Updated assessment of occupational safety and health hazards of climate change.

Workers, particularly outdoor workers, are among the populations most disproportionately affected by climate-related hazards. However, scientific research and control actions to comprehensively address these hazards are notably absent. To assess this absence, a seven-category framework was developed in 2009 to characterize the scientific literature published from 1988-2008. Using this framework, a second assessment examined the literature published through 2014, and the current one examines literature from 2014-2021. The objectives were to present literature that updates the framework and related topics and increases awareness of the role of climate change in occupational safety and health. In general, there is substantial literature on worker hazards related to ambient temperatures, biological hazards, and extreme weather but less on air pollution, ultraviolet radiation, industrial transitions, and the built environment. There is growing literature on mental health and health equity issues related to climate change, but much more research is needed. The socioeconomic impacts of climate change also require more research. This study illustrates that workers are experiencing increased morbidity and mortality related to climate change. In all areas of climate-related worker risk, including geoengineering, research is needed on the causality and prevalence of hazards, along with surveillance to identify, and interventions for hazard prevention and control.

[COVID-19 and severe mental illness, especially in clozapine use]. / COVID-19 en ernstige psychiatrische aandoeningen, in het bijzonder bij clozapinegebruik.

BACKGROUND: The Clozapine Plus Working Group is frequently consulted for advice on measures in case of infection with SARSCoV-2 and on vaccination against COVID-19 in patients receiving clozapine.

AIM: Inform about risks of infection with SARS-CoV-2 in patients with severe mental illness (SMI), patients with schizophrenia spectrum disorders (SSD), and patients treated with clozapine. Advise on monitoring of clozapine plasma levels and white blood cell count and differential in COVID-19 and after vaccination, as well as measures to be taken.

METHOD: Literature research and case studies.

RESULTS: SMI patients and in particular SSD patients have an increased risk of infection with SARS-CoV-2 with more hospitalizations and higher mortality than non-psychiatric patients. Patients using clozapine may be at greater risk of infection. SARS-CoV-2 infection may cause a dangerous increase of clozapine plasma levels and generally mild and short-term granulocytopenia and lymphocytopenia, which are usually not a result of clozapine treatment.

CONCLUSION: In case of COVID-19 extra alertness is required in patients with SMI and especially SSD. In clozapine users, in case of COVID-19, reduction in dose by half to three quarters of the original dose is recommended. When patients develop granulocytopenia, SARS-CoV-2 should be considered as the cause and not immediately clozapine. SMI patients and clozapine users in particular belong to a high risk group with a medical indication for early vaccination.

Delegating Clozapine Monitoring to Advanced Nurse Practitioners: An Exploratory, Randomized Study to Assess the Effect on Prescription and Its Safety.

To test whether: (1) psychiatrists will prescribe clozapine more often if they can delegate the monitoring tasks to an advanced nurse practitioner (ANP), (2) clozapine monitoring by an ANP is at least as safe as monitoring by a psychiatrist. Patients from 23 Dutch outpatient teams were assessed for an indication for clozapine. ANPs affiliated to these teams were randomized to Condition A: clozapine monitoring by an ANP, or Condition B: monitoring by the psychiatrist. The safety of monitoring was evaluated by determining whether the weekly neutrophil measurements were performed. Staff and patients were blinded regarding the first hypothesis. Of the 173 patients with an indication for clozapine at baseline, only seven in Condition A and four in Condition B were prescribed clozapine (Odds Ratio = 2.24, 95% CI 0.61-8.21; p = 0.225). These low figures affected the power of this study. When we considered all patients who started with clozapine over the 15-month period (N = 49), the Odds Ratio was 1.90 (95% CI 0.93-3.87; p = 0.078). With regard to the safety of the monitoring of the latter group of patients, 71.2% of the required neutrophil measurements were performed in condition A and 67.3% in condition B (OR = 0.98; CI = 0.16-3.04; p = 0.98). Identifying patients with an indication for clozapine does not automatically lead to improved prescription rates, even when an ANP is available for the monitoring. Clozapine-monitoring performed by an ANP seemed as safe as that by a psychiatrist.

