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PubMed2005

Reconstitution of EBV latent but not lytic antigen-specific CD4+ and CD8+ T cells after HIV treatment with highly active antiretroviral therapy.

The incidence of (EBV-related) malignancies in HIV-infected subjects has declined since the introduction of highly active antiretroviral therapy (HAART). To investigate the effect of HAART on EBV infection, we performed a longitudinal analysis of the T cell response to both a latent and a lytic Ag and EBV viral load in 10 subjects from early in HIV infection up to 5 years after HAART. All individuals responded to HAART by a decline in HIV viral load, a restoration of total CD4+ T cell numbers, and a decline in T cell immune activation. Despite this, EBV load remained unaltered, even after 5 years of therapy, although a decline in both CD4+ and CD8+ T cells specific for the lytic EBV protein BZLF1 suggested a decreased EBV reactivation rate. In contrast, latent EBV Ag EBNA1-specific CD4+ and CD8+ T cell responses were restored after 5 years of treatment to levels comparable to healthy individuals. In two individuals who were treated by HAART late during HIV progression, a lymphoma developed shortly after initiation of HAART, despite restoration of EBV-specific CD4+ and CD8+ T cells. In conclusion, long-term HAART does not alter the EBV DNA load, but does lead to a restoration of EBNA1-specific T cell responses, which might allow better control of EBV-infected cells when applied early enough during HIV infection.

Adult↗
PubMed1999

Drug abuse-related mortality: a study of teenage addicts over a 20-year period.

BACKGROUND: There is growing concern about increase in illicit drug use and associated fatalities in young people. METHOD: This longitudinal analysis of successive cohorts of addicts in England and Wales aged 15-19 years followed up over a 20-year period covering 1974 to 1993 (1) investigated trends in all-causes mortality; (2) examined teenage-specific mortality, i.e. deaths during ages 15-19 years; (3) determined excess teenage-specific mortality; and (4) identified the main underlying causes of teenage-specific death in this population. The main outcome measures were overall mortality rates, teenage-specific mortality and standardised mortality ratios calculated for four 5-year (period) successive cohorts. RESULTS: Overall mortality rate in the study population (N = 9491) was 4.7/1000 person-years. The median age at death was 23 years (semi interquartile range = 3), with the majority (91.3%) of deaths occurring between ages 15 and 29 years. Excess teenage-specific mortality in the population was 10.7 in males and 21.2 in females (general population = 1), and increase in excess mortality in both sexes was evident in the last 5-year period of study. The majority of deaths (64.3%) resulted from accidental poisoning. Methadone and heroine/morphine accounted for about two-thirds of accidental poisoning deaths, while suicide accounted for 11.4% of teenage-specific deaths. CONCLUSIONS: It is strongly recommended that treatment services should be more responsive to the need for careful prescribing, dispensing and administration of substitute medication to teenage addicts in their care. The development of needs-led, case-sensitive treatment services for young addicts is indicated.

Adolescent↗
PubMed2006

The effect of recurrent involuntary job loss on the depressive symptoms of older US workers.

OBJECTIVES: The objective of this study was to assess whether recurrent involuntary job loss among US workers nearing retirement resulted in increasingly less severe changes in depressive symptoms with successive job losses. METHODS: With data drawn from the US Health and Retirement Survey (HRS), we used repeated measures longitudinal analysis to investigate the effect of recurrent job loss on follow-up depressive symptoms, measured up to 2 years following job loss. Study participants include 617 individuals, aged 51-61 years at the 1992 study baseline, who had at least one job loss between 1990 and 2000. Our primary outcome variable was a continuous measure of depressive symptoms, constructed from the 8-item Center for Epidemiologic Studies-Depression (CES-D) battery administered at every HRS wave. A second, dichotomous outcome, derived from the continuous measure, measured clinically relevant depressive symptoms. The exposure (recurrent job loss) was defined by binary dummy variables representing two and three/four job losses. All job losses were the result of either plant closing or layoff. RESULTS: Our main finding indicates that, after relevant covariates are controlled, compared to one job loss, two job losses result in a modest increase in the level depressive symptoms (not significant) at two-year follow-up. Three or more job losses result, on average, in a decline in depressive symptoms to a level near pre-displacement assessment (not significant). Somewhat in contrast, two job losses were found to be associated with increased risk of clinically relevant depressive symptoms. CONCLUSIONS: The principal finding confirms our hypothesis that, among US workers nearing retirement, repeated exposure to job separation results in diminished effects on mental health. Adaptation to the job loss stressor may underlie the observed response, although other explanations, including macroeconomic developments, are possible.

