Biomedical subjects

V Backer

Publications and source records attributed to V Backer.

At least 55 records · Page 3Linked to original sources

PubMed1994

An 8-year follow-up study of pulmonary function in patients with rheumatoid arthritis.

To evaluate longitudinal alterations in pulmonary function, 63 patients suffering from rheumatoid arthritis (RA) with previously reported reduced pulmonary diffusing capacity were re-examined in an 8-year follow-up study. Cross-sectional examination revealed normal values for vital capacity (VC), forced expiratory volume in 1 s (FEV1) and diffusing capacity per litre alveolar volume (KCO). Total diffusing capacity (DLCO; P < 0.0001), maximal expiratory flow at 75% of expired VC (MEF75; P < 0.0001) and MEF50 (P < 0.01) were decreased. Longitudinal evaluation revealed unchanged MEF50, MEF75 and FEV1, whereas increases in DLCO (P < 0.0001) and KCO (P < 0.0001) and a decrease in VC (P < 0.05) were found. The longitudinal changes in diffusing capacity were unrelated to patient age, disease duration, disease activity in the study period or pulmonary function at the first examination. Thus, in patients suffering from RA, the most prominent functional pulmonary abnormality, decreased diffusing capacity, appeared to improve in the course of time, despite a slight decrease in VC and continued articular disease activity.

Adult↗

PubMed1994

Serum ferritin in children and adolescents. Results from population surveys in 1979 and 1986 comprising 1312 individuals.

Iron stores were assessed by measurement of serum ferritin in a population survey comprising 436 randomly selected urban Danish schoolchildren (219 boys, 217 girls) 7 to 17 years old. Median ferritin values were similar in boys and girls 7 to 13 years old, while 14- to 17-year-old boys had significantly higher values than girls of similar age (p < 0.0001). Boys had stable median ferritin values from 7 to 15 years of age, after which a significant rise was found from 16 to 17 years of age (p < 0.01). Girls had unchanged median ferritin values from 7 to 11 years of age, after which a significant decrease was found from 12 to 17 years of age (p < 0.01). The frequencies of low ferritin values < 16 micrograms/l (indicating absent iron stores) were: Children 7 to 11 years, 1.0%. Boys 12 to 15 years, 4.5%; 16 to 17 years, 0%. Girls 12 to 15 years, 7.6%; 16 to 17 years, 16.7%. Ferritin levels in the reported 1986 survey were significantly higher than those obtained in a similar survey in the same area in 1979. The results indicate an overall increase in iron stores in Danish schoolchildren and adolescents during 1979-1986, possibly due to an increase in the consumption of meat, and in the use of vitamin-mineral supplements containing iron.

Adolescent↗

PubMed1994

Bronchial responsiveness in children and adolescents: a comparison between previously asthmatic, currently asthmatic, and normal subjects.

The aim of this study was to examine the degree of bronchial responsiveness in previously asthmatic subjects. Of 253 patients, born within 1964-1974, followed in the pediatric department at the University hospital in Copenhagen, 224 subjects (89%) were successfully contacted by telephone; of these 195 complained of persistent asthma and 29 (13%) had had no asthmatic symptoms for at least 2 years. On the basis of the degree of respiratory symptoms, 58 individuals were examined at the outpatient clinic. Of these, (1) 19 were previously asthmatics, (2) 20 had current mild asthma, and (3) 19 had current severe asthma. Furthermore, 19 healthy individuals, age-matched with the preceding asthmatic subjects, were selected as controls. In all subjects, skin prick tests, lung function tests, and bronchial challenge tests with inhaled histamine and bronchodilator were performed. Furthermore, the subjects measured their peak expiratory flow (PEF) twice daily during a period of 4 weeks. Of the 39 current asthmatic subjects, 82% had a PC20 < or = 8 mg/ml, whereas all previously asthmatic subjects and the controls had a PC20 > 8 mg/ml. The degree of bronchial responsiveness as indicated by the dose-response slope (DRS), the percentage change in forced expiratory volume in 1 sec (FEV1) per inhaled mumol of histamine, was found to be significantly higher in previously asthmatic patients (median logDRS 0.1 delta %FEV1/mumol) than in controls (median logDRS-0.4 delta %FEV1/mumol) (p < 0.001). Furthermore previously asthmatic subjects had significantly increased change in FEV1 after inhalation of bronchodilator and peak expiratory flow variability compared to controls. These findings suggest that apparently asymptomatic previously asthmatic subjects have increased airway variability.

