Estimating the association between metabolic risk factors and marijuana use in U.S. adults using data from the continuous National Health and Nutrition Examination Survey

Overactivation of the Endocannabinoid System in Adolescence Disrupts Adult Adipose Organ Function in Mice

Cannabis use stimulates calorie intake, but epidemiological studies show that people who regularly use it are leaner than those who don't. Two explanations have been proposed for this paradoxical finding. One posits that Δ9-tetrahydrocannabinol (THC) in cannabis desensitizes adipose CB1 cannabinoid receptors, stopping their stimulating effects on lipogenesis and adipogenesis. Another explanation is that THC exposure in adolescence, when habitual cannabis use typically starts, produces lasting changes in the developing adipose organ, which impacts adult systemic energy use. Here, we consider these possibilities in the light of a study which showed that daily THC administration in adolescent mice produces an adult metabolic phenotype characterized by reduced fat mass, partial resistance to obesity and dyslipidemia, and impaired thermogenesis and lipolysis. The phenotype, whose development requires activation of CB1 receptors in differentiated adipocytes, is associated with overexpression of myocyte proteins in the adipose organ with unchanged CB1 expression. We propose that adolescent exposure to THC causes lasting adipocyte dysfunction and the consequent emergence of a metabolic state that only superficially resembles healthy leanness. A corollary of this hypothesis, which should be addressed in future studies, is that CB1 receptors and their endocannabinoid ligands may contribute to the maintenance of adipocyte differentiation during adolescence.

Cannabis use disorder and adverse cardiovascular outcomes: A population-based retrospective cohort analysis of adults from Alberta, Canada

AIM

To measure the association between cannabis use disorder (CUD) and adverse cardiovascular disease (CVD) outcomes.

DESIGN AND SETTING

We conducted a matched, population-based retrospective cohort study involving five linked administrative health databases from Alberta, Canada.

PARTICIPANTS

We identified participants with CUD diagnosis codes and matched them to participants without CUD codes by gender, year of birth and time of presentation to the health system. We included 29 764 pairs (n = 59 528 individuals in total).

MEASUREMENTS

CVD events were defined by at least one incident diagnostic code within the study period (1 January 2012-31 December 2019). Covariates included comorbidity, socio-economic status, prescription medication use and health service use. Using mortality-censored Poisson regression models, we computed survival analyses for time to incident CVD stratified by CUD status. In addition, we calculated crude and stratified risk ratios (RRs) across various covariates using the Mantel-Haenszel technique.

FINDINGS

The overall prevalence of documented CUD was 0.8%. Approximately 2.4% and 1.5% of participants in the CUD and unexposed groups experienced an incident adverse CVD event (RR = 1.57; 95% confidence interval = 1.40-1.77). CUD was significantly associated with reduced time to incident CVD event. Individuals who appeared to have greater RRs for incident CVD were those without mental health comorbidity, who had not used health-care services in the previous 6 months, who were not on prescription medications and who did not have comorbid conditions.

CONCLUSIONS

Canadian adults with cannabis use disorder appear to have an approximately 60% higher risk of experiencing incident adverse cardiovascular disease events than those without cannabis use disorder.

Adolescent exposure to low-dose THC disrupts energy balance and adipose organ homeostasis in adulthood

One of cannabis' most iconic effects is the stimulation of hedonic high-calorie eating-the "munchies"-yet habitual cannabis users are, on average, leaner than non-users. We asked whether this phenotype might result from lasting changes in energy balance established during adolescence, when use of the drug often begins. We found that daily low-dose administration of cannabis' intoxicating constituent, Δ9-tetrahydrocannabinol (THC), to adolescent male mice causes an adult metabolic phenotype characterized by reduced fat mass, increased lean mass and utilization of fat as fuel, partial resistance to diet-induced obesity and dyslipidemia, enhanced thermogenesis, and impaired cold- and β-adrenergic receptor-stimulated lipolysis. Further analyses revealed that this phenotype is associated with molecular anomalies in the adipose organ, including ectopic overexpression of muscle-associated proteins and heightened anabolic processing. Thus, adolescent exposure to THC may promote an enduring "pseudo-lean" state that superficially resembles healthy leanness but might in fact be rooted in adipose organ dysfunction.

