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Biomedical subjects

L Meyer

Publications and source records attributed to L Meyer.

At least 127 records · Page 7Linked to original sources
PubMed1997

Estimating means and percentages in a complex sampling survey: application to a French national survey on sexual behaviour (ACSF). Analyse des Comportements Sexuels en France.

Two-phase stratification sampling with unequal selection probabilities is a relatively cost-efficient strategy to address problems on a nationwide basis and to perform comparative analyses of specific subgroups. This was the case with the ACSF survey. Specific procedures to estimate the variances of unbiased estimators in complex sampling designs are not included in standard statistical packages and no specialized software is available for two-phase sampling. A detailed synthesis of general basic rules for inference about a target population from a probability sample is first presented. We follow with a standard procedure to estimate means and percentages with their confidence intervals according to the design. Finally, numerical results are discussed.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Spinal cord compression in prostate cancer: treatment outcome and prognostic factors.

BACKGROUND AND PURPOSE: Spinal cord compression (SCC) is an important complication of metastatic prostate cancer. We have analysed patients treated at the Royal Marsden Hospital to assess treatment outcome and prognostic factors in this patients group. MATERIALS AND METHODS: We performed retrospective analysis of 69 patients with spinal cord compression and prostate cancer treated at the Royal Marsden Hospital. RESULTS: At presentation 40 (58%) patients were non-ambulant and 52% were catheterised. Diagnosis was established by myelography in 42% and magnetic resonance imaging (MRI) in 47% of patients. MRI detected significantly more patients with multiple sites of compression (51 versus 7%, P < 0.001). SCC was present at the initial diagnosis of prostatic cancer in 13 patients and 17 patients had received no hormone treatment prior to diagnosis. Following treatment 36 (52%) patients had a functional improvement of motor power with 25/40 (63%) non-ambulant patients becoming ambulant. Seventy-seven percent of patients who had eventual improvement had some improvement in power within 7 days. On multivariate analysis a single level of compression, no previous hormone therapy and a young age (<65 years) predicted for better outcome. When these factors were included an increased radiation dose (>30 Gy) or the addition of surgery did not improve the functional outcome. Following initial recovery; there was a 45% risk of developing a further episode of cord compression at the same or new site by 2 years with a median time to progression of 236 days (range 47-1215 days). The median survival was 115 days (range 5-2016 days) with 25% of patients surviving for 2 years. Patients with no prior hormone therapy had a median survival of 627 days (range 46-1516 days). Other predictors of improved survival on multivariate analysis were a single site of compression and a haemoglobin over 12 g. CONCLUSIONS: Treatment of SCC in prostate cancer results in improved motor function in the majority of patients. Long-term survival is possible, especially in good performance status patients with no prior hormone treatment. Survivors remain at high risk of subsequent neurological relapse. An early improvement in motor power is a strong predictor of subsequent functional improvement. MRI detects additional sites of asymptomatic SCC which makes it the investigation of choice.

Aged↗
PubMed1997

Adjunctive use of monthly physician questionnaires for surveillance of surgical site infections after hospital discharge and in ambulatory surgical patients: report of a seven-year experience.

We report our experience with the use of monthly physician questionnaires, in conjunction with traditional in-house monitoring, for surveillance of surgical site infections (SSIs) in inpatients after hospital discharge and in ambulatory surgical patients (i.e., those not requiring perioperative hospitalization) over a 7-year period (July 1988 to June 1995) involving 156,977 surgical procedures. The mean annual response rate was 73% and did not change significantly from year to year (range, 71% to 75%), but the proportion of surgical procedures covered by returned surveys increased during the study period from 75% to 81% in inpatients and from 78% to 86% in ambulatory surgical patients (p < 0.0001 for both comparisons). Of 1051 SSIs identified, 231 (22%) were identified solely by the survey: 16% of SSIs in inpatients after discharge and 66% of SSIs in ambulatory surgical patients. Of 787 cases meeting the criteria for SSI on the basis of in-house surveillance and listed on returned questionnaires, 366 (47%) were not marked as SSIs by the responding surgeons. We conclude that since its implementation in 1988, monthly physician surveys at our medical center continue to contribute significantly to identification of otherwise undetected SSIs. However, monthly questionnaires should only complement, not replace, traditional in-house surveillance.