Adaptation, Physiological↗
PubMed2002

Effects of cognitive performance on change in physical function in long-stay nursing home residents.

BACKGROUND: Determining the nature and rate of change in physical function among long-stay nursing home (NH) residents classified by cognitive performance is needed to inform judgments about prognosis and design of clinical trials to minimize functional decline. METHODS: The study consisted of a longitudinal analysis using random coefficients models of 71,388 noncomatose residents aged 65 and older admitted in one of five states participating in the Health Care Financing Administration-sponsored National Case Mix and Quality Demonstration Project who stayed in the nursing home 1 year or longer. Linear effects of cognitive impairment on admission and over time on the trajectory of dependence in activities of daily living (ADLs) were estimated, adjusting for demographic status upon admission. Interaction terms were used to determine if subgroups of residents at the same cognitive level were at risk for a steeper than average rate of decline. Measures were derived from the NH Minimum Data Set (MDS+) ratings of each domain. Cognition was measured using the MDS-Cognitive Performance Scale. Physical function was determined by summing ADL dependence ratings of bathing, dressing, grooming, toileting, and eating (range 0 to 20). Demographics included age, gender, race, and marital status. RESULTS: On average, ADL dependence worsened 0.84 points per year among these long-stay residents. Only cognition and marital status had clinically significant effects on ADL dependence. Married residents exhibited more ADL dependence than unmarried residents. Severity of cognitive impairment on admission and over time influenced severity of ADL dependence but not rate of decline. No interaction terms were clinically significant. CONCLUSIONS: Clinicians seeking to identify factors that accelerate ADL decline in long-stay NH residents must examine explanatory variables other than cognitive impairment and demographics.

Activities of Daily Living↗
PubMed2006

Association of testosterone and estradiol deficiency with osteoporosis and rapid bone loss in older men.

CONTEXT: The clinical value of measuring testosterone and estradiol in older men with osteoporosis and of measuring bone mineral density (BMD) in older men with testosterone or estradiol deficiency is uncertain. OBJECTIVE: The objective of the study was to examine the association of testosterone and estradiol deficiency with osteoporosis and rapid bone loss in older men. DESIGN: This study was a cross-sectional and longitudinal analysis. SETTING: The study was conducted at six U.S. centers of the Osteoporotic Fractures in Men study. PARTICIPANTS: The study population consisted of 2447 community-dwelling men aged 65 yr or older. MAIN OUTCOME MEASURES: Total testosterone deficiency was defined as less than 200 ng/dl. Total estradiol deficiency was defined as less than 10 pg/ml. Osteoporosis was defined as femoral neck or total hip BMD T-score of -2.5 or less. Rapid bone loss was defined as 3%/yr or more. RESULTS: Prevalence of osteoporosis in men with deficient and normal total testosterone was 12.3 and 6.0% (P = 0.003) and 15.4 and 2.8% (P < 0.0001) in those with deficient and normal total estradiol. Among osteoporotic men and those with normal BMD, prevalence of total testosterone deficiency was 6.9 and 3.2% (P = 0.01), and prevalence of total estradiol deficiency was 9.2 and 2.4% (P = 0.0001). Incidence of rapid hip bone loss in men with deficient and normal total testosterone was 22.5 and 8.6% (p = 0.007) and in those with deficient and normal total estradiol was 14.3 and 6.3% (p = 0.08). CONCLUSIONS: Older men with total testosterone or estradiol deficiency were more likely to be osteoporotic. Those with osteoporosis were more likely to be total testosterone or estradiol deficient. Rapid hip bone loss was more likely in men with total testosterone deficiency. BMD testing of older men with sex steroid deficiency may be clinically warranted.

Aged↗
PubMed2005

Effects of changes in self-reported vision on cognitive, affective, and functional status and living arrangements among the elderly.