Digital Inclusion, Cultural Capital, and Health Status of Urban and Rural Residents: An Empirical Study Based on 2017 CGSS Database

China is committed to using digital technology to drive urban-rural integration in health care. This study aims to explore the effect of digital inclusion on health status with the mediating role of cultural capital and the digital health disparities between urban and rural residents in China. Using data from the 2017 Chinese General Social Survey (CGSS), the present study adopted an ordinary least squares (OLS) robust standard error regression model to investigate the impact of digital inclusion on health status. In addition, causal step regression (CSR) and bootstrapping methods were combined to test the mediating effect of cultural capital. The results showed that, first, digital inclusion was related to positive and significant effects on resident health status. Second, cultural capital played a mediating role in the relationship between digital inclusion and health status. Third, urban residents gained more health benefits from digital inclusion than rural residents. Additionally, common method variance (CMV) tests, endogenous tests, and a propensity score matching (PSM) analysis showed that the above conclusions remained robust. The government should therefore focus not only on promoting the population's health by utilizing digital inclusion but also on accelerating digital health equity between urban and rural areas by developing such strategies as a digital infrastructure expansion schedule and digital literacy education and training programs.

The effects of cannabis and cannabinoids on the endocrine system

With the increase in cannabis use due to policy changes and areas of decriminalization, it is important to recognize the potential impact of these substances on endocrine processes. Cannabinoids have many effects by activating the endocannabinoid system. This system plays a role in the normal functioning of nearly every organ and consists of the body's natural endocannabinoids, the cannabinoid receptors, and the enzymes and processes that regulate endocannabinoids. Exogenous cannabinoids such as Δ9-tetrahydrocannabinol (THC) are known to act through cannabinoid type 1 and 2 receptors, and have been shown to mimic endocannabinoid signaling and affect receptor expression. This review summarizes the known impacts of cannabis on thyroid, adrenal, and gonadal function in addition to glucose control, lipids, and bone metabolism, including: reduced female fertility, increased risk of adverse pregnancy outcomes, reduced sperm counts and function, lower thyroid hormone levels with acute use, blunting of stress response with chronic use, increased risk of prediabetes but lower risk of diabetes, suggested improvement of high density lipoproteins and triglycerides, and modest increase in fracture risk. The known properties of endocannabinoids, animal data, population data, and the possible benefits and concerns of cannabinoid use on hormonal function are discussed. The interconnectivity of the endocrine and endocannabinoid systems suggests opportunities for future therapeutic modalities which are an area of active investigation.

Cannabis use does not impact on type 2 diabetes: A two-sample Mendelian randomization study

Cannabis has effects on the insulin/glucose metabolism. As the use of cannabis and the prevalence of type 2 diabetes increase worldwide, it is important to examine the effect of cannabis on the risk of diabetes. We conducted a Mendelian randomization (MR) study by using 19 single-nucleotide polymorphisms (SNPs) as instrumental variables for lifetime cannabis use and 14 SNPs to instrument cannabis use disorder and linking these to type 2 diabetes risk using genome-wide association study data (lifetime cannabis use [N = 184,765]; cannabis use disorder [2387 cases/48,985 controls], type 2 diabetes [74,124 cases/824,006 controls]). The MR analysis suggested no effect of lifetime cannabis use (inverse-variance weighted odds ratio [95% confidence interval] = 1.00 [0.93-1.09], P value = 0.935) and cannabis use disorder (OR = 1.03 [0.99-1.08]) on type 2 diabetes. Sensitivity analysis to assess potential pleiotropy led to no substantive change in the estimates. This study adds to the evidence base that cannabis use does not play a causal role in type 2 diabetes.

