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PubMed2004

Serum levels of thiobarbituric acid reactive substances predict cardiovascular events in patients with stable coronary artery disease: a longitudinal analysis of the PREVENT study.

OBJECTIVES: The objective of this study was to test the predictive value of an oxidative stress biomarker in 634 patients from the Prospective Randomized Evaluation of the Vascular Effects of Norvasc Trial (PREVENT). BACKGROUND: Oxidative stress contributes to mechanisms of atherosclerosis and plaque instability. Biomarkers of oxidation, such as malondialdehyde (MDA), may represent independent indicators of risk for patients with stable coronary artery disease (CAD). METHODS: Serum MDA levels were measured as thiobarbituric acid reactive substances (TBARS) in 634 patients with documented CAD using reverse-phase high-performance liquid chromatography and spectrophotometric approaches. RESULTS: During the three-year study, there were 51 major vascular events such as fatal/nonfatal myocardial infarction, 149 hospitalizations for nonfatal vascular events, and 139 patients underwent a major vascular procedure. At baseline, patients with TBARS levels in the highest quartile had a relative risk (RR) of 3.30 (95% confidence interval [CI] 1.47 to 7.42; p = 0.038) for major vascular events, RR of 4.10 (95% CI 2.55 to 6.60; p < 0.0001) for nonfatal vascular events, and RR of 3.84 (95% CI 2.56 to 5.76; p < 0.0001) for major vascular procedures. The effect of TBARS on events and procedures was also seen in a multivariate model adjusted for inflammatory markers (C-reactive protein, soluble intercellular adhesion molecule-1, interleukin-6), and other risk factors (age, low-density lipoprotein, high-density lipoprotein, total cholesterol, triglycerides, body mass index, and blood pressure). This analysis showed an independent effect of TBARS on major vascular events (p = 0.0149), nonfatal vascular events (p < 0.0001), major vascular procedures (p < 0.001), and all vascular events and procedures (p < 0.0001). CONCLUSIONS: Serum levels of TBARS were strongly predictive of cardiovascular events in patients with stable CAD, independently of traditional risk factors and inflammatory markers.

Adult↗
PubMed2007

A longitudinal analysis of serum cytokines in the Hartley guinea pig model of osteoarthritis.

OBJECTIVE: To evaluate chosen serum cytokines and their association with osteoarthritis (OA) in the guinea pig. METHODS: The levels of 18 cytokines were measured in Hartley guinea pig serum at time points ranging from 3 weeks to 18 months of age. These levels were then tested for any correlation with total histology, and a comprehensive evaluation of these statistics was conducted using data previously collected from OA-resistant Strain 13 guinea pigs. RESULTS: After all cytokines demonstrating a significant association with weight or age were excluded, IL-6 (p=0.016) and G-CSF (p=0.024) were found to correlate positively with total histological score. Models involving each of these cytokines paired independently with weight explained 43-44% of the variance in total histology. CONCLUSIONS: Only the age and weight-independent associations of IL-6 and G-CSF with histological OA were significant under the conditions imposed by the Holm step-down adjustment for multiple comparisons. Though the observed changes of these cytokine levels may be due to a correlation with age, it is highly unlikely given the significant difference between Hartley and Strain 13 age-matched cohorts.

Animals↗
PubMed2006

Longitudinal analysis of gray and white matter loss in patients with systemic lupus erythematosus.

