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PubMedDate not supplied

Can an improved environment cause maximum lifespan to decrease? Comments on lifespan criteria and longitudinal Gompertzian analysis.

Longitudinal Gompertzian analysis yields the counterintuitive conclusion that an improved environment can cause a decrease in maximum lifespan. The basis for this conclusion is examined. Results include the following: 1) The use of a specified high mortality rate as a criterion for maximum lifespan is arbitrary and leads to a calculated lifespan which is quite sensitive to the value of the criterion. 2) The definition of lifespan as the age to which a specified small population fraction survives is less arbitrary and less sensitive to the chosen criterion value. 3) However, the use of a survival criterion for lifespan in place of a mortality-rate criterion does not eliminate the seeming contradiction between environmental improvement and decreased lifespan. 4) Mortality rates can be approximated in semilogarithmic coordinates by three straight-line segments. The first segment, applicable through age 85, is the conventional Gompertz function. The second segment, representing ages 85 through 96, has a lower slope than the first, while the third segment, representing ages 96 through 124, has a negative slope. 5) The mortality rate obtained by extrapolating the first segment to a nominal age of maximum lifespan differs markedly from the true mortality rate at that age. 6) The conclusion that an improved environment is associated with a reduction in lifespan arises as a consequence of such an extrapolation.

Adult↗
PubMedDate not supplied

Longitudinal analysis of antibodies to histones, Sm-D peptides and ubiquitin in the serum of patients with systemic lupus erythematosus, rheumatoid arthritis and tuberculosis.

A longitudinal analysis of 12 lupus patients has been undertaken to assess their autoantibody reactivity by ELISA with histones, Sm-D peptides, ubiquitin and DNA. As controls patients with rheumatoid arthritis and tuberculosis were studied. Whereas the control groups showed little evidence of autoantibody reactivity 25% or more of the lupus patients had raised levels of autoantibodies against eight of the nine antigens tested. Of particular note was the fact that approximately 70% of the blood tested possessed antibodies reacting with Sm-D peptide 1-20. In contrast only one patient had anti-Sm antibodies by counter immunoelectrophoresis. In general the levels of antibodies to core histones reflected disease activity unlike the levels of anti-H1 antibodies. High levels of antibodies to ubiquitin often seemed to correlate inversely with active lupus and DNA antibody levels.

Adult↗
PubMed1996

Longitudinal analysis of abnormal involuntary movements in long-term clozapine-treated patients.

As part of a prospective efficacy and safety monitoring system, patients receiving clozapine are assessed monthly for dyskinetic events (DE), using the Abnormal involuntary Movement Scale (AIMS). Longitudinal analysis of 45 patients revealed 20 with baseline DE, 7 who developed emergent DE after a negative baseline assessment, and 18 patients with no DE symptoms throughout treatment with clozapine. Eight of the 20 patients with baseline DE were assessed to resolution of symptoms, with an average time of 261 +/- 188 days; 5 were evaluated until complete resolution of symptoms (AIMS = 0), with an average time of 691 +/- 462 days. The average time to onset of DE in emergent DE patients was 238 +/- 179 days, and the average time to resolution was 347 +/- 179 days after diagnosis. Four patients attained complete resolution with an average time of 629 +/- 293 days after diagnosis. It appears this emergent type of dyskinesia is different from other currently described dyskinesias. Overall, of the 27 patients having DE at any point in treatment, 15 of 27 (56%) had resolution of symptoms and 10 of 27 (37%) had complete resolution of DE. Clinicians should be aware of the utility of clozapine in dyskinesia and the extended time frame of response.

Adult↗
PubMedDate not supplied

A comparison of therapy continuation rates of different hormone replacement agents: a 9-month retrospective, longitudinal analysis of pharmacy claims among new users.