Ambulatory Surgical Procedures↗
PubMed1997

Influence of age at infection on human immunodeficiency virus disease progression to different clinical endpoints: the SEROCO cohort (1988-1994). The Seroco Study Group.

METHOD: The influence of age at infection on progression of human immunodeficiency virus (HIV) disease to different clinical endpoints was studied among 393 HIV-seropositive adults selected from the French SEROCO cohort; follow-up lasted from January 1988 to November 1994. Selected patients had a known date of infection and were enrolled shortly after seroconversion. Age-associated risk ratios (RR) were estimated using the Cox model (age fitted as a continuous variable and RR expressed for each 10-year increment after adjustment for symptomatic primary infection and sexual preference). RESULTS: Age had a weak influence on progression from the date of infection to the first category B event (crude RR = 1.15; adjusted RR = 1.09; 95% confidence interval [CI]: 0.89-1.36) but a marked influence on progression from the first category B to the first category C event (crude RR = 1.95; adjusted RR = 1.97; 95% CI: 1.37-2.79). Similar results were obtained after adjustment for the CD4+ cell count at enrollment. A qualitative CD4+ cell defect could explain the influence of age, but this remains to be confirmed. CONCLUSION: Age at infection should be included in the definition of CD4+ cell count thresholds for clinical management and treatment initiation. Risk factors for progression should be assessed according to the different clinical endpoints.

Adolescent↗
PubMed1997

Pregnancy and contraception in a French cohort of HIV-infected women. SEROCO Study Group.

OBJECTIVE: To describe the impact of HIV diagnosis on contraception, incidence of pregnancy and live-births among HIV-infected women in France. DESIGN: Follow-up of women included in a French cohort of HIV-infected adults (SEROCO). METHODS: In 17 hospital-based units and one private practitioners' network in the Paris area and south-east region of France, 412 HIV-infected women (volunteers) were enrolled from 1988 to 1993, shortly after HIV diagnosis (median, 3 months), and followed for a median of 3 years. The main outcome measures were incidence and outcome of pregnancy, proportions of women sexually active and methods of contraception. RESULTS: The incidence of pregnancy decreased significantly from 20.4 per 100 person-years in the year preceding HIV diagnosis to 7.9 per 100 person-years after HIV diagnosis (P < 0.001), whereas the proportion of pregnancies voluntarily interrupted doubled (63 versus 29%). The proportion of women who were sexually inactive increased from 5% before HIV diagnosis to 20% thereafter. During followup, 80% of sexually active women were using contraceptive methods. CONCLUSIONS: The study supports an association between the discovery of HIV infection and a decrease in the proportion of women who are sexually active, a decrease in the incidence of pregnancy in general and live-births in particular, and an increase in the proportion of pregnancies voluntarily interrupted. Nevertheless, 24% of the women became pregnant and around 20% of sexually active women were not using any contraception. The high rate of voluntary abortion may indicate that many of these pregnancies were unplanned and could have been prevented.

Abortion, Induced↗
PubMed1997

Early protective effect of CCR-5 delta 32 heterozygosity on HIV-1 disease progression: relationship with viral load. The SEROCO Study Group.

OBJECTIVE: To determine the influence of heterozygosity for the delta 32 mutant CCR-5 allele on HIV-1 disease progression. DESIGN: HIV-1 disease progression and serum viral load were analysed according to the C-C chemokine receptor (CCR)-5 genotype in 412 Caucasian patients (319 men and 93 women) with a known date of seroconversion, who were enrolled in the SEROCO cohort (median follow-up, 74 months). RESULTS: The frequency of heterozygosity for the mutant allele was 17% and did not differ according to sex or risk factor of HIV infection. Heterozygotes were significantly less likely than patients with two functional alleles to have symptomatic primary infection. Their serum viral load was lower during the 6- to 24-month plateau phase after seroconversion. This difference persisted afterwards, although the rate of decline in CD4+ cells was similar. Kaplan-Meier survival curves showed slower progression to clinical AIDS in heterozygotes during the first 7 years following infection (P < 0.02), the two curves tending to join thereafter (overall log-rank test, P = 0.17). However, the interaction term with time did not reach significance in a Cox model. The overall relative risk of progression was 0.67 (95% confidence interval, 0.38-1.18) and was not influenced by adjustment for age at seroconversion or symptomatic primary infection. After adjustment for early viral load the relative risk was 0.83. Pneumocystis carinii pneumonia and toxoplasmosis were less likely to be the first AIDS-defining illness in heterozygotes than in the other patients (0 versus 24.7% of AIDS cases, P = 0.04), despite similar management. CONCLUSION: Deletion of one CCR-5 gene allele appears to protect against HIV-1 disease progression, mainly during the early years of the infection. Heterozygosity for the deletion leads to persistently lower viral load, and also seems to protect against some opportunistic infections.

