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PubMed2000

Maintenance of bone density: outcomes over five years of attendance at an osteoporosis center.

BACKGROUND: This is a longitudinal analysis of the data from women who visited the Osteoporosis Prevention Center for at least five years. The study is part of an ongoing evaluation of the results of the Center visits. METHODS: A random sample of 100 women who had attended the clinic for more than five years and were not referred for a definite medical diagnosis was pulled from the records. Descriptive statistics were compiled on this sample. Seventy-five women were postmenopausal and over 49 years of age. This subgroup was studied for change in bone mineral density (BMD) over the five years. RESULTS: The BMD change was 0.03 gm/cm2 in the spine, -0.01 gm/cm2 in the femoral-neck. and -0.008 gm/cm2 at the radius over the five years. CONCLUSION: Attendance at the Osteoporosis Prevention Center was associated with maintenance of bone density in the spine over a five-year period.

Aged↗
PubMed2025

A blood-based DNA damage signature in patients with Parkinson's disease is associated with disease progression.

Aging is the main risk factor for Parkinson's disease (PD), yet our understanding of how age-related mechanisms contribute to PD pathophysiology remains limited. We conducted a longitudinal analysis of blood samples from the Parkinson's Progression Markers Initiative cohort to investigate DNA damage in PD. Patients with PD exhibited disrupted DNA repair pathways and biased suppression of longer transcripts, indicating age-related, transcription-stalling DNA damage. Notably, at the intake visit, this DNA damage signature was detected only in patients with more severe progression of motor symptoms over 3 years, suggesting its potential as a predictor of disease severity. We validated this signature in independent PD cohorts and confirmed increased DNA damage in peripheral blood cells and dopamine neurons of the substantia nigra pars compacta in postmortem PD brains. Our study sheds light on an aging-related mechanism in PD pathogenesis and identifies potential markers of disease progression, providing a diagnostic platform to prognosticate disease progression.

Humans↗
PubMed1998

Naming in semantic dementia--what matters?

One of the major symptoms of semantic dementia (or progressive fluent aphasia) is profound word-finding difficulties. We present here a cross-sectional study of the factors affecting picture naming in semantic dementia based on data obtained from eight patients, together with a longitudinal analysis of naming in another patient. Various properties and attributes of the objects were entered into a series of regression analyses in order to predict which items the patients could or could not name. The analyses showed that object familiarity, word frequency and age-of-acquisition predicted naming success for the group and, in most cases, for each individual patient, irrespective of lesion site or overall naming success. We propose that the pattern of naming in semantic dementia is best described in terms of reduced semantic activation within a cascading/interactive speech production system. We suggest that object familiarity, and possibly word frequency, reflect the inherent robustness of individual semantic representations to the decay process in terms of both quantity and quality of experience. Age-of-acquisition and word frequency (at a phonological-lexical level) predicts naming success, because frequent, early-acquired words are relatively easy to activate even with reduced semantic "input".

Adult↗
PubMed1982

The effect of occupational exposure on pulmonary function: a longitudinal evaluation of fire fighters and nonfire fighters.

To examine the chronic effect of fire fighting on pulmonary function, we undertook a longitudinal analysis of 168 fire fighters and 1,474 nonfire fighters enrolled in a study of normal aging. Spirometric measurements (FVC and FEV1) were obtained on all subjects over a 5-yr intake period (1963 to 1968) and these subjects were reexamined 5 yr later (1968 to 1973). Questionnaire information about smoking habits, respiratory symptoms, and illness was also obtained. Fire fighters had a greater loss of pulmonary function (FVC and FEV1) than nonfire fighters (p = 0.007 and p = 0.054). This occupational effect could not be explained by differences in age, height, smoking status, or initial level of pulmonary function between the two occupational groups. Although respiratory symptoms were greater among current cigarette smokers, they were not significantly different between either occupational group. However, fire fighters generally reported more symptoms when smoking was controlled for. These results confirm earlier reports of a chronic effect of fire fighting on pulmonary function and suggest an association of this occupational with increased respiratory symptoms and disease independent of cigarette smoke.

Adult↗
PubMed1987

Longitudinal and secular trends in lipoprotein cholesterol measurements in a general population sample. The Framingham Offspring Study.

