Effects of long working hours and the night shift on severe sleepiness among workers with 12‐hour shift systems for 5 to 7 consecutive days in the automobile factories of Korea

We investigated the effects of 12‐hour shift work for five to seven consecutive days and overtime on the prevalence of severe sleepiness in the automobile industry in Korea. [Correction added after online publication 28 Nov: Opening sentence of the summary has been rephrased for better clarity.] A total of 288 randomly selected male workers from two automobile factories were selected and investigated using questionnaires and sleep‐wake diaries in South Korea. The prevalence of severe sleepiness at work [i.e. Karolinska Sleepiness Scale (KSS) score of 7 or higher] was modeled using marginal logistic regression and included theoretical risk factors related to working hours and potential confounding factors related to socio‐economic status, work demands, and health behaviors. Factors related to working hours increased the risk for severe sleepiness at the end of the shift in the following order: the night shift [odds ratio (OR): 4.7; 95% confidence interval (CI): 3.6–6.0)], daily overtime (OR: 2.2; 95% CI: 1.7–2.9), weekly overtime (OR: 1.6; 95% CI: 1.0–2.6), and night overtime (OR: 1.6; 95% CI: 0.8–3.0). Long working hours and shift work had a significant interactive effect for severe sleepiness at work. Night shift workers who worked for 12 h or more a day were exposed to a risk of severe sleepiness that was 7.5 times greater than day shift workers who worked less than 11 h. Night shifts and long working hours were the main risk factors for severe sleepiness among automobile factory workers in Korea. Night shifts and long working hours have a high degree of interactive effects resulting in severe sleepiness at work, which highlight the need for immediate measures to address these characteristics among South Korean labor force patterns.     

Enhanced Predictive Power of Quantitative TWA during Routine Exercise Testing in the Finnish Cardiovascular Study

Introduction: We examined whether quantification of T-wave alternans (TWA) enhances this parameter's capacity to evaluate the risk for total and cardiovascular mortality and sudden cardiac death (SCD).
Methods and Results: The Finnish Cardiovascular Study (FINCAVAS) enrolled consecutive patients (n = 2,119; 1,342 men and 777 women) with a clinically indicated exercise test with bicycle ergometer. TWA (time domain-modified moving average method) was analyzed from precordial leads, and the results were grouped in increments of 10 μV. Hazard ratios (HR) for total and cardiovascular mortality and SCD were estimated for preexercise, routine exercise, and postexercise stages. Cox regression analysis was performed. During follow-up of 47.1 ± 12.9 months (mean ± standard deviation [SD]), 126 patients died: 62 were cardiovascular deaths, and 33 of these deaths were sudden. During preexercise, TWA ≥ 20 μV predicted the risk for total and cardiovascular mortality (maximum HR >4.4 at 60 μV, P < 0.02 for both). During exercise, HRs of total and cardiovascular mortality were significant when TWA measured ≥50 μV, with 90 μV TWA yielding maximum HRs for total and cardiovascular death of 3.1 (P = 0.03) and 6.4 (P = 0.002), respectively. During postexercise, TWA ≥60 μV indicated risk for total and cardiovascular mortality, with maximum HR of 3.4 at 70 μV (P = 0.01) for cardiovascular mortality. SCD was strongly predicted by TWA levels ≥60 μV during exercise, with maximum HR of 4.6 at 60 μV (P = 0.002), but was not predicted during pre- or postexercise.
Conclusion: Quantification of TWA enhances its capacity for determination of the risk for total and cardiovascular mortality and SCD in low-risk populations. Its prognostic power is superior during exercise compared to preexercise or postexercise.     

Smoking and unhealthy food habits: How stable is the association?