AIDS-Related Opportunistic Infections↗
PubMed1997

Has the rate of progression to AIDS changed in recent years?

OBJECTIVES: To investigate whether the rate of progression to AIDS has changed over time by testing an effect of the year of seroconversion on AIDS onset (Centers for Disease Control and Prevention 1987 revised classification), next to an effect of the calendar period of follow-up. DESIGN: French multicentre prospective study of 385 homosexual and heterosexual subjects and 231 subjects from a multicentre study of European injecting drug users (IDU), all with a documented date of HIV-1 seroconversion. METHOD: The effect of the year of seroconversion was compared by the log-rank test. Crude and adjusted relative hazard (ARH) were quantified using the Cox model. Calendar period of follow-up was studied separately for sexual exposure group and IDU and treated as a time-dependent variable in a Cox model. RESULTS: In the 616 study subjects the year of seroconversion was not significantly related to AIDS occurrence (n = 108); the ARH was 0.88 [95% confidence interval (CI), 0.56-1.38] for those who seroconverted in 1988-1989, and 1.17 (95% CI, 0.61-2.25) for those who seroconverted after 1989, compared with those who seroconverted before 1988. In the sexual exposure group, a clear trend towards less rapid progression to AIDS was observed in subjects followed in 1991-1992 (ARH, 0.49; 95% CI, 0.24-0.99) and after 1992 (ARH, 0.54; 95% CI; 0.24-1.21), compared with those followed before 1991. This favorable trend was not observed in IDU despite a significant decrease over time of Pneumocystis carinii pneumonia as AIDS-defining illness. Conversely to sexual exposure groups, the frequency of antiretroviral treatment (mainly zidovudine) prescription was still low during the most recent calendar periods in IDU when the CD4 count threshold of 200 x 10(6)/l was reached. CONCLUSIONS: No evidence was found of a change in the rate of progression to AIDS in subjects who seroconverted in recent years. Furthermore, conversely to sexual exposure groups, the lack of favorable trends in IDU users followed in recent years suggest that health-care systems are not always adapted to their lifestyles.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Sexual factors associated with cytomegalovirus seropositivity in human immunodeficiency virus-infected men. The Seroco Study Group.

BACKGROUND: Many people infected by human immunodeficiency virus (HIV) acquire severe cytomegalovirus (CMV) diseases. Factors associated with CMV seropositivity are poorly documented in sexually active HIV-infected men. GOAL: To study CMV seroprevalence in HIV-infected men according to sexual behavior before the diagnosis of HIV seropositivity. STUDY DESIGN: Cross-sectional study. CMV seroprevalence was studied at enrollment in a prospective cohort of homosexual and heterosexual men infected by HIV through sexual contact. RESULTS: In the study population (n = 723), age, sexual preference, previous lifetime history of sexually transmitted diseases, and multiple sexual partners were independently related to CMV seropositivity. Furthermore, routine condom use during the 6 months before diagnosis of HIV seropositivity was significantly related to CMV seropositivity (adjusted odds ratio [OR]: 0.4, 95% confidence interval [CI]: 0.1-1.0), occasional condom use being of borderline significance [adjusted OR: 0.5, CI: 0.2-1.3]. CONCLUSIONS: This study confirms the importance of sexual factors in the acquisition of CMV infection by HIV-infected men and suggests a protective effect of condom use.

AIDS-Related Opportunistic Infections↗
PubMed1997

High dose methylprednisolone in severe acute transverse myelopathy.