[Reactions on 'The effectiveness of monoamine oxidase inhibitors in treatment-resistant depressive disorders in clinical practice; a retrospective open-label study']. / Reacties op: 'De effectiviteit van monoamineoxidaseremmers bij therapieresistente depressie in de klinische praktijk; een retrospectieve openlabelstudie'.

Reactions on 'The effectiveness of monoamine oxidase inhibitors in treatment-resistant depressive disorders in clinical practice; a retrospective open-label study'.

[A protocol for light therapy in bipolar disorder]. / Protocol voor lichttherapie bij bipolaire stoornis.

BACKGROUND: There is no national protocol for the use of light therapy in bipolar depression.
AIM: The chronotherapy collaboration group of the Foundation for Bipolar Disorders intended to write a protocol for light therapy in bipolar depressive episodes.
METHOD: Narrative review of several systematic reviews, two clinician's guides and deliberation with the sub-commission Guidelines of the Dutch Ophthalmologic Society.
RESULTS: The following indication was established: depressive episode, with or without seasonal features, in bipolar I or II disorder, including subsyndromal (depressive) seasonal complaints. The list of relative contra-indications (pre-existent retinal illnesses, systemic illnesses with effect on the retina and use of photosensitive medication) was shortened. In this case the medical professional discusses the possibility of an ophthalmologic consultation with the patient. Use of a mood stabilizer/antimanic medication in order to prevent mania or a mixed episode is only necessary in a depressive episode in bipolar I, but not in bipolar II disorder. Standard treatment is 10.000 lux white light during 30 minutes in the morning.
CONCLUSION: There is sufficient evidence to propose light therapy in a bipolar depressive episode with or without seasonal features.

Association between exposure to anaesthesia and surgery and long-term cognitive trajectories in older adults: report from the Mayo Clinic Study of Aging.

BACKGROUND: The link between exposure to general anaesthesia and surgery (exposure) and cognitive decline in older adults is debated. We hypothesised that it is associated with cognitive decline. METHODS: We analysed the longitudinal cognitive function trajectory in a cohort of older adults. Models assessed the rate of change in cognition over time, and its association with exposure to anaesthesia and surgery. Analyses assessed whether exposure in the 20 yr before enrolment is associated with cognitive decline when compared with those unexposed, and whether post-enrolment exposure is associated with a change in cognition in those unexposed before enrolment. RESULTS: We included 1819 subjects with median (25th and 75th percentiles) follow-up of 5.1 (2.7-7.6) yr and 4 (3-6) cognitive assessments. Exposure in the previous 20 yr was associated with a greater negative slope compared with not exposed (slope: -0.077 vs -0.059; difference: -0.018; 95% confidence interval: -0.032, -0.003; P=0.015). Post-enrolment exposure in those previously unexposed was associated with a change in slope after exposure (slope: -0.100 vs -0.059 for post-exposure vs pre-exposure, respectively; difference: -0.041; 95% confidence interval: -0.074, -0.008; P=0.016). Cognitive impairment could be attributed to declines in memory and attention/executive cognitive domains. CONCLUSIONS: In older adults, exposure to general anaesthesia and surgery was associated with a subtle decline in cognitive z-scores. For an individual with no prior exposure and with exposure after enrolment, the decline in cognitive function over a 5 yr period after the exposure would be 0.2 standard deviations more than the expected decline as a result of ageing. This small cognitive decline could be meaningful for individuals with already low baseline cognition.

Characterizing risk assessments for the development of occupational exposure limits for engineered nanomaterials.