The aim of this study was to compare the food habits of maleand female current smokers, ex-smokers and never-smokers in1980–1995. Do differences between smoking categories varyby study period or sociodemographic factors? The data were collectedby mailed questionnaires in connection with a nationwide programme,‘Monitoring Health Behaviour among the Finnish Adult Population’.In this study, data from the years 1980–1981, 1987–1988and 1994–1995 were used (n= 5, 773–7, 249, responserate 72–80%). Two examples of healthy food choices wereincluded: avoidance of milk fat and daily use of vegetables.Cross-tabulation and logistic regression analysis were usedto examine the effects of smoking, the time period and sociodemographicfactors on food habits. Male and female smokers used vegetablesand low-fat milk least often. Ex-smokers alone or together withnever-smokers most often avoided milk fat and used vegetables.Among men the differences between ex-smokers and current smokersincreased. Among women the differences in the use of low-fatmilk remained stable; in the use of vegetables, they first increased,then decreased. The differences in food habits between the smokingcategories diminished when educational level was taken intoaccount. After adjusting for place of residence and maritalstatus, the association between smoking and diet persisted.Smokers tended to make unhealthy food choices, but the associationvaried by time period and gender. Between 1980 and 1995, Finnishmale smokers seem to have become more consistent in their unhealthybehaviour, while a corresponding trend was not observed amongwomen.     

Haemodynamics and Myocardial Oxygenation during Anaesthesia for Coronary Artery Surgery: Comparison between Enflurane and High-Dose Fentanyl Anaesthesia

Changes in central and coronary haemodynamics and myocardial oxygenation during anaesthesia induction, intubation, skin incision and sternotomy were studied in 24 patients undergoing a coronary artery bypass grafting operation under either high-dose fentanyl or enflurane anaesthesia. The anaesthesia induction caused no changes in the coronary haemodynamics in either group, in spite of a marked decrease in the coronary perfusion pressure during enflurane induction. In both groups a decrease in the coronary sinus blood flow and an increase in the coronary vascular resistance was observed after the intubation. At this stage, two patients in both groups had a low level of myocardial lactate extraction, indicating possible myocardial ischaemia; mean myocardial lactate extraction had decreased significantly from the awake level in both groups. A circulatory response to surgical stimulation was seen in both groups, although it could be somewhat better controlled during enflurane anaesthesia. In the enflurane patients the increase in myocardial oxygen demand was accompanied by increased coronary flow, while in the fentanyl group the increase in coronary flow was not in proportion to the increased oxygen demand, and an increase in myocardial oxygen extraction was also seen. During surgery, three fentanyl patients and one enflurane patient had a low level of myocardial lactate extraction.     

Complications Related to Permanent Pacemaker Therapy

This study evaluates complications related to permanent endocardial pacing in the era of modern pacemaker therapy. There is only limited information available about the complications related to modern cardiac pacing. Most of the existing data are based on the 1970s and are no longer valid for current practice. The recent reports on pacemaker complications are focused on some specific complication or are restricted to early complications. Thus, there are no reports available providing a comprehensive view of complications related to modern cardiac pacing. Four hundred forty-six patients, who received permanent endocardial pacemakers between January 1990 and December 1995 at Kuopio University Hospital, were reviewed retrospectively using patient records. Attention was paid to the occurrence of any complication during the implantation or follow-up. An early complication was detected in 6.7%, and 4.9% of patients were treated invasively due to the early complication. Late complication developed in 7.2% and reoperation was required in 6.3% of the patients. Complications related to the implantation procedure occurred in 3.1%. Inadequate capture or sensing was observed in 7.4% of the patients. Pacemaker infection was detected in 1.8% and erosion in 0.9% of the patients. An AV block developed in 3.6% (1.6%/year) patients who received an AAI(R)-pacemaker due to sick sinus syndrome. There was no mortality attributable to pacemaker therapy. A great majority (68%) of the complications occurred within the first 3 months after the implantation. Complications associated to modern permanent endocardial pacemaker therapy are not infrequent. Eleven percent of patients needed an invasive procedure due to an early or late complication.     

