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PubMed2005

Exhaled carbon monoxide levels in atopic asthma: a longitudinal study.

Exhaled carbon monoxide (eCO) is a potential non-invasive marker of airway inflammation. We have investigated the cross-sectional and longitudinal relationship between eCO and lung function and bronchial reactivity in 69 adults with atopic asthma, in the course of participation in a 6-week randomised placebo-controlled trial of vitamin E supplementation. At baseline, there was no cross-sectional association between absolute eCO levels and either forced expiratory volume (FEV(1)), forced vital capacity (FVC) or bronchial reactivity. However, in the longitudinal analysis within the placebo group, a rise in mean eCO was significantly associated with improvement in bronchial reactivity (change in eCO (parts per million) per natural log unit change in bronchial hyperreactivity 0.498, 95% confidence interval 0.071 to 0.924, P=0.024). These findings suggest that, contrary to previous data, there is no cross-sectional relationship between eCO and lung function or bronchial reactivity, but that there may be a longitudinal trend with bronchial reactivity that is worth further investigation.

Adolescent↗
PubMedDate not supplied

[Griffith test in the evaluation of psychomotor development in the 1st year of life. A longitudinal study].

Griffith psychometric test has been experimented on a group of 20 healthy newborn infants, monitored during their 1st year of life with quarterly check-ups. It was clear that the development general rates were constantly higher than the original values reported by the English author. In particular, in 12 months old infants, the rates appeared significantly higher than the rates observed on the same Italian specimen in past periods. A transverse and longitudinal study of the psychomotor development of subjects included in the specimen has given the opportunity to verify some of his features. The development outlines, traced by employing the average rates relevant to the 5 different aspects monitored (motor, personal-social, language, eye-hand co-ordination, practical reasoning), appeared to be well-balanced, that is without dissynchronisms between the different scales. The only exception being the scale of the social behaviour, were the average rates appear to be sensibly higher at every age. Individual development outlines, on the contrary, appeared to be disjointed in all aspects (except for 4 cases). In the longitudinal analysis then, some noteworthy oscillations in both general and partial rates, were observed among the controls carried out in subsequent periods in all the subjects.

Child Development↗
PubMed1994

Surgery for aortic stenosis in elderly patients. A study of surgical risk and predictive factors.

BACKGROUND: Aortic stenosis is the most common valvular lesion occurring among elderly patients and has become extremely frequent because of changing demographics in industrialized countries. Surgical risk after the age of 70 has increased. The increasing older age of patients having surgery justifies an analysis of mortality predictive factors. METHODS AND RESULTS: Between 1976 and February 1993, we performed 2871 operations for aortic stenosis. This study concerns 675 patients (278 men and 397 women) who were > or = 75 years old. Mean age was 78.5 +/- 3 years. Associated lesions were found in 226 patients. A bioprosthesis was implanted in 632 patients (93.6%). Concomitant surgical procedures were performed in 133 patients. Surgical mortality was 12.4% (84 deaths). A longitudinal analysis has been carried out over four successive time periods to evaluate population evolution during these 17 years. Statistical analysis was performed on 46 variables. Multivariate analysis found age (P < .0001), left ventricular failure (P < .0001), lack of sinus rhythm (P < .01), and emergency status (P < .02) to be presurgical independent predictive factors of mortality. CONCLUSIONS: Risk-reducing strategy should both favor relatively early surgery to avoid cardiac failure and emergency situations and pay careful attention to the use of myocardial protection and cardiopulmonary bypass. Indications for surgery should remain broad since analysis failed to determine specific high-risk groups to be eliminated, and surgery remains the only treatment for aortic stenosis.

Age Factors↗
PubMed2005

A multilevel examination of the relationships among training outcomes, mediating regulatory processes, and adaptive performance.

This study examined whether cognitive, affective-motivational, and behavioral training outcomes relate to posttraining regulatory processes and adaptive performance similarly at the individual and team levels of analysis. Longitudinal data were collected from 156 individuals composing 78 teams who were trained on and then performed a simulated flight task. Results showed that posttraining regulation processes related similarly to adaptive performance across levels. Also, regulation processes fully mediated the influences of self- and collective efficacy beliefs on individual and team adaptive performance. Finally, knowledge and skill more strongly and directly related to adaptive performance at the individual than the team level of analysis. Implications to theory and practice, limitations, and future directions are discussed.

