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T Gislason

Publications and source records attributed to T Gislason.

At least 37 records · Page 2Linked to original sources
PubMed1997

Users of antiasthma drugs in Iceland: a drug utilization study.

There has been an increasing consensus worldwide on how to treat asthma, and, simultaneously, an increase in the sales of antiasthma drugs. However, little is known about actual drug use, dosage, combinations of drugs, etc., or about the clinical characteristics of patients using these drugs. All individuals with prescriptions for antiasthma drugs, who came to Icelandic pharmacies during March 1994, were invited to participate. By means of questionnaires, the pharmacists recorded the age and gender of the patient, the specialty of the prescribing doctor, as well as the name of the drug, total amount prescribed, and dosage. The patients were asked to answer another questionnaire on their clinical diagnosis, usage of other antiasthma drugs, etc. The pharmacists registered 2,026 individuals, with 2,687 prescriptions: 1,574 for beta2-agonists, 838 for inhaled corticosteroids, 208 for theophylline, 48 for anticholinergic drugs, and 19 for cromoglycates. One thousand, three hundred and fifty one patients answered the questionnaires. The majority (67%) claimed to have asthma, 18% chronic bronchitis, 11% emphysema and 5% other diseases or symptoms. Among those aged > or = 16 yrs with asthma, 93% used beta2-agonists, 62% inhaled corticosteroids, 19% theophylline, and very few used other drugs. The most commonly used combination (57%) was beta2-agonists with inhaled corticosteroids. Thirty one per cent used beta2-agonists as monotherapy, and 5% used only inhaled corticosteroids. Theophylline was used mainly in combination with beta2-agonists and inhaled corticosteroids. In conclusion, our data suggest that two thirds of antiasthma drug users have asthma and that most are treated according to present guidelines. The use of inhaled corticosteroids, however, seems somewhat less than optimal.

Adolescent↗
PubMed1996

Increased prevalence of sleep disturbances and daytime sleepiness in subjects with bronchial asthma: a population study of young adults in three European countries.

The aim of this study was to investigate whether asthma is associated with decreased quality of sleep and increased daytime sleepiness. The study involved a random population of 2,202 subjects supplemented by 459 subjects with suspected asthma, aged 20-45 yrs. The subjects were from Reykjavik (Iceland), Uppsala and Göteborg (Sweden) and Antwerp (Belgium), and participated in the European Community Respiratory Health Survey. The investigation included a structured interview, methacholine challenge, skinprick tests and a questionnaire on sleep disturbances. Participants in Iceland and Sweden also estimated their sleep times and made peak expiratory flow (PEF) recordings during a period of 1 week. Asthma was defined as self-reported physician-diagnosed asthma with current asthma-related symptoms (n = 267). Difficulties inducing sleep (DIS) and early morning awakenings (EMA) were about twice as common, and daytime sleepiness 50% more common, in asthmatics compared with subjects without asthma. After adjusting for possible confounders, a positive association was found between asthma and: DIS (odds ratio (OR) = 1.8); EMA (OR = 2.0); daytime sleepiness (OR = 1.6); snoring (OR = 1.7); and self reported apnoeas (OR = 3.7). Allergic rhinitis, which was reported by 71% of subjects with asthma, was independently related to DIS (OR = 2.0) and daytime sleepiness (OR = 1.3). A significant correlation was found between the number of asthma-related symptoms and sleep disturbances (p < 0.001). Asthma is associated with decreased subjective quality of sleep and increased daytime sleepiness. Concurrent allergic rhinitis may be an important underlying cause of sleep impairment in asthmatic patients.

Adult↗
PubMed1995

Daytime sleepiness, snoring and gastro-oesophageal reflux amongst young adults in three European countries.

