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PubMed1998

Risk factors for nuclear opalescence in a longitudinal study. LSC Group. Longitudinal Study of Cataract.

This study evaluated risk factors for increases in nuclear opacification of the lens in the Longitudinal Study of Cataract (1989-1993; Boston, Massachusetts), which included 764 participants. Baseline data on demographic, medical, and other risk factors were available from an earlier case-control study; follow-up visits were completed yearly over a 4-year period. The lens photographs taken at baseline and at each follow-up visit were graded using the Lens Opacities Classification System III protocol. Analyses evaluated which risk factors collected at baseline were related to increased nuclear opacification at follow-up. The MULCOX2 method, an extension of Cox regression for nested event-time data, was used to estimate the effects of the risk factors. This method accounted for the correlation between fellow eyes. Results showed that the risk of nuclear opacification increased with each year of age (relative risk (RR) = 1.07), white race (RR = 2.94), lower education (RR = 1.50), use of gout medications (RR = 2.32), current smoking (RR = 1.58), family history of cataract (RR = 1.39), and preexisting posterior subcapsular opacities (RR = 6.67). An association with early use of eyeglasses was also suggested (RR = 1.37). In conclusion, nuclear opacification was related to demographic and other variables, including potentially modifiable factors such as current smoking and use of gout medications. Most risk factors identified by this longitudinal study confirm those found by the original case-control study. The increased risk of nuclear opacities in whites appears to be a new finding.

Adult↗
PubMed2000

A fifteen-year longitudinal study in young adults on the relation of physical activity and fitness with the development of the bone mass: The Amsterdam Growth And Health Longitudinal Study.

Although positive effects of physical activity are often reported, there are still uncertainties about the type, intensity, duration, and frequency of these activities that are most effective for (re)modeling bone mass during youth. In the Amsterdam Growth and Health Longitudinal Study, daily physical activity and fitness were monitored from age 13 to 29 years in a group of 182 males and females. At a mean age of 28 years, bone mineral density (BMD) was measured at three sites with dual X-ray absorptiometry (DXA): in the lumbar region (lumbar BMD), the femoral neck (hip BMD), and the distal radius (wrist BMD). Physical activity (PA) was estimated from a cross-check activity interview taking in consideration all daily physical activities during the last 3 months; PA was scored in two different ways: (1) metabolic physical activity score (METPA) by weighting the intensity (multiples of basic metabolic rate [METs]) and duration (minutes per week); and (2) mechanic physical activity score (MECHPA) by weighting the peak strain (ground reaction forces as multiples of body mass) irrespective of frequency and duration of the physical activities. Physical fitness was measured with a neuromotor fitness test (composite of six strength, flexibility, and speed tests) and as cardiopulmonary fitness (maximal oxygen uptake). The physical activity and fitness scores were calculated over two age periods: during adolescence (13-16 years) and during adulthood (21-27 years). The standardized regression coefficients (corrected for gender, biological age, body composition, and calcium intake) show that weight, physical activity (both METPA and MECHPA), and neuromotor fitness during adolescence and in young adulthood are significantly and positively related with the lumbar BMD (beta = 0. 11-0.40) and hip BMD (beta = 0.18-0.26), measured at the mean age of 28 years. This was not the case for cardiorespiratory fitness. No significant correlations at all are found with wrist BMD, a bone site that is less involved in physical activity and fitness. It can be concluded that daily physical activity during adolescence and in the young adult period is significantly related to the BMD at the lumbar spine and femoral neck at age 28 of males and females. Only neuromotor fitness and not cardiopulmonary fitness during adolescence and young adulthood is related to the BMD of males and females at age 28 years.

Adolescent↗
PubMed2002

Can longitudinal changes in processing speed explain longitudinal age changes in fluid intelligence?

The processing-speed theory of cognitive aging contends tha age-related declines in intellectual function reflect the consequences of age-related slowing of processing speed. Cross-sectional data support this assumption. The association between 4-year changes in processing speed and 4-year changes in fluid intelligence was examined with a sample of 417 older adults. Changes in processing speed correlated .53 with changes in fluid intelligence. The difference in the explanatory power of processing speed regarding age-related differences and age-related changes is discussed with reference to other longitudinal studies and methodological considerations.

Aged↗
PubMed2006

Longitudinal trajectories in Guilford-Zimmerman temperament survey data: results from the Baltimore longitudinal study of aging.