Adaptation, Psychological↗
PubMed2004

Reproductive success in presenescent common gulls (Larus canus): the importance of the last year of life.

Survival selection against individuals of inferior quality (measured as breeding success) has been proposed to account for the increase in average reproductive success with advancing age in presenescent birds. This so-called selection hypothesis relies on quality-dependent survival. In the present breeding performance study of common gulls, Larus canus, this assumption was not verified. In particular, omitting the last breeding year from the analysis resulted in the disappearance of the correlation between breeding success and survival. A positive correlation in the full dataset was thus solely based on the poor breeding success of ultimate breeders. Indeed, presenescent individuals were shown to have a specifically low breeding success in their terminal breeding event. The poor success of ultimate breeders thus reflects an abruptly declined condition rather than the birds' overall quality. A comparison of the survival of poor and good performers, involving last-time breeders, thus needs not to be a proper test of the selection hypothesis. Longitudinal analysis revealed a steady increase of individual breeding success until the tenth breeding year. The results suggest that an increase of breeding success with age often found in cross-sectional analyses is primarily a result of age-related improvements of competence and/or increased reproductive effort.

Age Factors↗
PubMed2001

Growth patterns and final height in congenital adrenal hyperplasia due to classical 21-hydroxylase deficiency. Results of a multicenter study.

BACKGROUND: Longitudinal growth and bone age (BA) development are the most important clinical parameters for monitoring adequate glucocorticoid replacement in children with congenital adrenal hyperplasia (CAH). AIM OF THE STUDY: To analyze the growth pattern of patients treated for CAH of the salt wasting (SW) and simple virilizing (SV) clinical forms; to evaluate final height as compared to reference data and individual target height; to evaluate the course of BA development. PATIENTS AND METHODS: A large database of 598 patients with CAH was created in 5 Central European countries and growth data of 341 treated patients with 21-hydroxylase deficiency were analyzed retrospectively. The patients were of Caucasian origin. Centiles were constructed in a cross-sectional manner and an additional longitudinal analysis was performed in order to evaluate the pubertal growth spurt by applying particular statistical methods (Preece-Baines model). RESULTS: The growth of SW CAH patients was impaired in infancy and early childhood (0-3 years of age), but followed normal patterns in childhood until puberty. In contrast, children with SV CAH had normal patterns of growth in infancy and early childhood and were considerably taller than healthy references during childhood. In the longitudinal study, peak height velocity in both boys and girls was normal, but it occurred at an earlier age than in the standard population. The final height of patients with CAH was reduced in comparison to both the reference and the individual target height. No correlations were found between final height and age at the start of the therapy in SV patients or between final height and year of birth. BA was advanced in both types of CAH, but more accelerated in SV patients. CONCLUSION: Characteristic growth patterns for treated SV and SW CAH children were identified, with a normal pubertal growth spurt and reduced final height being observed.

Adolescent↗
PubMed2005

Changes in platelet monoamine oxidase activity, cholesterol levels and hyperactive behaviour in adolescents over a period of three years.

Platelet monoamine oxidase (MAO) activity is a peripheral marker of central serotonergic activity, and has been associated with aggressive, impulsive and hyperactive behaviour, alcohol and drug abuse. Central serotonergic activity has also been associated with plasma cholesterol levels. In the present longitudinal investigation in adolescents (n = 320) changes in platelet MAO activity and in plasma cholesterol levels over three years were measured, and their possible association with changes in aggressive and hyperactive behaviour, smoking, alcohol and drug use was studied. The measures were taken at age 15 and 18 years. Psychological data were obtained from teachers by using the Hyperactivity Scale [B. af Klinteberg, Studies on Sex-related Psychological and Biological Indicators of Psychosocial Vulnerability: A Developmental Perspective, University of Stockholm, Department of Psychology, 1988]. The results of the study show that in most of the tested individuals, platelet MAO activity is a relatively stable measure, however, there was a significant number of subjects with a noticeable change in MAO activity. In subjects with decreased platelet MAO activity, total and HDL cholesterol levels were significantly increased. Also, changes in HDL cholesterol and in platelet MAO activity were inversely associated with changes in the score of Concentration Difficulties. The changes in platelet MAO activity and cholesterol level were not associated with alcohol and drug use among the subjects. This longitudinal analysis provides preliminary evidence that changes in platelet MAO activity and cholesterol, which may reflect changes in central serotonergic activity are associated with attention deficit in adolescents.