PURPOSE: To study effects of changes in self-reported vision on functional status, cognition, depressive symptoms, and living arrangements. DESIGN: Longitudinal analysis of household survey data. METHODS: A total of 6234 sample persons observed in the study of Assets and Health Dynamics Among the Oldest Old (AHEAD) 1995 were followed in 1998, 2000, and 2002 or until death or sample attrition. Effects of changes in self-reported vision and other factors were assessed by means of ordinary least-squares and logistic regression with panel data methods. Main outcome measures were limitations of instrumental activities of daily living (IADLs), activities of daily living (ADLs), and other, cognition, depressive symptoms, and living arrangements. RESULTS: A decline from excellent/good vision to fair/poor near and distance vision had statistically significant effects on several IADL limitations, and some ADL and other limitations. Largest effects were for driving (OR for no limitation: 0.55, P = .003), managing money (OR: 0.61, P < .001), and preparing hot meals (OR: 0.61, P < .001). Onset of fair-poor near vision increased the likelihood of onset of at least one IADL (OR for no limitation: 0.71, P < .01) and ADL (OR: 0.74, P = .003) limitation. Onset of legal blindness resulted in a 78% increase in the likelihood of an IADL limitation (OR for no limitation: 0.22, P < .001). Effects of vision declines on cognition and depressive symptoms were statistically significant but small. Decline in vision increased the probability of nursing home residence. CONCLUSIONS: Visual impairment has major impacts on functional status. Preventing vision loss is likely to appreciably improve the functioning of elderly persons.

Activities of Daily Living↗
PubMed2003

Pubertal course of persistently short children born small for gestational age (SGA) compared with idiopathic short children born appropriate for gestational age (AGA).

OBJECTIVE: Few data are available on the pubertal development of children born small for gestational age (SGA) who fail to show catch-up growth. DESIGN: A longitudinal analysis compared the pubertal course of persistently short children born SGA compared to children with idiopathic short stature who were appropriate for gestational age (AGA). One hundred and twenty-eight short children (height SDS<-1.7), including 76 (31 boys) born SGA and 52 (22 boys) born AGA, were regularly followed from early childhood to completion of puberty. RESULTS: Puberty was attained at normal age (10.5-14 Years in boys, 9.5-13 Years in girls) for most children in both the SGA and AGA groups (boys, 80% and 77%; girls, 76% and 78% respectively). The duration of puberty was similar in the SGA and AGA groups. Menarche occurred at normal age range but was significantly earlier in the SGA girls (P<0.01 by ANOVA). Despite the similar total pubertal growth, the patterns of growth differed significantly: SGA group - accelerated growth and bone maturation rates from onset of puberty with peak height velocity at Tanner stages 2-3, followed by a decelerated growth rate and earlier fusion of the epiphyses; AGA group - steady progression of bone elongation and maturation throughout puberty (pubertal growth, P<0.05 in both sexes; bone maturation, P<0.001 in both sexes). Final height in the SGA group was compromised compared with their target height (P<0.001). CONCLUSION: Children born SGA have a normal pubertal course with a distinct pubertal growth pattern. This pattern may represent an altered regulation of their growth modalities.

Adolescent↗
PubMed1996

Long-term stability of Class II furcation defects treated with barrier membranes.