OBJECTIVES: To study the geographical variation in daytime sleepiness, snoring and disrupted breathing during sleep and to identify and compare risk factors using the same method in four European cities. DESIGN: A cross-sectional, multicentre epidemiological survey. SETTING: Reykjavik in Iceland, Uppsala and Göteborg in Sweden and Antwerp in Belgium. PARTICIPANTS: A random population sample of 2202 subjects who participated in the European Community Respiratory Health Survey. MAIN OUTCOME MEASURES: Sleep disturbances and daytime symptoms. RESULTS: At all the centres, 5% of the men and 2-3% of the women reported snoring every night. Daytime sleepiness (DS) was more often reported in Uppsala [odds ratio (OR) and 95% confidence interval: 1.6 (1.2-2.1)] than in the other centres, whilst daytime tiredness (DT) was most common in Reykjavik [ OR 1.8 (1.4-2.1)]. Snoring was positively correlated with age, male gender and body-mass index in all areas. Symptoms of gastro-oesophageal reflux were associated with DS: OR 2.6 (1.5 4.4) and DT: OR 4.5 (2.7-7.6) and disrupted breathing: OR 3.8 (1.4-10). DS and DT were reported more often by women than by men. CONCLUSION: The prevalence of snoring was about the same in all four areas, whilst there was a geographical variation in daytime sleepiness and tiredness. As complaints of DS and DT and disrupted breathing were more common in subjects who reported symptoms of gastro-oesophageal reflux, we suggest that polysomnographic studies comparing sleep patterns in adult patients with and without reflux should be conducted.

Adult↗
PubMed1995

Epidemiological aspects of snoring and hypertension.

Previous studies have reported a great difference in snoring prevalence in different populations. In a recent study on men and women 20-45 y old, living in Sweden (Uppsala, Gothenbourg), Iceland (Reykjavík) and Belgium (Antwerp), data concerning snoring, etc., were collected using the same questions and scales in all the countries. In all four areas the prevalence of snoring was the same: 5% of men and 2-3% of women reported snoring every night. In all areas snoring was positively correlated with age, male sex and body mass index. It was therefore assumed that the previous difference in snoring prevalence is probably an artifact of different methodologies. The connection between snoring and systemic hypertension has been much disputed during the last decade. The high prevalence of hypertension in the sleep apnoea syndrome has been explained by obesity/age/male gender/sleep apnoea and/or snoring. In one recent study snoring did not contribute independently to the prediction of hypertension, while other studies indicate that snoring is an independent risk factor for hypertension. After reviewing some of the epidemiological literature it was found that these studies are bound to identify almost entirely different subgroups of the population as snorers since the prevalence of snoring is rated on different types of frequency scales with words like 'never', 'often' or the number of nights per week. The questions used are also different. In general it can be stated that the smaller the proportion of the population identified as snorers the more often there is a statistically significant association with hypertension. The relationship between snoring and hypertension is considered to be unclear due to the different research methods used, and to the uncertain role played by confounding factors such as obesity. There is a need for population-based, prospective, studies with more uniform definitions of the term 'snoring' based on objective measurements of upper airway resistance during sleep, together with haemodynamic studies.

Journal Article↗
PubMed1995

Basic Nordic Sleep Questionnaire (BNSQ): a quantitated measure of subjective sleep complaints.

Sleep-related breathing disturbances, especially obstructive sleep apnoea syndrome (OSAS), are commonly encountered. Epidemiological studies from different countries have shown that poor sleep and complaints about insufficient sleep or poor sleep are often related to poor health. Different studies are, however, difficult to compare with each other. One of the main reasons for this is the frequent methodological differences between questionnaires. There is a need for uniform methods: we need to know the prevalence and incidence of sleep disorders, judged using the same criteria, and also the severity of each problem, i.e. how often a problem or a symptom happens/occurs. In 1988 the Scandinavian Sleep Research Society formed a task group for developing a standardized questionnaire that could be used as a basis for questionnaires used in the Nordic countries. In this article we describe the Basic Nordic Sleep Questionnaire (BNSQ). The main change compared to many previous questionnaires is the five-point scale (scale from 1 to 5) stressing on how many nights/days per week something happens. The basic scale is: 1, 'never or less than once per month'; 2, 'less than once per week'; 3, 'on 1-2 nights per week'; 4, 'on 3-5 nights per week'; and 5, 'every night or almost every night'. For questions about specific rare events the first category may be divided into 'never' and 'less than once per month'. Habitually occurring events such as 'habitual snoring' are defined here as snoring every night or almost every night. The BNSQ has been used widely in a variety of studies performed in Nordic countries during the last years, and it has proven to be a valid tool.