Association of Opioid Use With Cardiometabolic Disease Risk Factors: Evidence From the 2009-2018 National Health and Nutrition Examination Survey

Objective

To investigate the association between opioid drug use and cardiometabolic risk factors in an adult sample data acquired from the National Health and Nutrition Examination Survey (NHANES).

Methods

A retrospective cross-sectional analysis was performed using the data from the NHANES for the period 2009-2018 provided by the Centers for Disease Control and Prevention (CDC), amounting to a total of N = 10,032 eligible participants. The data were analyzed to study the relationship between opioid drug use (dividing into four dichotomy groups: drug use (DU) group, illicit drug use (IDU) group, repeated drug use (RDU) group, and current drug use (CDU) group) and cardiometabolic disease risk factors (CDRF) (i.e., hypertension, abnormal triglyceride levels, low-level of high-density lipoproteins (HDLs), high waist circumference, insulin resistance, serum cotinine levels, higher C-reactive protein, hypercholesterolemia, and increased BMI). The statistical correlation was evaluated using the chi-square analysis, and a p-value of less than 0.05 was considered statistically significant. Alcohol use, age, race, ethnicity, education level, and poverty to income ratio (PIR) were analyzed as covariates. 

Results

Overall, our analysis found that males were more likely than females (p ≤ 0.001) to have ever reported using drugs at least once in their lifetime. In fact, males were more likely than females to report ever using cocaine (p = 0.01), heroin (p = 0.01), and marijuana (p = 0.01). Additionally, males were significantly more likely than females to disclose the current use of illicit drugs (p = 0.002), and also tend to have consumed more with at least 12 alcoholic beverages per year (p < 0.001). Overall, we found no association between substance use and having a cluster of three or more CDRF variables for both males and females.

Conclusion

Study results highlight the prevalence of gender differences in DU and its reporting. With the rising popularity of illicit drugs, clinicians must be aware of its association with CDRF.

Targeting the Endocannabinoid CB1 Receptor to Treat Body Weight Disorders: A Preclinical and Clinical Review of the Therapeutic Potential of Past and Present CB1 Drugs

Obesity rates are increasing worldwide and there is a need for novel therapeutic treatment options. The endocannabinoid system has been linked to homeostatic processes, including metabolism, food intake, and the regulation of body weight. Rimonabant, an inverse agonist for the cannabinoid CB1 receptor, was effective at producing weight loss in obese subjects. However, due to adverse psychiatric side effects, rimonabant was removed from the market. More recently, we reported an inverse relationship between cannabis use and BMI, which has now been duplicated by several groups. As those results may appear contradictory, we review here preclinical and clinical studies that have studied the impact on body weight of various cannabinoid CB1 drugs. Notably, we will review the impact of CB1 inverse agonists, agonists, partial agonists, and neutral antagonists. Those findings clearly point out the cannabinoid CB1 as a potential effective target for the treatment of obesity. Recent preclinical studies suggest that ligands targeting the CB1 may retain the therapeutic potential of rimonabant without the negative side effect profile. Such approaches should be tested in clinical trials for validation.

Associations Between Cannabis Use and Cardiometabolic Risk Factors: A Longitudinal Study of Men

OBJECTIVE

This study tested longitudinal associations between cannabis use and cardiometabolic risk factors that underlie the development of cardiovascular diseases.

METHODS

Participants were men from the youngest cohort of the Pittsburgh Youth Study who were followed prospectively from approximately age 7 to 32 years (N = 253). Frequency of cannabis use was assessed yearly from approximately ages 12 to 20 years and again at approximately ages 26, 29, and 32 years. The following cardiometabolic risk factors were assessed during a laboratory visit at approximately age 32 years: body mass index (BMI), waist-hip ratio, high- and low-density lipoprotein cholesterol, triglycerides, fasting glucose, insulin resistance, blood pressure, interleukin 6, and C-reactive protein.