The commercialization of engineered nanomaterials (ENMs) began in the early 2000's. Since then the number of commercial products and the number of workers potentially exposed to ENMs is growing, as is the need to evaluate and manage the potential health risks. Occupational exposure limits (OELs) have been developed for some of the first generation of ENMs. These OELs have been based on risk assessments that progressed from qualitative to quantitative as nanotoxicology data became available. In this paper, that progression is characterized. It traces OEL development through the qualitative approach of general groups of ENMs based primarily on read-across with other materials to quantitative risk assessments for nanoscale particles including titanium dioxide, carbon nanotubes and nanofibers, silver nanoparticles, and cellulose nanocrystals. These represent prototypic approaches to risk assessment and OEL development for ENMs. Such substance-by-substance efforts are not practical given the insufficient data for many ENMs that are currently being used or potentially entering commerce. Consequently, categorical approaches are emerging to group and rank ENMs by hazard and potential health risk. The strengths and limitations of these approaches are described, and future derivations and research needs are discussed. Critical needs in moving forward with understanding the health effects of the numerous EMNs include more standardized and accessible quantitative data on the toxicity and physicochemical properties of ENMs.

A rainbow trout Oncorhynchus mykiss strain with higher aerobic scope in normoxia also has superior tolerance of hypoxia.

This study compared parr from three strains of rainbow trout Oncorhynchus mykiss to examine intraspecific variation in metabolic traits, hypoxia tolerance and upper thermal tolerance in this species. At the strain level, variation in absolute aerobic scope (AAS), critical oxygen level (O2crit ), incipient lethal oxygen saturation (ILOS) and critical thermal maximum (CTmax ) generally exhibited consistent differences among the strains, suggesting the possibility of functional associations among these traits. This possibility was further supported at the individual level by a positive correlation between ILOS and O2crit and a negative correlation between O2crit and AAS. These results indicate that intraspecific differences in hypoxia tolerance among strains of O. mykiss may be primarily determined by differences in the ability to maintain oxygen uptake in hypoxia and that variation in aerobic scope in normoxia probably plays a role in determining the ability of these fish to sustain metabolism aerobically as water oxygen saturation is reduced.

[The use of anticonvulsants and the levels of folate, vitamin B12 and homocysteine]. / Invloed van anti-epileptica op foliumzuur-, vitamine B12- en homocysteïnewaarden.

BACKGROUND Patients with epilepsy who use anticonvulsants frequently show low levels of folate and vitamin B12 and high levels of homocysteine. Patients with bipolar disorder use some anticonvulsants as mood stabilisers.
AIM: To determine whether some anticonvulsants lower folate and vitamin B12 and raise homocysteine levels.
METHOD: Systematic literature search to determine the relation between the anticonvulsants valproic acid, carbamazepine, lamotrigine and topiramate on the one hand and blood levels of folate, vitamin B12 and homocysteine on the other hand.
RESULTS: The vast majority of studies in adults and children showed a correlation between use of anticonvulsant carbamazepine and decrease of the folate level. Hardly any of the studies that examined the effect of valproic acid on folate levels found a correlation. There was next to no evidence of a correlation between the use of carbamazepine and a low vitamin B12 level in adults or children. In adults and children the use of valproic acid was found to correlate with a higher vitamin B12 level. Nearly all studies found an increase in homocysteine in adults and children using carbamazepine. Among the users of valproic acid, it was only children who showed a clear association with a rise in homocysteine level. The results for adults were contradictory. We were unable to make any clear statement about topiramate or lamotrigine because there have been very few publications about these anticonvulsants.
CONCLUSION: In adults and children with epilepsy use of carbamazepine is associated with a decrease of folate, valproic acid with a rise in the vitamin B12 level, and carbamazepine with an increase in homocysteine. Valproic acid showed only in children an association with the rise of the homocysteine level. Psychiatrists may find it advisable to control the levels of folate and homocysteine in adults and children who are taking carbamazepine and to measure homocysteine level in children taking valproic acid.

Adjunctive memantine in clozapine-treated refractory schizophrenia: an open-label 1-year extension study.