OBJECTIVE: To estimate the rate of therapy continuation among women using six different hormone replacement therapies (HRTs). DESIGN: A retrospective, longitudinal analysis of pharmacy claims data was conducted for 7,120 women who were new users of six HRT regimens. Continuation rates of therapies were examined at the end of the 9-month period. In addition, the odds ratio of continuation for each product was determined using a logistic model, which controlled for the potential influence of a patient's age and a provider's age, gender, specialty, and geographical location. RESULTS: Treatment continuation rates at the end of the 9-month period were significantly higher among patients prescribed oral 1 mg norethindrone acetate/5 microgram ethinyl estradiol (EE) (femhrt, Pfizer Inc, New York, NY, USA) compared with other HRT regimens. Patients prescribed 1 mg norethindrone acetate/5 microgram EE were 52% more likely to continue therapy compared with patients prescribed 0.625 mg conjugated equine estrogens/2.5 mg or 5 mg medroxyprogesterone acetate (Prempro, Wyeth, Madison, NJ, USA). Significantly higher rates of therapy continuation were seen in women aged 55 years or older, those who did not switch HRT during the analysis, those who received care in the central and northeast regions of the United States, and those who were seen by obstetricians/gynecologists (v primary care physicians) or female (v male) providers. CONCLUSIONS: The higher rates of treatment continuation seen with newer continuous combined HRTs, such as 1 mg norethindrone acetate/5 microgram EE, may lead to improved long-term compliance and, therefore, better protection against osteoporosis in postmenopausal women.

Adolescent↗
PubMed2003

Medicaid community-based programs: a longitudinal analysis of state variation in expenditures and utilization.

As states face challenges posed by budget crises and pressures to develop Medicaid home and community-based services (HCBS), this paper provides a longitudinal analysis of state variation in expenditures and utilization for three HCBS programs (waivers, home health and personal care), and for total Medicaid HCBS. The first part of the analysis describes the nature and scope of state variation for each program in 1999, using such measures as participants per 1,000 population and expenditures per capita. The second part of the analysis presents time-series regression models that estimate sociodemographic, state policy, and market factors associated with intra-state variation in waiver participants and expenditures, and home health, personal care and total HCBS expenditures for the period 1992-99. Among the results, positive state-level factors related to HCBS participants and expenditures include: higher percentages of aged people, greater incomes per capita, and a larger supply of home health agencies.

Aged↗
PubMed1999

Personal or environmental causes of happiness: a longitudinal analysis.

The author analyzed an integrative model of happiness, which incorporated personal factors (demographics, extraversion, neuroticism, and locus of control) and environmental factors (life events and social support), using a longitudinal data set. A secondary purpose was to clarify the relationship between overall happiness and life satisfaction. Using systematic random sampling, 581 residents of Kaohsiung, Taiwan, completed structured questionnaires at Time 1; among them, 105 returned valid questionnaires 2.5 years later, at Time 2. Longitudinal analysis indicated moderate stability of the subjective well-being (SWB) measures. More importantly, when both the baseline SWB levels and personality traits were statistically controlled, social support still predicted overall happiness, and positive life events predicted life satisfaction. Furthermore, there was a consistently strong bidirectional relationship between overall happiness and life satisfaction.

Adolescent↗
PubMed1997

Fetal heart rate (FHR) pathology in labor related to preceeding Doppler sonographic results of the umbilical artery and fetal aorta in appropriate and small for gestational age babies. A longitudinal analysis.

The aim of this study was to ascertain the value of serially performed Doppler sonographic measurements of fetal vessels for the prediction of FHR alterations in labor a longitudinal analysis was conducted. 24 patients with SGA fetuses as the only risk factor and 38 patients without any risk factor were recruited for the study. Flow velocity waveforms of the fetal aorta and the umbilical artery were analyzed for systolic diastolic (S/D) ratio weekly at 20-39 weeks gestation and from 30 weeks gestation onwards twice weekly. Courses were related to complications during labor reflected by alterations of FHR tracings. The more numerous pathologie S/D ratios of both fetal vessels were recorded the more frequently complications in labor occurred (Chi Square test, p < 0.05). The mean value of the S/D ratios in fetuses with FHR pathology in labor differed significantly compared to the uncomplicated group (Wilcoxon rank sum test, p < 0.05). The fluctuation of S/D ratios was greater in the complicated than in the normal group (Wilcoxon rank sum test, p < 0.05). A combination of parameters describing S/D ratios showed a sensitivity of 86% and a specificity of 19% for the fetal aorta and a sensitivity of 71% and a specificity of 91% for the umbilical artery. Serial Doppler measurements of the fetal aorta and the umbilical artery aid in predicting pathologic FHR alterations in labor and may be of benefit in antenatal care to ensure fetal well being particularly in cases of IUGR.

