1. |
- Höglund, Niklas, 1968-
(författare)
-
Atrial fibrillation : treatment, associated conditions and quantification of symptoms
- 2017
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia. There is a need for new pharmacological treatment strategies since the current antiarrhythmic drugs have a modest efficacy and may have severe side effects. Cardioversion (CV) of AF offers an opportunity to study related conditions in sinus rhythm (SR) and during AF. Since catheter ablation of AF is a symptomatic treatment, it is important to have tools for measurement of arrhythmia-related symptoms. Aims: To evaluate the effect of atorvastatin on maintaining SR after CV of persistent AF. To assess if highsensitivity C-reactive protein (hsCRP) predicts the recurrence of AF after CV in a population randomized to treatment with either atorvastatin or placebo. To quantify the symptomatic effect of left atrial catheter ablation of AF. To assess if the restoration of SR by CV, in a population with persistent AF, affects sleep apnea. Methods: Paper I: A total of 234 patients were randomized to treatment with either high dose atorvastatin or placebo prior to CV. Paper II: In a pre-specified substudy which included 128 of the patients in study I, hsCRP was analyzed before and after CV. Paper III: Umea 22 Arrhythmia Questions (U22) is a questionnaire that quantifies paroxysmal tachycardia symptoms. A total of 105 patients underwent first-time pulmonary vein isolation and answered U22 forms at baseline and follow-up 304 (SD 121) days after ablation. Paper IV: Polysomnography was performed before and after CV in 23 patients with persistent AF scheduled for elective CV. Results: Paper I: An intention-to-treat analysis with the available data, by randomization group, showed that 57 (51%) in the atorvastatin group and 47 (42%) in the placebo group were in SR 30 days after CV (OR 1.44, 95%CI 0.85–2.44, P=0.18). Paper II: HsCRP did not significantly predict recurrence of AF at 30 days. However, after adjusting for treatment with atorvastatin, hsCRP predicted the recurrence of AF (OR 1.14, 95% CI 1.01–1.27). Six months after CV, hsCRP at randomization predicted recurrence of AF in both univariate analysis (OR 1.30, 95% CI 1.06–1.60) and in multivariate logistic regression analysis (OR 1.33, 95% CI 1.06– 1.67). Paper III: The U22 scores for well-being, arrhythmia as cause for impaired well-being, derived timeaspect score for arrhythmia, and discomfort during attack detected relevant improvements of symptoms after the ablation. U22 showed larger improvement in patients undergoing only one procedure than in patients who later underwent repeated interventions. Paper IV: Obstructive sleep apnea occurred in 17/23 patients (74%), and central sleep apnea in 6/23 patients (26%). Five patients had both obstructive and central sleep apnea. SR at follow-up was achieved in 16 patients. The obstructive apnea-hypopnea index, central apneahypopnea index, and the number of patients with obstructive or central sleep apnea did not differ before and after restoration of SR. Conclusions: Atorvastatin is not a treatment option with regards to maintaining SR after CV in patients with persistent AF. HsCRP was associated with AF recurrence 1 and 6 months after successful CV of persistent AF. U22 quantifies the symptomatic improvement after AF ablation with adequate internal consistency and construct validity. Both obstructive and central sleep apneas are highly prevalent in patients with persistent AF. Obstructive sleep apneas are unaffected by the CV of AF to SR.