Two fasting lipoprotein cholesterol measurements have been made on Framingham Offspring Study participants, first in 1971-75 and again in 1979-83. Longitudinal analysis (n = 2433, age 20-49 at first exam) using multivariate regression found aging, weight gain, vasectomy, menopause, and increased smoking are associated with worsening lipoprotein profiles, while increased alcohol consumption is associated with increased high density lipoprotein cholesterol (HDL-C). Average increases in low density lipoprotein cholesterol (LDL-C) and very low density lipoprotein cholesterol (VLDL-C) in women accelerate with age; in men the increases are similar or perhaps decelerate with age. Secular trends were measured using age-adjusted mean values for individuals aged 25-54. Averages of total cholesterol, LDL-C (men only), systolic and diastolic blood pressure, body mass index, number of cigarettes per day, and alcohol consumption were lower at the second examination. Two secular trends in women indicate a possible worsening of population lipoprotein profiles: mean VLDL-C was higher and mean HDL-C lower at the second exam.

Adult↗
PubMed2003

Predictors of smoking initiation among college-bound high school students.

Smoking rates among college students is increasing, yet little is know about the development of students' smoking. This longitudinal analysis focuses on a national sample of high school students who were college students 4 years later (n = 1,479). SUDAAN statistical analysis procedures were used to weight and adjust for sampling design and nonresponse. Approximately 37% of the college students at follow-up who were never smokers at baseline had initiated smoking within the 4 years. Among experimenters at baseline, 25% had progressed their smoking behavior over the 4 years. Multivariate logistic regression analyses showed that there were different predictors of these two transitions among college students. Students who were more likely to initiate smoking were White, did not like school as much, and were more rebellious. Students who were more likely to progress from experimentation to a higher level of smoking thought peers approved of smoking and believed experimentation with smoking was safe. Several predictors of smoking initiation and progression during the transition from high school to college were identified that could be important components of interventions targeting high school and college-bound students. Increased efforts should be employed to include college students in national smoking prevention and cessation programs.

Adolescent↗
PubMed1999

Slow growth in the United States of the number of minorities in the RN workforce.

PURPOSE: To assess the extent to which the number of minority RNs has grown during the past 20 years, and to identify and compare key trends in personal and professional characteristics among minority groups and between minority and majority populations of RNs. Nursing education programs, employers, philanthropic organizations, and governments have expended considerable effort and resources to increase the number of minorities in nursing. DESIGN: Longitudinal analysis of trends in the number, education, employment, and earnings of minority RNs from 1977 to 1997. METHODS: Descriptive analysis of data from the U.S. National Sample Surveys of the Population of Registered Nurses, 1977-1996; and data from the U.S. Bureau of the Census Current Population Survey (CPS) Outgoing Rotation Group Annual Merged Files, 1977-1997. FINDINGS: In the past 20 years, the number of minority RNs has grown from 87,386 (or 6.3% of the total supply of RNs) in 1977 to 246,364 RNs (9.7%) in 1996. The number of Black (nonHispanic), Asian Pacific/Islanders, and American Indian/Alaskan Native nurses nearly tripled in this period while the number of Hispancis doubled. Although these rates of growth are impressive, the percentage of minorities in nursing lags considerably behind the percentage (18.3%) who are teachers, and the percentage (28.2%) in the U.S. population. CONCLUSIONS: Studies are needed to determine the barriers that exist in nursing education programs, health care organizations, and society in general that deter minorities from a nursing career. Without this understanding, efforts to design and implement ideas to attract, educate, and retain minorities in nursing education and later in the workplace are hampered.

Humans↗
PubMed2004

Social class, race/ethnicity and all-cause mortality in the US: longitudinal results from the 1986-1994 National Health Interview Survey.

BACKGROUND: Occupational social class has become a leading indicator of social inequalities in health. In the US, economic sectors are distinct with respect to wages, benefits, job security, promotion ladders and working conditions. The growing economic sector of self-employed workers is characterized by lower wages and benefits, and greater job insecurity. Little attention has been given to the association between economic sector measures of social class and all-cause mortality, and there have been no studies of mortality among the self-employed. METHODS: To determine risk of death associated with economic sector social class, this study entails a longitudinal analysis of the National Health Interview Survey (NHIS), an annual household survey representative of the US population for the period 1986-1994 (n = 377,129). The sample includes 201,566 men and 175,563 women, aged 24-65 years of age, in the civilian labor force. RESULTS: Non- professionals are at higher risk of death than professionals across all sectors and self-employed professionals are at higher risk of death than professionals employed in government and production. Additional social class differences are accounted for by age, race, gender and marital status. Results are also partially explained by income. After controlling for income, Black professionals did not show a lower risk of death than Black non-professionals and self-employed Hispanic professionals had a higher risk of death than Hispanic professionals employed in the private sector. CONCLUSIONS: Given the growth of self-employment in the US, the noted increased risk of death among self-employed professionals merits further investigation and monitoring.

