• Correlates of PLMs variability over multiple nights and impact upon RLS diagnosis

      Trotti, Lynn Marie; Bliwise, Donald L; Greer, Sophia A; Sigurdsson, Albert P; Gudmundsdottir, Gudbjorg Birna; Wessel, Thomas; Organisak, Lisa M; Sigthorsson, Thor; Kristjansson, Kristleifur; Sigmundsson, Thordur; et al. (Elsevier Science, 2009-06-01)
      OBJECTIVE: Night-to-night variability of periodic leg movements (PLMs) in restless legs syndrome (RLS) was examined to define the range of intra-subject values, impact upon diagnosing RLS, and clinical correlates. METHODS: Twenty RLS patients were monitored for 10-15 nights using a validated, tri-axial accelerometer worn on the ankle. RESULTS: The mean difference in PLMs index (PLMI) between the lowest and highest night was 25.1/h (range: 3.9-73.8). Inter-subject differences accounted for nearly five times the variance in PLMI relative to between nights within an individual. Based on a single night of recording, PLMI criterion thresholds of 5, 10, and 15/h were exceeded on approximately 70.1%, 51.9% and 34.1% of individual nights among these patients. Based on five randomly sampled nights of recordings, the likelihood that such thresholds were met on at least a single night increased to 91.2%, 80.8% and 62.7%, respectively. Women exhibited greater variability. CONCLUSIONS: Variability in PLMs within RLS subjects was substantial, yet individuals' characteristic PLM level represented a quantitative trait. Variability was unrelated to age or scores on scales of RLS severity, sleepiness, functional status, and mood. A larger number of recording nights increased the likelihood that any criterion was reached.
    • Is snoring during pregnancy a predictor of later life obstructive sleep apnoea? A case-control study.

      Chaggar, Gurpreet; Sutherland, Kate; Han, Fang; Fietze, Ingo; Penzel, Thomas; Benediktsdóttir, Bryndís; Gislason, Thorarinn; Magalang, Ulysses; Pack, Allan I; Singh, Bhajan; et al. (Elsevier, 2020-11-02)
      Background: Obstructive sleep apnoea (OSA) appears common in pregnancy. Complications of pregnancy such as gestational diabetes and hypertension predispose women to cardiometabolic disease in later life. It is unknown if snoring during pregnancy is a risk marker for later-life OSA. Methods: We analysed data from N = 897 women in the Sleep Apnea Global Interdisciplinary Consortium (SAGIC), which recruited patients attending sleep clinics at 11 sites. There were 577 cases with current OSA and 320 controls. Cases were further categorised into mild, moderate, and severe OSA based on apnoea-hypopnoea index. Retrospective self-report of snoring during pregnancy was the exposure of interest and was reported by 2.9% of cases and 3.4% of controls. Results: Multinomial regression demonstrated that snoring during a previous pregnancy was not significantly associated with mild (OR 0.34, 95% CI 0.09-1.25, p = 0.10), moderate (OR 0.69, 95% CI 0.21-2.19, p = 0.52), or severe OSA (OR 1.86, 95% CI 0.77-4.48, p = 0.17) compared to no snoring during pregnancy. Results were unchanged after adjustment for age, body mass index, and ethnicity. 79% of women reported current snoring but all who snored during pregnancy reported current snoring. Conclusions: Women who snore during pregnancy continue snoring in later-life but do not appear more likely to develop OSA. These findings are limited by self-reported data, recall bias, and small numbers of women who reported snoring during pregnancy. A prospective study with objective measurement of sleep and snoring during pregnancy is needed to examine the links between sleep disorders in pregnancy with health in later life. Keywords: Gestation; Risk markers; Sleep disturbance; Sleep-disordered breathing; Snoring; Women.
    • Management of obstructive sleep apnea in Europe.

      Fietze, I; Penzel, T; Alonderis, A; Barbe, F; Bonsignore, M R; Calverly, P; De Backer, W; Diefenbach, K; Donic, V; Eijsvogel, M M; et al. (Elsevier Science, 2011-02)
      OBJECTIVES: In Europe, the services provided for the investigation and management of obstructive sleep apnoea (OSA) varies from country to country. The aim of this questionnaire-based study was to investigate the current status of diagnostic pathways and therapeutic approaches applied in the treatment of OSA in Europe, qualification requirements of physicians involved in diagnosis and treatment of OSA, and reimbursement of these services. METHODS: Two questionnaires were sent to 39 physicians in 22 countries in Europe. In order to standardize the responses, the questionnaire was accompanied by an example. RESULTS: Sleep centers from 21 countries (38 physicians) participated. A broad consistency among countries with respect to the following was found: pathways included referral to sleep physicians/sleep laboratories, necessity for objective diagnosis (primarily by polysomnography), use of polygraphic methods, analysis of polysomnography (PSG), indications for positive airway pressure (PAP) therapy, application of standard continuous PAP (CPAP) therapy (100% with an CPAP/APAP ratio of 2.24:1), and the need (90.5%) and management of follow-up. Differences were apparent in reimbursement of the diagnostic procedures and follow-up, in the procedures for PAP titration from home APAP titration with portable sleep apnea monitoring (38.1%) up to hospital monitoring with PSG and APAP (85.7%), and in the qualification requirements of sleep physicians. CONCLUSIONS: Management of OSA in different European countries is similar except for reimbursement rules, qualification of sleep specialists and procedures for titration of the CPAP treatment. A European network (such as the one accomplished by the European Cooperation in Science and Technology [COST] B26 Action) could be helpful for implementing these findings into health-service research in order to standardize management in a cost effective perspective.
    • Prevalence of restless legs syndrome among adults in Iceland and Sweden: Lung function, comorbidity, ferritin, biomarkers and quality of life