Journal Article↗
PubMed1995

Snoring, apneic episodes, and nocturnal hypoxemia among children 6 months to 6 years old. An epidemiologic study of lower limit of prevalence.

STUDY OBJECTIVE: To identify a lower limit of the prevalence of sleep-related breathing disturbances among preschool children. DESIGN: A cross-sectional epidemiologic study in two stages, first by questionnaires and second by whole-night investigation of children symptomatic of the sleep apnea syndrome. SETTING: Gardabaer, a small town, 10 km south of Reykjavìk, Iceland. PARTICIPANTS: All children in Gardabaer, 6 months to 6 years old (n = 555). MEASUREMENTS: Symptom score estimated by questionnaire and respiratory events based on overnight oximetry, thermistors, and a static charge sensitive bed. RESULTS: The response rate was 81.8%. Snoring was reported as often or very often among 14 (3.2%) and occasionally by 73 (16.7%). Apneic episodes were reported often or very often among seven (1.6%). Altogether 18 children were highly suspected of the sleep apnea syndrome because of habitual snoring or apneic episodes. The girls (n = 9) were older than the boys (mean age: 46 +/- 21 months vs 20 +/- 12 months, p < 0.001). Eventually 11 children came for a whole-night investigation and 8 of them showed more than three respiratory events per hour of sleep, associated with > or = 4% oxygen desaturation. The lower limit of the sleep apnea syndrome prevalence among these children was thus 2.9% (SE, 0.5%). CONCLUSIONS: Among children, symptoms such as snoring and apneic episodes are reported relatively seldom, but a high proportion of the children with these symptoms have hypoxic respiratory events.

Child↗
PubMed1995

Continuous intrathoracic pressure monitoring with a new esophageal microchip catheter in sleep-related upper airway obstructions.

A new small-diameter microchip catheter, especially developed for continuous intrathoracic pressure monitoring to assess the degree of respiratory obstruction and effort in patients with sleep-related upper airway obstructions, was investigated. The technical performance and clinical applicability of the catheter was tested in a simplified screening study comprising 122 sleep recordings in patients with varying complaints of snoring and daytime tiredness. In six obese snorers, sensitivity of the catheter to apneas, hypopneas, and nonapneic snoring was compared to the traditional assessment of respiratory events by conventional polysomnography. The catheter was found to be easy to handle and introduce, with technical qualities meeting the demands for overnight recordings of intrathoracic pressure variations. Patient tolerance was high (93%), and sensitivity to apneas and hypopneas was equivalent to that of traditional polysomnography. Periods with upper airway obstruction and increased respiratory effort on the borderline between asymptomatic obstructions and obstructions resulting in significant blood-gas changes could be detected primarily with intrathoracic pressure monitoring. Monitoring the intrathoracic pressure variations in the esophagus has been shown previously to reflect respiratory effort. Increased respiratory effort might be one of the explanations for the fragmented sleep patterns and sleep related daytime symptoms sometimes seen in patients without a pathologic respiratory index. In addition to being applicable for the detection of apneas and hypopneas, continuous nocturnal monitoring of the intrathoracic pressure variations also detects small increases in respiratory effort and thus may constitute a valuable tool for the understanding and diagnosis of upper airway resistance syndrome and obstructive sleep apnea syndrome.

Adult↗
PubMed1995

Prevalence of sleep disturbances among young adults in three European countries.