Aorta↗
PubMed2004

Working memory and aging: a cross-sectional and longitudinal analysis using a self-ordered pointing task.

Age-related declines in working memory performance have been associated with deficits in inhibition, strategy use, processing speed, and monitoring. In the current study, cross-sectional and longitudinal methodologies were used to investigate the relative contribution of these components to age-related changes in working memory. In Experiment 1, a sample of 140 younger and 140 older adults completed an abstract design version of the Self-Ordered Pointing Task modeled after Shimamura and Jurica (1994). Experiment 1 revealed that only processing speed and monitoring explained age differences in SOPT performance. Participants in Experiment 2 were 53 older adults who returned 4 years after the initial testing and 53 young adults. A task that assessed the ability to generate and monitor an internal series of responses as compared to an externally imposed series of responses was also administered. Experiment 2 replicated the key findings from Experiment 1 and provided some further evidence for age-related internal monitoring difficulties. Furthermore, the exploratory longitudinal analysis revealed that older age and lower intellectual abilities tended to be associated with poorer performance on the SOPT at Time 2.

Adolescent↗
PubMed2001

Effects of alcohol consumption on disability among the near elderly: a longitudinal analysis.

Data from four waves of the Health and Retirement Study are used to analyze the effects of alcohol use on disability, mortality, and income transfers from public programs. Cross-sectional analysis reveals a complex relationship, with a history of problem drinking clearly leading to higher rates of limitations, and a nonmonotonic relationship between current drinking and disability. In longitudinal analysis, problem drinking was predictive of disability onset, but not of transfer receipt or mortality. Heavy drinkers and problem drinkers, if anything, were less likely to receive public income support than abstainers or moderate drinkers. The likelihood that heavy drinkers received public transfers did not decrease relative to others following statutory changes in 1996 that sought to limit eligibility of alcoholics and drug abusers.

Age of Onset↗
PubMedDate not supplied

A longitudinal analysis of the efficacy of environmental interventions on asthma-related quality of life and symptoms among children in urban public housing.

In an environmental intervention study in public housing, we examined monthly Juniper Paediatric Asthma Quality of Life (QOL) Questionnaires for 51 children. Longitudinal analysis and spline models were used to identify time periods with significant improvements in QOL to inform judgments about causality. We found significant improvements in QOL, with moderate improvements before environmental interventions, increased rates of improvement immediately after, and reduced rates more than 5 months post-intervention. Effect modification analyses identified high-risk subpopulations and emphasized the importance of environmental, social, and economic conditions. Our results demonstrate the value of longitudinal techniques in evaluating the benefits of environmental interventions for asthma.

Adolescent↗
PubMed2000

[Acceptance of wearing hearing aids by children: a longitudinal analysis].

There exist no systematic longitudinal studies concerning the acceptance of hearing aids in Germany. This study examines the acceptance of a hearing aid (defined by its daily/weekly use) in the management of children with persistent sensorineural hearing loss over a period of years. 35 children with monaural or binaural hearing loss were treated with a hearing aid. All children had at least a 25-dB averaged mid-frequency pure-tone hearing loss (500, 1000, 2000, 4000 Hz). The data consist of standardized parent ratings at 4 points in time over a period of nearly 30 months. Unilateral-impaired children wore their hearing aids less often than bilateral-impaired children. This effect was not significant at the beginning (P = 0.85) but increased over time. By the end the difference was significant (P = 0.004). Mild to moderate monaural hearing-impaired children accepted their hearing aids, whereas children with severe to profound hearing loss refused to wear them. Bilateral hearing-impaired children demonstrated, a priori, a better wearing acceptance that even improved with time. There was never a significant difference between boys and girls in their average wearing time. A significant correlation of age and wearing acceptance was also not observed at any time. Hearing aids are an effective treatment with high acceptance and compliance, especially by children with bilateral sensorineural hearing loss. The quality of acceptance of monaural hearing-impaired children needs to be studied further.

