Managerial leadership and ischaemic heart disease among employees: the Swedish WOLF study

Objective:

To investigate the association between managerial leadership and ischaemic heart disease (IHD) among employees.

Methods:

Data on 3122 Swedish male employees were drawn from a prospective cohort study (WOLF). Baseline screening was carried out in 1992–1995. Managerial leadership behaviours (consideration for individual employees, provision of clarity in goals and role expectations, supplying information and feedback, ability to carry out changes at work successfully, and promotion of employee participation and control) were rated by subordinates. Records of employee hospital admissions with a diagnosis of acute myocardial infarction or unstable angina and deaths from IHD or cardiac arrest to the end of 2003 were used to ascertain IHD. Cox proportional-hazards analyses were used to calculate hazard ratios for incident IHD per 1 standard deviation increase in standardised leadership score.

Results:

74 incident IHD events occurred during the mean follow-up period of 9.7 years. Higher leadership score was associated with lower IHD risk. The inverse association was stronger the longer the participant had worked in the same workplace (age-adjusted hazard ratio 0.76 (95% CI 0.61 to 0.96) for employment for 1 year, 0.77 (0.61 to 0.97) for 2 years, 0.69 (0.54 to 0.88) for 3 years, and 0.61 (0.47 to 0.80) for 4 years); this association was robust to adjustments for education, social class, income, supervisory status, perceived physical load at work, smoking, physical exercise, BMI, blood pressure, lipids, fibrinogen and diabetes. The dose–response association between perceived leadership behaviours and IHD was also evident in subsidiary analyses with only acute myocardial infarction and cardiac death as the outcome.

Conclusion:

If the observed associations were causal then workplace interventions should focus on concrete managerial behaviours in order to prevent IHD in employees.

Time- and dose-related regional fluxes of tissue-type plasminogen activator in anesthetized endotoxemic pigs

BACKGROUND

Acute endotoxinemia elicits an early fibrinolytic response. This study analyzes the effects of the dose and duration of endotoxin infusion on arterial levels of tissue-type plasminogen activator (tPA) and pulmonary, mesenteric and hepatic plasma tPA fluxes.

METHODS

Pigs were randomized to receive an acute, high-dose (for 6 h, n=13, high ETX) or a prolonged, low-dose (for 18 h, n=18, low ETX) infusion of endotoxin or saline vehicle alone (for 18 h, n=14, control). All animals were fluid resuscitated to maintain a normodynamic circulation. Systemic and regional blood flows were measured and arterial, pulmonary arterial, portal and hepatic venous blood samples were analyzed to calculate regional net fluxes of tPA. Plasma tumor necrosis factor (TNF-alpha) levels were analyzed.

RESULTS

Mesenteric tPA release and hepatic uptake increased maximally at 1.5 h in ETX groups related to dose. Maximal mesenteric tPA release [high ETX 612 (138-1185) microg/min/kg, low ETX 72 (32-94) microg/min/kg, median+/-interquartile range] and hepatic tPA uptake [high ETX -1549 (-1134 to -2194) microg/min/kg, low ETX -153 (-105 to -307) microg/min/kg] correlated to TNF-alpha levels. Regional tPA fluxes returned to baseline levels at 6 h in both ETX groups and also remained low during sustained low ETX. No changes were observed in control animals.

CONCLUSIONS

Endotoxemia induces an early increase in mesenteric tPA release and hepatic tPA uptake related to the severity of endotoxemia. The time patterns of changes in mesenteric and hepatic tPA fluxes are similar in acute high-dose endotoxemia and sustained low-dose endotoxemia.

Pulmonary net release of tissue-type plasminogen activator during porcine primary and secondary acute lung injury

BACKGROUND

Tissue-type plasminogen activator (tPA) is a key mediator of fibrinolysis. Matching of pulmonary perfusion and ventilation is a critical denominator of oxygenation in acute lung injury (ALI). This study investigates pulmonary venoarterial plasma tPA gradients in association with acute ALI induced by bronchoalveolar lavage (BAL) and endotoxinemia (ETX).

METHODS

Twenty-one anaesthetized, ventilated pigs were allocated to control (CTRL, n=5), bronchoalveolar saline lavage (BAL, n=8) or infusion of Escherichia coli endotoxin (ETX, n=8). Total tPA was analyzed in plasma (ELISA calibrated for porcine tPA). The inflammatory response was assessed by TNFa levels (ELISA). All variables were assessed at baseline and 2 h following ALI.