The present longitudinal study was designed to explore the long-term efficacy of guided tissue regeneration (GTR) in Class II furcation defects and establish the factors that might be responsible for modifying this response. Subjects with two or more mandibular molars, one of which had Class II furcation defects, received the hygienic phase of therapy followed by baseline clinical measurements and subgingival plaque sampling. GTR procedure was performed in furcation defect sites using expanded polytetrafluoroethylene (ePTFE) membranes, while the other non-furcated molars received only scaling and root planning. Twenty-eight subjects (13 females, 15 males) aged 27 to 66 were included in this longitudinal analysis. Post-surgical treatment included routine home care supplemented with daily chlohexidine rinse and systemic tetracycline. Membranes were retrieved 4 to 6 weeks after surgery. During the first year, patients were initially seen bi-weekly and subsequently monthly for professional prophylaxis. At the end of this year, clinical measurements and samples were obtained. For the next 2 years, patients were seen bi-annually for maintenance visits. Clinical measurements and microbiological samples were then repeated. Next, a tighter maintenance protocol was established and patients were seen quarterly for scaling and oral hygiene reinforcement. Final measurements and samples were taken again 1 year later (4 years postoperative). Significant probing reduction (3.00 mm) and gain in horizontal attachment (2.59 mm) were obtained 1 year postsurgery for the GTR sites. These changes were maintained over 4 years with a slight decline at the end of year 3. Changes in probing depth (PD) from year 1 to 4 served to dichotomize the sites into stable (delta PD < or = 0.9 mm), and unstable (PD increase > or = 1 mm). Of the 54 sites available for this analysis only 5 (9.3%) were unstable while 49 (90.7%) were stable or even further improved. Sites which exhibited minimal or no plaque (plaque index [PI] < or = 1) over the tight maintenance period had a further decrease in mean probing depth (0.43 mm) compared with a slight increase (-0.06 mm) in mean probing depth in sites with PI > or = 2 mm (P = 0.0235). The same phenomenon was observed for changes in relative attachment level (RAL): mean gain in RAL was 0.61 mm compared to 0.25 mm for the 2 groups, respectively (P = 0.07). Actinobacillus actinomycetemcomitans was only isolated from 2 sites at year 3, and none at year 4, compared to 21.45% of the sites at baseline. Porphyromonas gingivalis positive sites showed a continual decline over the years: 14.28% at baseline, 10.71% at year 1, and 5.1% at year 4. On the contrary, Prevotella intermedia (Pi) and Bacteroides forsythus (Bf) infected sites remained at approximately the same rate throughout the 4 years of the study (40% to 50% and 30% to 40% for Pi and Bf, respectively). Of these, Pi-infected sites exhibited less favorable clinical results compared to sites which were not infected with this microorganism. In summary, furcation defects treated with membrane barriers can be maintained in health for at least 4 years; however, good oral hygiene and frequent recall visits as part of a complete anti-infective therapy are essential. Finally, once treated, these teeth are comparable to similar molar teeth with no previous history of furcation pathosis.

Adult↗
PubMed2005

Predictive modeling of total healthcare costs using pharmacy claims data: a comparison of alternative econometric cost modeling techniques.

OBJECTIVE: We sought to evaluate several statistical modeling approaches in predicting prospective total annual health costs (medical plus pharmacy) of health plan participants using Pharmacy Health Dimensions (PHD), a pharmacy claims-based risk index. METHODS: We undertook a 2-year (baseline year/follow-up year) longitudinal analysis of integrated medical and pharmacy claims. Included were plan participants younger than 65 years of age with continuous medical and pharmacy coverage (n = 344,832). PHD drug categories, age, gender, and pharmacy costs were derived across the baseline year. Annual total health costs were calculated for each plan participant in follow-up year. Models examined included ordinary least squares (OLS) regression, log-transformed OLS regression with smearing estimator, and 3 two-part models using OLS regression, log-OLS regression with smearing estimator, and generalized linear modeling (GLM), respectively. A 10% random sample was withheld for model validation, which was assessed via adjusted r, mean absolute prediction error, specificity, and positive predictive value. RESULTS: Most PHD drug categories were significant independent predictors of total costs. Among models tested, the OLS model had the lowest mean absolute prediction error and highest adjusted r. The log-OLS and 2-part log-OLS models did not predict costs accurately as the result of issues of log-scale heteroscedasticity. The 2-part model using GLM had lower adjusted r but similar performance in other assessment measures compared with the OLS or 2-part OLS models. CONCLUSION: The PHD system derived solely from pharmacy claims data can be used to predict future total health costs. Using PHD with a simple OLS model may provide similar predictive accuracy in comparison to more advanced econometric models.

Adolescent↗
PubMed2006

Identification of women at risk of adverse weight development following pregnancy.

