Long-term neurological sequelae after decompression sickness in retired professional divers.

INTRODUCTION: Decompression sickness (DCS) has traditionally been categorized as type I DCS, affecting joints and skin, and type II affecting the nervous system. In the present study, we wanted to examine whether divers with a history of neurological DCS demonstrated a pattern of symptoms and clinical neurological and neurophysiological signs different from divers with other manifestations of DCS or no history of DCS. METHODS: Up to 1990, 365 Norwegian offshore divers worked in the North Sea. Two hundred and eight divers who had performed saturation diving, bounce diving or both, were included in this study. They filled in a questionnaire for registration of diving experience and health complaints, and episodes of DCS were registered. All participants had a clinical neurological and neurophysiological examination (ERP- P300). RESULTS: One hundred and sixty three of the 208 divers (78.4%) reported episodes of DCS. Neurological DCS was reported by 41 (19.7%) divers. Forty-five divers (21.6%) reported no episodes of DCS. Divers who reported episodes of DCS reported significantly more symptoms compared with divers who reported no DCS. Divers who reported neurological DCS had significantly more neurological findings on motility tests, sensory tests and coordination/cerebellar tests. The P300 motor reaction times were significantly longer in divers reporting DCS, but there was no significant difference between divers with neurological DCS and divers with other forms of DCS. CONCLUSIONS: This study indicates that DCS is associated with long-term effects on the nervous system independent of the symptomatology in the acute stage.

Mental health interventions by lay counsellors: a systematic review and meta-analysis.

OBJECTIVE: To investigate the effectiveness of community-based mental health interventions by professionally trained, lay counsellors in low- and middle-income countries. METHODS: We searched PubMed®, Cochrane Central Register of Controlled Trials, PROSPERO and EBSCO databases and professional section publications of the United States National Center for PTSD for randomized controlled trials of mental health interventions by professionally trained, lay counsellors in low- and middle-income countries published between 2000 and 2019. Studies of interventions by professional mental health workers, medical professionals or community health workers were excluded because there are shortages of these personnel in the study countries. Additional data were obtained from study authors. The primary outcomes were measures of post-traumatic stress disorder, depression, anxiety and alcohol use. To estimate effect size, we used a random-effects meta-analysis model. FINDINGS: We identified 1072 studies, of which 19 (involving 20 trials and 5612 participants in total) met the inclusion criteria. Hedges' g for the aggregate effect size of the interventions by professionally trained, lay counsellors compared with mostly either no intervention or usual care was -0.616 (95% confidence interval: -0.866 to -0.366). This result indicates a significant, medium-sized effect. There was no evidence of publication bias or any other form of bias across the studies and there were no extreme outliers among the study results. CONCLUSION: The use of professionally trained, lay counsellors to provide mental health interventions in low- and middle-income countries was associated with significant improvements in mental health symptoms across a range of settings.

Diving and long-term cardiovascular health.

BACKGROUND: Short-term cardiovascular effects from ambient pressure exposure are known. However, long-term cardiovascular effects from diving in humans have been less studied. AIMS: To examine possible long-term cardiovascular health effects from occupational diving. METHODS: We compared the prevalence of cardiovascular disease in former divers to non-divers. We obtained data on male former divers with a certificate valid for professional diving after 1980, from the Norwegian Diver 2011 project, and matched data on the general male population from the HUNT3 Survey. We also compared former divers with high and low grades of diving exposure. RESULTS: Data were available on 768 former divers. The prevalence of self-reported high blood pressure in former divers who often omitted a dive-free day after 3 days of strenuous diving was 28% compared with 18% in those who rarely violated these regulations [relative risk (RR) 1.47, confidence interval (CI) 1.01-2.15]. Also, the prevalence of myocardial infarction/angina pectoris was 11% in divers with >150 professional dives/year compared with 4% in divers with ≤50 professional dives/year [RR adj. 2.91 (CI 1.23-6.87)] and 16% in divers with >2000 air dives in total relative to 3% in divers with ≤2000 dives [RR adj. 3.05 (CI 1.47-6.34)]. CONCLUSIONS: The prevalence of some cardiovascular symptoms and diseases may be higher in male former divers than in the general population. Diving might have adverse long-term cardiovascular effects. Whether this is associated with diving per se or strenuous physical activity requires further studies.