Auditory Threshold↗
PubMed1992

Relationships among smoking status, body composition, energy intake, and physical activity in adult males: a longitudinal analysis.

This study evaluates the longitudinal relationships among smoking and adiposity, dietary intake, and physical activity in a group of adult males. Subjects were 101 nonsmokers and 19 regular cigarette smokers. Adiposity, dietary intake, and physical activity were assessed annually for three consecutive years. Results indicated that nonsmokers had larger tricep skinfold measurements than smokers over the 3-year period. However, dietary intake and physical activity did not differ between groups. Due to the absence of differences on these two variables for the smoking and nonsmoking groups, it was concluded that the lower adiposity in smokers was largely metabolically determined, which may make difficult the treatment of postcessation weight gain.

Adult↗
PubMed1993

Marital satisfaction, depression, and attributions: a longitudinal analysis.

This study examined the longitudinal relation between causal attributions and marital satisfaction and tested rival hypotheses that might account for any longitudinal association found between these variables. Data on attributions for negative partner behaviors, marital satisfaction, depression, and self-esteem were provided by 130 couples at 2 points separated by 12 months. To the extent that spouses made nonbenign attributions for negative partner behavior, their marital satisfaction was lower a year later. This finding was not due to depression, self-esteem, or initial level of marital satisfaction, and also emerged when persons reporting chronic individual or marital disorder were removed. Results support a possible causal relation between attributions and marital satisfaction.

Depression↗
PubMedDate not supplied

Perceived discrimination and the adjustment of African American youths: a five-year longitudinal analysis with contextual moderation effects.

Longitudinal links between perceived racial discrimination and later conduct problems and depressive symptoms were examined among 714 African American adolescents who were 10-12 years old at recruitment. Data were gathered 3 times over a 5-year period. Hypotheses were tested via latent curve modeling and multiple-group latent growth modeling. Increases in perceived discrimination were associated with increased conduct problems and depressive symptoms. This association was weaker when youths received nurturant-involved parenting, affiliated with prosocial friends, and performed well academically. For conduct problems, the association was stronger for boys than for girls; for depressive symptoms, no gender differences emerged. The findings thus identify contextual variables that moderate the contribution of perceived discrimination to African American youths' adjustment.

Achievement↗
PubMed1999

Doppler fetal circulation in pregnancies complicated by pre-eclampsia or delivery of a small for gestational age baby: 2. Longitudinal analysis.

OBJECTIVE: To observe the longitudinal changes in growth, and associated Doppler measurements, of the fetal circulation in pregnancies with a normal outcome and those complicated by pre-eclampsia, birth of a small for gestational age baby, or a combination of these complications. METHODS: Two hundred and ninety-two women had serial ultrasound scans performed from the 24th week of pregnancy. Measurements obtained included: the abdominal circumference, umbilical artery pulsatility index, the middle cerebral artery pulsatility index and time-averaged velocity, and the thoracic aorta pulsatility index and time-averaged velocity. Outcome measures included the birth of a small for gestational age infant, pre-eclampsia or a combination of these complications. RESULTS: One hundred and sixty-seven pregnancies ended in the normal birth of an appropriately grown infant at term, while 105 had a complicated outcome. They were divided into three categories: preeclampsia only (i.e. with the birth of an appropriately grown fetus, n = 13); small for gestational age only with no evidence of pre-eclampsia, n = 55; and pre-eclampsia complicated by the birth of a small for gestational age infant, n = 37. The group with pre-eclampsia complicated by small for gestational age was closest in characteristics to true clinical intrauterine growth restriction. A reduction in the abdominal circumference mirrored a rise in the umbilical artery pulsatility index and preceded changes in the middle cerebral artery and thoracic aorta. The greatest degree of change in the fetal circulation was observed during the three weeks preceding delivery. Ratios of the values obtained from the fetal and umbilical circulation demonstrated the greatest deviation from normal. CONCLUSIONS: A reduction in fetal growth velocity preceded changes observed in the fetal circulation. Ratios of the fetal Doppler parameters provided the clearest evidence of deterioration in the fetal condition. The information provided may be of use in the diagnosis and management of the growth-restricted fetus.