BACKGROUND: It has been known for long time that pregnancy associated with weight problems women but few important factors have been identified, except for weight gain during pregnancy itself. OBJECTIVE: To identify cutoffs for weight gain during pregnancy for identification of women at risk of high weight retention after pregnancy. METHODS: A longitudinal analysis of 563 women who gave birth in 1984-1985 was used. Weight development during pregnancy was used as diagnostic test for high weight retention at 1 and 15 years follow-up. True positives for high weight retention were defined as > 90th percentile at 1 and 15 years. Receiver Operating Characteristic (ROC) analyses were performed to derive cutoffs minimizing the absolute and relative number of misclassifications. RESULTS: The average weight retention at 1 year (WR1y) and 15 years (WR15y) was 1.1 +/- 3.6 and 7.6 +/- 7.4, respectively. There was a moderately strong correlation between weight gain during pregnancy and weight retention at 1 and 15 years follow-up (r2 = 0.13 and r2 = 0.05, respectively; both P < 0.001) and weight gain during pregnancy as diagnostic test to find high weight retainers performed better than chance both for WR1y (AUC = 0.76 +/- 0.04, P < 0.01) and WR15y (0.63 +/- 0.04, P < 0.05). To minimize the absolute number of misclassifications of high weight retention, a highly specific and insensitive cut-off of around 24 kg weight gain during pregnancy was needed. The best trade-off between sensitivity and specifity, minimizing the relative number of misclassifications, was at a cutoff of around 16 kg, but this resulted in three times as many absolute misclassifications. CONCLUSION: Weight gain during pregnancy was found to be a moderately strong diagnostic test for weight retention after pregnancy. In order to implement weight gain recommendations for clinical practice larger studies need to be conducted and the demands on the reference values specified, since decisions about the trade-offs between types and extent of misclassifications need to be made.

Adult↗
PubMed1994

Hepatitis C virus infection in healthcare workers: risk of exposure and infection.

OBJECTIVES: To determine the incidence of hepatitis C virus (HCV) infection among healthcare workers (HCWs) at a university hospital, the proportion of HCWs having non-A, non-B hepatitis (NANBH) who were anti-HCV positive, and the rate of HCV transmission following a HCV-positive needlestick injury. DESIGN: Longitudinal analysis of a dynamic (cohort) population. MEASUREMENTS: From 1980 through 1989, HCWs who had clinical NANBH were identified, and from 1987 through 1989, HCWs who reported a blood or body fluid exposure and the patients who were the source of the exposure were screened for antibodies to HCV. SETTING: A 732-bed, university hospital and outpatient clinics. RESULTS: Over the 10-year period, six cases of occupationally acquired NANBH were observed, for an incidence of 21 cases per 100,000 HCWs per year (standardized incidence ratio, 2.96; 95% confidence interval [CI95], 1.83 to 4.36). Four of the six cases were confirmed to be HCV infection. From 1987 through 1989, 176 (12.7%) of 1,387 patients who were the source of an exposure were anti-HCV positive. Exposures that occurred in the emergency department were more likely to be anti-HCV positive than were exposures from all other locations (relative risk [RR] = 1.7; P = 0.009). Of HCWs who had an HCV-positive needlestick injury and whose serum had been tested for anti-HCV at least 5 months after the exposure, 3 (6.0%) of 50 seroconverted. From 1987 through 1989, the incidence of HCV infection among HCWs was 54 cases per 100,000 HCWs per year. CONCLUSION: The incidence of clinical NANBH among HCWs in this study is approximately three times higher than that of non-HCWs. HCWs are at significant risk for exposure to and acquisition of HCV.

Adult↗
PubMed2006

Incidence of cervical cytological abnormalities with aging in the women's health initiative: a randomized controlled trial.

OBJECTIVE: To estimate the incidence of cytological abnormalities and cervical cancer and to determine the effect of oral estrogen and progestin on cervical cytology among postmenopausal women participating in a multi-institution clinical trial. METHODS: The study was a longitudinal analysis of a prospective cohort of 16,608 postmenopausal women (aged 50-79 years) participating in the Women's Health Initiative (WHI) clinical trial of estrogen plus progestin. Eligible participants had a cervical smear within 1 year before randomization and at 3- and 6-year follow-ups. Outcomes measured were low-grade and high-grade squamous intraepithelial lesions (LSIL, HSIL) and cervical cancer at follow-up years 3 and 6. RESULTS: Of 15,733 eligible participants with a uterus, 7,663 were assigned to placebo and 8,070 to estrogen plus progestin. At baseline, 318 women (2%) had low-grade abnormalities on cervical cytology. The annual incidence rate of any new cytological abnormality in the estrogen plus progestin group was significantly higher than that in the placebo group (hazard ratio 1.4, 95% confidence interval [CI] 1.2-1.6). Independent risk factors for HSIL and cervical cancer over a 6-year follow-up (after stratifying for baseline cytologic abnormalities) included sexual activity in the past year while not being married or living as married (hazard ratio 3.5, 95% CI 1.5-8.3). Risk factors did not include age or use of estrogen plus progestin. CONCLUSION: Use of estrogen plus progestin was associated with increased incidence of any cytologic abnormality, although it had no impact on the incidence of HSIL or cervical cancer. Sexually active older women who are not married or living as married may benefit from continued cervical cancer screening. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov, www.clinicaltrials.gov, NCT00000611.

