In multiple linear regression analysis we found signifi-cant correlation between 6MWD and BMI (b = 0.41,p < 0.0001) and arterial hypertension (b = �0.16,p = 0.04). Females had significantly shorter 6MWDthan males (401.1 ± 83.6 m and 451.8 ± 107 m, respec-tively; p = 0.01). Difference was significant after adjust-ment for BMI and age (analysis of covariance) –R = 0.61, R2 = 0.38 (p < 0.0001).Conclusions: BMI, female sex, arterial hypertension andlower: daytime PaO2, FVC, FEV1 were related to short-er 6-min walking distance in OSA patients.

doi:10.1016/j.sleep.2006.07.266

P458 Even non-apneic snoring women from the general

population show symptoms of sleep-disordered breathing

M. Svensson 1,*, C. Janson 2, K. Franklin 4, J.-E.

Broman 3, J. Theorell-Haglow 2, E. Lindberg 2

1 Department of Surgical Sciences, Otolaryngology and

Head- and Neck Surgery2 Department of Medical Sciences, Respiratory Medicine

and Allergology3 Department of Neuroscience, Psychiatry, Uppsala Uni-

versity, Uppsala, Sweden4 Department of Respiratory Medicine, University Hos-

pital, Umea, Sweden

Objectives: Snoring is often regarded as harmless whennot associated with apneas, and not considered to needtreatment. The aim of this study was to investigatesymptoms associated with snoring and compare themto symptoms of OSA in a population-based sample ofwomen.Materials and methods: A population-based sample of400 women aged 20 – 70 years underwent a full-nightpolysomnography and answered questionnaires con-cerning potential symptoms of sleep-disordered breath-ing. Non-snoring subjects with an apnea-hypopneaindex (AHI) < 15 served as controls (n = 183). Group1 comprised subjects with habitual snoring but withoutsleep apnea (AHI < 15, n = 78), group 2 non-snoringsubjects with AHI P 15 (n = 60), and group 3 habitualsnorers with AHI P 15 (n = 74).Results: Compared to controls, all three groups reportedsignificantly higher prevalences of dry mouth on awak-ening (16% in controls, compared to 35, 33 and 50%,respectively). Nocturia was associated with AHI ofP15 (controls = 34%, group 2 = 52% (p = 0.02); group3 = 56% (p = 0.001)) but not to snoring without sleepapnea. Several symptoms were reported more oftenamong snorers regardless of the presence of apneas;waking up unrefreshed in the morning (controls = 20%,group 1 = 41% (p = 0.0006); group 3 = 37%

(p = 0.005)); falling asleep involuntarily during day(controls = 6%; group 1 = 20% (p = 0.001); group3 = 16% (p = 0.009)) morning headaches (con-trols = 27%; group 1 = 40% (p = 0.04); group 3 = 42%(p = 0.02)); and excessive daytime sleepiness (con-trols = 15%; group 1 = 32% (p = 0.002); group3 = 27% (p = 0.04)). For the non-snoring women withsleep apnea the prevalence of these symptoms did notsignificantly differ from controls.Conclusion: In a population-based sample of womensnoring is associated with several symptoms regardlessof concomitant sleep apnea. If the aim of treatment isto reduce symptoms, these data indicate that also habit-ual snorers without sleep apnea should be offeredtreatment.

doi:10.1016/j.sleep.2006.07.267

P459 Profile of elderly persons with sleep disordered

breathing with and without insomnia

Peter Johansson 1,2,*, Urban Alehagen 1,2, Ulf

Dahlstrom 1,2, Eva Svanborg 3,4, Anders Brostrom 1,2,3

1 Department of Cardiology, Linkoping University Hos-

pital, S-58185 Linkoping, Sweden2 Department of Medicine and Care, Faculty of Health

Sciences Linkoping University, Linkoping, Sweden3 Division of Clinical Neurophysiology, Linkoping Uni-

versity Hospital, S-58185 Linkoping, Sweden4 Department of Neuroscience and Locomotion, Faculty

of Health Sciences Linkoping University, Linkoping,

Sweden

Background: Sleep disordered breathing (SDB) andinsomnia are common sleep disturbances, especiallyamong elderly persons. Their co-existence is howevercomplex. In patients with SDB there are often discrep-ancies between objective measures of sleep and self-re-ports of sleep quality.Aim: To investigate if there are any differences in param-eters of SDB, psychiatric disturbances, as well as day-time sleepiness in those having SDB with and withoutinsomnia.Design and methods: A cross sectional cohort design wasused. 346 elderly subjects (47% males), 75–85 years vol-unteered for a one night home sleep respiratory record-ing. The participants also answered to questionnairesregarding sleeping problems (Uppsala Sleep InventoryQuestionnaire), psychiatric disturbances (Hospital Anx-iety Depression Scale) and EDS (Epworth SleepinessScale).Results: SDB (AHI > 5) occurred in 56% (n = 189) ofthe subjects (55% males, p < 0.05). Concerning parame-ters of SDB no significant differences between complain-ers and non-complainers of insomnia were found. But