Adolescent↗
PubMed1992

Clinical manifestations and anti-(U1)snRNP antibodies: a prospective study of 29 anti-RNP antibody positive patients.

Twenty-nine anti-RNP positive patients were followed prospectively with a mean observation time of 65 months (29-120 months). The clinical course was correlated to the presence of IgM and IgG anti-(U1)snRNP antibodies as revealed by immunoblotting from sequentially obtained sera. There was a striking dissociation between the fluctuating course, with the appearance of new manifestations followed by remissions, and the stability of the anti-snRNP antibody specificities where an appearance or a disappearance of anti-snRNP specificities was a rare phenomenon. The main epitope recognized by the IgG antibodies was the 70 kDa protein and of the IgM antibodies the B/B' proteins. No shift from the IgM to the IgG isotype was observed. The presence of IgG anti-70 kDa and IgM anti-B/B' antibodies was highly associated with presence of arthralgias, Raynaud's phenomenon and arthritis. Further, an association was noted between the combined presence of IgG anti-70 kDa, anti-A and anti-C antibodies and IgM anti-B/B' and puffy hands, myositis, pulmonary fibrosis and sclerodactyly, i.e. all manifestations of mixed connective tissue disease (MCTD). On the contrary, serositis as often seen in SLE was correlated to the presence of IgG anti-B/B' antibodies. Thus the longitudinal analysis of the correlation between anti-snRNP antibody specificities and clinical manifestations support the concept of MCTD as a distinct entity.

Adolescent↗
PubMed1992

The protracted demise of medical technology. The case of intermittent positive pressure breathing.

In this study, the effects of hospital, staff, and patient characteristics on the rates of use and abandonment of an outmoded medical technology, intermittent positive pressure breathing (IPPB) are analyzed. The study focuses specifically on the use of IPPB to treat inpatients with chronic obstructive pulmonary disease in a national sample of more than 500 community hospitals from 1980 to 1987. Cross-sectionally, hospitals with shorter case-mix-adjusted lengths of stay, private nonprofit or investor-owned hospitals, and hospitals located outside of the north central United States were more likely to abandon IPPB by 1980. Teaching status, location, ownership, volume, and source of payment all appeared to affect rates of IPPB use in 1980. The longitudinal analysis examines both the probability a hospital abandoned IPPB and declines in rates of IPPB use over the study period, conditioned on the availability of IPPB in 1980. The results show that changes in the characteristics of hospitals, patients, and physicians all help to explain variations in the abandonment of IPPB. These findings contrast with previous studies of technological change, which find hospital size to be the most important variable. Size is important in explaining the rate of use in 1980, but it has no effect on the rate of decline in use or abandonment after 1980. In general, the analysis demonstrates that a combination of factors, economic incentives as well as information, contribute to the abandonment of outmoded medical technologies. Given the surprisingly long time periods required for this process to occur, the analysis underscores the need to strengthen financial incentives that encourage appropriate medical decisions and to disseminate information about the efficacy of specific procedures more widely and effectively.

Cross-Sectional Studies↗
PubMed1998

Occupational determinants of work attitudes and organizational attachment.

The "work attitudes-turnover" linkage was compared among four medical-sector occupational groups. In a sample of 707 employees, drawn from eight variously-sized medical-sector sites, intended and actual turnover behavior is predicted. Combining a cross-sectional and longitudinal analysis, and using two logistic regression models, the direct effect of work attitudes on intended and actual turnover was assessed. The "work attitudes-turnover" was shown to be occupationally-dependent.

Age Factors↗
PubMed2003

Sputum cytological atypia as a predictor of incident lung cancer in a cohort of heavy smokers with airflow obstruction.