Aged↗
PubMed2006

Further dental treatment needs of children receiving exodontia under general anaesthesia at a teaching hospital in the UK.

OBJECTIVES: The aim of this study was to investigate the subsequent dental treatment needs of children who had dental extractions under general anaesthesia (GA) in 1997 in the Day Case Unit at Leeds Dental Institute (LDI), Leeds, UK, and the reasons for repeat dental GAs (DGAs). STUDY DESIGN: The authors conducted a retrospective longitudinal analysis. SUBJECTS AND METHODS: Information collected from hospital records for the 6-year period following the first DGA included: reasons for the DGA in 1997 and teeth extracted; the number of subsequent DGAs, reasons and treatment; incidents of and reasons for toothache or swelling after 1997; treatment under local anaesthesia (LA) or inhalation sedation (IS) at LDI during the 6 years following the DGA in 1997. RESULTS: The study population consisted of 484 children, who received GA exodontia at LDI with a mean age of 6.35 years [95% confidence interval (CI) = 6.1, 6.6] and age range of 1-16 years. The most common reason for extractions at the original DGA in 1997 was dental caries, and the mean number of extractions was 4.24 (95% CI = 4.05, 4.43). Primary teeth extractions accounted for 82% of the cases. In total, 143 children (27.5%) had a record of follow-up treatment at LDI. Of these children, 32% had treatment under LA, 7% under LA and IS, and 15% received preventive care only. The overall repeat rate for DGA was 10.7%, with caries (84%) being the main reason for this. Of the teeth subsequently extracted, 72% were recorded as caries-free or unerupted at the time of the DGA in 1997. CONCLUSIONS: A large proportion of the follow-up visits were to treat newly developed dental disease during the 6 years following the DGA in 1997. A more proactive approach towards preventive care may have resulted in the reduction of the development of new dental disease.

Adolescent↗
PubMed2004

Reducing drinking and related harms in college: evaluation of the "A Matter of Degree" program.

OBJECTIVES: To examine the effects of a multisite environmental prevention initiative, the "A Matter of Degree" (AMOD) program, on student heavy alcohol consumption and resultant harms at ten colleges. METHODS: A quasi-experimental longitudinal analysis of alcohol consumption and harms was employed, using repeated cross-sectional survey data from the Harvard School of Public Health College Alcohol Study (CAS). Areas examined included seven measures of alcohol consumption, thirteen measures of alcohol-related harms, and eight measures of secondhand effects of alcohol use by others. Comparisons were conducted on self-reported behavior of students for the ten AMOD sites in aggregate and by level of program implementation, with students at 32 comparison colleges in the CAS, for each outcome. RESULTS: No statistically significant change was found in the overall ten-school AMOD program for outcome measures of interest from baseline (1997) to follow-up (2001). However, there was variation in the degree of environmental program development within AMOD during the intervention period. A pattern of statistically significant decreases in alcohol consumption, alcohol-related harms, and secondhand effects was observed, reflecting minor to more substantial changes across measures among students at the five program colleges that most closely implemented the AMOD model of environmental change. No similar pattern was observed for the low implementation sites or at 32 comparison colleges. CONCLUSIONS: While there was no change in the ten AMOD schools in study measures, significant although small improvements in alcohol consumption and related harms at colleges were observed among students at the five AMOD sites that most closely implemented the environmental model. Fidelity to a program model conceptualized around changing alcohol-related policies, marketing, and promotions may reduce college student alcohol consumption and related harms. Further research is needed over the full course of the AMOD program to identify critical intervention components and elucidate pathways by which effects are realized.

Alcohol Drinking↗
PubMed1999

Hormone replacement therapy: patterns of use studied through British general practice computerized records.

