Cannabis use among individuals in inpatient psychiatry: Trends in use, factors associated with use, and risk of 30-day readmission

Purpose: The Canadian Government has approved Bill C-45 to legalize and regulate the production, sale, and use of non-medical cannabis. Certain subpopulations, including those with psychiatric disorders, need to be uniquely considered during policy development and continually monitored as they may be particularly vulnerable to negative outcomes associated with cannabis use. This research was conducted to evaluate current prevalence and patterns of past 30-day cannabis use among individuals admitted to inpatient psychiatry in Ontario. Methods: This study evaluated patterns of past 30-day cannabis use among individuals admitted to inpatient psychiatry in Ontario, Canada from 2006 to 2016 (n=160322). An individual’s first admission during the study period (index admission) was used for the analysis. Prevalence rates were established, and trends were stratified by age, sex, and psychiatric diagnosis. Variables significantly associated with past 30-day use at the bivariate level were identified. Block modelling was carried out with significant variables to construct a logistic regression model that describes characteristics associated with past 30-day use. This process was repeated for 30-day readmissions. Cannabis was added to the final model to determine whether it remained significantly associated with readmissions after controlling for other variables. Factors associated with readmissions among past 30-day cannabis users and non-users were identified. Results: Past 30-day cannabis use increased from 15.4% to 25.3% from 2006 to 2016. Although more males reported past 30-day cannabis use, non-males had a greater increase in use across the study period. Persons ages 18 to 24 had the highest rates of cannabis use. However, older age categories also had increases in rates of use over time. Younger individuals with substance-related and addictive disorders, males with schizophrenia and other psychotic disorders, and those with mood disorders all had greater odds of reporting past 30-day cannabis use, while a neurocognitive diagnosis was associated with reduced odds. Greater use was found among those with shorter lengths of stay, a history of violence, experiences of traumatic life events and financial hardship, poorer medication adherence, fewer lifetime psychiatric hospitalizations, and more severe symptoms and clinical measures (positive symptoms, social withdrawal, cognitive performance, mania symptoms, and indicators of addiction). After controlling for other variables, cannabis was significantly associated with readmissions for those exhibiting positive symptoms. Variables associated with readmissions for recent users were highly related to psychosis and may be associated with more complex and less compliant patients. Conclusions: A steady increase in past 30-day cannabis use from 2006 to 2016 was found. Continual monitoring of psychiatric admissions following legalization is important to determine whether an increase in cannabis use is associated with increased admissions. Several characteristics describing past 30-day cannabis users in inpatient psychiatry mimic that of users in the general population. Additional variables associated with past 30-day cannabis use were identified for the inpatient population which can be used to follow this population. Past 30-day cannabis use was significantly associated with 30-day readmissions for those exhibiting positive symptoms. Appropriate education and care planning is crucial in order to improve clinical outcomes and reduce unnecessary readmissions

IRRIGATION DISTRICT ADOPTION OF WATER CONSERVING RATE STRUCTURES

A binary choice model was used to identify the attributes that influence irrigation district adoption of conservation rate structures. Using principles of rate design and irrigation district administration as a framework, measures of irrigation district rate structure objectives and physical and economic conditions were developed. The factors investigated characterize the constraints under which districts operate, value and cost of water, quantity of water delivered and revenue risk for districts. Rate structure adoption was predicted with over 75% accuracy. Both significant and non-significant factors are key to understanding rate choice. Districts were more likely to adopt conservation rate pricing when the cost of water to farmers was greater, higher value crops were grown and in areas with warmer and longer growing seasons. These conditions may be interpreted as reflecting the presence of greater opportunity costs in allocating water between low and higher valued uses. Conservation rate pricing was less likely to be adopted by districts where the proportion of alfalfa to total acreage was higher and with higher per acre deliveries of water. Somewhat surprisingly, annual variation in water deliveries (which should increase the risk of revenue shortfalls) and size of the district (larger districts being more sophisticated) have little bearing on the type of rate structure adopted.Environmental Economics and Policy, Land Economics/Use, Resource /Energy Economics and Policy,

EMERGING AGRICULTURAL WATER CONSERVATION PRICE INCENTIVES

Recent Bureau of Reclamation policies encourage or require irrigation districts to adopt price conservation incentives. Using unpublished survey results and new district-level information, we examine the rate structures and incentives of district water pricing. Our findings reveal that the majority of districts use fixed charges independent of the quantity of water delivered and that most conservation rate structures recently implemented are designed so that the first tier quantity allocation satisfies most crop water needs. Although other district management objectives may be satisfied, price incentives are diminished or nonexistent. The question of whether conservation is being achieved is tautological and depends on how each district defines conservation.Resource /Energy Economics and Policy,