We examined developmental trends in personality traits over a 42-year time period by using data from the Baltimore Longitudinal Study on Aging (N = 2,359; individuals aged 17-98), collected from 1958 to 2002. Hierarchical linear modeling analyses revealed cumulative mean-level changes averaging about 0.5 SD across adulthood. Scales related to extraversion showed distinct developmental patterns: General Activity declined from age 60 to 90; Restraint increased; Ascendance peaked around age 60; and Sociability declined slightly. Scales related to neuroticism showed curvilinear declines up to age 70 and increases thereafter. Scales related to agreeableness and openness changed little; Masculinity declined linearly. We found significant individual variability in change. Although intercepts differed, trajectories were similar for men and women. Attrition and death had no effect on slopes. This study highlights the use of lower order traits in providing a more nuanced picture of developmental change.

Adult↗
PubMed1998

Longitudinal changes in adaptive behavior in adults with Down syndrome: interim findings from a longitudinal study.

Age-related changes in adaptive behavior have been established in adults with Down syndrome. However, most studies have been cross-sectional, without controls for cohort and survival effects. We examined underlying factors for age-related decline in adaptive behavior in 128 adults with trisomy 21 over a 3-year period. Presence of dementia was the only determining factor, although the difference in trend over time as compared to subjects without dementia was not significant. No association between gender, sensory loss, severity of mental retardation, or place of residence was found. For subjects with no significant medical disorder (physical or psychological), no decline was seen. This longitudinal study confirms previously reported findings.

Activities of Daily Living↗
PubMed1993

A cross-study contextual analysis of effects from individual-level drinking and group-level drinking factors: a meta-analysis of multiple longitudinal studies from the collaborative alcohol-related longitudinal project.

In contextual (cross-level) analysis within multiple longitudinal general population studies, individual-level drinking behaviors (quantity per typical occasion, frequency of drinking per month and total volume of drinks per month) at final measurement are assessed by three models that simultaneously enter individual- and group-level measures. Two age groups (15-20 and 21-30) are independently assessed. In each model, the Time 1 individual-level drinking behavior and one of three group-level factors are entered. The group-level factors are (1) the percentage of abstainers at Time 1 for each age/sex cohort, (2) the Time 1 group mean for the drinking measure for the age/sex cohort and (3) the mean difference of the age/sex cohort's change in the drinking measure over time. All variables in the model are controlled by variations to exposure in per capita consumption of alcohol during the age/sex cohort's formative years and at Time 2. Meta-analysis assesses the homogeneity of the findings across studies. Models were proposed with the rationale that (1) understanding of individual drinking behavior can be advanced if individual-level data and group-level data are considered in the same models, and (2) integration of these two levels of analyses are, to date, rare. The rationale for using meta-analysis is that findings from the models can be assessed across social contexts with respect to their generalizability. The mean difference model, controlling for individual drinking at Time 1, is the most influential of the group-level models for the younger age group: the degree to which the group changes its drinking pattern is positively related to individual-level drinking behavior at final measurement, over and above the individual's drinking behavior at Time 1, for individual-level frequency of drinking among males (homogeneous among drinkers only). Younger females show more significant relationships for the mean difference females show more significant relationships for the mean difference model. Findings are significant for all relationships examined for the mean difference of the drinking of the group and the individual drinking among the older males and females. Measures of individual-level drinking for all measures at Time 1, controlling for the group-level effects, are significantly related to individual-level drinking at final measurement. The results are homogeneous for quantity (drinkers only) and volume among the young. Findings indicate that characterizations of the drinking for both the individual and the group to which the individual belongs predict measures of drinking practices on the individual level over time.

Adolescent↗
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↗
PubMed2005

Longitudinal validity of spirometers--a challenge in longitudinal studies.

QUESTION UNDER STUDY: Pulmonary function testing (PFT) in longitudinal studies involves the repeated use of spirometers over long time periods. We assess the comparability of PFT results taken under biologic field conditions using thirteen certified devices of various technology and age. Comparability of measurements across devices and over time is relevant both in clinical and epidemiological research. METHODS: Forced Vital Capacity (FVC), Forced Expiratory Volume in the first second (FEV1) and Forced Expiratory Flow 50% (FEF50) were compared before and after the data collection of the Swiss Study on Air Pollution and Lung Diseases in Adults (SAPALDIA) and the European Community Respiratory Health Survey (ECRHS) cohort studies. Three test series were conducted with 46, 50 and 56 volunteers using various combinations of spirometers to compare the eight flow-sensing spirometers (Sensormedics 2200) used in the SAPALDIA cross-sectional and follow-up, two new flow-sensing instruments (Sensormedics Vmax) and three volume displacement spirometers (two Biomedin/Baires and one Sensormedics 2400). RESULTS: The initial comparison (1999/2000) of eight Sensormedics 2200 and the follow-up comparison (2003) of the same devices revealed a maximal variation of up to 2.6% for FVC, 2.4% for FEV1 and 2.8% for FEF50 across devices with no indication of systematic differences between spirometers. Results were also reproducible between Biomedin, Sensormedics 2200 and 2400. The new generation of Sensormedics (Vmax) gave systematically lower results. CONCLUSIONS: The study demonstrates the need to conduct spirometer comparison tests with humans. For follow-up studies we strongly recommend the use of the same spirometers.