Adult↗
PubMed2002

Behavioral change in persons with dementia: relationships with mental and physical health of caregivers.

The purpose of this study was to examine the effects that changes in behavioral and psychological symptoms of dementia of persons with Alzheimer's disease have on their caregivers' mental health and physical health. The research design was a prospective, longitudinal follow-up study conducted in a major medical center and in participants' homes. Longitudinal analysis linking change in behavior to caregiver outcomes was based on 64 cases. Care recipients were assessed at the time of diagnosis with the Mini-Mental State Examination (MMSE). To provide information on the care recipient's behaviors, caregivers participated in an interview with the Modified Neuropsychiatric Inventory at diagnosis and at follow-up. Caregivers also completed a battery of established instruments to measure stress appraisal, mental health, and perceptions of their physical health at follow-up. Results showed that increases in problem behaviors among persons living with dementia, along with residence status, were significant predictors of caregivers' mental health and also their physical health. However, these relationships were mediated through stress appraisal. Variables such as MMSE score of the person with dementia, number of years caregiving, relationship status, and education level were not significant predictors of caregivers' health when behavior change was in the model.

Adaptation, Psychological↗
PubMed1990

Juvenile delinquency and attention deficit disorder: boys' developmental trajectories from age 3 to age 15.

This article describes a longitudinal analysis of the behavior of a birth cohort of 435 boys. 4 groups were defined at age 13 on the basis of both self-reported delinquent behavior and professional diagnosis of Attention Deficit Disorder: ADD + delinquent, ADD only, delinquent only, and nondisordered. Biennial correlates of delinquency (antisocial behavior problems, verbal intelligence, reading difficulty, and family adversity) were traced across childhood. The ADD + delinquent boys consistently fared the worst on the assessments of family adversity, verbal intelligence, and reading. Their antisocial behavior began before school age, escalated at school entry, and persisted into adolescence. The ADD-only boys had normal family, intelligence, and reading scores, and showed only mild antisocial behavior in middle childhood. The delinquent-only boys showed no early risk from family, low intelligence, or reading deficit, and remained relatively free of conduct problems until they initiated delinquency at age 13. Persistence of criminal offending beyond adolescence is predicted for the ADD + delinquent boys.

Achievement↗
PubMedDate not supplied

Improving procedures for recording suicide statistics.

OBJECTIVE: To explore the changing relationship between rates of suicide and undetermined death in Britain and Ireland. DESIGN: Longitudinal analysis of the official statistics relating to unnatural deaths in England and Wales and the Republic of Ireland between 1976 and 1992. MAIN OUTCOME MEASURES: Male and female rates of suicide and undetermined deaths for Ireland and England and Wales, age adjusted to the standard world population. Ratio of undetermined deaths to suicide. RESULTS: The official Irish male suicide rate is now much higher than that of England and Wales while the female rates are broadly similar. The rate of undetermined deaths has risen amongst English males and remained stable for females but has significantly fallen off among both Irish males and females. The proportion of deaths classified as 'undetermined' is now very much less in Ireland than in England and Wales. DISCUSSION: National plans for suicide prevention in either country cannot be properly audited unless improved procedures are put in place to increase the validity and reliability of the official suicide figures. Each country could beneficially learn from the other in this regard.

Adolescent↗
PubMed2005

High myopia progression and visual impairment in a nonselected group of Danish 14-year-olds followed over 40 years.

PURPOSE: The purpose of this study was to document the adult age progression of myopia and the incidence of visual impairment in a representative sample of Danish adolescents with high myopia. METHODS: This study consisted of a scheduled regular ophthalmic follow-up over 40 years of 39 otherwise unselected Copenhagen 14 year olds with uni- and bilateral myopia of at least -6 D, as screened from a 1948 birth-year school cohort comprising 9243 pupils. Thirty-six of the 39 had satisfactory refractive and corrected visual acuity data for a longitudinal analysis. RESULTS: Myopia progression for the full period ranged from 0 to 14 D, and the peak myopia value increased from -14 to -26 D. The mean progression from age 16 to 26 years was 2.09 D, and from age 26 and on it was 1 D. Using both eyes and relevant correction, at the preliminary end point of 54 years, 32 of the 36 had a corrected visual acuity (VA) of 0.5 or better. Four had a corrected VA of < or = 0.3, but the visual loss was partly explained by other eye pathology. Significant visual reduction in single eyes mainly affected the subgroup of eyes with unilateral high myopia (n = 9). CONCLUSIONS: With only a slight overrisk recorded as associated with high myopia (in three or four of 36 subjects), the adult visual prognosis for working age appeared better than usually claimed. There seems to be a correlation between degree of myopia at age 14 and consecutive visual loss, but it was not possible to identify subjects at high risk at that early age.