Cerebral atrophy has been described to occur in systemic lupus erythematosus (SLE) with variable frequency. The aim of this study was to determine white and gray matter abnormalities in brain magnetic resonance imaging (MRI) of patients with SLE and to determine if these abnormalities progress over a one-year period. Seventy-five patients with SLE and 44 healthy age and sex-matched controls were enrolled in this study. T1-weighted volumetric images were used for voxel based morphometry (VBM) analyses. SLE patients exhibited a significant reduction in white matter and gray matter volume compared to controls (p=0.001). Follow-up images, after an average interval of 19 months, revealed a progressive white matter and gray matter atrophy (p=0.001). Reduced white and gray matter volume was associated with disease duration and the presence of antiphospholipid antibodies. Patients with severe cognitive impairment had a more pronounced white and gray matter reduction than patients with moderate cognitive impairment. Total corticosteroid dose was associated with gray matter reduction and not with white matter loss in SLE patients. We concluded that brain tissue loss associated with SLE is significant and progresses over a relatively short period of time. Disease duration, the presence of antiphospholipid antibodies and cognitive impairment were associated with white and gray matter loss. Corticosteroid was associated only with gray matter atrophy.

Adolescent↗
PubMed2006

Health-related quality of life for men with prostate cancer and diabetes: a longitudinal analysis from CaPSURE.

OBJECTIVES: To compare diabetic versus nondiabetic men with prostate cancer to understand whether diabetes mellitus (DM) imposes an additional burden on health-related quality of life (HRQOL) before and after radical prostatectomy, adjusting for obesity. METHODS: Data were abstracted from Cancer of the Prostate Strategic Urologic Research Endeavor (CaPSURE), a disease registry of 12,005 men with localized prostate cancer. Men were included who had undergone surgical treatment from 1989 to 2003, had body mass index (BMI) information available, and had completed both a pretreatment and at least one posttreatment HRQOL questionnaire within 24 months. A repeated-measures model adjusted for baseline clinical and demographic variables was used to evaluate group differences. RESULTS: The 1248 men were divided into two groups (117 with DM and 1131 without DM) on the basis of a history of DM or the reporting of diabetes medication use. The diabetic men were significantly more likely to be older and nonwhite, have lower education and income, and be less likely to have private insurance. They also had significantly more comorbid conditions (other than DM) and a greater BMI at baseline. Urinary function differed by diabetes status, BMI, and the DM x BMI interaction, with diabetic men who had a greater BMI reporting greater declines in urinary function over time. No other statistically significant differences in HRQOL were observed, although trends by BMI were noted in sexual function and bowel bother. CONCLUSIONS: Although previous studies of men with prostate cancer have found differences in HRQOL by obesity level, our results have indicated that the presence or absence of DM and a high BMI may have a greater impact on HRQOL than obesity alone.

Aged↗
PubMedDate not supplied

Physical violence against impoverished women: a longitudinal analysis of risk and protective factors.

Violence represents a significant threat to the health of impoverished women. Few studies have examined what characteristics might be associated with increased risk of violence or protection from physical violence directed at such women, although this information is important in informing violence prevention and intervention efforts. This is the first study to our knowledge that has prospectively examined, in representative probability samples of impoverished women, multiple risk and protective factors to understand their relative importance to physical victimization. Study participants were 810 women in Los Angeles County, 402 in shelters and 408 in Section 8 low-income housing, who completed structured interviews at baseline and 6-month follow-up. Significant (p < .05) multivariate predictors of physical violence experienced during the 6 months prior to follow-up interview were physical or sexual violence experienced as a child, physical violence experienced during the 6 months prior to baseline interview, having multiple sexual partners, psychological distress, and poor social support. Results of this study highlight the persistence of physical violence in the lives of impoverished women and plausible, prospective risk factors for this violence. Findings also highlight opportunities to reduce women's risk of experiencing violence through enhancing women's social support and mental health.

Adult↗
PubMed2002

Natural history of traumatic rupture of the thoracic aorta managed nonoperatively: a longitudinal analysis.