|
|
2. |
- Holmlund, Thorbjörn, 1968-
(författare)
-
Evaluation of surgical methods for sleep apnea and snoring
- 2016
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Snoring and obstructive sleep apnea (OSA) are both common disorders with a number of negative health effects. The safety and efficacy of treating snoring and OSA surgically have been questioned and there has been a lack of studies in the field. Aims: 1) To investigate the frequency of serious complications, including death, after surgery for the treatment of snoring and sleep apnea; 2) to evaluate the effect on daytime sleepiness after radiofrequency surgery of the soft palate in snoring men with mild or no OSA; 3) to evaluate the effect of tonsillectomy on sleep apnea in adults with OSA and tonsillar hypertrophy; 4) to investigate the morphology and cytoarchitecture of muscle fibers in human soft palatal muscles with immunohistochemical and morphological techniques. Methods and results: In paper 1, a retrospective database study. All Swedish adults who were treated surgically because of snoring or OSA from January 1997 to December 2005 were identified in the National Patient Register. None of the surgically treated patients died in the peri- and postoperative period. Severe complications were recorded in 37.1 of 1,000 patients treated with uvulopalatopharyngoplasty (UPPP), in 5.6 of 1,000 patients after uvulopalatoplasty (UPP) and in 8.8 of 1,000 patients after nasal surgery. In paper 2, the study was designed as a randomized, controlled trial. 35 snoring men with mild or no OSA were randomized to either radiofrequency or sham surgery of the soft palate. Radiofrequency surgery was not found to be effective since there was no significant difference between the two groups in relation to the Epworth Sleepiness Scale (ESS) or apnea-hypopnea index (AHI) at follow-up. Paper 3 was a prospective study, including 28 patients with an AHI of >10 and with large tonsils. In these patients, tonsillectomy was an effective treatment for OSA; the mean AHI was reduced from 40 units/h to 7 units/h (p<0.001), and the mean ESS was reduced from 10.1 to 6.0 (p<0.001) at the six-month follow-up after surgery. Minor and moderate swallowing dysfunction was found in seven of eight patients investigated before surgery and the swallowing function improved in 5 of them after surgery, while no one deteriorated. In paper 4, we investigated the morphology and cytoarchitecture in normal soft palate muscles. Human limb muscles were used as reference. The findings showed that the soft palate muscle fibers have a cytoskeletal architecture and cellmembrane complex that differs from that of the limb muscles. Conclusions No case of death related to surgery was found among 4,876 patients treated with UPPP, UPP or nasal surgery for snoring or OSA in Sweden between 1997 and 2005. Radiofrequency surgery of the soft palate has no effect on daytime sleepiness, snoring or apnea frequency in snoring men with mild or no OSA. Tonsillectomy can be an effective treatment for OSA in adults with large tonsils. A subgroup of muscle fibers in the human soft palate appears to have special biomechanical properties and their unique cytoarchitecture must be taken into account while assessing function and pathology in oropharyngeal muscles.
|
|
3. |
- Appelberg, Jonas, 1964-
(författare)
-
Ventilation and Lung Volume During Sleep and in Obstructive Sleep Apnea
- 2003
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Obstructive sleep apnea (OSA) appears to affect up to 5% of the population. The extent to what pulmonary function awake and during sleep relates to obstructive breathing and hypoxemia during sleep in these patients is unclear. The aim of this study was to investigate respiratory function in patients with varying degree of snoring and OSA and to analyse regional lung aeration during sleep.In all, 35 healthy subjects and 90 patients with snoring and OSA were studied. The ventilatory response to CO2 (VRCO2) was measured. Lung function tests were performed. A technique based on computed tomography was developed to study lung aeration during sleep.Patients with OSA displayed a higher VRCO2 in comparison to healthy subjects and snorers (p<0.01). Increased closing volume and reduced expiratory reserve volume (ERV) were found in patients with OSA (p<0.001). In a multiple regression analysis, ERV was an independent predictor of nocturnal apnea (R2=0.13; p=0.001) and desaturation frequency (R2=0.11; p<0.01). In both healthy subjects and OSA patients, lung aeration was reduced during sleep by 0.10 ml gas/g tissue in the dorsal lung region (p<0.05 and p<0.01). OSA patients had a significantly lower gas/tissue ratio in comparison to healthy subjects both awake (-23%; p<0.04) and during sleep (-25%; p<0.04). In a univariate analysis, functional residual capacity (FRC) correlated with the change in lung aeration from wakefulness to sleep (r=-0.78; p<0.001). In patients with OSA, ERV (r=-0.69; p<0.05) and sleep time (r=0.69; p<0.05) correlated with the fall in lung aeration. In conclusion, patients with OSA display an increased ventilatory response to CO2, reduced ERV and increased closing volume. ERV predicts nocturnal apnea and desaturation frequency to a similar extent as obesity. Lung aeration is reduced in the dorsal region during sleep and patients with OSA display a lower amount of gas in comparison to healthy subjects. Decrease in lung volumes, promoting airway closure, and loss of muscle tone contributed to the altered lung function during sleep.
|
|
4. |
- Benedict, Christian, Docent, 1976-, et al.