Adolescent↗

PubMed1994

Usefulness of repeated measurements of bronchial hyperresponsiveness for the diagnosis of occupational asthma.

To assess the usefulness of repeated measurements of nonspecific bronchial hyperresponsiveness (BHR) in the diagnosis of occupational asthma, we studied 26 consecutive patients referred to the Clinic of Occupational Medicine in Copenhagen because of suspected occupational asthma. The diagnosis of bronchial asthma was confirmed in all patients; however, 4 patients were excluded from the study as they had a baseline PC20 FEV1 histamine > 8 mg/ml. A bronchial challenge test with histamine was performed after nonspecific exposure at the workplace and after a specific bronchoprovocation test in the laboratory; substantial increase in BHR (BHRwork and BHRlab, respectively) was defined as a change in PC20 of at least one doubling concentration. A fall in FEV, of at least 20% from baseline after the specific bronchoprovocation test was defined as a positive response (SBPpos). Six patients had BHRwork and 7 patients had BHRlab; 2 patients had both BHRwork and BHRlab. Five patients had SBPpos, of whom 1 had BHRwork and 1 had BHRlab. None of the patients had three positive tests, i.e., BHRwork, BHRlab, and SBPpos. In 3 patients the specific challenge test caused a pronounced decline of lung function and deterioration in the clinical condition. With the results of the specific challenge test as the gold standard, serial measurement of histamine responsiveness may not appear to be a sensitive diagnostic test for occupational asthma. However, the high number of patients with an increase in BHR after specific and/or nonspecific occupational exposure strongly suggests that changes in bronchial responsiveness may identify patients with respiratory symptoms causally related to occupational exposure.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1994

[Cytomegalovirus infection--a review].

Once considered to be an infrequent cause of human disease, human cytomegalovirus (CMV) is now recognized as being one of the most common congenital infections leading to birth defects, and furthermore, it is a common opportunistic infection associated with serious illness and death in immunocompromised patients. CMV has been assigned to the herpes family of viruses. It is an enveloped DNA virus. About 50-60 percent of Danish blood donors have anti-CMV. This figure is dependent on age, race, socioeconomic status, sexual behaviour and geographical area. Patients exhibiting symptoms and signs of primary or reactivated CMV infection should be further evaluated with appropriate laboratory tests, as treatment of CMV disease with antiviral chemotherapy such as ganciclovir or foscarnet, has proven to be effective.

AIDS-Related Opportunistic Infections↗

PubMed1993

[Allergy and bronchial reactivity in children and adolescents from Copenhagen].

The relationship between bronchial responsiveness and the results of a skin prick test was studied in 527 children and adolescents from Copenhagen. All participants completed a questionnaire concerning birth weight, breastfeeding, month of birth, month of examination, allergic symptoms in themselves or their parents. Furthermore, skin prick test reactivity to nine common aero-allergens, lung function, serum IgE, and bronchial responsiveness to histamine and exercise were measured. A total of 158 (30%) subjects showed signs of allergy (defined as a positive reaction to the skin prick test), of whom 53 (10%) subjects had positive skin reactivity and 105 subjects had moderate skin reactivity; 366 (70%) subjects had no signs of allergic disease as measured by the pride test. The most important marker for the degree of bronchial responsiveness was asthma (p < 0.001), month of examination (p < 0.01) and allergy (skin reactivity to one or more allergens) (p < 0.05). Furthermore, the degree of bronchial responsiveness to inhaled histamine was significantly related to a history of asthma in two first degree relatives (p < 0.01) and the skin reactivity to house-dust mites (p < 0.01), whereas the degree of bronchial responsiveness to exercise was significantly associated with the level of serum IgE (p < 0.05), month of birth (p < 0.001) and birth weight (p < 0.05). In conclusion, allergy is an important risk factor for the presence of increased degree of bronchial responsiveness to inhaled histamine and to exercise.