BACKGROUND: In a recent placebo-controlled, double-blind crossover trial (n = 52), significant beneficial effects on memory (d = 0.30) and negative symptoms (d = 0.29) were found after 12 weeks of memantine augmentation in patients with clozapine-refractory schizophrenia. In this open-label 1-year extension study we report the long-term effects and tolerability of memantine add-on therapy to clozapine. METHOD: Completers of the first trial who experienced beneficial effects during 12 weeks of memantine treatment received memantine for 1 year. Primary endpoints were memory and executive function using the Cambridge Neuropsychological Test Automated Battery, the Positive and Negative Syndrome Scale (PANSS), and the Clinical Global Impression Severity Scale (CGI-S). RESULTS: Of 31 randomized controlled trial completers who experienced beneficial effects from memantine, 24 received memantine for 1 year. The small improvement in memory found in the memantine condition in the placebo-controlled trial remained stable in the extension study. Executive function did not improve. After 26 weeks of memantine add-on therapy to clozapine, PANSS negative symptoms (r = 0.53), PANSS positive symptoms (r = 0.50) and PANSS total symptoms (r = 0.54) significantly improved. Even further significant improvement in all these measures was observed between 26 weeks and 52 weeks of memantine, with effect sizes varying from 0.39 to 0.51. CGI-S showed a non-significant moderate improvement at 26 weeks (r = 0.36) and 52 weeks (r = 0.34). Memantine was well tolerated without serious adverse effects. CONCLUSIONS: In the 1-year extension phase the favourable effect of adjunctive memantine on memory was sustained and we observed further improvement of negative, positive and overall symptoms in patients with clozapine-treated refractory schizophrenia.

Intrinsic reproductive isolating mechanisms in the maintenance of a hybrid zone between ecologically divergent subspecies.

Understanding factors involved in maintaining stable hybrid zones is important for predicting the ultimate fate of the interacting taxa, but the relative importance of mechanisms such as ecological selection and intrinsic reproductive isolation remains unclear. Most studies of reproductive isolation in hybrid zones have focused either on zones with strongly bimodal patterns in genotype or phenotype frequencies, with relatively strong isolation, or unimodal zones with relatively weak isolation, whereas less is known about more intermediate classes of hybrid zone. Here, we utilize a hybrid zone of this intermediate type occurring between northern and southern subspecies of Atlantic killifish, Fundulus heteroclitus, to identify isolating mechanisms playing a role in maintaining this type of zone. The two subspecies differ in environmental tolerance, and we found some evidence of microhabitat preference between subspecies within a small tidal creek at the centre of the hybrid zone. There was also an association between sex, mitochondrial genotype and habitat within this creek. Fertilization success did not differ between consubspecific and heterosubspecific crosses, but hatching success was significantly lower for crosses involving southern males and northern females, and crosses between southern females and northern males had altered developmental rates. Southern females and northern males showed patterns consistent with positive assortative mating. Together, these results indicate a role for a combination of factors including assortative mating and/or early hybrid inviability in the maintenance of this hybrid zone and suggest that hybrid zones with intermediate levels of reproductive isolation are likely to be maintained by multiple interacting isolating mechanisms.

[Lithium and its protective effect in Alzheimer's disease]. / Het beschermende effect van lithium bij de ziekte van Alzheimer.

BACKGROUND: Lithium is associated with adverse effects on cognitive functioning. However, there are published trials that have investigated the protective effects of lithium in cognitive decline.
AIM: To review studies that investigate the potentially protective effects of lithium on cognitive disorders.
METHOD: We studied English-language and Dutch reports on controlled, clinical trials published up to October 2016.
RESULTS: We found four relevant articles. Two studies indicated that cognitive functioning remained more stable when patients were given lithium than when they were given a placebo. One study, however, could not detect any difference between the effects of lithium and the effects of placebos. The fourth study, which examined patients' ability to tolerate lithium, could not find any difference in the cognitive functioning of patients.
CONCLUSION: The reported results indicate that the cognitive functioning of patients with pre-stage Alzheimer's disease remains more stable after patients have taken lithium than after they have taken a placebo.