Six years without pholcodine; Norwegians are significantly less IgE-sensitized and clinically more tolerant to neuromuscular blocking agents.

BACKGROUND: As a strong inducer of IgE antibodies to substituted ammonium ion epitopes (QAI), pholcodine (PHO) is a postulated cause of allergic anaphylaxis to neuromuscular blocking agents (NMBAs). Three years after withdrawal of PHO in Norway, a significant reduction in IgE sensitization and anaphylaxis reporting was seen. OBJECTIVE: Six-year follow-up study on the effects of PHO withdrawal on IgE sensitization and anaphylaxis reporting. METHODS: From 650 acute consecutive reports (2005-2013) to the Norwegian Network for Anaphylaxis under Anaesthesia (NARA), total number of reports on suspected anaphylactic reactions, number of reactions where NMBAs were administered, number of reactions where serum IgE antibodies (≥0.35 kUA /l) to suxamethonium (SUX) and PHO were present at time of reaction and anaphylaxis severity grades were retrieved. In addition, NMBA sales and prevalence of IgE sensitization to PHO and SUX among 'allergics' were monitored. RESULTS: From baseline period P0 (PHO on the market) through the first (P1) and second (P2), three-year periods after withdrawal, significant falls in total reports (P < 0.001) and reports with IgE antibodies to PHO (P = 0.008) and SUX (P = 0.001) at time of reaction were found. Total NMBA sales in P2 were 83% of P0, and SUX and rocuronium (ROC) together made up 86% of sales throughout the study. Five NMBA-related anaphylactic deaths occurred during P0 and P1 and, however, none during P2. Prevalence of IgE sensitization to SUX in 'allergics' fell to 0% at 4 and 5 years after withdrawal. CONCLUSIONS: Six years after PHO withdrawal, the Norwegian population has become significantly less IgE-sensitized and clinically more tolerant to NMBAs.

Pregnancy outcome in partners of male professional divers in Norway.

BACKGROUND: Diving is associated with both acute and long-term effects in several organ systems. Reduced semen quality after extreme diving and a reduced proportion of males in the offspring of divers have previously been reported. AIMS: To study pregnancy outcomes in partners of professional male divers. METHODS: The cohort of divers registered with the Norwegian Inshore Diving Registry was linked to the Medical Birth Registry of Norway (MBRN). RESULTS: In total, 6186 male divers had 10395 children registered in the MBRN during the study period. Of these, 52% were boys, compared to 51% in the general population. The partners of a subgroup of divers who were most likely to be occupationally exposed at the time of conception reported that early miscarriage was more frequent (27%) than in the general population (21%; relative risk 1.21, 95% confidence interval 1.05-1.39). Otherwise, there was a lower risk of adverse pregnancy outcomes such as preterm birth, stillbirth, low birthweight, small for gestational age and low Apgar score compared to the general population. Birthweight above 4000g was more frequent. CONCLUSIONS: We observed no reduced sex ratio in the offspring of occupational divers. Except for an increase in self-reported early miscarriage in the partners of exposed divers, we observed no excess risk of any of the adverse perinatal pregnancy outcomes studied.

Mortality among professional divers in Norway.

BACKGROUND: Diving operations are technically complex, and the underwater environment poses a high risk of fatal or near miss accidents. Furthermore, long-term effects of diving on bone, the central nervous system and the lung have been observed in divers who have not experienced any diving-related accidents. AIMS: To compare total and cause-specific mortality among Norwegian professional divers by class of diving certificate, relative to the general population. METHODS: Data on mortality were obtained for divers in the Norwegian Inshore Diving Registry, which comprises data on all divers with a certificate valid for professional diving after 1980. By August 2010, 5526 male divers born between 1950 and 1990 were identified, 3130 of whom were fully certified professional divers. The rest of the Norwegian male population born in the same period (1 604 147) served as referents. Data on mortality were obtained by linkage to the Cause of Death Registry. RESULTS: Mortality was 23 per 1000 in professional divers and 24 per 1000 in referents. The hazard ratio was 0.79 (confidence interval [CI] 0.63-0.997). Diving-related accidents and suicide were the most common causes of death among divers. Both were significantly more common among divers with the higher level diving certificates. CONCLUSIONS: Overall, mortality in professional divers was lower than that of the general population. However, professional divers had a higher risk of dying from work-related accident or suicide.