Adolescent↗

PubMed1993

[Cytomegalovirus infection. A review].

Once considered to be an infrequent cause of human disease, human cytomegalovirus (CMV) is now recognized as being one of the most common congenital infections leading to birth defects, and furthermore, it is a common opportunistic infection associated with serious illness and death in immunocompromised patients. CMV has been assigned to the herpes family of viruses. It is an enveloped DNA virus. About 50%-60% of Danish blood donors have anti-CMV. This figure is dependent on age, race, socioeconomic status, sexual behaviour and geographical area. Patients exhibiting symptoms and signs of primary or reactivated CMV infection should be further evaluated with appropriate laboratory tests, as treatment of CMV disease with antiviral chemotherapy such as ganciclovir or foscarnet, has proven to be effective.

Cytomegalovirus Infections↗

PubMed1993

[Respiratory monitoring during sleep].

A review of respiratory disorders of sleep with the possible related clinical alterations are described. Techniques and methods used in non-invasive respiratory monitoring during sleep are presented. Diagnostic events and therapeutic approaches are discussed related to special patient groups: the obstructive sleep apnoea syndrome, asthma, chronic obstructive pulmonary disease and neuromuscular diseases.

Female↗

PubMed1993

[The course of bronchial asthma in adults. Factors of importance for the annual decline of lung function].

The purpose of this study was to describe the relation of various factors of potential importance to the rate of decline in lung function in adults with intrinsic and extrinsic asthma. Of 180 asthmatic patients, 143 (79%) participated in a 10 year follow up examination; 94 patients had intrinsic asthma and 49 extrinsic asthma. Patients with intrinsic asthma had an annual decline in FEV1 of 50 ml, whereas those with extrinsic asthma had a decline of 23 ml; the rate of decline of lung function increased with increasing age in both groups. There was no relation between rate of decline in lung function and number of cigarettes smoked. An inverse relation between initial FEV1 and decline in FEV1 was found for the patients with extrinsic asthma but not for the patients with intrinsic asthma. A high degree of airway variability--that is, reversibility in FEV1--at the time of enrollment was found to be associated with a steeper decline in lung function in patients with intrinsic asthma, whereas increasing degrees of obstruction (decreasing FEV1/VC ratio at enrollment) and need for treatment with corticosteroids were associated with a more pronounced decline in FEV1 in patients with extrinsic asthma. The rate of decline in lung function is greater in patients with intrinsic asthma than in patients with extrinsic asthma; the prognosis for intrinsic and extrinsic asthma is to some extent influenced by different factors, which suggests that the pathogenetic mechanisms underlying intrinsic and extrinsic asthma may differ.

Adult↗

PubMed1993

Relationship between viral antibodies and bronchial hyperresponsiveness in 495 unselected children and adolescents.

The purpose of this study was to investigate whether recent and previous subclinical viral respiratory infection can explain the presence of increased bronchial responsiveness to histamine. We studied a randomly selected population of 495 children and adolescents, aged 7-16 years, from Copenhagen. If the subjects had had symptoms of respiratory infection recently, the examination was postponed for at least 6 weeks. Bronchial hyperresponsiveness (BHR) to inhaled histamine was found in 79 (16%) of the subjects, of whom 28 had asthma. Forty-eight subjects (10%) had increased levels of serum IgM antibodies against either parainfluenza, influenza, adenovirus, or respiratory syncytial virus (RSV), reflecting a recently acquired infection. No association between BHR and antibodies against respiratory viruses was found, as 7 (8.9%) of the 79 subjects with BHR and 41 (9.9%) of the 416 subjects without BHR had viral antibodies. Furthermore, no association between degree of bronchial responsiveness and viral antibodies was found. Moreover, 251 individuals (51%) had signs of earlier RSV infection, i.e. IgG antibodies against RSV. No relationship was found between age of the subjects and the presence of antibodies against either respiratory viruses in general or IgG-RSV. No relationship was found between the presence of antibodies against RSV and BHR; furthermore, evidence of earlier RSV infection was unrelated to the level of lung function and degree of bronchial responsiveness. We conclude that increased bronchial responsiveness in asymptomatic, unselected schoolchildren and adolescents is not likely to be caused by recent or previous viral respiratory infections.