RESULTS

Greater cannabis exposure was associated with relatively lower BMI (β = -0.31, p < .001), smaller waist-hip ratio (β = -0.23, p = .002), better high- (β = 0.14, p = .036) and low-density lipoprotein cholesterol (β = -0.15, p = .026), lower triglycerides (β = -0.17, p = .009), lower fasting glucose (β = -0.15, p < .001) and insulin resistance (β = -0.21, p = .003), lower systolic (β = -0.22, p < .001) and diastolic blood pressure (β = -0.15, p = .028), and fewer metabolic syndrome criteria (β = -0.27, p < .001). With exception of BMI, cannabis users' mean levels on cardiometabolic risk factors were generally below clinical cutoffs for high risk. Most associations between cannabis use and cardiometabolic risk factors remained after adjusting for tobacco use, childhood socioeconomic status, and childhood health. However, after adjusting for adult BMI, these associations were no longer apparent, and mediation tests suggested that cannabis users' relatively lower BMI might explain their lower levels of risk on other cardiometabolic risk factors.

CONCLUSIONS

Cannabis use is associated with lower BMI, and lower BMI is related to lower levels of risk on other cardiometabolic risk factors.

History of Marijuana Use Does Not Affect Outcomes on the Liver Transplant Waitlist

BACKGROUND

Data are limited on marijuana use and its impact on liver transplant (LT) waitlist outcomes. We aimed to assess the risk of waitlist mortality/delisting and likelihood of LT among prior marijuana users and to determine the prevalence and factors associated with marijuana use.

METHODS

Retrospective cohort of adults evaluated for LT over 2 years at a large LT center. Marijuana use was defined by self-report in psychosocial assessment and/or positive urine toxicology. Ongoing marijuana use was not permitted for LT listing during study period.

RESULTS

Eight hundred eighty-four adults were evaluated, and 585 (66%) were listed for LT (median follow-up, 1.4 years; interquartile range, 0.5-2.0). Prevalence of marijuana use was 48%, with 7% being recent users and 41% prior users. Marijuana use had statistically significant association with alcoholic cirrhosis (incidence rate ratio [IRR], 1.9) and hepatitis C (IRR, 2.1) versus hepatitis B, tobacco use (prior IRR, 1.4; recent IRR, 1.3 vs never), alcohol use (never IRR 0.1; heavy use/abuse IRR 1.2 vs social), and illicit drug use (prior IRR, 2.3; recent, 1.9 vs never). In adjusted competing risk regression, marijuana use was not associated with the probability of LT (prior hazard ratio [HR], 0.9; recent HR, 0.9 vs never) or waitlist mortality/delisting (prior HR, 1.0; recent HR, 1.0 vs never). However, recent illicit drug use was associated with higher risk of death or delisting (HR, 1.8; P = 0.004 vs never).

CONCLUSIONS

Unlike illicit drug use, marijuana use was not associated with worse outcomes on the LT waitlist. Prospective studies are needed to assess ongoing marijuana use on the LT waitlist and post-LT outcomes.

Sex differences in the cardiometabolic health of cannabis users with a psychotic illness

BACKGROUND

Growing evidence shows cannabis use is associated with lower rates of metabolic dysregulation. Despite cannabis impacting each sex differently, few studies have examined the metabolic profile of male and female cannabis users separately. Our aim was to investigate sex differences in the impact of cannabis use on metabolic syndrome in adults with psychotic illness.

METHOD

Data from 1078 men and 735 women interviewed in the second Australian national survey of psychosis were analyzed using multiple logistic regression to model separately, for each sex, the influence of no, occasional and frequent past-year cannabis use on metabolic syndrome, adjusting for potential covariates including antipsychotic medication, smoking, and physical activity.

RESULTS

The proportion of women and men with metabolic syndrome was 58.1% and 57.6% respectively. Unadjusted analyses showed frequent cannabis use was associated with significantly lower odds of metabolic syndrome for both sexes. In adjusted analyses, the association between metabolic syndrome and frequent cannabis use remained significant for men (AOR = 0.49, 95% CI = 0.31-0.78), but not for women (AOR = 0.68, 95% CI = 0.37-1.24). Frequent cannabis use was associated with lower odds of abdominal obesity, hypertension and elevated triglyceride levels in men only.