Individuals with cytological atypia in sputum may be at increased risk for lung cancer. We conducted a longitudinal analysis of the association between lung cancer incidence and cytological atypia in sputum samples collected prospectively from an ongoing cohort of adults at high risk for lung cancer. Cohort members had a smoking history of > or = 30 pack-years and chronic obstructive pulmonary disease documented by pulmonary airflow testing. Sputum samples collected at baseline and periodically thereafter were examined by standard cytological methods. From the cohort of 2,006 people, there were 83 incident lung cancers over 4,469 person-years of observation. At baseline, the association between personal and behavioral characteristics, and sputum cytological atypia was assessed by multiple logistic regression. The association between sputum cytological atypia and incident lung cancer was then assessed by hazard ratios using proportional hazards regression analysis, adjusting for potential confounding factors. Cytological atypia graded as moderate or worse was associated with continuing cigarette smoking (adjusted odds ratio, 2.5; 95% confidence interval, 1.5-4.1), and with lower levels of intake of fruits and vegetables (P for trend = 0.04). Atypia was not associated with several other factors, including the degree of airflow obstruction, the use of vitamin supplements, nonsteroidal anti-inflammatory drugs, or metered-dose steroid inhalers. Incident lung cancer was increased among those with moderate or worse cytological atypia (adjusted hazards ratio, 2.8; 95% confidence interval, 1.4-5.5). This association was not confounded by other risk factors. We conclude that in this high-risk cohort, cytological atypia is associated with continuing smoking and low intake of fruits and vegetables, but that independent of these and other factors, the risk of incident lung cancer is increased among those with moderate or worse grades of cytological atypia in their sputum.

Adult↗
PubMed1991

An analysis of occupational blood lead trends in Manitoba, 1979 through 1987.

BACKGROUND: While regulations for workplace lead exposure become more strict, their effectiveness in decreasing blood lead concentrations and the method by which this is attained have not been evaluated. METHODS: An analysis was conducted of 10,190 blood lead samples from employees of 10 high-risk workplaces collected in Manitoba, 1979-87, as part of regulated occupational surveillance. RESULTS: A significant decrease in blood lead concentrations was observed overall as well as for each individual company. A 1979 government regulation to reduce blood lead to below 3.38 mumol/L (70 micrograms/dl) was followed by a drop in blood lead concentrations; a 1983 order to reduce blood leads to below 2.90 mumol/L (60 micrograms/dl) was not followed by such a drop. Longitudinal analysis by individual workers suggested that companies were complying by use of administrative control, i.e., removing workers to lower lead areas until blood lead levels had fallen, then returning them to high lead areas. CONCLUSION: Focusing upon blood lead as the sole criterion for compliance is not effective; regulations must specifically require environmental monitoring and controls. Biological surveillance serves as "back-up" to environmental surveillance and this database illustrates the usefulness of a comprehensive centralized surveillance system.

Air Pollutants, Occupational↗
PubMed1998

Cotinine excretion as a predictor of peak flow variability.

Environmental tobacco smoke (ETS) is suspected to be an important risk factor for bronchial hyperresponsiveness. In order to test the effect of ETS, we measured expiratory flow rates and urine cotinine excretion (UCE) within a narrow time window in two consecutive years. Maternal smoking habits and medical history were ascertained by standardized questionnaires. The percentage ratio of the amplitude over the mean (AVAM) of the diurnal peak flow rates of children (complete values from at least five consecutive days) was calculated as an indicator of bronchial responsiveness. The association of UCE and log10AVAM was analyzed by multiple linear regression. Complete data were available for a sample of 417 children. The median of UCE in children of parents who smoked (3.2 ng/mg and 2.9 ng/mg creatinine, Surveys 1 and 2, respectively) was higher than the median in children of nonsmoking parents (0 ng/mg in both surveys). With increasing UCE the log10AVAM rose in the first and second surveys, as well as in the longitudinal analysis (p = 0.003). This association, however, showed up only in boys (p = 0.0001) and not in girls (p = 0.31). Our data suggest that there is a need both for further analysis of the gender difference and for more support of strategies against passive smoking as far as children are concerned, since airway hyperresponsiveness is a risk factor for chronic airway impairment.

Asthma↗
PubMed2002

Vaccination with a Melan-A peptide selects an oligoclonal T cell population with increased functional avidity and tumor reactivity.