Acute Disease↗

PubMed1993

Pulmonary function in adolescents with childhood asthma.

The aim of this study was to determine the pulmonary function in former and present asthmatics. We examined 77 persons aged 12-24 years, classified into four groups: 1) healthy subjects (controls) (n = 19), 2) former asthmatics (n = 19), 3) present mild asthmatics (n = 20), and 4) present severe asthmatics (n = 19). Although exhibiting no respiratory symptoms, former asthmatics had reduced airflow values measured by FEV1 (median (range) 89.7 (83-99) vs 101.4 (91-110)) and MEF25 (76.5 (68-94) vs 103.0 (97-124)), as compared with controls. Furthermore, former asthmatics had significantly increased PEF variability, as compared with controls, whereas no significant differences were found in static lung parameters, i.e. total lung capacity and residual volume, as compared with controls. In conclusion, former asthmatics, although now exhibiting no respiratory symptoms, were found to have obstructive airflow limitation, increased bronchial responsiveness, and normal lung volumes.

Adolescent↗

PubMed1993

Aerosolized pentamidine for primary prophylaxis of Pneumocystis carinii pneumonia: a controlled, randomized trial.

The objective was to assess the efficacy of a biweekly dose of 60 mg aerosolized pentamidine (AP) for primary prophylaxis (PP) of Pneumocystis carinii pneumonia (PCP) and the impact of prophylaxis on survival in HIV-infected patients. Participants were AIDS patients with no history of PCP, patients with a CD4 count < or = 0.200 x 10(9)/L, or patients belonging to the CDC group IVC2, irrespective of CD4 count. It was an open, randomized, controlled trial. Patients were assigned to receive AP, 60 mg biweekly via a System 22 nebulizer, or to a control group not receiving any prophylaxis. Incidence curves for PCP and survival were generated using the Kaplan-Meier method, stratified by treatment group, and compared using the log-rank test. Data were analyzed according to intention to treat. There were 15 cases of PCP among 105 patients in the AP group and 32 cases among 104 patients in the control group. The cumulative incidence of PCP by 18 months was 13% (95% CI 5-21%) in the AP group and 30% (95% CI 18-41%) in the control group, (p = 0.002). During the study period 19 patients (18%) in the AP group died and 24 patients (23%) in the control group (NS; p = 0.28). We conclude that a biweekly dose of 60 mg AP is efficient as primary PCP prophylaxis when a System 22 nebulizer is used. There was, however, no difference in survival between the groups, suggesting that AP has an impact on morbidity only.

AIDS-Related Opportunistic Infections↗

PubMed1992

Serial pulmonary function tests in patients treated with low-dose amiodarone.

Problems with pulmonary toxicity have emerged as a potentially limiting factor for amiodarone use. We studied 24 consecutive patients receiving low-dose (i.e., less than or equal to 400 mg/day) amiodarone for refractory tachyarrhythmias. Serial pulmonary function test results were correlated with daily dose, serum concentration, cumulated dose, and duration of amiodarone treatment to determine the effect of the drug on pulmonary function. The mean follow-up period for the 24 patients, who completed baseline and follow-up evaluations, was 47 months (range 31 to 75 months). In 22 of the 24 patients a reduction in total diffusion capacity (TLCO) was noted after treatment; for all 24 patients the mean reduction in TLCO was 12.9% of the predicted value (SD 9.6% predicted) (p less than 0.02). The decrease in TLCO was found to be significantly related to an increasing cumulated dose of amiodarone (p = 0.007), whereas the reduction in TLCO was found to be unrelated to sex, age, underlying heart disease, arrhythmia, daily dose of amiodarone, duration of treatment, plasma concentration of amiodarone and desethylamiodarone, and pretreatment pulmonary function abnormalities. Seven (29%) of the patients had asymptomatic pulmonary toxicity with a decrease in TLCO greater than or equal to 20% of the predicted value. In conclusion, long-term treatment with low-dose amiodarone was associated with a substantial decrease in TLCO, a higher cumulative dose of the drug was related to an increasing reduction in TLCO, and pretreatment pulmonary function abnormalities were not predictive for development of subclinical pulmonary toxicity.