Adolescent↗
PubMed1989

Longitudinal health record: a pediatrician's viewpoint of the longitudinal health record.

This paper will discuss the Health Record in terms of content, value of a Longitudinal Record, need for a dynamic and interactive record versus the current archived chronological repository of information, areas of application in research, clinical benefits and population related research concerning present and future influences upon a person's health. It will contain the categories of information utilized in a model Health Record, what facts should be contained within a brief Synopsis or Record Abstract and the contents of a master Pediatric Database. Areas of uses, abuses, potential problems, security needs, privacy and confidentiality issues, legal aspects, transfer of information, technical considerations, computerization of the Record and other matters will be discussed.

Adolescent↗
PubMed1999

Siblings, parents, and partners: family relationships within a longitudinal community study. ALSPAC study team. Avon Longitudinal Study of Pregnancy and Childhood.

Links between sibling relationships, mother-partner, and parent-child relationships were studied in a longitudinal community sample of 3681 sibling pairs. Individual differences in sibling relationship quality were related to mother-partner affection and hostility assessed 4 years earlier, to contemporary parent-child negativity, and to indices of social adversity. Evidence for both direct and indirect pathways (via parent-child relations) linking mother-partner and sibling relations were found. Comparisons of prediction for non-stepfamilies and stepfather families showed similarities in patterns of association, but also differences: In stepfather families, mother-partner hostility was unrelated to parent-child negativity and sibling relationship quality. Both positivity and negativity towards young siblings decreased with the age of older siblings, and older sisters were more positive than older brothers.

Adult↗
PubMed2005

Predicting adolescents' longitudinal risk for sexually transmitted infection: results from the National Longitudinal Study of Adolescent Health.

BACKGROUND: Influencing adolescents' sexual behaviors has the potential to influence trajectories of risk for sexually transmitted infections (STIs) among young adults. OBJECTIVE: To determine whether family, school, and individual factors associated with increased duration of virginity also protect against STIs in young adulthood. DESIGN: Prospective cohort study. Wave I of the National Longitudinal Study of Adolescent Health occurred in 1995 when participants were in grades 7 through 12. Six years later, all wave I participants who could be located were invited to participate in wave III and provide a urine specimen for STI testing. SETTING: In-home interviews in the continental United States, Alaska, and Hawaii. PARTICIPANTS: Population-based sample. Of 18,924 participants in the nationally representative weighted wave I sample, 14,322 (75.7%) were located and participated in wave III. Test results for Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis were available for 11,594 (81.0%) of wave III participants. MAIN OUTCOME MEASURE: Positive test result for C. trachomatis, N. gonorrhoeae, or T. vaginalis. RESULTS: Controlling for biological sex, age, race/ethnicity, family structure, and maternal education, adolescents who perceived that their parents more strongly disapproved of their having sex during adolescence were less likely to have STIs 6 years later (adjusted odds ratio, 0.89; 95% confidence interval, 0.81-0.99). Those with a higher grade point average during adolescence were also less likely to acquire STIs (adjusted odds ratio, 0.84; 95% confidence interval, 0.71-0.99). Stratified analyses confirmed these findings among female, but not male, adolescents. Feelings of connection to family or school, reported importance of religion, attending a parochial school, and pledges of virginity during adolescence did not predict STI status 6 years later. CONCLUSIONS: Perceived parental disapproval of sexual intercourse and higher grades in school during adolescence have protective influences on the trajectory of risk for acquiring STIs, primarily among female adolescents. Most factors associated with increased duration of virginity in adolescence do not influence the trajectory of STI risk.

Adolescent↗
PubMed2004

The longitudinal relation between chronic diseases and depression in older persons in the community: the Longitudinal Aging Study Amsterdam.

OBJECTIVE: The purposes of this study were to examine the differences in influence of various chronic diseases on depressive symptomatology over time and to determine whether there were differences in such influence depending on physical limitations and time of onset of disease. STUDY DESIGN AND SETTING: Data for this study were obtained from the Longitudinal Aging Study Amsterdam. Two thousand two hundred eighty-eight respondents (age 55-85) were included and followed for a maximum of 6 years. Depressive symptoms (using the CES-D scale), the presence of seven frequently occurring chronic diseases, physical limitations, and sociodemographic variables were assessed by structured interviews. Generalized estimating equation models were estimated for each disease and compared with each other. RESULTS: Lung disease, arthritis, cardiac disease, and cancer were all positively associated with increased depressive symptoms over time. Stroke was associated with depressive symptoms, but these associations were not found when adjusted for physical limitations. For atherosclerosis and diabetes mellitus only weak or no associations with depressive symptoms were found. Recent onset of disease resulted in less strong associations for in cancer, lung disease, and arthritis. CONCLUSION: The results demonstrate that the level of depressive symptoms varies across type of chronic disease. In cardiac disease, arthritis, cancer, and lung disease increased depressive symptoms could not be attributed to physical limitations, but in stroke the association found with depressive symptoms was to a large extent attributable to physical limitations.