Both the underlying molecular mechanisms and the kinetics of TCR repertoire selection following vaccination against tumor Ags in humans have remained largely unexplored. To gain insight into these questions, we performed a functional and structural longitudinal analysis of the TCR of circulating CD8(+) T cells specific for the HLA-A2-restricted immunodominant epitope from the melanocyte differentiation Ag Melan-A in a melanoma patient who developed a vigorous and sustained Ag-specific T cell response following vaccination with the corresponding synthetic peptide. We observed an increase in functional avidity of Ag recognition and in tumor reactivity in the postimmune Melan-A-specific populations as compared with the preimmune blood sample. Improved Ag recognition correlated with an increase in the t(1/2) of peptide/MHC interaction with the TCR as assessed by kinetic analysis of A2/Melan-A peptide multimer staining decay. Ex vivo analysis of the clonal composition of Melan-A-specific CD8(+) T cells at different time points during vaccination revealed that the response was the result of asynchronous expansion of several distinct T cell clones. Some of these T cell clones were also identified at a metastatic tumor site. Collectively, these data show that tumor peptide-driven immune stimulation leads to the selection of high-avidity T cell clones of increased tumor reactivity that independently evolve within oligoclonal populations.

Amino Acid Sequence↗
PubMed2006

Pacemaker implantation and quality of life in the Mode Selection Trial (MOST).

BACKGROUND: Dual-chamber pacemakers restore AV synchrony compared with ventricular pacemakers, but the effects on health-related quality of life (QOL) are uncertain. OBJECTIVES: The purpose of this study was to assess the effect of pacemaker implantation, clinical factors, and pacing mode on QOL. METHODS: The Mode Selection Trial (MOST) randomized 2,010 patients with sinus node dysfunction to rate-modulated right ventricular (VVIR) or dual-chamber (DDDR) pacing. A longitudinal analysis of serial QOL measures (Short Form-36 [SF-36], Specific Activity Scale, and time trade-off utility) was performed. In patients who crossed over from VVIR to DDDR because of severe pacemaker syndrome, the last known QOL prior to crossover was carried forward. RESULTS: Pacemaker implantation resulted in substantial improvement in almost all QOL measures. Subjects 75 years or older experienced significantly less improvement in functional status and physical component summary scores than did younger subjects. In longitudinal analyses of the effect of pacing mode on QOL, significant improvement in three SF-36 subscales was observed with DDDR pacing compared with VVIR pacing: role physical [62.8 points (95% confidence interval [CI] 60.2, 65.5) vs 56.4 (95% CI 53.7, 59.1)], role emotional [85.0 (95% CI 82.9, 87.0) vs 81.9 (95% CI 79.9, 84.0)], and vitality [51.8 (95% CI 50.3, 53.3) vs 49.3 (95% CI 47.8, 50.7)], but not in other SF-36 subscales, the Specific Activity Scale, or utilities. The gains in QOL were larger than the declines associated with 1 year of aging but smaller than those associated with heart failure. CONCLUSION: Pacemaker implantation improved health-related QOL. The mode selected was associated with much smaller, but significant, improvements in several domains, particularly role physical function.

Aged↗
PubMed1998

High body fatness, but not low fat-free mass, predicts disability in older men and women: the Cardiovascular Health Study.

Using data from the Cardiovascular Health Study, we studied the relation between body composition (fat mass and fat-free mass, assessed by bioelectrical impedance) and self-reported, mobility-related disability (difficulty walking or stair climbing) in 2714 women and 2095 men aged 65-100 y. In a cross-sectional analysis at baseline (1989-1990), disability was reported by 26.5% of the women and 16.9% of the men. A positive association was observed between fat mass and disability. The odds ratio for disability in the highest quintile of fat mass was 3.04 (95% CI: 2.18, 4.25) for women and 2.77 (95% CI: 1.82, 4.23) for men compared with those in the lowest quintile. Low fat-free mass was not associated with a higher prevalence of disability. In a longitudinal analysis among persons not reporting disability at baseline, 20.3% of the women and 14.8% of the men reported disability 3 y later. Fat mass at baseline was predictive of disability 3 y later, with odds ratios of 2.83 (95% CI: 1.80, 4.46) for women and 1.72 (95% CI: 1.03, 2.85) for men in the highest quintile of fat. The increased risk was not explained by age, physical activity, chronic disease, or other potential confounders. Low fat-free mass was not predictive of disability. The results showed that high body fatness is an independent predictor of mobility-related disability in older men and women. These findings suggest that high body fatness in old age should be avoided to decrease the risk of disability.