RESULTS

Bronchoalveolar lavage and ETX induced similar increases in pulmonary shunt whereas pulmonary vascular resistance was significantly more increased in ETX animals. Cardiac output remained stable in BAL animals but decreased in ETX animals. The pulmonary venoarterial tPA plasma gradient increased in ETX animals, yielding a positive pulmonary net flux of tPA, which was absent in BAL animals. TNFalpha levels increased in ETX, but not in BAL, animals. A significant correlation was observed between TNFalpha and tPA plasma levels in ETX animals. All variables remained unchanged in CTRL animals.

CONCLUSION

Plasma changes of tPA levels support a pulmonary release of tPA in early experimental ALI induced by acute ETX but not lavage, and are related to the inflammatory response. Despite increased vascular fibrinolytic capacity in ETX animals, pulmonary dysfunction was not different from BAL animals. The results demonstrate the close relation between inflammation and coagulation in early ALI.

Regionally differentiated fibrinolytic responses during volume-resuscitated acute endotoxemia in pigs

BACKGROUND

Microcirculatory dysfunction and formation of microthrombi are common in sepsis as a result of a procoagulant state. A profibrinolytic change has however, been reported in early sepsis. This study investigates systemic and regional (pulmonary, preportal, hepatic, renal) fibrinolytic capacity as mirrored by fluxes of tissue-type plasminogen activator (t-PA) in response to acute endotoxemia and volume resuscitation.

METHODS

Eight anaesthetized, ventilated pigs (24-29 kg) were instrumented for systemic and regional haemodynamic monitoring. Aortic, pulmonary arterial, portal, hepatic and renal venous blood samples were collected. Following baseline stabilisation, Escherichia coli endotoxin was infused for 120 min. During the last 30 min of infusion, volume resuscitation was initiated targeting baseline cardiac output, and animals were observed for 3 h. Total tPA was analyzed by ELISA calibrated for porcine tPA. Net organ tPA fluxes were calculated based on in/outflowing plasma concentrations and regional blood flows.

RESULTS

Preportal release and hepatic extraction of tPA was observed at baseline. Pulmonary and renal net fluxes of tPA were not significantly different from zero. Endotoxemia increased plasma tPA levels in all investigated vascular beds. Preportal tPA release increased approximately 10-fold and hepatic extraction increased approximately 12-fold in non-resuscitated acute endotoxemia. No significant changes in pulmonary or renal tPA fluxes were observed. Volume resuscitation restored net fluxes to baseline values while plasma levels remained elevated approximately twofold compared with baseline.

CONCLUSION

Acute endotoxemia induces a prompt, marked and regionally differentiated pro-fibrinolytic response that cannot be discerned based on systemic levels of circulating tPA and that was normalized during volume resuscitation.

Sixteen years age limit for learner drivers in Sweden--an evaluation of safety effects

Through a reform implemented in Sweden, September 1993, the age limit for practising car driving was lowered from 17 1/2 to 16 years while the licensing age remained 18. The purpose of lowering the age limit was to give the learner drivers an opportunity to acquire more experience as drivers before being allowed to drive on their own. The primary aim of this study was to evaluate the effect of the reform in terms of accident involvement and data were therefore obtained from the national register of police reported accidents. The results show that after the reform there was a general reduction in the accident risk (accidents per 10 million km) of novice drivers with approximately 15%. Additional analyses show that the reduction of accident risk in the group who utilised the new age limit was approximately 40%, whereas those who did not utilise the prolonged training period did not benefit at all. Between 45 and 50% of the age population were found to utilise the reform. The accident reduction does not seem to be just an initial first year effect since the results were similar over 3 years of novice drivers during their first 2 years with a licence. These results suggest that the reform has been beneficial for the safety of novice drivers in Sweden. The results also suggest a potential for additional safety improvements if more young learner drivers can be brought to utilise the low age limit.

Nursing load in different care alternatives in Sweden during 18 years

In a repeated cross-sectional study, changes in nursing load and changes in care organisation (1978-1996) were studied in Sundsvall, Sweden. A total of 4555 nursing load measurements on elderly people were performed on four occasions (1978, 1988, 1993 and 1996). The nursing load has increased considerably at the nursing homes and at the homes for the aged during the whole period. In home care, the nursing load did not increase between 1978 and 1993, but it increased considerably between 1993 and 1996. The mean age of the residents, the number of persons with dementia, as well as the mean age, also increased. Between 1978 and 1996, the number of institutional resources decreased by 38%, while home care resources increased by 421%. The considerable increase in nursing load presents a worrying scenario when it is combined with the expected increase of the oldest old.