OBJECTIVE: We aimed to describe the longitudinal pattern of hormone replacement therapy (HRT) consumption in a cohort of long-term users (defined as use for >1 year). METHOD: We carried out longitudinal analysis of prescription data derived from GPs' computer records. Subjects were recruited through 15 general practices in the former Oxford, South West and North West Thames Regions that contributed to the VAMP/OPCS general practice research database. All women in the practices aged 45-64 years in September 1991 were identified. Of these, the analysis concerned the 1224 long-term users and 1154 non-user controls who remained in the practices from September 1991 to March 1995; 868 (71%) of the users and 698 (61%) of the controls also provided questionnaire data. RESULTS: The prevalence of HRT use was 15% in 1992, a rise of 16% from 1991. The prevalence of long-term use was 10%; 22% of the cohort identified as taking HRT between April and September 1991 had left the practices or were not taking HRT 1 year later. But for the group defined as long-term users in 1992, the rate of discontinuation was less than 5% per year over the following 2 1/2 years. Users of opposed therapy were 50% more likely to discontinue than users of unopposed therapy. Almost all women who had or had not undergone hysterectomy were taking unopposed or opposed therapy, respectively. Over 80% of prescriptions were for oral therapy. A third of users of either opposed or unopposed therapy changed the formulation during the 4 years of observation, and two-thirds of those who used both forms changed at least once in addition. Two changes were required to accommodate 94% of users. CONCLUSIONS: Once women have taken HRT for a year, their continuation rate is over 95% per annum. Although the majority of women stayed with one formulation, a substantial minority changed formulation quite frequently, three formulations being required to accommodate 94% of long-term users over 4 years. Any trial of HRT use will need to recruit long-term users and allow for change in formulation of HRT in its protocol.

Aged↗
PubMed2001

The presence of hepatitis B surface antigen and deoxyribonucleic acid in amniotic fluid and cord blood.

OBJECTIVE: It is uncertain whether neonatal infection with hepatitis B, despite treatment after delivery with immunoglobulin and vaccine, is the result of prior in utero transmission of the virus or treatment failure. Furthermore, the potential risk of hepatitis B transmission from the mother to the fetus at the time a genetic amniocentesis is performed is also a concern. In an attempt to better elucidate these controversies, amniotic fluid and cord blood specimens obtained from pregnant women positive for hepatitis B surface antigen were analyzed for the presence of hepatitis B surface antigen and hepatitis B deoxyribonucleic acid. STUDY DESIGN: This study was a prospective longitudinal analysis that identified hepatitis B surface antigen-positive patients who presented for amniocentesis. Cord blood was obtained from these patients at the time of delivery. Cord blood was also obtained from a group of hepatitis B surface antigen-positive patients for whom no amniocentesis was performed. All samples were analyzed for the presence of hepatitis B surface antigen and hepatitis B deoxyribonucleic acid. RESULTS: A total of 121 hepatitis B surface antigen-positive pregnant women were identified. In the 72 pregnancies in which amniocentesis was not performed, 18% of the cord blood samples were positive for hepatitis B surface antigen and 4% were positive for hepatitis B deoxyribonucleic acid. Of 47 amniocentesis fluid samples, 32% were positive for hepatitis B surface antigen but all were negative for hepatitis B virus deoxyribonucleic acid. Of 30 cord blood samples from patients who underwent an amniocentesis, 27% were positive for hepatitis B surface antigen, but all were negative for hepatitis B virus deoxyribonucleic acid. CONCLUSIONS: This study found that hepatitis B viral deoxyribonucleic acid is rarely present in cord blood and was not identified in amniotic fluid obtained by amniocentesis. This finding suggests that in utero transmission of the virus is rare prior to the onset of labor. These data further confirm the reports in the current literature that the risk of hepatitis B transmission to the fetus during amniocentesis is low. Because hepatitis B surface antigen can exist as an isolated entity devoid of nuclear material, in some cases this protein may be able to traverse the placental and amniotic membrane barrier in a manner similar to other proteins, such as alpha-fetoprotein. Recommendations for genetic amniocentesis in women positive for hepatitis B surface antigen are discussed.

Amniocentesis↗
PubMed1993

Anterior transposition of the inferior oblique muscle for dissociated vertical deviation.