Haikko Declaration on actions for primary health care

An International Symposium on Health and Environment in DevelopingCountries was held in Haikko, Finland, in August 1986. It wasorganized by Finnish non-governmental organizations and supportedby international agencies and the Finnish government. Some 200health-related professionals from over 40 developing and developedcountries attended. One section was devoted to primary healthcare, and the discussions resulted in a five-point action programmeto accelerate progress towards Health for All by the year 2000.This programme was designated the Haikko Declaration. Noting that the Health for All movement is encountering difficultiesin many countries, the Declaration addresses the need for continuingpolitical support for the primary health care approach. Thisshould be backed up by a clearer identification of social inequalitiesin health and health care. In the face of a resurgence of ‘vertical’approaches in the international health arena, the Declarationreasserts the need for a broad social and intersectoral approachto health involving local decision-making; it calls on multilateralagencies and bilateral donors to support countries to developnational health systems based on primary health care, It alsoemphasizes the need for reforms in the world economy, whichis presently detrimental to Health for All. Internationallyimposed adjustment measures to repay foreign debts should notbe allowed to reverse a strategic social policy like primaryhealth care; rather actions should be taken to reverse deleteriousinternational economic policies. More funds need to be mobilizedfor health care, but the present fashion for user charges-whichtend to undermine Health for All-should be replaced by a greateremphasis on collective financing mechanisms. On the other handwastage of health resources is common, especially in hospitals,and the health system should pay for some of its primary healthcare developments out of efficiency savings. The views expressedrepresent the consensus reached in an international meetingand are published in Declaration form to promote discussionand action.     

INCREASED SERUM ACETATE AS A MARKER OF PROBLEM DRINKING AMONG DRUNKEN DRIVERS

727 consecutive drunken drivers were studied for laboratorymarkers of excessive alcohol consumption. Serum -glutamyltransferaseand alanine aminotransferase showed no differences and aspartateaminotransferase and blood alcohol concentration only smalldifferences between groups of first and repeating drunk drivingoffenders. The best laboratory test to differentiate the repeatingoffenders with probably more serious alcohol problems from thefirst offenders was in our material serum acetate, the meanserum acetate level of the repeating offenders being highlysignificantly (P<0.001) higher than that of the first offendersor nonalcoholic controls. Serum acetate also differentiatedfirst offenders from nonalcoholic controls (P<0.001). Ourresults suggest that serum acetate could be used for the screeningof problem drinking among drunken drivers.     

THE SPECIFICITY OF ANTI-HLA CLASS II MONOCLONAL ANTIBODIES IN CATTLE

At the Eleventh International HLA Histocompatibility Workshop, numerous anti-HLA class II monoclonal antibodies (mAb) were tested. For several of the polymorphic mAb, one epitope for binding has been mapped within the antigen-binding site of the class II molecules. Screening of the available bovine DRB3 and DQB exon 2 sequences revealed that some of the key amino acid (AA) motifs of these epitopes were present in cattle as well, and the question was raised whether this sharing of key AA motifs might cause interspecies cross-reactivity. Eight polymorphic anti-HLA class II mAb (seven anti-HLA DRB1 and one anti-HLA DQB) were selected for analysis of their reactivity towards bovine lymphocytes. In addition, the monomorphic anti-HLA class II mAb, 7.5.10.1, was selected for analysis, as this mAb was described to detect class II polymorphism in cattle. Flow cytometry and lymphocyte microcytotoxicity testing revealed that five of the polymorphic anti-HLA mAb were reactive with bovine lymphocytes. Furthermore, the anti-bovine reactivity of 7.5.10.1 was confirmed. These findings were supported by biochemical analysis. The anti-bovine reaction of the anti-HLA mAb did not correspond with the expected reaction, which was based on the presence of the AA, postulated to be responsible for recognition. Therefore, we suggest that the patterns of reactivity of the anti-HLA mAb are not always determined by one epitope.