Corynebacterium sundsvallense sp. nov., from human clinical specimens

Three strains of a previously undescribed catalase-positive non-lipophilic coryneform bacterium isolated from human clinical specimens were characterized by phenotypic and molecular taxonomic methods. Morphologically the unknown bacterium consisted of pleomorphic rods, some of which displayed bulges/knobs at their ends. All three strains were similar in that they produced acid from fructose, glucose, maltose and sucrose and were urease-positive. Chemotaxonomic investigations revealed the presence of meso-diaminopimelic acid and short-chain mycolic acids consistent with the genus Corynebacterium sensu stricto. Comparative 16S rRNA gene sequencing showed that the three strains are genealogically highly related and constitute a new subline within the genus Corynebacterium, displaying > 3% sequence divergence with recognized species. The unknown bacterium was distinguished from currently validly published Corynebacterium species by phenotypic tests, including electrophoretic analysis of whole-cell proteins. Based on phylogenetic and phenotypic evidence, it is proposed that the unknown bacterium from clinical specimens be classified as Corynebacterium sundsvallense sp. nov. The type strain is CCUG 36622T.

Distinct delta T cell receptor repertoires in monozygotic twins concordant for coeliac disease

One of the hallmarks of coeliac disease, both active and treated, is an increased number and proportion of gamma/delta intraepithelial T lymphocytes in the small intestinal mucosa, and an increased number of gamma/delta T cells in the small intestinal mucosa of coeliac disease patients has been associated with the inheritance of specific HLA class II DQ alleles. Nonetheless, the contribution of genetic factors to the development of the T cell receptor (TCR) delta repertoire in coeliac disease is not known. We have assessed the contribution of genetic factors to development of the TCR delta repertoire in coeliac disease, by characterizing the junctional diversity of TCR delta transcripts expressed in the intestine and peripheral blood of a pair of monozygotic (MZ) twins concordant for coeliac disease. TCR Vdelta1, Vdelta2 and Vdelta3 transcripts from small intestinal and colon biopsies, and from peripheral blood mononuclear cells, were amplified by polymerase chain reaction (PCR) and the complementarity determining region (CDR)3 domains of TCR delta transcripts were analysed by denaturing PAGE and direct nucleotide sequencing. The repertoire of TCR delta transcripts and CDR3 amino acid motifs in the intestine and peripheral blood of MZ twins concordant for coeliac disease exhibited no overlap. The TCR delta repertoire in each twin was oligoclonal, and complexity of the junctional regions of their TCR delta transcripts was typical of the repertoire in healthy adults. Thus, genetically identical individuals with coeliac disease have distinct, non-overlapping TCR delta repertoires. Moreover, genetic factors that determine disease susceptibility do not appear to select for specific TCR delta sequences or CDR3 amino acid motifs.

Increased proinflammatory cytokine gene expression in the colonic mucosa of coeliac disease patients in the early period after gluten challenge

Activation of T cells in the intestinal mucosa in response to gluten exposure is thought to play a key role in the pathogenesis of coeliac disease. Moreover, the response of the rectal mucosa to gluten challenge has been considered a useful predictor of gluten sensitivity in coeliac disease. In the present study, we assessed early changes in the expression of proinflammatory cytokine genes and the T cell receptor (TCR) Vbeta repertoire in the rectal mucosa of coeliac disease patients following experimental gluten challenge. Cytokine gene expression was assessed in rectal mucosal biopsies from coeliac disease subjects and controls before and after rectal gluten challenge using quantitative reverse transcription polymerase chain reaction analysis, and the TCR Vbeta repertoire was characterized using a multiprobe RNase protection assay. Marked up-regulation of expression of the C-X-C chemokine IL-8, the proinflammatory cytokine IL-1beta, and the C-C chemokine monocyte chemotactic protein-1 occurred within 24 h of rectal gluten challenge in coeliac disease subjects, but not in controls. Furthermore, these changes occurred in the absence of parallel changes in the expressed repertoire of TCR Vbeta genes in the rectal mucosa. Thus, an increased expression of proinflammatory cytokine genes precedes the expansion of antigen-specific T cell populations in the early period following experimental exposure of the rectal mucosa of coeliac disease patients to gluten. These findings provide new insights into pathways that may be involved in the activation or reactivation of coeliac disease.