Adolescent↗
PubMed2006

Hydrographics and the timing of infectious salmon anemia outbreaks among Atlantic salmon (Salmo salar L.) farms in the Quoddy region of Maine, USA and New Brunswick, Canada.

Infectious salmon anemia (ISA) has caused severe morbidity and mortality in farmed Atlantic salmon in North America, Norway, Scotland and the Faroe Islands. The Quoddy region of Maine, United States of America (USA), and New Brunswick (NB), Canada is characterized by extensive tidal mixing and close proximity between farms. This region is also prone to recurrent appearances of ISA, though control measures limit disease spread and severity on infected farms. We conducted a retrospective longitudinal analysis of the apparent impact of hydrographics on the incidence and timing of ISA outbreaks on Atlantic salmon (Salmo salar L.) farms in the Quoddy region from May 2002 to August 2004. A time-series cross-sectional regression of 32 farms over 28 months demonstrated a limited, but statistically significant, spatio-temporal clustering of ISA outbreaks linked hydrographically. New outbreaks correlated temporally with those occurring on-site 1 and 3 months prior, and those occurring within one tidal-excursion upstream the same month. Other risk factors included holdover of previous year-class fish, wharf sharing, and possibly harvests of cages infected in previous months. Conclusions suggest that tidal dispersion does play a role in ISAV transmission in the Quoddy region. Dispersal of free virus and/or tidal distribution of lice or other hydrographically influenced vectors or fomites could all contribute to the spatio-temporal patterns described.

Animals↗
PubMed2003

Progression of HIV disease among women following delivery.

OBJECTIVE: To assess patterns of HIV disease progression among HIV-1-infected women following delivery. METHODS: Four hundred ninety-seven women enrolled in PACTG 185, a phase 3 trial of passive immunoprophylaxis in addition to zidovudine (ZDV) for the prevention of perinatal transmission, were included. Visits occurred twice during pregnancy; at delivery; and at 12, 26, 48, and 78 weeks postpartum. Repeated-measures linear regression and proportional hazards models were applied. RESULTS: Trial treatment (HIV hyperimmune globulin vs. immune globulin) was not related to postpartum disease progression. Longitudinal analysis of HIV-1 RNA demonstrated stable levels during pregnancy, significantly increased HIV-1 RNA by 12 weeks postpartum even on stable therapy, and a gradual increase thereafter. Changes in CD4+ lymphocyte percentage over 18 months of follow-up were similar for women continuing or stopping ZDV postpartum. Compared with those receiving no therapy, the hazard ratio for AIDS or death among women who received monotherapy postpartum was 0.52 (95% confidence interval [CI]: 0.25-1.04), 0.17 (CI: 0.06-0.49) for women who received combination therapy, and 0.24 (CI: 0.06-1.01) for women who received highly active antiretroviral therapy. CONCLUSIONS: RNA levels increased significantly from delivery to 12 weeks postpartum. Changes in HIV-1 RNA and CD4+ lymphocyte percentage were similar among women continuing or stopping therapy after delivery, and response to antiretroviral therapy was as expected postpartum.

Adult↗
PubMed2003

Progressive reversion of human immunodeficiency virus type 1 resistance mutations in vivo after transmission of a multiply drug-resistant virus.

Evolution and transmission of multiply drug-resistant human immunodeficiency virus type 1 (HIV-1) may limit therapeutic options as global treatment efforts expand. However, the stability of these mutants in the absence of drug selection pressure is not known. We performed a longitudinal analysis of plasma virus from a person who acquired HIV-1 that contained multiple reverse transcriptase (RT) and protease (PR) mutations. In the absence of therapy, 5 of 12 drug resistance mutations reverted in a stepwise fashion to wild type over the course of 52 weeks. Reversion of the M184V mutation alone did not change viral replicative capacity (RC), but it led to enhanced resistance to zidovudine and tenofovir. However, reversions of a second RT mutation and 3 PR mutations were associated with an increase in viral RC, and this was temporally correlated with a marked decrease in CD4 cell number. This study demonstrates the gradual stepwise back-mutation of certain drug resistance mutations in vivo in the absence of ongoing drug selection pressure. Moreover, it suggests that, despite initially impaired viral fitness, a transmitted HIV-1 isolate with multiple drug resistance mutations can evolve to develop increased RC and significant pathogenicity.