Can air pollution affect tear film stability? A cross-sectional study in the aftermath of an explosion accident.

BACKGROUND: After an explosion and fire in two tanks containing contaminated oil and sulphur products in a Norwegian industrial harbour in 2007, the surrounding area was polluted. This caused an intense smell, lasting until the waste was removed two years later. The present study reports examinations of tear film break up time among the population. The examinations were carried out because many of the people in the area complained of sore eyes. The purpose of the study was to assess the relationship between living or working close to the polluted area and tear film stability one and a half years after the explosion. METHODS: All persons working or living in an area less than six kilometres from the explosion site were invited to take part in the study together with a similar number of persons matched for age and gender living more than 20 kilometres away. Three groups were established: workers in the explosion area and inhabitants near the explosion area (but not working there) were considered to have been exposed, and inhabitants far away (who did not work in the explosion area) were considered to be unexposed. A total of 734 people were examined, and the response rate was 76 percent. Tear film stability was studied by assessing non-invasive break-up time (NIBUT) using ocular microscopy. In addition Self-reported Break Up Time (SBUT) was assessed by recording the time the subject could keep his or hers eyes open without blinking when watching a fixed point on a wall. Background information was obtained using a questionnaire. Non-parametric Wilcoxon-Mann-Whitney-tests with exact p-values and multiple logistic regression analyses were performed. RESULTS: Both NIBUT and SBUT were shorter among the male exposed workers than among the inhabitants both near and far away from the explosion area. This was also found for SBUT among males in a multiple logistic regression analysis, adjusting for age and smoking. CONCLUSIONS: Reduced tear film stability was found among workers in an area where an explosion accident had occurred.

IgE-sensitization to the cough suppressant pholcodine and the effects of its withdrawal from the Norwegian market.

BACKGROUND: IgE-mediated anaphylaxis to neuromuscular blocking agents (NMBA), frequent in Norway, was proposed to be caused by exposure to pholcodine (PHO) carrying the allergenic quarternary ammonium ion epitope. Consequently, the PHO-containing drug was withdrawn from the market in March 2007. OBJECTIVE: Describe the effects of withdrawal of PHO on IgE, IgE-antibodies and reported frequencies of anaphylaxis to NMBAs. METHODS: Three hundred sera from supposedly allergic patients sampled yearly through 2006 to 2010 were analysed for IgE antibodies to PHO, suxamethonium (SUX) and morphine (MOR). Furthermore, IgE and preliminary reports from the Norwegian Network for Anaphylaxis under Anaesthesia (NARA) were monitored. RESULTS: PHO exposure was associated with IgE sensitization to PHO, MOR and SUX. However, after withdrawal, within 1 year, antibody prevalences to PHO and SUX fell significantly from 11.0% to 5.0% and from 3.7% to 0.7%, respectively. At 3 years, SUX had fallen to 0.3%, PHO to 2.7% and MOR to 1.3%. By 2 years, the prevalence of elevated IgE was significantly reduced. After 3 years, the incidence of reported suspected anaesthetic anaphylaxis fell significantly, both the total number, the reactions related to NMBAs and those with IgE antibodies to SUX. CONCLUSIONS: Withdrawing of PHO lowered significantly within 1-2 years levels of IgE and IgE antibodies to PHO, MOR and SUX, and, within 3 years, the frequency of NMBA suspected anaphylaxis. The results strengthen the PHO hypothesis considerably and equally the need to question the existence of cough depressants containing PHO.

Suspected allergy to local anaesthetics: follow-up in 135 cases.