BACKGROUND: Although traumatic rupture of the thoracic aorta (TRA) has traditionally been considered a surgical emergency, there exists a small patient population for whom nonoperative management may be appropriate. The short- and long-term consequences of patients managed in a nonoperative fashion remain unclear. METHODS: A review of patients admitted with TRA over a period of 16 years was performed. Patients who did not undergo operative repair within 24 hours of injury and diagnosis comprised the study group. RESULTS: One hundred forty-five patients were admitted with TRA. Of these, 30 underwent a period of nonoperative management. The mean age of the study patients was 44 +/- 21 years, 80% were male, and the mean Injury Severity Score (ISS) was 34 +/- 9. Fifteen patients underwent delayed operation (DELAY group) at more than 24 hours after injury and diagnosis and 15 patients never underwent repair (NON-OP group). The median time to operation in the DELAY group was 3 days (range 2 to 90). Three patients exhibited progression of TRA within 5 days of injury and of these, 2 died. A total of 3 deaths occurred in the DELAY group (1 rupture and 2 intraoperative arrests). The fifteen NON-OP patients were significantly older (mean age 52 +/- 22 versus 36 +/- 18 years; p = 0.03), tended to be more severely injured (mean ISS 36 +/- 9 versus 32 +/- 8; p = 0.2), and had more premorbid risk factors than the DELAY patients. Five NON-OP patients died, all because of severe head injuries. On long-term follow-up of NON-OP patients, all 10 survivors are alive at a median of 2.5 years (range 6 months to 5 years) without progression of injury or the need for operation. Five of the 10 had complete radiographic resolution of their injuries and 5 have asymptomatic and radiographically stable pseudoaneurysms. CONCLUSIONS: Selected patients with multiple severe associated injuries or high-risk premorbid conditions may have their operations for TRA delayed temporarily or even indefinitely with acceptable survival rates. The potential for rapid progression of TRA in the same patients, however, mandates serial radiographic examinations during the first week of hospitalization after injury and diagnosis.

Adult↗
PubMed1988

Surgical management of aortic valve disease in the elderly: a longitudinal analysis.

From November, 1972, through December, 1986, 219 consecutive patients 70 years of age and older with aortic stenosis (AS) underwent aortic valve replacement. One hundred seven of them had isolated pure AS, and 112 had AS and coronary artery disease (AS + CAD). The mean age of the AS group was 75.4 years (range, 70 to 88 years) and of the AS + CAD group, 74.8 years (range, 70 to 86 years). The mean aortic valve gradient in the AS group was 87.7 +/- 30.6 mm Hg and in the AS + CAD group, 68.0 +/- 51.3 mm Hg (p less than 0.001). Hospital mortality for the AS group was 12.1% (13 patients) and for the AS + CAD group, 8.9% (10 patients). The long-term survival at seven years was 77.2 +/- 5.5% (+/- the standard error of the mean) for the AS group and 57.0 +/- 6.9% for the AS + CAD group (p less than 0.006). Postoperative assessment reveals substantial functional improvement. These early and long-term favorable results provide a much needed reference point when valvuloplasty is being considered. Aortic valve replacement is the treatment of choice in elderly patients with symptomatic AS.

Actuarial Analysis↗
PubMed2000

Longitudinal analysis of symptoms reported by patients with chronic fatigue syndrome.

PURPOSE: To determine the effect of chronic fatigue syndrome (CFS) illness duration and onset type on the likelihood of reporting a symptom during successive follow-up periods.METHODS: In 1997, a two-phase RDD survey in Wichita, Kansas, was conducted to estimate the prevalence of CFS. Phase I identified 56,154 respondents 18-69 years of age and screened for severe fatigue, extreme tiredness or exhaustion lasting for 1 month or longer. In phase II an equal number of fatigued (n = 7,176) and randomly selected non-fatigued subjects were asked about 8 CFS and 13 non-CFS symptoms, as well as the presence of specific medical and psychiatric conditions. Eligible respondents were clinically evaluated to establish CFS diagnosis. Phase II respondents were re-contacted at 12- (n = 4,331) and 24-months (n = 4,266) for additional follow-up and diagnosis. In this study we considered symptoms reported as being present most of the time during each successive observation period. Generalized estimating equations were used to model symptoms over time and to address study questions. Such a model accounts for correlations among repeated symptoms for each subject. We used an auto-regressive structure for the correlation matrix, assuming the correlations between each pair of repeated symptoms should decrease as the time between symptoms increased.RESULTS: There were 74 CFS patients who had been ill for 1 to 20 years (median = 6.3 years). Among these, 46 reported gradual and 28 reported sudden onset. Symptoms fluctuated over the course of illness. However, only stomach pain (non-CFS symptom) was more likely to be reported as duration of illness increased (p < 0.05). There was no association between onset type and the likelihood of reporting a symptom during an interview, except that chills and severe headaches were more likely to be reported by sudden cases.CONCLUSIONS: The likelihood of expressing CFS and non-CFS symptom "most of the time" is the same across years of illness. More analyses are warranted to consider expression of symptoms for >/=6 months and severe symptoms.