(författare)
-
Sex-specific association of the lunar cycle with sleep
- 2022
-
Ingår i: Science of the Total Environment. - : Elsevier. - 0048-9697 .- 1879-1026. ; 804
-
Tidskriftsartikel (refereegranskat)abstract
- Using one-night sleep recordings from 852 subjects all living in Uppsala, Sweden, the present study represents one of the largest polysomnography investigations into the association of the 29.53-day long lunar cycle with sleep among men and women and across a wide age range (22–81 years). Following the day after the new moon until the day of the full moon (also named the waxing period), the moon's illumination increases, and the timing of the meridian of the moon is gradually shifted from noontime toward midnight. In contrast, from the day after the full moon until the day of the new moon (also named the waning period), the moon's illumination decreases, and the timing of the meridian of the moon is gradually shifted from early night hours toward noontime. Thus, we focused on the contrast between the waxing and waning periods. Sleep duration was shorter on nights during the waxing period as compared to waning period (P < 0.001). In addition, a significant interaction effect of participants' sex with the lunar period on sleep was noted (P < 0.05). Men, but not women, exhibited lower sleep efficiency (P < 0.001 and P = 0.748, respectively) and were longer awake after sleep onset (P = 0.010 and P = 0.890, respectively) on nights during the waxing period. All associations were robust to adjustment for confounders (including regular sleep disturbances). Our findings suggest that the effects of the lunar cycle on human sleep are more pronounced among men. Based on the cross-sectional design of the study, no firm conclusions can be drawn on the causality of the relations.
|
|
5. |
- Gustafson, Torbjörn, 1953-
(författare)
-
Causes and treatment of chronic respiratory failure : experience of a national register
- 2007
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Long-term oxygen therapy (LTOT) or home mechanical ventilation (HMV) can improve survival time in chronic respiratory failure. A national quality register could be an aid to identifying risk markers and optimizing therapy for respiratory failure. Aims: ▪To identify risk markers for chronic respiratory failure, especially when triggered by chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF). ▪To predict sex-related differences in the future need of LTOT for COPD and to study sex related survival rate in COPD patients starting LTOT. ▪To investigate if HMV is more effective than LTOT alone in treating chronic respiratory failure caused by kyphoscoliosis. ▪To evaluate the use of quality indicators in LTOT. Methods: Swedish national registers for LTOT and HMV were established in 1987 and 1996 respectively. They were reconstructed in 2004 to form the web-based register Swedevox. Indications for LTOT were based on the guidelines from the Swedish Society for Respiratory Medicine. The incidence and prevalence of LTOT for COPD were measured annually from 1987 to 2000, and the future need for LTOT was estimated on the basis of the frequency of ever smoking in Sweden in 2001 in different age groups. A postal questionnaire on occupational exposures was completed by 181 patients with severe pulmonary fibrosis who started LTOT between 1997 and 2000, and by 757 controls. Odds ratios (ORs) were calculated. Time to death was evaluated in kyphoscoliotic patients starting HMV or LTOT alone in 1996-2004. Ten quality indicators were defined and evaluated based on data from patients starting LTOT in 1987-2005. Results: The incidence each year of LTOT in COPD patients increased more rapidly in women than in men (from 2.0 and 2.8/100,000 in 1987 to 7.6 and 7.1/100,000 in 2000 respectively, (p < 0.001)). Women ran a 1.9 times higher risk than men to develop chronic hypoxemia from COPD and had a higher survival rate during LTOT. In men, IPF was associated with exposure to birch dust with an OR 2.7, (95% confidence interval (CI) 1.30–5.65) and with hardwood dust, OR 2.7 (95% CI 1.14–6.52). Patients with kyphoscoliosis showed a better survival rate with HMV than with LTOT alone with a hazard ratio of 0.30 (95%CI 0.18-0.51), adjusted for age, sex, concomitant respiratory diseases, and blood gas levels. There were improvements in the following eight quality indicators for LTOT: access to LTOT, PaO2 ≤ 7.3 kPa without oxygen, no current smoking, low number of thoracic deformity patients without concomitant HMV, LTOT > 16 hours of oxygen/day, mobile oxygen equipment, reassessment of hypoxemia when LTOT was not started in a stable state COPD, and avoidance of continuous oral steroids in COPD. There was a decline in the indicator PaO2 > 8 kPa on oxygen. First-year survival rate in COPD was unchanged. Conclusions: The incidence and prevalence of LTOT increase more rapidly in women than in men. Survival rate during LTOT in COPD is better in women than in men. Exposure to birch and hardwood dust may contribute to the risk of IPF in men. Survival rate in patients with kyphoscoliosis was three times better with HMV than with LTOT alone. The national quality register for LTOT showed improvements in eight out of ten quality indicators. Levels for excellent quality in the indicators are suggested.