Adipose Tissue↗
PubMedDate not supplied

Assessing the offending activity of criminal domestic violence suspects: offense specialization, escalation, and de-escalation evidence from the Spouse Assault Replication Program.

OBJECTIVE: Over the past quarter century, intimate partner violence research has occupied an increasingly important position in the research agenda of criminology, public policy, and public health. Yet, a number of questions about the criminal careers of domestic violence offenders remain unresolved. This study attempts to determine (1) the extent to which criminal domestic violence offenders specialize in violence, and (2) whether the severity of an offender's attacks against the same victim increase, decrease, or stay about the same over time. METHODS: Data from the Spouse Assault Replication Program (SARP) are used to address two questions corresponding to different features of the criminal careers of domestic violence offenders. RESULTS: The specialization analysis reveals that the majority of domestic violence offenders with prior official criminal records have been involved in nonviolent forms of criminal behavior in addition to domestic violence. The escalation analysis identifies groups of escalators and de-escalators as well as individuals who engage in stable low-level aggression and stable high-level aggression. CONCLUSIONS: Few SARP domestic violence offenders have been specializing exclusively in violence. There is also a heterogeneous mix of offenders who escalate and de-escalate the severity of their attacks over the short-term follow-up periods. Few studies have presented data consistent with the present study's findings. A longitudinal analysis of the criminal careers of domestic violence offender subtypes is critical for future research.

Criminal Law↗
PubMed2005

Structural factors associated with malalignment in knee osteoarthritis: the Boston osteoarthritis knee study.

OBJECTIVE: Osteoarthritis (OA) is a multifactorial condition. The progression of knee OA is determined in part by mechanical effects on local structures. One of the mechanical influences on cartilage loss is limb alignment. We explored the structural factors associated with malalignment in subjects with symptomatic OA. METHODS: We conducted a cross-sectional assessment using The Boston Osteoarthritis of the Knee Study, a natural history study of symptomatic knee OA. Baseline assessments included knee magnetic resonance imaging (MRI) and information on weight and height. Long-limb radiographs to assess mechanical alignment were obtained at 15 months. Subarticular bone attrition, meniscal degeneration, anterior and posterior cruciate ligament integrity, medial and lateral collateral ligament integrity, marginal osteophytes, and cartilage morphology were assessed on MRI using a semiquantitative, multi-feature scoring method (Whole-Organ MRI Score) for whole-organ evaluation of the knee that is applicable to conventional MRI techniques. We also quantified the following meniscal position measures on coronal MRI images in both medial and lateral compartments: subluxation, meniscal height, and meniscal covering of the tibial plateau. Using the long-limb radiographs, mechanical alignment was measured in degrees on a continuous scale. The purpose of this cross-sectional analysis was to determine the individual and relative contribution of various structural factors to alignment of the lower extremity. We assessed the cross-sectional association between various structural factors and alignment of the lower extremity using a linear regression model. RESULTS: The 162 subjects with all measures acquired had a mean age of 67.0 years (SD 9.2), body mass index 31.4 (SD 5.6); 30% were female and 77% of knees had a Kellgren-Lawrence grade > or = 2. The main univariate determinants of varus alignment in decreasing order of influence were medial bone attrition, medial meniscal degeneration, medial meniscal subluxation, and medial tibiofemoral cartilage loss. Multivariable analysis revealed that medial bone attrition and medial tibiofemoral cartilage loss explained more of the variance in varus malalignment than other variables. The main univariate determinants of valgus malalignment in decreasing order of influence were lateral tibiofemoral cartilage loss, lateral osteophyte score, and lateral meniscal degeneration. CONCLUSION: Cartilage loss has been thought to be the major determinant of alignment. We found that other factors including meniscal degeneration and position, bone attrition, osteophytes, and ligament damage contribute to the variance of malalignment. Further longitudinal analysis is required to determine cause and effect relationships. This should assist researchers in determining strategies to ameliorate the potent effects of this mechanical disturbance.

Aged↗