Journal Article↗
PubMed1992

Longitudinal analysis of a two-component model of the memory deficit in Alzheimer's disease.

The memory deficit in Alzheimer's disease (AD) has been characterized as consisting of multiple components. The purpose of this study was to confirm the utility of a two-process model, and to examine changes in the nature and extent of the neuropsychological deficits after a one-year interval. The results replicate the initial observation that the memory loss in AD can be described as consisting of a focal amnesic syndrome and a dysexecutive syndrome characterized by failure of rapid information processing and search of both episodic and semantic memory. One year after the initial observation, all dysexecutive patients and the majority of the amnesic patients had become non-focal. No patient developed a dysexecutive syndrome, but 18 patients developed amnesic syndromes. These results suggest that, like other aspects of the cognitive deficits of AD, the memory loss is multifactorial. These results have implications for understanding the pathophysiology of AD, and for designing pharmacotherapeutic intervention.

Aged↗
PubMed2002

A longitudinal analysis of patterns of adjustment following peer victimization.

This study examined the effects of being victimized by peers on children's behavioral, social, emotional, and academic functioning. We assessed an ethnically diverse sample of 2,064 first, second, and fourth graders and followed them over 2 years, locating 1,469 of the participants at the follow-up. Correlation and partial correlation analyses revealed that prior victimization predicted externalizing, internalizing, and social problems 2 years later for the sample as a whole. However, not all victimized children experienced the same types of outcomes; instead, there was heterogeneity in children's responses to victimization. Using cluster analysis, we identified eight outcome patterns that represented different patterns of functioning. These were labeled as externalizing, internalizing, symptomatic, popular, disliked, absent, low achieving, and high achieving. Discriminant function analyses revealed that the symptomatic, externalizing, and disliked patterns were systematically related to victimization. Moreover, significant gender and age differences in the severity of effects were obtained. The discussion highlights the complexity of victimization effects.

Aggression↗
PubMed2002

A longitudinal analysis of friendships and substance use: bidirectional influence from adolescence to adulthood.

The reciprocal relation between deviant friendships and substance use was examined from early adolescence (age 13-14) to young adulthood (age 22-23). Deviance within friendships was studied using direct observations of videotaped friendship interaction and global reports of deviant interactions with friends as well as time spent with friends. Substance use was assessed through youth self-report at all time points. Multivariate modeling revealed that substance use in young adulthood is a joint outcome of friendship influence and selection processes. In addition, substance use appears to influence the selection of friends in late adolescence. Findings suggest that effective preventions should target peer ecologies conducive to substance use and that treatment should address both the interpersonal underpinnings and addiction processes intrinsic to chronic use, dependence, and abuse.

Adolescent↗
PubMed2003

A longitudinal analysis of organizational fairness: an examination of reactions to tenure and promotion decisions.