No effective treatment has been shown for patients with acute transverse myelopathy. In an open study five children with severe acute transverse myelopathy were treated with intravenous methylprednisolone and compared with a historical group of 10 patients. The results show that in the methylprednisolone treatment group compared with the historical group of 10 patients: the median time to walk independently was significantly reduced (23 v 97 days); the proportion of patients with a full recovery within 12 months was significantly higher (80 v 10%); all patients had complete motor recovery within one year in contrast with only two of 10 patients in the historical group; and serious adverse effects did not occur. This pilot study suggests that high dose methylprednisolone is effective in the treatment of acute transverse myelopathy.

Acute Disease↗
PubMed1997

Short-term intensive insulin therapy in insulin-requiring diabetes: effectiveness and factors predicting success.

Insulin-requiring diabetes (IRD) is a condition of permanent blood glucose imbalance which occurs despite a regulated diet and treatment with maximum doses of oral anti-diabetic drugs (glibenclamide 15 mg/d + metformin 1,700 mg/d). This report describes the results of a 2-year prospective study in 75 IRD patients treated to eliminate their insulin requirement. All had residual endogenous insulin secretion (REIS) (urinary C peptide > 80 micrograms/24 h and/or basal C peptide > 2.4 ng/ml) and were treated for 10 days by subcutaneous insulin infusion via a portable pump. REIS was measured, and insulin resistance was determined by an insulin tolerance test (ITT) to define their insulin sensitivity index (DG/G) before and after 10-day intensive therapy. The patients were monitored as outpatients, and the attempt at remission was considered to be a failure (F) or a success (S). Thirty of the 75 patients (40%) were in remission at 1 year, and 14/67 (21%) at 2 years. No clinical criterion differentiated successes from failures at 1 year, nor was the initial degree of blood glucose imbalance or the REIS predictive of the metabolic changes that occurred after insulin therapy. However, the drop in the insulin requirement (IR) (-26% for F and -39% for S, p < 0.05) and the increases in the DG/G index (+68 +/- 51% for F and 176 +/- 50% for S, p < 0.01) after insulin therapy were indicative of their condition 1 year later. Receiving operating characteristic curves showed that a 35% decrease in IR and an 80% increase in DG/G were indicative of a successful outcome at 1 year, with a specificity and sensitivity of about 70%. It is concluded that a decrease in daily IR and an increase in the DG/G index during insulin treatment are prognostic indicators of the course of insulin-requiring diabetics after temporary intensive insulin treatment.

Diabetes Mellitus, Type 1↗
PubMed1996

[Induced abortion after the 12th week of pregnancy in the county of Arhus 1993-1994. Psychological consequences].

The records of all women applying for permission to have an abortion performed after the 12th week of pregnancy during a one-year period in the County of Aarhus were continuously reviewed, and the women who had the abortion performed due to psychosocial reasons were interviewed with a questionnaire at the time of the abortion and again four months later. Of the 76 women who applied for permission for a late abortion the following were excluded from the study: 31 who had the abortion because a malformed child was suspected, six women who did not have the abortion although permission had been given, five women who did not receive permission, four who were under 18 years of age, one who had a miscarriage, 10 who were from another country of origin and did not understand Danish and finally four women who were allowed an abortion on a medical indication and who were either in hospital or in jail. Fifteen women were questioned concerning their age, length of pregnancy and psychological and social histories and were asked to fill out a depression scale. The data showed that none of them had planned their pregnancy and they had had no symptoms of pregnancy until the time at which they applied for the abortion. None of them regretted the abortion afterwards; half of the women were under psychological strain at the time of application, and a few of them had even more psychological symptoms four months after the abortion. Although they had many social problems, physical complications and psychological problems only a few of the women had seen a doctor in the four month period between the abortion and the follow-up.

Abortion Applicants↗
PubMed1996

The use of auxiliary events to improve the analysis of survival for HIV-infected patients: application to the French Prospective Multicenter Cohort (SEROCO).