BACKGROUND: Local anaesthetics (LA) are generally considered safe with respect to allergy. However, various clinical reactions steadily occur. Even though most reactions are manifestations of reflexes to perceptive stimuli, uncertainty often remains regarding a possible allergic mechanism. This uncertainty later leads to an avoidance of local anaesthesia and unnecessarily painful interventions, resource-consuming general anaesthesia or even the risk of re-exposure to other yet unidentified allergens. In the present study, follow-up procedures at an allergy clinic were analysed to examine the frequency of identified causative agents and pathogenetic mechanisms and evaluate the strength of the diagnostic conclusions. METHOD: The medical records of 135 cases with alleged allergic reactions to LA were reviewed. Diagnoses were based on case histories, skin tests, subcutaneous challenge tests and in vitro IgE analyses. RESULTS: Two events (1.5%) were diagnosed as hypersensitivity to LA, articaine-adrenaline and tetracaine-adrenaline, respectively. Ten reactions (7%) were diagnosed as IgE-mediated allergy to other substances including chlorhexidine, latex, triamcinolone and possibly hexaminolevulinate. As challenge testing was not consistently performed with the culprit LA compound, follow-ups were short of definitely refuting hypersensitivity in 61% of the cases. The reported clinical manifestations were in general diagnostically unspecific, but itch and generalised urticaria were most frequent in test-positive cases. CONCLUSION: Reactions during local anaesthesia are rarely found to be an IgE-mediated LA allergy. Whenever the clinical picture is compatible with allergy, other allergens should also be tested.

National pholcodine consumption and prevalence of IgE-sensitization: a multicentre study.

BACKGROUND: The aim of this study was to test, on a multinational level, the pholcodine (PHO) hypothesis, i.e. that the consumption of PHO-containing cough mixtures could cause higher prevalence of IgE antibodies to PHO, morphine (MOR) and suxamethonium (SUX). As a consequence the risk of anaphylaxis to neuromuscular blocking agents (NMBA) will be increased. METHODS: National PHO consumptions were derived from the United Nations International Narcotics Control Board (INCB) database. IgE and IgE antibodies to PHO, MOR, SUX and P-aminophenyl-phosphoryl choline (PAPPC) were measured in sera from atopic individuals, defined by a positive Phadiatop test (>0.35 kU(A)/l), collected in nine countries representing high and low PHO-consuming nations. RESULTS: There was a significant positive association between PHO consumption and prevalences of IgE-sensitization to PHO and MOR, but not to SUX and PAPPC, as calculated both by exposure group comparisons and linear regression analysis. The Netherlands and the USA, did not have PHO-containing drugs on the markets, although the former had a considerable PHO consumption. Both countries had high figures of IgE-sensitization. CONCLUSION: This international prevalence study lends additional support to the PHO hypothesis and, consequently, that continued use of drugs containing this substance should be seriously questioned. The results also indicate that other, yet unknown, substances may lead to IgE-sensitization towards NMBAs.

Reproducibility of transcutaneous oximetry and laser Doppler flowmetry in facial skin and gingival tissue.

Laser Doppler flowmetry (LDF) and transcutaneous oximetry (TcPO(2)) are non-invasive techniques, widely used in the clinical setting, for assessing microvascular blood flow and tissue oxygen tension, e.g. recording vascular changes after radiotherapy and hyperbaric oxygen therapy. With standardized procedures and improved reproducibility, these methods might also be applicable in longitudinal studies. The aim of this study was to evaluate the reproducibility of facial skin and gingival LDF and facial skin TcPO(2). The subjects comprised ten healthy volunteers, 5 men, aged 31-68 years. Gingival perfusion was recorded with the LDF probe fixed to a custom made, tooth-supported acrylic splint. Skin perfusion was recorded on the cheek. TcPO(2) was recorded on the forehead and cheek and in the second intercostal space. The reproducibility of LDF measurements taken after vasodilation by heat provocation was greater than for basal flow in both facial skin and mandibular gingiva. Pronounced intraday variations were observed. Interweek reproducibility assessed by intraclass correlation coefficient ranged from 0.74 to 0.96 for LDF and from 0.44 to 0.75 for TcPO(2). The results confirm acceptable reproducibility of LDF and TcPO(2) in longitudinal studies in a vascular laboratory where subjects serve as their own controls. The use of thermoprobes is recommended. Repeat measurements should be taken at the same time of day.

Airway inflammation and bronchial remodelling in toluene diisocyanate-exposed BALB/c mouse model.

