone and estradiol in pubertal changes in male lipids. METHODS: We conducted a 3-year, longitudinal, observation study with biannual visits of 251 black and 285 white boys who were 10 to 15 years of age at enrollment. Sex hormones, lipid parameters, and body composition measures were obtained according to a standard protocol. The body mass index (kg/m(2)) was used to characterize obesity. RESULTS: White boys had higher triglycerides, lower high-density lipoprotein cholesterol (HDL-C), lower apolipoprotein (apo)AI, and higher apoB than black boys. In boys of both races, increased body mass index was associated with increases in triglycerides, low-density lipoprotein cholesterol, apoB and decreases in HDL-C and apoAII. Within this framework, increased free testosterone was associated with increased apoB and decreased HDL-C and apoAI, whereas increased estradiol was associated with increased HDL-C and decreased triglycerides, low-density lipoprotein cholesterol, and apoB. CONCLUSION: Changes in sex steroid hormones have significant effects on changes in lipid parameters-increasing free testosterone levels has atherogenic effects and increasing estradiol has antiatherogenic effects.

Adolescent↗
PubMed1997

Cerebellar volume in adults with Down syndrome.

OBJECTIVES: To determine the effects of aging on cerebellar volume in individuals with Down syndrome (DS). To determine whether volume of cerebellum is associated with dementia or with age-related decline in fine-motor control. DESIGN: Case-control study involving comparison of cerebellar volumes in adults with DS and matched control subjects; survey study involving correlations between cerebellar volume and subjects' age and performance on a test of fine motor control; and longitudinal study assessing change in cerebellar volume in adults with DS. SETTING: The Johns Hopkins University School of Medicine, Baltimore, Md. PATIENTS AND OTHER PARTICIPANTS: Subjects included 40 adults with DS. Thirty of them were matched on age, sex, and race with cognitively normal subjects. A diagnosis of probable dementia was made for 5 of the subjects with DS. Longitudinal data were available for 23 of the 40 subjects with DS, with a mean interscan interval of 2 years. MAIN OUTCOME MEASURES: Volumes of cerebellum, total brain, and intracranial region were measured on magnetic resonance imaging scans. The Purdue Pegboard, a test of fine-motor control, was administered to 38 of the subjects with DS. RESULTS: Subjects with DS had significantly smaller cerebellar volumes than matched controls, even after adjusting for total brain volume or total intracranial volume. Volume of cerebellum did not correlate significantly with age for either the subjects with DS or controls. Longitudinal change in cerebellar volume in subjects with DS was not significant. Volume of total brain, but not cerebellum, correlated significantly with performance on the Purdue Pegboard. CONCLUSIONS: Although cerebellar volumes are disproportionately small in individuals with DS, they do not diminish significantly with age and do not undergo age-related atrophy that is different from that of normal controls. Volume reduction in the cerebellum does not appear to be specifically responsible for the age-related decline in fine-motor control that is observed in adults with DS.

Adult↗
PubMed2006

Changes in arch width. A 20-year longitudinal study of orthodontic treatment.

The changes in the dental arch dimensions that occur as a result of growth and treatment are of interest to the orthodontist and require careful consideration during treatment planning. A greater understanding of these changes could influence the patient's expectations from treatment as well as the formulation of the treatment and retention plans by the clinician. A retrospective study of the maxillary and mandibular canine and molar arch width changes in 60 patients over 20 years was carried out. Approximately half were treated orthodontically, and measurements were made on dental casts taken at four time points during the study: 1981, 1985, 1989, and 2001. Between baseline and final follow-up, the treated group demonstrated a statistically significant increase in maxillary intercanine arch width and statistically significant decreases in maxillary intermolar and mandibular intercanine and intermolar widths. No significant changes were observed for the untreated group. When comparing the orthodontically treated group with the untreated group, there was a significantly greater increase in maxillary intercanine width and a significantly greater reduction in mandibular intercanine width in the treated group over the duration of the study. No significant difference was observed between treated and untreated groups for maxillary and mandibular intermolar width changes. Sex had no statistically significant effect on these treatment differences. Type of orthodontic treatment had no effect on arch width changes within the treated group; however, the effect of tooth extraction needs further investigation.

Adolescent↗
PubMed1994

Longitudinal study on oral health in subjects with Alzheimer's disease.

OBJECTIVE: To examine longitudinal oral health changes in unmedicated, generally healthy subjects with Alzheimer's disease (AD) and compare them to age- and gender-matched healthy, unmedicated control subjects. DESIGN: Oral health parameters were evaluated over 2 to 3 years and the results compared between subjects with AD and controls. SETTING: Clinical Center of the National Institutes of Health, Bethesda, Maryland. PARTICIPANTS: Twenty-one community-dwelling subjects with a clinical diagnosis of AD and 21 age- and gender-matched control subjects. Neither population was being treated for any other systemic condition nor taking any prescription medications. MEASUREMENTS: Unstimulated and stimulated major salivary gland flow rates were measured, and gingival, periodontal, dental, and oral mucosal tissues assessed. MAIN RESULTS: In general, subjects with AD demonstrated decreased salivary flow rates and diminished oral health, but most longitudinal changes in oral health status were not significantly different than controls. CONCLUSIONS: Patients with AD are susceptible to a variety of oral health problems, and progression of AD can lead to a deterioration in oral health and function. These patients require aggressive preventive care to maintain function for as long as possible, which necessitates close cooperation among numerous health care professionals.

Aged↗
PubMed1998

Arch length changes from 6 weeks to 45 years.

The purpose of this study was to evaluate, on a longitudinal basis, changes in maxillary and mandibular arch length over a 45-year period. Subjects were drawn from two pools of normal individuals. Twenty-eight male and 33 female infants were evaluated longitudinally at 6 weeks, 1 year, and 2 years (before the eruption of the deciduous dentition). Fifteen males and 15 females from the Iowa Facial Growth Study were evaluated at 3, 5, 8, 13, 26, and 45 years. Arch length measurements were obtained independently by two investigators. Intra- and interexaminer reliabilities were predetermined at 0.25 and 0.5 mm, respectively. The greatest incremental increases occurred during the first two years of life. Arch length continued to increase until 13 years in the maxillary arch, and until 8 in the mandibular. Then significant and consistent decreases occurred in both arches mesial to the permanent first molars.

Adolescent↗
PubMed2005

Cross-sectional and longitudinal analyses of anatomical sulcal changes associated with aging.

Imaging studies of the human brain indicate that the cortex undergoes anatomic changes during the aging process. With the ability to study the human brain in vivo using magnetic resonance imaging, understanding the nature and location of these changes is of increasing interest. In this work, we investigate cross-sectional and longitudinal age effects on the geometric shape and gray matter (GM) volume for regions of interest on the cortical surface. Each of the regions corresponds to the buried cortex surrounding the sulcal spaces and is termed a "sulcal region." The study consists of 35 older adults scanned three times over a 4-year time span. The group includes 19 women and 16 men ranging in ages from 59 to 84 years (mean 70.9, standard deviation 6.2). We analyze 8 sulcal regions-the buried cortex surrounding the left and right central, superior frontal, cingulate, and parietooccipital sulci. We examine surface area, GM thickness, GM volume, sulcal depth, local gyrification index, and measures of curvature. Results indicate cross-sectional age effects in mean thickness, GM volume, sulcal depth, and curvature characteristics of sulcal regions. In addition, we found longitudinal decreases in surface area, mean thickness, GM volume, and sulcal depth measures as well as changes in sulcal curvature.

Aged↗