Most organizational justice research takes a cross-sectional approach to examining the relationship between perceived fairness and individuals' attitudes. This study examines the effect of procedural and distributive justice over time. It is suggested that individuals acquire more information and experience with procedures and outcomes over time. These changes in information and experience affect the influence of procedural and distributive justice on organizational attitudes. Faculty perceptions of tenure and promotion decisions were assessed 3 times (preallocation, short-term postallocation, long-term postallocation) over a 2-year period. Results generally supported the hypotheses. Procedural justice was most influential prior to and soon after outcome decisions were made. Distributive justice was most influential 1 year later.

Adult↗
PubMed2004

A longitudinal analysis of PTSD symptom course: delayed-onset PTSD in Somalia peacekeepers.

Posttraumatic stress disorder (PTSD) typically follows an acute to chronic course. However, some trauma victims do not report significant symptoms until a period of time has elapsed after the event. Although originally dismissed as an artifact of retrospective methodologies, recent prospective studies document apparent instances of delayed-onset PTSD. Little is known currently about factors associated with the delayed onset of PTSD. This study was designed to examine the course of PTSD in a sample of 1,040 U.S. military peacekeepers who served in Somalia. A small but nontrivial subset of participants endorsed clinically significant levels of PTSD after a period of minimal distress, the magnitude of which cannot be ascribed to minor waxing and waning of symptoms. War-zone exposure and perceived meaningfulness of the mission, as rated by soldiers after returning to the United States, predicted symptom course over the next 18 months.

Adult↗
PubMed2006

Longitudinal analysis of the relationship between symptoms and quality of life in veterans treated for posttraumatic stress disorder.

This study examined how change in posttraumatic stress disorder (PTSD) symptoms relates to change in quality of life. The sample consisted of 325 male Vietnam veterans with chronic PTSD who participated in a randomized trial of group psychotherapy. Latent growth modeling was used to test for synchronous effects of PTSD symptom change on psychosocial and physical health-related quality of life within the same time period and lagged effects of initial PTSD symptom change on later change in quality of life. PTSD symptoms were associated with reduced quality of life before treatment. There were synchronous effects of symptom change on change in quality of life but no significant lagged effects. Results indicate the importance of measuring quality of life in future investigations of PTSD treatment.

Adult↗
PubMed1992

Temperament and adjustment in young adulthood: a 15-year longitudinal analysis.

The relationship between easy/difficult temperament and adjustment from middle adolescence to young adulthood was examined. Cluster analysis revealed four groups of individuals via composite temperament scores over three points of measurement. Multivariate analyses indicated that extremely difficult temperament was associated with poorer psychosocial functioning in childhood and young adulthood.

Adaptation, Psychological↗
PubMed2005

Longitudinal analysis of the group A Streptococcus transcriptome in experimental pharyngitis in cynomolgus macaques.

Identification of the genetic events that contribute to host-pathogen interactions is important for understanding the natural history of infectious diseases and developing therapeutics. Transcriptome studies conducted on pathogens have been central to this goal in recent years. However, most of these investigations have focused on specific end points or disease phases, rather than analysis of the entire time course of infection. To gain a more complete understanding of how bacterial gene expression changes over time in a primate host, the transcriptome of group A Streptococcus (GAS) was analyzed during an 86-day infection protocol in 20 cynomolgus macaques with experimental pharyngitis. The study used 260 custom Affymetrix (Santa Clara, CA) chips, and data were confirmed by TaqMan analysis. Colonization, acute, and asymptomatic phases of disease were identified. Successful colonization and severe inflammation were significantly correlated with an early onset of superantigen gene expression. The differential expression of two-component regulators covR and spy0680 (M1_spy0874) was significantly associated with GAS colony-forming units, inflammation, and phases of disease. Prophage virulence gene expression and prophage induction occurred predominantly during high pathogen cell densities and acute inflammation. We discovered that temporal changes in the GAS transcriptome were integrally linked to the phase of clinical disease and host-defense response. Knowledge of the gene expression patterns characterizing each phase of pathogen-host interaction provides avenues for targeted investigation of proven and putative virulence factors and genes of unknown function and will assist vaccine research.

Animals↗