Novel parameters for evaluating severity of sleep disordered breathing and for supporting diagnosis of sleep apnea-hypopnea syndrome.

Sleep apnea-hypopnea syndrome (SAHS) is a complex public health problem causing increased risk of cardiovascular diseases. Traditionally, evaluation of the severity of the disease is based on Apnea-Hypopnea Index (AHI). It is defined as the average number of apnea and hypopnea events per hour during sleep. However, e.g. the total duration and the morphology of the recorded events are not considered when evaluating the severity of the disease. This is surprising, as increasing the length of apnea and hypopnea events will most likely lead to longer and deeper oxygen desaturation events. Obviously, this is physiologically more stressful and may have more severe health consequences than shorter and shallower desaturation events. Paradoxically, the lengthening of apnea and hypopnea events may even lead to a decrease in AHI and oxygen desaturation index (ODI). This raises the question of whether additional information is needed besides AHI and ODI for the evaluation of the severity of SAHS and its potential cardiovascular consequences. In the present paper, several novel parameters are introduced to bring additional information for evaluation of the severity of SAHS. Besides the number of events per hour, that AHI and ODI takes into account, the duration of the breathing cessations and the morphology of the oxygen desaturation events are considered as important factors that may influence the daytime fatigue and also the related cardiovascular problems. In this study diagnostic ambulatory polygraphy recordings of 19 male patients were retrospectively analysed. Importantly, the novel parameters showed significant variation amongst patients with similar AHI. For example, the correlation between AHI and the Obstruction severity-parameter was only moderate (r(2)=0.604, p<0.001). This suggests that patients with similar AHI may exhibit significantly different cardiovascular stress related to the disease. It is suggested that the present novel parameters might provide additional information over the currently used parameters and support the evaluation of the severity of SAHS.

Mortality in middle-aged men with obstructive sleep apnea in Finland.

INTRODUCTION: Obstructive sleep apnea (OSA) has been associated with an elevated rate of cardiovascular mortality. However, this issue has not been investigated in patients with elevated proneness to cardiovascular diseases. Our hypothesis was that OSA would have an especially adverse effect on the risk of cardiovascular mortality in Finnish individuals exhibiting elevated proneness for coronary heart diseases. METHODS: Ambulatory polygraphic recordings from 405 men having suspected OSA were retrospectively analyzed. The patients were categorized regarding sleep disordered breathing into a normal group (apnea hypopnea index (AHI) < 5, n = 104), mild OSA group (5 ≤ AHI < 15, n = 100), and moderate to severe OSA group (AHI ≥ 15, n = 201). In addition, basic anthropometric and health data were collected. In patients who died during the follow-up period (at least 12 years and 10 months), the primary and secondary causes of death were recorded. RESULTS: After adjustment for age, BMI, and smoking, the patients with moderate to severe OSA suffered significantly (p < 0.05) higher mortality (hazard ratio 3.13) than their counterparts with normal recordings. The overall mortality in the moderate to severe OSA group was 26.4 %, while in the normal group it was 9.7 %. Hazard ratio for cardiovascular mortality was 4.04 in the moderate to severe OSA and 1.87 in the mild OSA group. CONCLUSIONS: OSA seems to have an especially adverse effect on the cardiovascular mortality of patients with an elevated genetic susceptibility to coronary heart diseases. When considering that all our patients had possibility of continuous positive airway pressure treatment and our reference group consisted of patients suffering from daytime somnolence, the hazard ratio of 4.04 for cardiovascular mortality in patients with moderate to severe disease is disturbingly high.

Nuclear isomers in superheavy elements as stepping stones towards the island of stability.