Cyclophosphamide-induced acute liver failure requiring transplantation in a patient with genetically deficient debrisoquine metabolism: a causal relationship?

Severe liver damage can occur after treatment with cyclophosphamide. The possible linkage to genetically deficient drug metabolic capacity is unknown. A 58-year-old woman with rheumatoid arthritis was treated with oral cyclophosphamide 50 mg twice daily for 2 months. Due to poor response the dose was doubled and liver failure requiring transplantation developed within weeks. After surgery PCR amplification using DNA from leukocytes showed that she was homozygous for the mutated allele CYP2D6B, which is predictive of the poor metaboliser phenotype for debrisoquine, occurring in 7% of Caucasians. Our patient may have accumulated high levels of the hepatotoxic 4-hydroxylated cyclophosphamide metabolite. Pharmacogenetic methods can help in exploring mechanisms of unexpected severe adverse effects.

Oral budesonide versus prednisolone in patients with active extensive and left-sided ulcerative colitis

BACKGROUND & AIMS

Systemic glucocorticosteroids (GCSs) have proven efficacy in active ulcerative colitis but cause undesired systemic side effects. Therefore, new GCSs with high topical activity and a high rate of metabolism may be of clinical value in this condition. The aim of this study was to explore the efficacy and safety of the topically acting GCS budesonide in an oral controlled-release formulation in extensive or left-sided, mild to moderately active ulcerative colitis.

METHODS

A 9-week, randomized, double-blind, controlled trial was performed, and treatments with 10 mg budesonide or 40 mg prednisolone daily, both gradually tapered, were compared. Endoscopic improvement and effect on endogenous plasma cortisol were assessed.

RESULTS

Thirty-four patients were administered budesonide, and 38 patients were administered prednisolone. Mean endoscopic scores improved significantly in both groups but without difference between the groups. Five patients in the budesonide group and 7 patients in the prednisolone group deteriorated and were withdrawn from the study. Morning plasma cortisol levels were suppressed in the prednisolone group (entry, 449 nmol/L; 2 weeks, 116 nmol/L; 4 weeks, 195 nmol/L) but were unchanged in the budesonide group.

CONCLUSIONS

The GCS budesonide administered in an oral controlled-release formulation seems to give an overall treatment result in active ulcerative colitis approaching that of prednisolone but without suppression of plasma cortisol levels. This concept merits further evaluation.

A novel multiple dose powder inhaler. Salbutamol powder and aerosol give equal bronchodilatation with equal doses

Twenty adult patients with stable asthma were treated with cumulatively increasing doses of salbutamol delivered from a metered dose inhaler (MDI) and from a novel multiple dose powder inhaler (MDPI), Easyhaler, in a randomized 3-period crossover study. Four doses of salbutamol (delivered doses to the patient: 90, 90, 180, 360 micrograms; cumulative dose of 720 micrograms) were administered during each of the three study days and were inhaled every 30 minutes. Drug doses were released from the powder inhaler either before or during inhalation. Spirometry was performed at the beginning of each study day and 20 minutes after each dose. The lung function parameters after cumulative dosing of salbutamol were equal during each study day. The maximal percentage changes in forced expiratory volumes in one second after 720 micrograms of salbutamol were 24% with the MDI and 23% and 24% with the Easyhaler inhaler, respectively. Ten patients reported mild side effects when using the MDI, three when the powder was released before inhalation and five when the MDPI was actuated during inhalation. No significant changes in heart rate or blood pressure were observed during the study. We conclude that the novel multiple dose powder inhaler is clinically equally effective and slightly better tolerated than conventional metered dose inhaler when equal doses of salbutamol are inhaled by asthmatic patients.

Theoretical aspects of detection of bacteraemia as a function of the volume of blood cultured

Clinically significant bacteraemia in adults is characterized by low numbers of circulating bacteria. Assuming a Poisson or a binomial distribution we have calculated the probability of detecting bacteria as a function of the concentration in blood, estimated the concentration of bacteria in blood from a given test result, and calculated the blood volume required to detect bacterial growth with a probability of 95% at a given mean number of colony-forming units (cfu) per sample unit. These theoretical assumptions have been used on an empirical population of patients with proven bacteraemia.