Age Factors↗
PubMed2000

Anastomotic longitudinal stress due to modification of arterial longitudinal properties after anastomosis.

BACKGROUND: In our hands, in vivo segmental vessel length changes up to 5% because of blood pressure: increasing in arterial pressure is associated to decrease in segmental vessel length. METHODS AND MATERIAL: Using two piezoelectric crystals sutured on vessel wall and a high fidelity pressure probe, we recorded artery length variations as function of blood pressure, before and after an end-to-end anastomosis on four pigs carotid arteries. RESULTS: Mean arterial pressure before anastomosis = 73 mmHg (+/- 12); mean arterial pressure after anastomosis = 91 mmHg (+/- 14); mean crystals displacement before anastomosis during systole = -0.21 mm; mean crystals displacement after anastomosis during systole = +0.24 mm; mean distance between crystals before anastomosis = 12.3 mm (+/- 0.8) and after anastomosis = 11.2 mm (+/- 0.5). CONCLUSIONS: In the acute phase following an end-to-end anastomosis, an increase in blood pressure causes increasing in vessel length, with an exponential correlation. The anastomosis is constantly subjected to a longitudinal traction whose magnitude depends on blood pressure.

Anastomosis, Surgical↗
PubMedDate not supplied

[Comparative characteristics of the gas-exchange parameters during exposure to lateral (Gy), longitudinal (Gz) and latero-longitudinal (Gz/Gy) G-loads].

Subject of the investigation was dynamics of gas-exchange parameters during exposure to lateral and laterolongitudinal g-loads (Gy, Gz, Gz/Gy) in a coach inclined at 300 from the horizontal with a rigid restraint system. Gy values varied between 0.5 and 5.0 units, Gz - between 3.0 and 9.9 units and Gz/Gy - between 2.6/1.8 and 5.0/3.0 units. In all instances, growth gradient of the radial loads was 1.0 u/s, and a period of exposure was up to 30 s. Comparison of the Gz vs. Gy tolerance revealed as a substantial increase of the physiological "cost", so a more visible disbalance of the diffusion/perfusion ratio of the lung. This is consistent with the gas-exchange data according to which lateral g-loads are a stronger stress-factor and more challenging for pilots than the longitudinal g-loads.

Aerospace Medicine↗
PubMed2000

Parkinson's disease and parkinsonism in a longitudinal study: two-fold higher incidence in men. ILSA Working Group. Italian Longitudinal Study on Aging.

OBJECTIVE: To determine the incidence of parkinsonism and PD in the Italian elderly, and to explore the relation with age and gender. METHODS: In eight Italian municipalities, a population-based, parkinsonism-free cohort was followed for an average of 3 years. At the end of the follow-up, the cohort survivors were directly contacted (screening and clinical examination). Cohort members who had died were studied using death certificates, clinical records, and information gathered from relatives and general practitioners. Parkinsonism diagnosis and subtyping were made according to specified diagnostic criteria. RESULTS: The cohort consisted of 4,341 individuals (65 to 84 years of age): 596 died before the examination, 2,863 (76.4% of the survivors) completed the screening procedure, and 882 refused to participate. The authors found 68 incident cases of parkinsonism: 42 PD (62%), 7 drug-induced parkinsonism (10%), 8 parkinsonism in dementia (12%), 8 vascular parkinsonism (12%), and 3 parkinsonism, unspecified (5.8%). Average annual incidence rate (per 100,000 person-years) in the population aged 65 to 84 years, adjusted to the 1992 Italian population, was 529.7 (95% CI, 400.5 to 658.9) for parkinsonism, and 326.3 (95% CI, 224.1 to 427.5) for PD. Incidence rates for both parkinsonism and PD increased with age in both men and women; men had higher rates in every age group. Age-adjusted relative risk in men compared with women was 1.66 (95% CI, 1.02 to 2.70) for parkinsonism and 2.13 (95% CI, 1.11 to 4.11) for PD. CONCLUSIONS: Incidence of parkinsonism and PD increased with age, PD was the most common type of parkinsonism, and men had a risk of developing PD twice that of women.

Aged↗