Adult↗
PubMed2002

Utilization of psychotropic drugs in Taiwan: an overview of outpatient sector in 2000.

BACKGROUND: Development of pharmacological treatment in mental disorders has risen drastically over the past decade in Taiwan. We performed a survey of the National Health Insurance claims for outpatient psychiatric services to study the utilization of psychotropic drugs. The analysis followed the drug classification and standardized measurements proposed by the World Health Organization. METHODS: The sampling datasets from the National Health Insurance Research Database served as data sources. They represented 0.2% of the entire claims for outpatient medical services in 2000. The measurement units used for psychotropic drugs were either prescription volumes (drug items) or the number of defined daily doses (DDDs). To estimate the proportion of the population treated daily with psychotropic drugs, numbers of DDDs per 1000 inhabitants per day were also calculated. Beside overall description, the data of psychotropic substance prescriptions were analyzed by stratifying patient's age, physician's specialty, accreditation status of hospital, and chemical subgroup of psychotropic drugs. RESULTS: Prescription of psychotropic drug items (n = 63,539) was 3.24% of the total drug items (n = 1,958,820) claimed. The psychotropic drugs were prescribed to 9.2% of the total patients and in 9% of the total visits. Major consumers of psychotropic drugs were between 35-74 years of age and there were more women than men. The psychiatrist was the largest group of physicians who had prescribed psychotropic drugs and contributed 18.5% of all drug items and 38.3% of total DDDs of psychotropic drugs. The number of DDDs per 1000 inhabitants per day for all kinds of psychotropic drugs was estimated to be 32.94 in Taiwan, where anxiolytics accounted 14.30, hypnotics and sedatives 10.64, antipsychotics 3.41, antidepressants 3.06 and mood stabilizers 1.43. Ordered by total DDDs, the top 10 most frequently used chemical substances were flunitrazepam, alprazolam, fludiazepam, oxazolam, lorazepam, diazepam, zolpidem, estazolam, zopiclone, and haloperidol. CONCLUSIONS: The usage level of psychotropic drugs in Taiwan was lower than in most industrialized countries, especially for antidepressants. The future goals are to focus on the longitudinal analysis of general trend for each psychotropic substance and to associate the pharmacoepidemiological data in parallel with the upcoming epidemiological study of mental disorders in Taiwan.

Adolescent↗
PubMed1978

Does help help? The adaptive consequences of obtaining help from professionals and social networks.

This study reports on a longitudinal analysis of changes in adaptation associated with seeking help on a representative sample of Chicago area adults who had experienced one of three transitions or four crises during the interval between 1972 and follow-up 1976--77 interviews. For each event, respondents are classified into three groups according to their help-seeking behavior: those who went to professionals, those who went only to their social networks, and those who had the event but sought no help. Nine measures of adaptation are used: symptoms of anxiety and depression and strains and stresses in four role areas. Statistical controls equate the groups on demographic characteristics, perceived stress, personal resources, access to help, and elapsed time since the event. There are no consistent statistical significant differences among the groups. No evidence is found that help-seeking has positive adaptive consequences. The findings are not likely to result from an inadequate sample, outcome measures, or statistical controls, but could result from insufficient information on the kind, quality, and duration of the help provided.

Adaptation, Psychological↗
PubMed2002

Predicting incarceration of clients of a psychiatric probation and parole service.

OBJECTIVE: This study assessed the extent to which clinical characteristics, psychiatric status, and use of mental health services explain incarceration for technical violations of probation or parole rather than incarceration for new offenses. METHODS: A total of 250 clients of an urban psychiatric probation and parole service were screened for psychiatric diagnoses and monitored with a 12-month data collection protocol. Longitudinal analysis was used to explain incarceration on new charges, incarceration on technical violations of probation and parole, or absence of incarceration. RESULTS: Eighty-five individuals (34 percent) were incarcerated during the follow-up period. Forty-four (18 percent) were incarcerated for a new offense, and 41 (16 percent) were incarcerated for a technical violation. Participation in mental health treatment was associated with a lower risk of incarceration for a technical violation. Intensive monitoring by mental health providers, such as through case management and medication management, were significant risk factors for incarceration for a technical violation. Clients who were incarcerated for a technical violation were more than six times as likely to have received intensive case management services. CONCLUSIONS: The role of mental health services in reducing the risk of incarceration remains mixed. Providing services that emphasize monitoring tends to increase the risk of incarceration for technical violations of criminal justice sanctions. However, any participation in treatment and motivation to participate in treatment appears to reduce the risk of incarceration.

Adult↗