[Pimavanserin: a new treatment for the Parkinson's disease psychosis]. / Pimavanserine: een nieuwe behandeling voor psychose bij de ziekte van Parkinson.

BACKGROUND: Clozapine is an effective drug for treating psychosis in Parkinson's disease (PDP) and is registered as such in the Netherlands. However, clozapine can have adverse effects, including agranulocytosis. The new drug pimavanserin was recently registered in the United States for the treatment of PDP.
AIM: To review the literature on pimavanserin and discuss the position it currently occupies in the Netherlands as a potential treatment for PDP.
METHOD: Systematic search of the literature.
RESULTS: We found reports on four randomised controlled trials (RCTs), one review and six articles about the pharmacokinetics and pharmacodynamics of pimavanserin. Pimavanserin is an effective treatment for PDP, and, like clozapine, it has very few negative effects on motor skills. However, all of the RCTs were funded by the manufacturer of pimavanserin and the trials were conducted in a very selective patient population. This means that results cannot be generalised. Long-term results are not yet available. In earlier trials clozapine was shown to have a greater and faster antipsychotic effect. Many clinicians and psychiatrists have a great deal of experience with this drug. Another important point is that no-one has yet conducted a trial comparing clozapine and pimavanserin.
CONCLUSION: Given that the current second drug of choice, namely quetiapine, has not been found to be effective for PDP, we are of the opinion that - if pimavanserin is registered in the Netherlands - pimavanserin could be used when the current drug of choice, clozapine, is not completely effective or is poorly tolerated. For patients who have cognitive impairments in addition to psychosis, we advise testing the patient's reaction to a cholinesterase inhibitor before starting the patient on a course of antipsychotics.

Memantine augmentation in clozapine-refractory schizophrenia: a randomized, double-blind, placebo-controlled crossover study.

BACKGROUND: Dysfunction of neuroplasticity due to N-methyl-d-aspartate (NMDA) receptor hypofunction may be a causal factor for memory and executive dysfunctioning in schizophrenia. Deregulation of NMDA transmission in the prefrontal cortex may also explain negative and positive symptoms. Clozapine augmentation with memantine targets altered NMDA receptor-mediated neurotransmission in schizophrenia and showed substantial beneficial effects on several symptom domains in a small proof-of-concept study. We evaluate effects of memantine add-on treatment to clozapine for memory and executive function, and negative and positive symptoms in schizophrenia. METHOD: Clozapine-treated patients with refractory schizophrenia were randomly assigned to 12 weeks of double-blind adjunctive treatment with memantine (n = 26) or placebo (n = 26). Crossover occurred after a 2-week placebo wash-out period. Primary endpoints were change from baseline to 12 weeks treatment and 14 weeks to 26 weeks treatment on memory and executive function using the Cambridge Neuropsychological Test Automated Battery (CANTAB), Positive and Negative Syndrome Scale (PANSS), and Clinical Global Impression Severity Scale (CGI-S). Side effects were assessed using the Liverpool University Neuroleptic Side-Effect Rating Scale. RESULTS: When compared with placebo, memantine improved a composite memory score comprising verbal recognition memory and paired associates learning task scores on the CANTAB (effect size = 0.30) and PANSS negative subscale score (effect size = 0.29). Side effects were mild and transient. CONCLUSIONS: In patients with clozapine-treated refractory schizophrenia, memantine addition significantly improved verbal and visual memory and negative symptoms without serious adverse effects. These results justify further investigations on long-term memantine augmentation to clozapine in treatment-resistant schizophrenia.

High educational performance is a distinctive feature of bipolar disorder: a study on cognition in bipolar disorder, schizophrenia patients, relatives and controls.