UNLABELLED: Toluene diisocyanate (TDI), a highly reactive industrial chemical, is one of the leading causes of occupation-related asthma in industrialized countries. The pathogenesis of TDI-induced asthma, however, remains not fully understood, in part due to lack of appropriate animal models. Twenty five female BALB/c mice (age: 8 weeks) were randomly divided into 5 groups: Ovabumin (OVA); OVA peptide amino acid residues No. 323-339 (Pep); TDI; alum and physiological saline. Mice were intraperitoneally injected with 25 microg OVA or pep absorbed on 300 microg alum, 300 microg alum or saline on days 0, 7 and 14. For the TDI group, mice were sensitized subcutaneously with 20 microl neat TDI on day 0; 20 microl of TDI in olive oil (1:10) on days 7 and 14; on days 21-23. Then each group was challenged intranasally with 20 microl of 1% OVA, 1% Pep, 1% TDI, 10% alum and saline respectively. On day 28, mice were killed under pentothal anesthesia. The results demonstrated that neutrophil-dominant inflammation with a few eosinophil infiltration occurred in the peri-bronchial and peri-vascular regions of the lungs. This was accompanied by hyperplasia/hypertrophy of cells lining the airways and mucus production as shown by HE staining. Positive immunohistochemical MBP staining in parenchyma was also shown. Th2 cytokine IL-4 and IgE production were significant increased 5 days after last challenge while IFN-gamma level was below the detection limit. CONCLUSION: the clear elevation of IL-4 and IgE could allow to conclude a possible Th2-like dominated allergic response in TDI-exposed BALB/c mouse model.

Risk of birth defects by parental occupational exposure to 50 Hz electromagnetic fields: a population based study.

OBJECTIVES: To study the risk of birth defects by parental occupational exposure to 50 Hz electromagnetic fields. METHODS: The Medical Birth Registry of Norway was linked with census data on parental occupation. An expert panel constructed a job exposure matrix of parental occupational exposure to 50 Hz magnetic fields. Exposure to magnetic fields was estimated by combining branch and occupation into one of three exposure levels: <4 hours, 4-24 hours, and >24 hours/week above approximately 0.1 mu T. Risks of 24 categories of birth defects were compared across exposure levels. Out of all 1.6 million births in Norway in the period 1967-95, 836,475 and 1,290,298 births had information on maternal and paternal exposure, respectively. Analyses were based on tests for trend and were adjusted for parents' educational level, place of birth, maternal age, and year of birth. RESULTS: The total risk of birth defects was not associated with parental exposure. Maternal exposure was associated with increased risks of spina bifida (p=0.04) and clubfoot (p=0.04). A negative association was found for isolated cleft palate (p=0.01). Paternal exposure was associated with increased risks of anencephaly (p=0.01) and a category of "other defects" (p=0.02). CONCLUSION: The present study gives an indication of an association between selected disorders of the central nervous system and parental exposure to 50 Hz magnetic fields. Given the crude exposure assessment, lack of comparable studies, and the high number of outcomes considered, the results should be interpreted with caution.

Plasmapheresis in the treatment of steroid-dependent bronchial asthma.

BACKGROUND: Can plasmapheresis improve disease severity and lung function and reduce steroid doses in severe asthma patients dependent on oral corticosteroids? METHODS: A pilot study with four asthma patients was undertaken using PEF (peak expiratory flow) symptom score, number of puffs of beta2-agonist, and dose of systemic steroids as disease variables. After at least an 8-week run-in, the patients were randomized to a crossover treatment regimen consisting of either 10 days of plasmapheresis or placebo treatment. Each treatment was succeeded by an 8-26-week follow-up period. RESULTS: No patients achieved a significant effect of plasmapheresis treatment according to the established criteria, nor did anyone experience deterioration. CONCLUSIONS: Removing humoral factors extensively over a 10-day period did not significantly influence the clinical condition of the four steroid-dependent asthma patients studied. Circulating humoral factors seem to be of little importance for the maintenance of the established chronic allergic inflammation in these patients. Plasmapheresis does not seem to be a treatment option for this patient category.

[Exposure therapy for anxiety disorders in a psychiatric ward]. / Eksponeringsbehandling for angstlidelser i en psykiatrisk avdeling.

Exposure treatment is efficient as a treatment for some anxiety disorders. Briefly described, it consists in letting the patient expose himself to an anxiety-inducing situation without running away from it. In the author's experience, this mode of treatment is too seldom used. This article exemplifies conditions in which this form of therapy can be useful. The method is easily learnt by general practitioners. The article describes the treatment of five patients with these psychiatric diagnoses: agoraphobia, social phobia, compulsive disorder, and post-traumatic stress disorder.

