Characteristics of generalised epileptiform activity.

OBJECTIVE: To study the age-related occurrence of specific features of generalised epileptiform activity (GEA), their correlation with EEG background activity (BA), and their internal correlation. METHODS: 17,723 consecutive routine EEGs from 12,511 patients were annotated and categorised into a database. The first EEG containing GEA from all 325 patients with such activity were selected and categorised for GEA features. The BA was studied in multivariable fractional polynomial regression models including intervening variables. The GEA features were studied in similar models for age-dependency and internal correlation. RESULTS: High GEA-amplitude and low GEA-frequency correlated with BA slowing. The occurrence of 'irregular spike/sharp slow wave' pattern increased with age (p=0.003). Hyperventilation sensitivity was not age-related. There was no correlation between hyperventilation sensitivity and photoparoxysmal response. The age-related probability for specific GEA-types was established. CONCLUSIONS: High GEA-amplitude and low GEA-frequency correlate with BA slowing, indicating cerebral cortical dysfunction. Hyperventilation sensitivity and photoparoxysmal response independently increase the yield of EEG. There is no age-dependency for hyperventilation sensitivity showing that an upper age threshold for hyperventilation provocation is inappropriate. SIGNIFICANCE: The results extend our understanding of GEA and help the electroencephalographer in weighing the various GEA components.

The incidence of adult asthma: a review.

In recent years, several new studies have estimated the incidence of adult asthma. These studies vary in design and quality. The current paper summarises the findings of major population studies in the adult incidence of asthma. The pooled estimate of the adult incidence of asthma was 4.6 per 1000 person-years in women and 3.6 per 1000 person-years in men. The estimate among only general population cohort studies was higher, respectively 5.9 and 4.4 per 1000 person-years in women and men. The adult incidence of asthma was slightly higher in women than men. In the few studies that allowed the incidence of asthma to be estimated among those aged >50 years, there was a trend towards a higher incidence with age. It is thought likely that this is at least partly explained by misclassification with COPD. However, the current findings from these studies may imply that the incidence of asthma in the elderly has previously been under-estimated. Finally, the review shows that estimates of adult asthma incidence have tended to be higher in later studies, implying a rise in asthma incidence in adults within the timeframe of observation.

[Smoking cessation practice among Norwegian hospital physicians]. / Norske sykehuslegers praksis ved røykeavvenning.

BACKGROUND: Limited data is available as to what extent Norwegian hospital doctors ask their patients about their smoking habits, and to what extent doctors offer their patients help in smoking cessation. MATERIAL AND METHODS: A random sample of 1,025 hospital doctors was mailed a questionnaire. After 14 days a reminder letter was sent to non-responders; 76% of the doctors responded. RESULTS: Altogether 98% of the doctors stated that they asked their patients with smoking-related disease about their smoking habits. In cases of non-smoking related disease, 73% of the doctors stated that they asked about the smoking habits of their patients (83% of female and 69% of male doctors). If doctors knew that a patient wanted to quit smoking, 25% of them stated that they often recommended nicotine replacement therapy. Less than 7% of the doctors regularly offered smoking cessation courses, handed out self-assistant material, or gave the patients other smoking cessation advice. INTERPRETATION: The study indicates that doctors often ask their patients about their smoking habits, but there is clear potential for improvement as to the smoking cessation advice.

Comparison of respiratory symptoms questionnaires.

SETTING: Comparisons in performance of questionnaires are of interest in international comparisons of prevalences and risk factors, after translation and development of new questionnaires. Factors such as sex, age, educational level and smoking habits may influence the performance of questionnaires. OBJECTIVE: 1) To discuss questionnaire comparisons in general, using as an example a Norwegian respiratory symptoms questionnaire compared with a translation of the British Medical Research Council questionnaire on chronic bronchitis; and 2) to examine whether reliability differs in subgroups. DESIGN: A population sample of 935 residents of Hordaland County, Norway, completed two questionnaires in a short interval of time. Agreement and Cohen's kappa were calculated. RESULTS: Prevalences were significantly different between the two questionnaires for most symptoms. Agreement decreased from non-smokers through ex-smokers to smokers, whereas the kappa statistic increased. Agreement increased as the educational level increased, whereas the kappa statistic declined. No significant age and sex effects on agreement and kappa were observed. CONCLUSION: Small changes in the phrasing of a question can have considerable effect on prevalence estimates. Reliability statistics are prevalence dependent. Reliability may differ according to smoking habit and educational level. Questionnaires should be tested in the population that they are to be used in.