BACKGROUND: Recently, anterior transposition of the inferior oblique muscle was reported to be an effective treatment for dissociated vertical deviation (DVD), but data on long-term stability have not been reported. METHODS: A retrospective, longitudinal analysis of 17 consecutive patients (22 eyes) with dissociated vertical deviation and inferior oblique overaction who had an anterior transposition of the inferior oblique for significant dissociated vertical deviation and a minimum of 12 months postoperative follow-up was undertaken. The size and degree of control of the dissociated vertical deviation and the degree of inferior oblique overaction were assessed preoperatively, and postoperatively at 1 week, at 4 to 6 months, and when last seen. The frequency of postoperative hypotropia and elevation deficits were noted. RESULTS: The mean preoperative dissociated vertical deviation measured 13.4 delta, and the mean total vertical deviation measured 16.2 delta in primary position at 6 meters. The mean dissociated vertical deviation at last follow-up measured 6.7 delta, and the mean total vertical deviation was 7 delta. The dissociated vertical deviation remained controlled based on objective evaluation and subjective patient/relative response in 19 of 22 eyes after a mean follow-up of 2 years (range, 1 to 4.9 years). It recurred in one eye by 6 months postoperatively and in 3 eyes at the last examination. The inferior oblique overaction did not recur to a significant extent in any patient. The best results were achieved in eyes with preoperative dissociated vertical deviations less than 15 delta (0 of 11 failures). When the preoperative dissociated vertical deviation measured > 15 delta, 3 of 11 were failures. Postoperative primary position hypotropia was uncommon (1 of 17 patients), whereas 27% of eyes had mild postoperative elevation deficits in abduction and adduction. CONCLUSION: Anterior transposition of the inferior oblique is an effective treatment for dissociated vertical deviation with inferior oblique overaction but may be less stable in the long term when the preoperative dissociated vertical deviation is in excess of 15 delta.

Adolescent↗
PubMedDate not supplied

Characteristics of peripheral and peritoneal white blood cells in children with chronic renal failure, dialyzed or not.

OBJECTIVE: To explore further the mechanisms leading to immune deficiency in chronic renal failure and the role of dialysis treatment in these mechanisms. DESIGN: Cross-sectional and longitudinal analysis. PATIENTS: We studied 39 children treated with peritoneal dialysis (PD), 23 children treated with hemodialysis (HD), 33 children not yet dialyzed [chronic renal failure (CRF)], and 27 healthy children. Peritoneal cells were also obtained from PD children for analysis. METHODS: White blood cells (WBCs) were isolated from blood and peritoneal dialysis effluent by centrifugation. The number of CD2+, CD4+, and CD8+ T cells, B cells, and natural killer cells were measured by flow cytometry. RESULTS: The total peripheral blood lymphocyte count was lower in PD children (2.6 x 10(9)/L), HD children (2.1 x 10(9)/L), and CRF children (2.0 x 10(9)/L) compared with healthy children (3.1 x 10(9)/L, p < 0.05). The B lymphocyte count was also lower in PD children (0.34 x 10(9)/L), HD children (0.22 x 10(9)/L), and CRF children (0.33 x 10(9)/L) compared with healthy children (0.52 x 10(9)/L, p < 0.01). Numbers of CD4+ T cells were not different, but numbers of CD8+ T cells were lower in PD children (0.56 x 10(9)/L), HD children (0.63 x 10(9)/L), and CRF children (0.53 x 10(9)/L) compared with healthy children (0.77 x 10(9)/L, p < 0.05). The count of natural killer cells was lower in PD children (0.21 x 10(9)/L), HD children (0.17 x 10(9)/L), and CRF children (0.18 x 10(9)/L) compared with healthy children (0.50 x 10(9)/L, p < 0.0001). The CD4/CD8 ratio of lymphocytes in peritoneal effluent was 0.8 versus 1.9 in peripheral blood (p < 0.001). The CD2/CD19 ratio was not different. The cell subsets remained stable during the first year of PD treatment. The CD2/CD19 ratio in peritoneal effluent was higher in children with a peritonitis incidence > or = 1 per year. CONCLUSIONS: The reduced numbers of B lymphocytes, CD8+ T cells, and natural killer cells found in CRF children, dialyzed or not, may favor the frequent occurrence of infections.

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