The aim of this investigation was to study the geographic variation in sleep complaints and to identify risk factors for sleep disturbances in three European countries: Iceland (Reykjavik), Sweden (Uppsala and Göteborg) and Belgium (Antwerp). The study involved a random population of 2,202 subjects (age 20-45 years) who participated in the European Community Respiratory Health Survey. The subjects answered a questionnaire on sleep disturbances. Participants in Iceland and Sweden also estimated their sleep habits and sleep times during a period of 1 week in a sleep diary. Habitual (> or = 3/week) difficulties inducing sleep (DIS) were reported by 6-9% and early morning awakenings by 5-6% of the subjects. The estimated number of awakenings and the prevalence of nightmares was significantly lower in Reykjavik. Participants in Reykjavik went to bed at night and woke in the morning approximately 1 hour later than participants at the Swedish centers (p < 0.001). Symptoms of gastroesophageal reflux (GER) were associated with DIS (odds ratio [OR] = 2.7), nightmares (OR = 4.4), longer sleep latency and frequent nocturnal awakenings. Smoking correlated positively to DIS (OR = 1.8) and estimated sleep latency. We conclude that the prevalence of DIS was fairly similar at these four European centers but that there was a variation in the prevalence of nightmares and nocturnal awakenings. The significant correlation between reported GER and subjective quality of sleep should be followed up in studies using objective measurements.

Adult↗
PubMed1993

Snoring, hypertension, and the sleep apnea syndrome. An epidemiologic survey of middle-aged women.

The lower limit of the prevalence of sleep apnea syndrome (SAS) was estimated among women 40 to 59 years old by a two-stage procedure. In the first stage 2,016 questionnaires were mailed. The response rate was 75.6 percent. Daytime sleepiness was reported by 8.2 percent, habitual snoring by 11.2 percent, and intermittent snoring by 21.7 percent. There were altogether 128 women described with systemic hypertension and these women were more than twice as often habitual snorers. Logistic multiple regression analyses showed almost a threefold increase in the predicted prevalence of hypertension among intermittent and habitual snorers compared with nonsnorers in the age group 40 to 49 years old and a 60 percent increase in the 50- to 59-year-old age group. In the second stage, a group of 97 women highly suspected of SAS were selected because of their habitual snoring and daytime sleepiness. Eventually, 35 of these came for night studies and 14 were found to have SAS. Among the 35 women, 12 were hypertensive and nine of these had SAS. We estimated the lower limit of the prevalence of SAS to be 2.5 percent for women 40 to 59 years old. It is concluded that SAS is a relatively common occurrence among women, especially postmenopausal ones, and it is strongly related to hypertension.

Adult↗
PubMed1992

Substance P, thyrotropin-releasing hormone, and monoamine metabolites in cerebrospinal fluid in sleep apnea patients.

The cerebrospinal fluid (CSF) concentrations of thyrotropin-releasing hormone (TRH), substance P (SP), 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid (HVA), and 3-methoxy-4-hydroxyphenyl glycol (MHPG) were measured in 15 consecutive patients with the sleep apnea syndrome (SAS) and in healthy control subjects. Second measurements were performed 6 months after surgical treatment in 10 of the patients. The mean (+/- SD) concentration of TRH-like immunoreactive material (TRH-LIM) (pg/ml) did not differ significantly between patients with SAS (8.1 +/- 2.8) and control subjects (7.5 +/- 2.2). However, postoperatively, this concentration was increased in the six clinically cured patients with SAS, from 6.9 +/- 2.7 to 9.4 +/- 1.6 (p less than 0.03). Substance P-like immunoreactive material (SP-LIM) was higher in untreated patients with SAS than in control subjects: 19.2 +/- 6.7 versus 14.4 +/- 4.2 fmol/ml (p less than 0.02), and the level remained high after operation in the group treated surgically. The HVA, 5-HIAA, and MHPG concentrations were similar in patients with SAS and control subjects, and no consistent changes were found postoperatively. The CSF deviations in TRH-LIM and SP-LIM concentrations in the patients may reflect a primary central nervous system defect or they may be secondary to intermittent nocturnal hypoxia, progressive hypercapnia, and/or sleep fragmentation. In this sense, both these systems may be markers of SAS-SP as a "trait" marker and TRH as an indicator of the current state.