SUMMARY: A multicenter prospective cohort study, including 512 patients for whom date of HIV infection was known, showed that the use of an appropriate auxiliary event can improve the analysis of survival data and lead to an earlier detection of risk factors for HIV patients. Age at seroconversion and primary symptomatic infection were used as risk factors. Two age groups were defined as age at seroconversion >30 years (n = 203) and < or = 30 years (n = 309). Patients with primary symptomatic infection PSI (n = 215) were compared with patients without any clinical manifestation during primary infection (n = 297). Death was considered as the endpoint of primary interest and occurred in 76 patients in the study. Classical non-parametric methods (Kaplan-Meier estimate and long-rank test) and parametric regression model (Weibull model) were used for a standard analysis of survival data. A parametric approach using auxiliary information was used to estimate the survival function and to test the effect of age at seroconversion and PSI. We also applied a recently proposed distribution-free method to produce a non-parametric estimate of the survival function and to test age at seroconversion and PSI with respect to survival estimates. Both methods are compared for two distinct auxiliary events (Karnofsky score below 75 and a first drop of CD4 lymphocyte counts below 200 cells/MM3). The use of CD4 lymphocyte counts below 200 cells/MM3 as an auxiliary event improved the analysis of survival data available in December 1994. For both methods incorporating CD4 counts below 200 cells/mm3 in addition to survival data, the effect of age at seroconversion on survival was significant in April 1992 whereas it was not significant with standard methods. For PSI exposure group, results shown in this work do not indicate any improvement in using auxiliary information. Conditions for using an appropriate auxiliary event as well as advantages and shortcomings of both methods are discussed. Methods used in this work, with appropriate auxiliary information, are promising either through a reduction in the time to follow-up to detect risk factors for cohort studies or the time needed for drug development in clinical trials.

Adult↗
PubMed1996

Structure of the growth hormone-encoding gene and its promoter in mice.

The isolation and nucleotide sequence determination of the 5' flanking region of the mouse growth hormone (mGH)-encoding gene (mGH) is described. The mGH gene consists of five exons and four introns, as is observed in other mammalian species. The second intron in mGH is much smaller than its rat counterpart, thus being similar in size to human, bovine and porcine GH. The transcription start point was determined to be a C residue 62 bp upstream from the start codon, ATG. Analysis of 1767 bp of the 5' flanking region, with respect to putative regulatory elements, revealed a TATA box, two binding sites for growth hormone factor (GHF1), a GC box (SP1), a thyroid-response element (TRE) and a silencer (SiL) sequence motif. As expected, the mGH promoter shows a higher degree of homology with rat, as compared to the other mammalian species like pig, cattle and human, where an overall homology exists only at the proximal promoter region.

Amino Acid Sequence↗
PubMed1996

HEMOCO: a French prospective study of hemophiliacs infected by human immunodeficiency virus type 1 (HIV-1).

HEMOCO is a multicenter prospective cohort set up in 1989 to monitor 407 French hemophiliacs infected by HIV-1 and recruited in 4 hemophilia treatment centers in the Paris region. As of 15 July 1995, 42% of the patients in the cohort had developed stage B HIV disease and 29% stage C disease (AIDS); 23.1% of the patients had died. The cumulative proportion of patients with AIDS was 4.5% at 5 years and 27.4% at 10 years, while the respective mortality rates were 3.8% and 19.5%. In our study, only age was predictive of AIDS, with an estimated relative risk of 1.2 per 10-year age increment; this factor was also predictive of death. After 10 years of follow-up, 6.1% of the study population had no clinical or laboratory signs of immunodepression. The follow-up protocol in the HEMOCO protocol is the same as that in the French SEROCO study, which includes men infected by HIV-1 through sexual contact. This will allow us to compare the progression of HIV infection between these two exposure groups.

Acquired Immunodeficiency Syndrome↗
PubMed1996

Outpatient Hysteroscopy in the Management of Abnormal Vaginal Bleeding

We performed outpatient hysteroscopy with endometrial biopsy in approximately 1000 women under local anesthesia. A definitive management plan was made at the single appointment. The combined results were analyzed by age, symptoms, findings at hysteroscopy, and pathology. Ninety percent of women had abnormal bleeding, 50% of whom had a normal hysteroscopy. Patient acceptability was evaluated by questionnaire. Over 90% of women found the procedure acceptable, with minimal discomfort. The failure rate was approximately 5%. Less than 30% of women required a second surgical procedure. Outpatient hysteroscopy is a safe, effective, and well tolerated alternative to dilatation and curettage under general anesthesia, and has the possibility of a definitive diagnosis and management plan at the patient's first visit. It has clear savings, not only in outpatient and inpatient costs, but also in operating room time.

Journal Article↗