Abstracts / Sleep Medicine 7 (2006) S1–S127 S115

subjects with non-restorative sleep (NRS) showed atrend to higher oxygen desaturation index (median11.6 vs 10.2, p = 0.06) and those with difficulties initiat-ing sleep (DIS) a trend to lower nadir O2(Q25 78% vsQ25 81%, p = 0.06). Increased depression scores werefound in subjects with difficulties maintaining sleep(p = 0.04), early morning awakenings (p < 0.001) andNRS (p = 0.002) as well as a trend to be higher in thosewith DIS (p = 0.06). Scores of anxiety and EDS wereincreased in the NRS group only (p = 0.006 andp = 0.025). Significantly higher scores of nocturnaldyspnoea, indicating more complaints, were found inall insomnia groups. This was also true concerning noc-turnal arrhythmia for all insomnia groups with theexception of DIS.Conclusion: Complaints of insomnia in patients withSDB are probably more related to the psychological sta-tus, such as depression. Assessing insomnia when treat-ing patients with SDB might be therefore of importance,since depression in patients with different chronic diseas-es has been found to increase the risk for a non-compli-ant behaviour to treatment.

doi:10.1016/j.sleep.2006.07.268

P460 Prevalence of restless legs syndrome at a neurology

clinic in Korea

Ilhee Hong *, Jinkyu Han

Seoul Sleep Center, Korea

Background: Restless legs syndrome (RLS) is a sensory-motor disorder characterized by a distressing urge tomove the legs, onset or exacerbation with rest, relief withmovement, and circadian pattern. Although treatmentof RLS is available, this disorder has been frequentlyunrecognized. This study was performed to evaluatethe prevalence and clinical characteristics of RLS innew patients who visited a neurology clinic.Method: New patients, who visited neurology clinic in auniversity affiliated hospital for various problems forone month period, were asked to complete a question-naire including RLS diagnostic criteria and the Pitts-burgh Sleep Quality Index. The responses ofquestionnaires by the patients were reviewed by a sleepdisorder specialist. Other previous medical history wasrecruited and laboratory study including blood test(Fe, TIBC, Ferritin, Hb), lumbosacral spine X-ray,and electro physiologic study were performed.Results: Of 231 patients (86 men and 145 women) whocompleted the questionnaire, 23 (10%) patients werediagnosed as RLS. The prevalence in women (15.2%)was higher than men (1.2%), and highest at patientsaged 40–49 (13.2%). All RLS patients reported sleep dis-turbance: initiation disturbance (65.2%) and frequent

waking (95.7%). Thirteen patients (56.5%) had lowserum Ferritin (mean 33.1 ng/dl: norm >50 ng/dl). Inlumbar X-ray, 8 patients (34.8%) had intervertebral discspace narrowing. Three patients (13%) had aradiculopathy.Conclusion: The prevalence of RLS is not uncommon inpatients who visited a clinic for other problems thanRLS. The more education about RLS is needed inpublic.

doi:10.1016/j.sleep.2006.07.269

P461 Progression of mild obstructive sleep apnea in long

term follow-up

Seppa Juha *, Tuomilehto Henri, Sahlman Johanna, on

behalf of Kuopio Sleep Apnea Group

Kuopio University Hospital, Department of Otorhinolar-

yngology, Kuopio, Finland

Objectives: To compare the effect of different treatmentmodalities on the degree of polysomnographic findingsin mild obstructive sleep apnea (OSA) in long term fol-low-up.Design: Retrospective case note study with two repeatedambulatory polysomnography and outpatient visits.Methods and measurements: Between 1997–2004 a totalof 52 patients with mild obstructive sleep apnea (ODI45–15) were examined in the Department of Otorhinolar-yngology, Kuopio University Hospital, Kuopio, Fin-land. In addition to ambulatory polysomnographythey underwent clinical examination and selection to dif-ferent treatments of OSAS. The mean age of the patientswas 50.5 years (range 31–66). After a mean interval of4.1 years (range 1.3–9) control polysomnography andclinical investigations were repeated. Also all the treat-ments the patients had received for OSA between thesetwo occasions were recorded.Results: The severity of OSA according to oxygen desat-uration index (ODI4) for the whole group turned frommild to moderate or severe (>15) in 24/52 patients(46%). When reviewing the different treatment modali-ties the patients had received it turned out that fromthe operated patients only 2/11 (18%) had a moderateor severe OSAS, but 7/12 (58%) of the patients whohad CPAP-treatment ODI4-index was >15. From thepatients who only had conservative treatment e.g., die-tary counseling, 15/29 (52%) had moderate or severesyndrome after the follow-up period. The changes inbody mass index (BMI) during two occasions did notcorrelate to the selection of different treatmentmodalities.Conclusions: Mild OSA is a progressive syndrome andthe polysomnographic findings get worse in long termfollow-up. With careful patient selection good results

S116 Abstracts / Sleep Medicine 7 (2006) S1–S127