A long-standing prediction of nuclear models is the emergence of a region of long-lived, or even stable, superheavy elements beyond the actinides. These nuclei owe their enhanced stability to closed shells in the structure of both protons and neutrons. However, theoretical approaches to date do not yield consistent predictions of the precise limits of the 'island of stability'; experimental studies are therefore crucial. The bulk of experimental effort so far has been focused on the direct creation of superheavy elements in heavy ion fusion reactions, leading to the production of elements up to proton number Z = 118 (refs 4, 5). Recently, it has become possible to make detailed spectroscopic studies of nuclei beyond fermium (Z = 100), with the aim of understanding the underlying single-particle structure of superheavy elements. Here we report such a study of the nobelium isotope 254No, with 102 protons and 152 neutrons--the heaviest nucleus studied in this manner to date. We find three excited structures, two of which are isomeric (metastable). One of these structures is firmly assigned to a two-proton excitation. These states are highly significant as their location is sensitive to single-particle levels above the gap in shell energies predicted at Z = 114, and thus provide a microscopic benchmark for nuclear models of the superheavy elements.

Conversion electron cascades in 254(102)No.

The spectrum of prompt conversion electrons emitted by excited 254No nuclei has been measured, revealing discrete lines arising from transitions within the ground state band. A striking feature is a broad distribution that peaks near 100 keV and comprises high multiplicity electron cascades, probably originating from M1 transitions within rotational bands built on high K states.

Anticoagulant treatment of patients with atrial fibrillation in primary health care.

OBJECTIVE: To determine the prevalence of anticoagulant (AC) treatment of patients with atrial fibrillation in primary health care. To identify complications in the same patients during 1 year. DESIGN: Cross-sectional study and 1-year follow-up. SETTING: Seven health centres with a total population of 164093. SUBJECTS: Five hundred and twenty-two anticoagulated patients with atrial fibrillation. RESULTS: The age-adjusted prevalence of AC treated patients with atrial fibrillation was 0.30%. Of the 522 patients, 240 were men, mean age 69.6 years; and 282 women, mean age 75.1 years. At the beginning of the study 85% and after 1 year 81% of the latest prothrombin time values were within recommended range. After 1 year 414 out of the 522 patients continued AC treatment. During the 1-year follow-up 62 patients had minor or major complications. Eleven patients (2.1%) had to discontinue AC treatment because of complications. Prothrombin tests were mainly taken at 3-4 week intervals. CONCLUSION: High quality AC treatment is possible in the hands of general practitioners.

Anticoagulant treatment in primary health care in Finland.

OBJECTIVE: To establish the prevalence of anticoagulant (AC) treatment, the indications, and the quality of care in primary health care. DESIGN: A cross-sectional study, in which patients on AC treatment were identified from laboratory records. The main and second indications for AC treatment and the last value of the AC-test were taken from medical records. SETTING: Eight Finnish health centres with a total population of 182091 inhabitants. RESULTS: A total of 1255 patients on AC treatment were identified, 48% of them men. The mean age was 68.9 years. The age-adjusted prevalence of AC treatment was 0.65%. The commonest main indication was atrial fibrillation (38%). It was the main or second indication in 591 patients (age-adjusted prevalence 0.30%). The next commonest main indication was deep vein thrombosis (15%), followed by pulmonary embolism (8%). A total of 274 (22%) patients were anticoagulated for cerebral circulatory disturbances. 86% of the latest prothrombin time values fell within recommended ranges. CONCLUSION: The prevalence of AC treatment in Finland seems to be high. The proportion of patients with atrial fibrillation is high, differing from the results in other countries. The monitoring of AC-treatment as the general practitioner's responsibility functions well. The quality of care is good, even in older age groups.

Anticoagulant treatment as a risk factor for primary intracerebral haemorrhage.

Forty one (14.2%) of 288 patients with primary intracerebral haemorrhage occurring between September 1985 and December 1989 in Central Finland were on anticoagulant treatment at the onset of symptoms. In a sample of 29,000 subjects from the same population the prevalence of anticoagulant treatment was 1.6% in those aged 40 years or older. The estimated age adjusted odds ratio of being on anticoagulant treatment at the time of primary intracerebral haemorrhage was 6.7 (95% CI from 4.5 to 9.9). The risk was highest during the first year of anticoagulation. Overtreatment (thrombotest value < 5%) was slightly more common among the patients. The haematoma volumes measured from the CT scans were similar in patients on anticoagulant treatment and those not anticoagulated. The case fatality rate during the first week and the mortality during follow up of 32 months were slightly higher, and the functional outcome slightly worse in the anticoagulated group.