BACKGROUND: Schizophrenia is associated with lower intelligence and poor educational performance relative to the general population. This is, to a lesser degree, also found in first-degree relatives of schizophrenia patients. It is unclear whether bipolar disorder I (BD-I) patients and their relatives have similar lower intellectual and educational performance as that observed in schizophrenia. METHOD: This cross-sectional study investigated intelligence and educational performance in two outpatient samples [494 BD-I patients, 952 schizophrenia spectrum (SCZ) patients], 2231 relatives of BD-I and SCZ patients, 1104 healthy controls and 100 control siblings. Mixed-effects and regression models were used to compare groups on intelligence and educational performance. RESULTS: BD-I patients were more likely to have completed the highest level of education (odds ratio 1.88, 95% confidence interval 1.66-2.70) despite having a lower IQ compared to controls (ß = -9.09, S.E. = 1.27, p < 0.001). In contrast, SCZ patients showed both a lower IQ (ß = -15.31, S.E. = 0.86, p < 0.001) and lower educational levels compared to controls. Siblings of both patient groups had significantly lower IQ than control siblings, but did not differ on educational performance. IQ scores did not differ between BD-I parents and SCZ parents, but BD-I parents had completed higher educational levels. CONCLUSIONS: Although BD-I patients had a lower IQ than controls, they were more likely to have completed the highest level of education. This contrasts with SCZ patients, who showed both intellectual and educational deficits compared to healthy controls. Since relatives of BD-I patients did not demonstrate superior educational performance, our data suggest that high educational performance may be a distinctive feature of bipolar disorder patients.

Advancing the framework for considering the effects of climate change on worker safety and health.

In 2009, a preliminary framework for how climate change could affect worker safety and health was described. That framework was based on a literature search from 1988-2008 that supported seven categories of climate-related occupational hazards: (1) increased ambient temperature; (2) air pollution; (3) ultraviolet radiation exposure; (4) extreme weather; (5) vector-borne diseases and expanded habitats; (6) industrial transitions and emerging industries; and (7) changes in the built environment. This article reviews the published literature from 2008-2014 in each of the seven categories. Additionally, three new topics related to occupational safety and health are considered: mental health effects, economic burden, and potential worker safety and health impacts associated with the nascent field of climate intervention (geoengineering). Beyond updating the literature, this article also identifies key priorities for action to better characterize and understand how occupational safety and health may be associated with climate change events and ensure that worker health and safety issues are anticipated, recognized, evaluated, and mitigated. These key priorities include research, surveillance, risk assessment, risk management, and policy development. Strong evidence indicates that climate change will continue to present occupational safety and health hazards, and this framework may be a useful tool for preventing adverse effects to workers.

Physical activity as a determinant of fasting and 2-h post-challenge glucose: a prospective cohort analysis of the NAVIGATOR trial.

AIM: To investigate whether previous physical activity levels are associated with blood glucose levels in individuals with impaired glucose tolerance in the context of an international pharmaceutical trial. METHODS: Data were analysed from the NAVIGATOR trial, which involved 9306 individuals with impaired glucose tolerance and high cardiovascular risk from 40 different countries, recruited in the period 2002-2004. Fasting glucose, 2-h post-challenge glucose and physical activity (pedometer) were assessed annually. A longitudinal regression analysis was used to determine whether physical activity levels 2 years (t-2 ) and 1 year (t-1 ) previously were associated with levels of glucose, after adjusting for previous glucose levels and other patient characteristics. Those participants with four consecutive annual measures of glucose and two consecutive measures of physical activity were included in the analysis. RESULTS: The analysis included 3964 individuals. Change in physical activity from t-2 to t-1 and activity levels at t-2 were both associated with 2-h glucose levels after adjustment for previous glucose levels and baseline characteristics; however, the associations were weak: a 100% increase in physical activity was associated with a 0.9% reduction in 2-h glucose levels. In addition, previous physical activity only explained an additional 0.05% of the variance in 2-h glucose over the variance explained by the history of 2-h glucose alone (R(2)  = 0.3473 vs. 0.3468). There was no association with fasting glucose. CONCLUSIONS: In the context of a large international clinical trial, previous physical activity levels did not meaningfully influence glucose levels in those with a high risk of chronic disease, after taking into account participants' previous trajectory of glucose control.