      Benediktsdottir, Bryndis; Janson, Christer; Lindberg, Eva; Arnardóttir, Erna Sif; Olafsson, Isleifur; Cook, Elizabeth; Thorarinsdottir, Elin Helga; Gislason, Thorarinn; Faculty of Medicine, University of Iceland, Iceland. (Elsiver Sciencs, 2010-12)
      OBJECTIVE: This study investigates the prevalence and the association between restless legs syndrome (RLS) and a large variety of health variables in two well-characterized random samples from the general population in Reykjavik, Iceland, and Uppsala, Sweden. METHODS: Using the national registries of inhabitants, a random sample from adults aged 40 and over living in Reykjavík, Iceland (n=939), and Uppsala, Sweden (n=998), were invited to participate in a study on the prevalence of COPD (response rate 81.1% and 62.2%). In addition, the participants were asked to answer the following questionnaires: International RLS Rating Scale, Short Form-12, the Epworth Sleepiness Scale, and questions about sleep, gastroeosophageal reflux, diabetes and hypertension, as well as pharmacological treatment. Interleukin-6 (IL-6), C-reactive protein (CRP) and ferritin were measured in serum. RESULTS: RLS was more commonly reported in Reykjavik (18.3%) than in Uppsala (11.5%). Icelandic women reported RLS almost twice as often as Swedish women (24.4 vs. 13.9% p=0.001), but there was no difference in prevalence of RLS between Icelandic and Swedish men. RLS was strongly associated with sleep disturbances and excessive daytime sleepiness. Subjects with RLS were more likely to be ex- and current smokers than subjects without RLS (p<0.001). Respiratory symptoms and airway obstruction were more prevalent among those reporting RLS and they also estimated their physical quality of life lower than those without RLS (p<0.001). RLS was not associated with symptoms of the metabolic syndrome like hypertension, obesity, markers of systemic inflammation (IL-6 and CRP) or cardiovascular diseases. Ferritin levels were significantly lower in RLS participants (p=0.0002), but not (p=0.07) after adjustment for center, age, sex and smoking history. CONCLUSION: Restless legs syndrome was twice as common among Icelandic women compared to Swedish women. No such difference was seen for men. RLS was strongly associated with smoking and respiratory symptoms, decreased lung function, sleep disturbances, excessive daytime sleepiness, and physical aspects of life quality. RLS was not associated with markers of the metabolic syndrome like hypertension, obesity, cardiovascular diseases or biomarkers of systemic inflammation.
    • Sleep time and sleep-related symptoms across two generations - results of the community-based RHINE and RHINESSA studies.

      Lindberg, Eva; Janson, Christer; Johannessen, Ane; Svanes, Cecilie; Real, Francisco Gomez; Malinovschi, Andrei; Franklin, Karl A; Holm, Mathias; Schlünssen, Vivi; Jogi, Nils Oskar; et al. (Elsevier Science, 2020-01-10)
      Study objectives: To analyze the association between sleep-related symptoms and sleep length in parents and their children in relation to other risk factors in both generations. Method: The participants were parents (n = 5,855, age 54.3 ± 6.5 years, 45.2% men) who participated in the community-based Respiratory Health in Northern Europe (RHINE) study and one random member of their adult offspring (n = 5,855, age 30.2 ± 7.7 years, 41.5% men) who participated in the Respiratory Health in Northern Europe, Spain and Australia (RHINESSA) study. Both generations responded to identical questionnaires on sleep symptoms, including difficulty initiating sleep (DIS), difficulty maintaining sleep (DMS), early morning awakening (EMA), snoring, nocturnal sweating, nocturnal gastroesophageal reflux (nGER), sleep time and excessive daytime sleepiness (EDS). Insomnia was defined as either, or both, DIS and DMS in combination with EDS. Results: All sleep variables except nocturnal sweating were more common in offspring whose parents had reported the same symptom. After adjusting for age, gender, BMI, smoking, physical activity, education, center and parents' total number of children, there were independent associations between sleep symptoms in parents and offspring for DIS (adj. OR, 95% CI: 1.52, 1.20-1.93), DMS (1.34, 1.15-1.56), snoring (1.45, 1.15,1.83), nGER (1.65, 1.15-2.37), insomnia (1.39, 1.13-1.73), short sleep time (<6 h/night) (2.51, 1.72-3.68) and EDS (1.48, 1.26,1.72). There were no independent relationships between symptoms in parents and offspring for EMA, nocturnal sweating or long sleep time (>9 h/night). Conclusion: The familiar aggregation of many sleep disturbances was not explained by investigated lifestyle and environmental factors. This supports a heritable factor in sleep problems.
    • Women with symptoms of sleep-disordered breathing are less likely to be diagnosed and treated for sleep apnea than men.

      Lindberg, Eva; Benediktsdottir, Bryndis; Franklin, Karl A; Holm, Mathias; Johannessen, Ane; Jögi, Rain; Gislason, Thorarinn; Real, Francisco Gomez; Schlünssen, Vivi; Janson, Christer; et al. (Elsevier Science, 2017-07)
      Women are often underrepresented at sleep clinics evaluating sleep-disordered breathing (SDB). The aim of the present study was to analyze gender differences in sleep apnea diagnosis and treatment in men and women with similar symptoms of SDB.