|
|
6. |
- Valham, Fredrik, 1972-
(författare)
-
Obstructive sleep apnea : the relationship to cardiovascular disease, diabetes mellitus, motor vehicle driving and ambient temperature
- 2011
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Obstructive sleep apnea is a common disorder, especially in men. Patients with this condition often snore and suffer from excessive daytime sleepiness. It is a treatable condition related to cardiovascular disease, road traffic accidents and obesity. Aims: To study whether snoring and witnessed sleep apnea are related to diabetes mellitus and whether sleepy subjects who snore or report sleep apneas drive more than others. To investigate whether sleep apnea is related to stroke, mortality and myocardial infarction in patients with coronary artery disease. To study the effect of ambient temperature on sleep apnea, morning alertness and sleep quality in patients with obstructive sleep apnea. Methods and results: Questions on snoring, sleep apnea, daytime sleepiness and yearly driving distance were included in the northern Sweden component of the WHO MONICA study. Analyzed were 7905 randomly selected men and women aged 25-79 years. Snoring and witnessed sleep apnea were related to diabetes mellitus in women, (OR 1.58, p = 0.041 and OR 3.29, p = 0.012 respectively), independent of obesity, age and smoking, but not in men. Sleepy snoring men drove a mean of 22566 km per year which was more than others who drove 17751 km per year independent of age, BMI, smoking and physical activity (p = 0.02). Sleepy men reporting sleep apnea also drove more (p = 0.01). 392 men and women with coronary artery disease referred for coronary angiography were examined with overnight sleep apnea recordings and followed for 10 years. Sleep apnea was recorded in 211 (54%) of patients at baseline. Stroke occurred in 47 (12%) patients at follow up. Sleep apnea was associated with an increased risk of stroke (HR 2.89, 95% CI 1.37 - 6.09, p = 0.005) independent of age , BMI, left ventricular function, diabetes mellitus, gender, intervention, hypertension, atrial fibrillation, a previous stroke or TIA and smoking. The risk of stroke increased with the severity of sleep apnea. 40 patients with obstructive sleep apnea were investigated with overnight polysomnography in ambient temperatures of 16°C, 20°C and 24°C in random order. Total sleep time was a mean of 30 minutes longer (p = 0.009), sleep efficiency higher (p = 0.012), patients were more alert in the morning (p = 0.028), but sleep apnea was more severe when sleeping in 16°C (p = 0.001) and 20°C (p = 0.033) vs. 24°C. The AHI was 30 ± 17 in 16ºC room temperature, 28 ± 17 in 20°C and 24 ± 18 in 24°C. Conclusions: Snoring and witnessed sleep apneas are related to diabetes mellitus in women. Sleepy men who snore or report sleep apnea drive more than others. Sleep apnea is independently associated with the risk of stroke among patients with coronary artery disease. Subjects with obstructive sleep apnea sleep longer, are more alert in the morning after a night’s sleep, but sleep apnea is more severe when sleeping in a colder environment.
|
|