Adult↗

PubMed1992

Bronchial responsiveness to exercise in a random sample of 494 children and adolescents from Copenhagen.

To investigate the bronchial response to exercise, we studied a random sample of 494 children and adolescents, aged 7-16 years, from Copenhagen. Exercise challenge consisted of steady running on a 10% sloping treadmill for 6 min in a climate chamber. Furthermore, in 464 subjects a histamine challenge test was also performed. Of the 494 subjects studied, 81 (16%) had at least 10% and 30 (6%) at least 15% reduction in FEV1 within 15 min after exercise. Twenty-nine (6%) subjects had bronchial hyperresponsiveness to both histamine and exercise, 48 (10%) subjects had bronchial hyperresponsiveness to exercise, but histamine responsiveness within the normal range, whereas 340 (73%) subjects had neither bronchial hyperresponsiveness to exercise nor inhaled histamine. With regard to the presence of asthma defined as substantial exercise induced bronchoconstriction (delta-FEV1 greater than or equal to 10%), exercise testing may not be appropriate for identifying clinical asthma in a random sample, because the highest predictive value of a positive test was 25%. On the other hand, a history of clinical asthma was frequently associated with increased bronchial responsiveness to exercise (77%). In conclusion, 16% of a random sample of children and adolescents had abnormal bronchial responsiveness to exercise (delta FEV1 greater than or equal to 10%), 6% of the subjects had a delta FEV1 greater than or equal to 15%. Furthermore, because of a low predictive value of a positive test, the exercise challenge test has only a supplementary role in the detection of clinical asthma in population samples.

Adolescent↗

PubMed1992

Distribution of serum IgE in children and adolescents aged 7 to 16 years in Copenhagen, in relation to factors of importance.

The distribution of total serum-IgE and factors of importance for the level of IgE was studied in a random sample of 508 children and adolescents, aged 7-16 years, from Copenhagen. A detailed history about asthma, rhinitis, dermatitis and urticaria was obtained, and a physical examination, skin prick test with 9 common allergens, lung function test, bronchial challenge with inhaled histamine and exercise, and measurement of IgE (kU/l) were performed. The distribution of IgE among children and adolescents was found to exhibit a log normal distribution and a positive skin prick test, allergic symptoms, a family history of allergic diseases, age and smoking were found to be significantly related to an increased level of IgE. No relationship was found between increased bronchial responsiveness and IgE. The geometric mean of "normal" values of IgE (*1 SD and *2 SD) of the Danish children and adolescents was 18 kU/l (*4.7, *18.2), suggesting that normal IgE values were within 330 kU/l. Measurement of IgE as the only screening for allergic disease is unreliable, as the predictive value of an elevated IgE in population samples was found to be 50%, whereas misclassification (1-specificity) of asymptomatic subjects as allergic because of an increased IgE was low (4%). In conclusion, total IgE is highly influenced by allergen skin reactivity. Further, this study suggests that normal IgE values were within 330 kU/l, although the range was wide.

Adolescent↗

PubMed1992

Bronchodilating effect of ipratropium bromide inhalation powder and aerosol in children and adolescents with stable bronchial asthma.