Adult↗
PubMed1992

Airway obstruction, obesity and CO2 ventilatory responsiveness in the sleep apnea syndrome.

In 32 patients with sleep apnea syndrome (SAS), pulmonary function, blood gases and the ventilatory response to CO2 (CO2 VR) were studied before and 6 months after uvulopalatopharyngoplasty. Nine of the SAS patients had airway obstruction (AO-SAS), defined as FEV1.0 < or = 72% of the predicted value. They had a significantly higher PaCO2, lower PaO2 and a lower CO2 VR than the remaining SAS patients. Preoperatively 4 SAS patients were hypercapnic (PaCO2 > 5.8 kPa) and compared with the normocapnic ones they were more obese; in 3 of them FEV1.0 was < or = 72%. The hypercapnic SAS patients had a significantly lower CO2 VR. The CO2 VR was significantly correlated to AO and the degree of oxygen desaturation during sleep, but not to the number of episodes of apnea and hypopnea nor their length. The VR to CO2 did not predict the postoperative outcome. Postoperatively 2 hypercapnic obese AO-SAS patients showed a large decrease in episodes of apnea and hypopnea and an increase in CO2 VR, and became normocapnic. Other patients showed no consistent changes in CO2 VR postoperatively.

Adult↗
PubMed1991

Sleep disturbances in asthma: theophylline versus enprofylline.

A double-blind cross-over study was performed on 22 asthmatic patients receiving maintenance treatment with theophylline who, in a previous study, had reported sleep problems. In one of two three-week periods the theophylline medication was replaced by an equipotent dose of slow-release enprofylline. Analysis of sleep questionnaires answered after each treatment period, and sleep diaries filled in throughout the study, showed no significant differences in the quality of sleep between the treatments. Peak expiratory flow (PEF) in the morning did not differ between the treatment periods, but mean PEF in the evening was slightly higher (20 l/min) during theophylline treatment. It was concluded that replacement of theophylline by enprofylline did not improve the quality of sleep subjectively in this group of theophylline treated asthmatics. The results suggest that adenosine receptor antagonism may not be a significant cause of sleep disturbances in asthmatic patients who are receiving theophylline as maintenance treatment.

Adult↗
PubMed1990

Sleep disturbances in patients with asthma.

The prevalence of sleep complaints and sleep disturbances was studied prospectively in 98 consecutive adult asthmatic patients (mean age 45 years, 46% men) attending an out-patient clinic by means of questionnaires and sleep diaries. The results were compared with those from an age- and sex-matched group of 226 healthy individuals. The most common sleep disturbances among the asthmatic patients were early morning awakening (51%), difficulty in maintaining sleep (DMS; 44%) and daytime sleepiness (44%). With decreasing asthma control (i.e. increased number of acute asthmatic attacks) there was an increase of DMS, nocturnal wakefulness, nocturnal breathing problems and bronchodilator inhalations at night. A decrease in estimated sleep time (P less than 0.05) and increase in nocturnal wakefulness (P less than 0.05) was seen with decreasing daytime FEV1--measured as percentage of the predicted value (%FEV1). There was also significant correlation between increasing age and decreasing %FEV1 (P less than 0.01). Among the 26 patients who were only taking one oral bronchodilator, no definite difference regarding sleep quality was found between those treated with theophylline and those taking an oral beta 2-agonist. The prevalence rates of DIS, DMS and daytime sleepiness were about twice as high among the asthmatic patients than in the healthy population. It is concluded that impaired quality of sleep, with disturbed sleep during the night, early morning awakenings and daytime sleepiness, is common among patients with bronchial asthma.

Acute Disease↗
PubMed1989

Theophylline disturbs sleep mainly in caffeine-sensitive persons.