RESULTS

18% of Staphylococcus aureus bacteraemias and 29% of Escherichia coli bacteraemias have circulating bacteria with an estimated spread of less than 0.04 cfu/ml. With a 95% probability of detection of a bacteraemia, a concentration in blood corresponding to 3 cfu/sampling unit is necessary. In our empirical material, where 30 ml was cultured, the probability of detection of E. coli bacteraemias would have decreased by 11% if 20 ml had been cultured, and 27% if only 10 ml had been cultured. The corresponding figures for S. aureus were 6% and 15%, respectively. For low grade E. coli bacteraemias (< 0.04 cfu/ml) the decrease would have been 33% and 67%, respectively.

Serum hyaluronan and aminoterminal propeptide of type III procollagen in primary biliary cirrhosis: relation to clinical symptoms, liver histopathology and outcome

Hyaluronan (HA) and aminoterminal propeptide of type III procollagen (PIIINP), two biochemical connective tissue markers, were determined in 76 patients with primary biliary cirrhosis (PBC). The HA and PIIINP concentrations were significantly increased compared with controls (P less than 0.001). Both HA and PIIINP levels correlated significantly with conventional liver-function tests. All patients with stage IV PBC showed increased concentrations of both these variables. However, HA was a better marker with regard to prediction of development of cirrhosis as well as prediction of symptoms. Furthermore, HA also showed a negative correlation with time of survival (P less than 0.05). The present data indicate that HA is a more sensitive marker of liver damage in PBC than PIIINP.

Defective Fc receptor-mediated clearance in patients with primary biliary cirrhosis

Fc receptor-mediated clearance of immunoglobulin G-coated autologous erythrocytes was studied in patients with primary biliary cirrhosis (n = 14), alcoholic liver cirrhosis (n = 5) and healthy reference individuals (n = 14). The mean half-life of the sensitized erythrocytes was significantly prolonged in patients with primary biliary cirrhosis (85 +/- 25 minutes; P less than 0.001) compared with the corresponding value in patients with alcoholic cirrhosis (16 +/- 2 minutes) and healthy reference individuals (20 +/- 5 minutes), respectively. No correlation between clearance rate and age, liver histopathology, or serum levels of bilirubin, aminotransferases, immunoglobulin G, immunoglobulin A, and Clq binding or C3-containing immune complexes was found. The results presented here indicate a profound disturbance of Fc receptor-mediated immune clearance function in patients with primary biliary cirrhosis.

Blood and liver-infiltrating lymphocytes in primary biliary cirrhosis: increase in activated T and natural killer cells and recruitment of primed memory T cells

We used two-color and three-color flow cytometric analysis to study phenotypical activation and functional subsets of T and natural killer cells in the blood and liver tissue of patients with primary biliary cirrhosis, other chronic liver diseases and the blood of healthy subjects. The changes in blood lymphocyte phenotype in patients with primary biliary cirrhosis and other chronic liver diseases were similar and comprised elevated relative or absolute numbers of activated human leukocyte antigen-DR + T subset (CD4+ and CD8+) cells and DR+ natural killer-like (CD16+) cells. B cell (CD19+) numbers were normal. In primary biliary cirrhosis a selective reduction in T cells of suppressor-inducer (CD45RA + CD4 + ) type was registered. The human leukocyte antigen-DR expression among CD4+ T cell subsets was investigated further in primary biliary cirrhosis and healthy controls using triple antibody flow cytometric analysis. Phenotypical cell activation was confined to helper T cells of the primed, memory (CD45RO + CD4+) type. The decrease in suppressor-inducer T cells in primary biliary cirrhosis was paralleled by a reciprocal increase in primed memory T cells. Several significant differences were observed when blood and liver-infiltrating cells from primary biliary cirrhosis patients were compared. In the liver tissue, the CD4/CD8 ratio was decreased, the relative activation of T-subset cells and NK cells was further increased, the suppressor-inducer T subset was further depressed and the primed memory T subset was increased. The cytotoxic T-cell subset (CD11b-) dominated within the CD8+ population. In liver tissue from other chronic liver disease subjects, a lower CD4/CD8 ratio was found compared with primary biliary cirrhosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Guidelines for description of immunoassay kits

A provisional recommendation in order to improve manufacturers' and marketers' information to users of immunoassay kits has been compiled by a Nordic Clinical Chemistry project working group.