The purpose of this study was to compare the bronchodilating effect of ipratropium bromide (IB) administered by a conventional Ingelheim powder device system (IPI) and by a metered dose inhaler (MDI) in children and adolescents with stable bronchial asthma. Seventy patients, aged 7 to 16 years, with stable bronchial asthma from our outpatient clinic were tested for bronchial responsiveness to inhaled IB. Fifteen (21%) of the 70 subjects were found to have a substantial bronchial response to inhalation of 40 micrograms IB, i.e. at least 15% increase in FEV1 30 min after inhalation; the remaining 55 subjects had less than 15% increase in FEV1. No relationship between severity of asthma, age or sex and bronchial responsiveness to inhaled IB was found. Among the 15 subjects who had substantial bronchial response to IB, the increase in FEV1 after inhalation of fenoterol tended to be greater than the response to inhaled IB, although this did not reach statistical significance. Responders, i.e. subjects who had at least 15% increase in FEV1 after inhalation of IB, took part in a double-blind, cross-over study of the bronchodilating effect of 40 micrograms IB delivered by IPI and MDI. We found no significant differences in the bronchodilating effect during a 6-h follow-up. Maximum bronchodilating effect of IB was reached after 30 min and the maximum response lasted for 90 min. No side or adverse effects were observed following inhalation of IB.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1992

Distribution of radioactive aerosol in the airways of children and adolescents with bronchial hyper-responsiveness.

The purpose of this study was to examine the relationship between the pulmonary distribution of inhaled radioaerosol, bronchial responsiveness, and lung function in children and adolescents. The participating subjects (n = 39) were divided into three groups: (1) 14 asthmatics with bronchial hyper-responsiveness (BHR), (2) five non-asthmatic subjects with BHR, and (3) 20 controls without BHR. Pulmonary distribution of [99Tcm) albumin radioaerosol, maximal expiratory flow when 25% of forced vital capacity remain to be exhaled (MEF25), and bronchial responsiveness to inhaled histamine were measured. Twenty subjects (52%) had irregular central distribution and 19 subjects (48%) had regular distribution of radioaerosol in their lungs. No difference in distribution of radioaerosol was found between the three groups of children. The median MEF25 among non-asthmatic subjects (80% predicted) was lower than that found in controls (92% predicted) but higher than that found in asthmatic subjects (55% predicted). A relationship was found between reduced flow at the peripheral airways, as indicated by MEF25 and the degree of central distribution of radioaerosol. Furthermore, subjects with irregular central distribution of radioaerosol had an increased degree of bronchial responsiveness. In conclusion, children and adolescents who have flow rates in the peripheral airways or increased degree of bronchial responsiveness tend to have abnormal distribution of radioaerosols.

Adolescent↗

PubMed1992

A 10 year follow up of 180 adults with bronchial asthma: factors important for the decline in lung function.

BACKGROUND: Little is known about the factors that determine outcome in asthma. The purpose of this study was to describe the relation of various factors of potential importance to the rate of decline in lung function in adults with intrinsic and extrinsic asthma. METHODS: Of 180 asthmatic patients, 143 (79%) participated in a 10 year follow up examination. At the time of enrollment all patients underwent certain tests for asthma (case history, total IgE, skinprick tests, the radioallergosorbent test (RAST), histamine release from basophil leucocytes, and specific bronchial provocations). On the basis of these tests 94 patients had intrinsic asthma and 49 extrinsic asthma. RESULTS: Patients with intrinsic asthma had an annual decline in FEV1 of 50 ml, whereas those with extrinsic asthma had a decline of 22.5 ml; the rate of decline of lung function increased with increasing age in both groups. An inverse relation between initial FEV1 and decline in FEV1 (the "horse racing effect") was found for the patients with extrinsic asthma but not for the patients with intrinsic asthma. There was no relation between rate of decline in lung function and number of cigarettes smoked. A high degree of airway variability--that is, reversibility in FEV1--at the time of enrollment was found to be associated with a steeper decline in lung function in patients with intrinsic asthma, whereas increasing degrees of obstruction (decreasing FEV1/VC ratio at enrollment) and need for treatment with corticosteroids were associated with a more pronounced decline in FEV1 in patients with extrinsic asthma. CONCLUSIONS: The rate of decline in lung function is greater in patients with intrinsic asthma than in patients with extrinsic asthma; the prognosis for intrinsic and extrinsic asthma is to some extent influenced by different factors, which suggests that the pathogenetic mechanisms underlying intrinsic and extrinsic asthma may differ.

Adult↗