Birth defects and paternal occupational exposure. Hypotheses tested in a record linkage based dataset.

UNLABELLED: MAIN QUESTION: To test previously established hypotheses on associations of birth defects with paternal occupation on the basis of a Norwegian registry material. METHODS: The study comprised all births in Norway 1970 -1993 for which linkage with population censuses 1970, -80 and -90 on parents' job title could be obtained--about 1 million births (75% all births). The reference population was offspring of the group that did not belong to the actual occupation. RESULTS: Vehicle mechanics had an association with hypospadias--OR 5.19 (CI 1.31-14.24), painters had a non-significant association with spina bifida--OR 2.03 (CI 0.99-3.75) and printers with club foot--OR 1.61 (CI 0.89-2.90). Associations observed previously in off-spring of fathers in large occupational groups such as teachers, drivers, electricity related occupations, sales related occupations and agricultural workers were not confirmed in this dataset. CONCLUSIONS: The study gave further evidence of cause effect relationships in the confirmed positive associations, though without any clarification of possible mechanisms involved. Possible false negative findings might be caused by low statistical power due to small occupational groups or non-differential misclassification of exposure.

The effect of male occupational exposure in infertile couples in Norway.

The objective of the study was to assess whether reduced semen quality in infertile couples is associated with occupational exposures known to be hazardous to fertility. Results of the first semen analysis were linked to occupational exposure data from a self-administered questionnaire. Reduced semen quality was found in men exposed to electromagnetic fields (odds ratio, 3.22; confidence interval, 1.46 to 7.09). A tendency toward reduced semen quality was seen in commuters (OR, 1.52; CI, 0.89 to 2.59), shift workers (OR, 1.46; CI, 0.89 to 2.40), and men exposed to heavy metals (OR, 1.47; CI, 0.76 to 2.87). In general, the impact of occupational exposure on semen quality in infertile couples in Norway seemed to be minor. However, occupational exposure mapping is still important in individual infertility investigations.

Secular trends in sperm variables for groups of men in fertile and infertile couples.

OBJECTIVE: To assess possible secular trends in sperm variables in men according to previous or subsequent paternity. DESIGN: A comparison of secular trends in sperm variables 1975-1994 in men under investigation for infertility in groups according to previous and subsequent paternity, based on data from the Medical Birth Registry of Norway. SETTING: University hospital, Sperm laboratory and the Medical Birth Registry of Norway. MATERIAL: Samples were obtained from: 1108 men who had fathered at least one child before the analysis. 1786 men who had at least one child after the analysis, and 2286 men with no children registered. MAIN OUTCOME MEASURES: Sperm concentration, seminal fluid volume, total number of spermatozoa per ejaculate. RESULTS: Analyzed by year of evaluation, men with no child registered had a significant secular decrease of sperm concentration, total number of sperms per ejaculate and seminal volume. The group with subsequent children had significant secular decrease of sperm concentration and total sperm count per ejaculate, while no significant changes were found for the group with previous children. Analyzed by year of birth, a significant decrease of sperm concentration and total sperm count was found for the group without and for the group with subsequent children. CONCLUSION: The results are compatible with a cohort effect, exhibiting a trend of deteriorating sperm variables in consecutive birth cohorts.

Reproductive outcome in offspring of parents occupationally exposed to lead in Norway.

In Norway, great efforts have been made to protect both male and female employees against teratogenic exposures. Associations between occupational lead exposure and reproductive outcome in the offspring were studied. All births in Norway 1970-1993 with possible maternal or paternal occupational lead exposure were compared with a reference population of offspring of parents without occupational lead exposure. Offspring of lead exposed mothers had an increased risk of low birth weight (RR = 1.34; CI = 1.12-1.60) and neural tube defects (RR = 2.87; CI = 1.05-6.38). Effects on birth weight and gestational age showed significant dose-response associations. Offspring of lead exposed fathers had no increased risks of any of the analyzed reproductive outcomes. However, decreased risks were observed of low birth weight (RR = 0.91; CI = 0.86-0.96) and preterm birth (RR = 0.89; CI = 0.86-0.93). Further efforts seem to be needed to protect the offspring of lead-exposed mothers.