Female↗
PubMed1983

[Significance of longitudinal analysis for the evaluation of early detection studies in childhood].

In 1971, the first preventive examination programme for children up to 4 years of age was started in the Federal Republic of Germany; in 1977 followed a completely revised programme. However, even with this altered documentation a longitudinal analysis is not feasible. An effective evaluation should yield the following results: 1. Assessment of the success through differentiated recording of sufficiently early recognized health disorders and treatment effects. 2. Availability of reliable, regional and nation-wide statistics on incidence and prevalence. 3. An estimate of the number of health professionals required. - These aims can be achieved only by a longitudinal record linkage of the data on individuals of a sufficiently large random sample. For this purpose a revised data-sheet is presented. In addition, specific suggestions are made for longitudinal evaluations.

Child, Preschool↗
PubMed2006

The association between lower urinary tract symptoms and renal function in men: a cross-sectional and 5-year longitudinal analysis.

PURPOSE: We assessed the association between LUTS and renal function in men in a cross-sectional and a longitudinal study. MATERIALS AND METHODS: Men participating in health investigation in Vienna entered this study. In the cross-sectional analysis a consecutive series of men were studied and in the longitudinal analysis men were reevaluated after 5 years. LUTS were assessed by I-PSS and renal function was evaluated by GFR, as calculated by the Cockcroft-Gault equation. RESULTS: A total of 2.469 men with a mean age of 47.1 years (range 30 to 80) entered the cross-sectional study and 439 with a mean age of 51.7 years (range 45 to 79) could be assessed in longitudinal analysis. In the cross-sectional study there was no association between the degree of LUTS and GFR during 5 life decades (p = 0.55). An identical pattern was observed for irritative and obstructive scores. In the longitudinal cohort mean GFR +/- SD decreased from 84.3 +/- 20.2 ml per minute at baseline to 79.2 +/- 18.7 ml per minute after 5 years (-6.0%, p <0.0001). The mean decrease in GFR after 5 years was 4.5 ml per minute (-5.4%) in men without/mild LUTS (I-PSS 7 or less at ages 55.4 +/- 11.0 years), 3.9 ml per minute (-4.9%) in those with moderate LUTS (I-PSS 8 to 20 at ages 61.3 +/- 11.6 years) and 4.2 ml per minute (-5.2%) in those with severe LUTS (I-PSS greater than 20 at ages 64.3 +/- 7.4 years). On linear regression analysis in the 2 study cohorts neither I-PSS, nor obstructive or irritative score affected GFR (p >0.05). The only determinants for GFR less than 90 ml per minute were age (p <0.0001) and hypertension (p <0.0001). CONCLUSIONS: LUTS do not represent an independent risk factor for impaired renal function in men.

Adult↗
PubMed1999

Longitudinal analysis of factor VIII inhibitors in a previously untreated mild haemophilia A patient with an Arg593-->Cys substitution.

Recent studies suggest that certain missense mutations associated with mild to moderate haemophilia A predispose to inhibitor development. In this study, we present a longitudinal analysis of the epitope specificity of an inhibitor that developed in a mild haemophiliac with an Arg593-->Cys mutation. Immunoprecipitation studies revealed the presence of antibodies directed towards the light chain and A2 domain of factor VIII. Limited reactivity was observed with metabolically labelled C2 domain. Almost complete inhibitor neutralization was achieved upon addition of A2 domain. Binding of the inhibitor was not affected by the presence of the Arg593-->Cys substitution in the recombinant A2 fragment. Evaluation of the epitope specificity of anti-factor VIII antibodies in plasma samples obtained at different time-points of inhibitor development revealed initial development of a low titre inhibitor directed towards the A2 domain and factor VIII light chain. A second period of factor VIII replacement therapy resulted in a dramatic rise in factor VIII inhibitor titre, which maintained their original epitope specificity. Based on the results of this and previous studies (Fijnvandraat et al., 1997; Thompson et al., 1997) it is argued that inhibitor development in patients with the Arg593-->Cys mutation may proceed via a similar mechanism.

Aged↗