EVALUATING THE EFFECTIVENESS OF CONSERVATION WATER-PRICING PROGRAMS: REPLY

Resource /Energy Economics and Policy,

EVALUATING THE EFFECTIVENESS OF CONSERVATION WATER-PRICING PROGRAMS

Charging farmers increasing block prices for irrigation deliveries is advocated as a means of encouraging agricultural water conservation in the West. We formulated a model of a hypothetical irrigated river basin to investigate the hyrdro-economic circumstances in which such pricing leads to water conservation. Our results indicate that increasing delivery prices may encourage irrigators to make adjustments with countervailing impacts on consumptive water use and conservation. Whether these countervailing impacts combine to conserve water or increase its consumptive use must be resolved empirically. An alternative resolution of this ambiguity is to assess water prices in terms of consumptive use.Resource /Energy Economics and Policy,

How High? Trends in Cannabis Use Prior to First Admission to Inpatient Psychiatry in Ontario, Canada, between 2007 and 2017

Objectives: To examine the trends in cannabis use within 30 days of first admission to inpatient psychiatry in Ontario, Canada, between 2007 and 2017, and the characteristics of persons reporting cannabis use. Methods: A retrospective cross-sectional analysis was conducted for first-time admissions to nonforensic inpatient psychiatric beds in Ontario, Canada, between January 1, 2007, and December 31, 2017, using data from the Ontario Mental Health Reporting System (N = 81,809). Results: Across all years, 20.1% of patients reported cannabis use within 30 days of first admission. Use increased from 16.7% in 2007 to 25.9% in 2017, and the proportion with cannabis use disorders increased from 3.8% to 6.0%. In 2017, 47.9% of patients aged 18 to 24 and 39.2% aged 25 to 34 used cannabis, representing absolute increases of 8.3% and 10.7%, respectively. Increases in cannabis use were found across almost all diagnostic groups, with the largest increases among patients with personality disorders (15% increase), schizophrenia or other psychotic disorders (14% increase), and substance use disorders (14% increase). A number of demographic and clinical factors were significantly associated with cannabis use, including interactions between schizophrenia and gender (area under the curve = 0.88). Conclusions: As medical cannabis policies in Canada have evolved, cannabis use reported prior to first admission to inpatient psychiatry has increased. The findings of this study establish a baseline for evaluating the impact of changes in cannabis-related policies in Ontario on cannabis use prior to admission to inpatient psychiatry

The Role of the Mucus Barrier in Digestion

Mucus forms a protective layer across a variety of epithelial surfaces. In the gastrointestinal (GI) tract, the barrier has to permit the uptake of nutrients, while excluding potential hazards, such as pathogenic bacteria. In this short review article, we look at recent literature on the structure, location, and properties of the mammalian intestinal secreted mucins and the mucus layer they form over a wide range of length scales. In particular, we look at the structure of the gel-forming glycoprotein MUC2, the primary intestinal secreted mucin, and the influence this has on the properties of the mucus layer. We show that, even at the level of the protein backbone, MUC2 is highly heterogeneous and that this is reflected in the networks it forms. It is evident that a combination of charge and pore size determines what can diffuse through the layer to the underlying gut epithelium. This information is important for the targeted delivery of bioactive molecules, including nutrients and pharmaceuticals, and for understanding how GI health is maintained

The host immune response to gastrointestinal nematode infection in sheep

non peer reviewedGastrointestinal nematode infection represents a major threat to the health, welfare and productivity of sheep populations worldwide. Infected lambs have a reduced ability to absorb nutrients from the gastrointestinal tract, resulting in morbidity and occasional mortality. The current chemo-dominant approach to nematode control is considered unsustainable due to the increasing incidence of anthelmintic resistance. In addition there is growing consumer demand for food products from animals not subjected to chemical treatment. Future mechanisms of nematode control must rely on alternative, sustainable strategies such as vaccination or selective breeding of resistant animals. Such strategies take advantage of the host's natural immune response to nematodes. The ability to resist gastrointestinal nematode infection is considered to be dependent on the development of a protective acquired immune response; although the precise immune mechanisms involved in initiating this process remain to be fully elucidated. In this paper current knowledge on the innate and acquired host immune response to gastrointestinal nematode infection in sheep and the development of immunity is reviewed.We gratefully acknowledge funding support for the research in our laboratories from the Teagasc Walsh Fellowship Programme, the Allan and Grace Kay Overseas Scholarship and the EC-funded FP7 Programme. We also thank the BBSRC Animal Health Research Club for funding part of this research (grant BB/l004070/1