In order to study effects of theophylline on sleep, a randomised double-blind cross-over study with slow release theophylline vs. placebo was performed on 13 healthy male volunteers (mean age 24 years), eight of whom were considered caffeine-sensitive and five caffeine-insensitive. A sleep diary was filled in during the entire period. At the end of each 2 week study period a sleep questionnaire was filled in and a sleep recording was conducted. Seven of the eight caffeine-sensitive persons reported that their sleep was disturbed during the theophylline period, while none of the five caffeine-insensitive experienced any difference between the periods. Analysis of the sleep diaries (mean +/- SD) revealed a significant increase in sleep latency (16 +/- 11 vs 4 +/- 7 min) and decrease in sleep efficiency (95 +/- 3 vs 98 +/- 3%) among the caffeine-sensitive persons during the theophylline period compared with the placebo period, while no such difference was found among the caffeine-insensitive. We conclude that theophylline seems to disturb sleep mainly in caffeine-sensitive persons.

Caffeine↗
PubMed1989

Increased CSF opioid activity in sleep apnea syndrome. Regression after successful treatment.

The etiology of the SAS is unknown. To test whether endogenous opioids could be pathologically active in SAS, markers of opioid systems were measured in the CSF of 15 patients with SAS and in control subjects. Measured by receptor assay, the concentration of so-called fraction 1 opioid was higher in patients with SAS (3.0 +/- 1.5 pmol/ml; mean +/- SD) than in control subjects (1.1 +/- 0.5 pmol/ml) (p less than 0.01), whereas that of fraction 2 opioid was similar in the two groups. Beta-endorphin-like activity, measured by radioimmunoassay, was somewhat lower in patients with SAS (14.0 +/- 2.8 pmol/ml) than in control subjects (21.8 +/- 7.6 pmol/ml) (p less than 0.05). Six months after surgical treatment of the soft palate, new measurements were made in eight patients. Fraction 2 endorphin and beta-endorphin showed no consistent changes. A decrease in the level of fraction 1 from 4.1 +/- 1.5 pmol/ml to 2.3 +/- 1.0 pmol/ml (p less than 0.02) was noted in those six patients showing a successful clinical course. The data support the hypothesis that in SAS the opioid activity is increased.

Adult↗
PubMed1989

Transcutaneous CO2 monitoring in adults with sleep-related breathing disorders.

The accuracy of transcutaneous CO2 monitoring (PtcCO2) was studied in 22 subjects suspected of having sleep-related breathing disorders, by comparison with arterial CO2 measurements (PaCO2). At rest 40 simultaneous sets of PaCO2 and PtcCO2 were obtained. The mean PaCO2 (+/-SD) was 5.3 +/- 0.9 kPa and PtcCO2 was 5.7 +/- 1.0 kPa (r = 0.79). The ventilatory response to CO2 was evaluated by a CO2 rebreathing method, and simultaneous measurements of PaCO2, PtcCO2 and end-tidal PCO2 (PETCO2) were made every min. Both PaCO2 and PETCO2 increased more during the first min of CO2 rebreathing than PtcCO2 (p less than 0.001). Between 1 to 5 min after the start of rebreathing there were no significant differences between the three methods. During sleep there was an increase in PtcCO2 (by 0.1-0.3 kPa) with each apneic event, the magnitude of the increase depending on the length and distribution of these events. With repeated long apneas there was a cumulative increase in PtcCO2, especially during REM sleep. Continuous PtcCO2 monitoring proved useful in monitoring and diagnosing sleep-related breathing disorders.

Adult↗
PubMed1989

High ventilatory response to hypoxia in hypertensive patients with sleep apnea.

The ventilatory response to hypoxia (VRH) in relation to daytime arterial blood pressure was studied in 37 patients with the sleep apnea syndrome (SAS). The patients were divided into hypertensives (n = 16) and normotensives (n = 21). The hypertensive group had a significantly higher VRH (ventilatory increase 1.48 1/min BTPS per percent decrease in arterial oxygen saturation) than the normotensive group (0.69 1/min/%, P less than 0.01). The observed difference raises the question whether a high chemoreceptor sensitivity to hypoxaemia can contribute in causing arterial hypertension among cases with SAS.

Female↗