CONCLUSIONS

The differences we found suggest cannabinoid regulation of energy balance may be sex-dependent and highlight the importance of examining cannabis use in men and women separately. At the same time, the negative association between cannabis and psychosis onset and relapse should not be dismissed.

Theoretical Explanation for Reduced Body Mass Index and Obesity Rates in Cannabis Users

Introduction: Obesity is treatment-resistant, and is linked with a number of serious, chronic diseases. Adult obesity rates in the United States have tripled since the early 1960s. Recent reviews show that an increased ratio of omega-6 to omega-3 fatty acids contributes to obesity rates by increasing levels of the endocannabinoid signals AEA and 2-AG, overstimulating CB₁R and leading to increased caloric intake, reduced metabolic rates, and weight gain. Cannabis, or THC, also stimulates CB₁R and increases caloric intake during acute exposures. Goals: To establish the relationship between Cannabis use and body mass index, and to provide a theoretical explanation for this relationship. Results: The present meta-analysis reveals significantly reduced body mass index and rates of obesity in Cannabis users, in conjunction with increased caloric intake. Theoretical explanation: We provide for the first time a causative explanation for this paradox, in which rapid and long-lasting downregulation of CB₁R following acute Cannabis consumption reduces energy storage and increases metabolic rates, thus reversing the impact on body mass index of elevated dietary omega-6/omega-3 ratios.

Effects of cannabis use on body mass, fasting glucose and lipids during the first 12 months of treatment in schizophrenia spectrum disorders

While acute cannabis use stimulates appetite, general population studies suggest that chronic use is associated with reduced risk of obesity and other cardiometabolic risk factors. In this study we investigated changes in body mass index (BMI), fasting blood glucose and lipids, and rates of metabolic syndrome risk factors in cannabis users vs. non-users in 109 minimally treated patients with first-episode schizophrenia, schizophreniform or schizo-affective disorder who were treated according to a standardized treatment regime with depot antipsychotic medication over 12 months. Participants underwent repeated urine toxicology tests for cannabis and those testing positive at any time during the study (n = 40), were compared with those who tested negative at all time points (n = 69). There was a significant group*time interaction effect (p = 0.002) with the cannabis negative group showing a greater increase in BMI than the cannabis positive group, after adjusting for age, sex, methamphetamine use and modal dose of antipsychotic. There were no group*time interaction effects for fasting blood glucose or lipids. Post hoc tests indicated significant increases in fasting blood glucose and triglycerides and a decrease in high-density lipoprotein cholesterol for the cannabis negative group, with no significant changes in the cannabis positive group. Rates of metabolic syndrome did not differ significantly between groups, although more cannabis negative patients had elevated waist-circumference at endpoint (p = 0.003). It may be that chronic cannabis use directly suppresses appetite, thereby preventing weight gain in users. However, other indirect effects such as dietary neglect and smoking may be contributory and could explain our findings.

Associations Between Marijuana Use and Cardiovascular Risk Factors and Outcomes: A Systematic Review

BACKGROUND

Marijuana use is increasing in the United States, and its effect on cardiovascular health is unknown.

PURPOSE

To review harms and benefits of marijuana use in relation to cardiovascular risk factors and clinical outcomes.

DATA SOURCES

PubMed, MEDLINE, EMBASE, PsycINFO, and the Cochrane Library between 1 January 1975 and 30 September 2017.

STUDY SELECTION

Observational studies that were published in English, enrolled adults using any form of marijuana, and reported on vascular risk factors (hyperglycemia, diabetes, dyslipidemia, and obesity) or on outcomes (stroke, myocardial infarction, cardiovascular mortality, and all-cause mortality in cardiovascular cohorts).

DATA EXTRACTION

Study characteristics and quality were assessed by 4 reviewers independently; strength of evidence for each outcome was graded by consensus.

DATA SYNTHESIS

13 and 11 studies examined associations between marijuana use and cardiovascular risk factors and clinical outcomes, respectively. Although 6 studies suggested a metabolic benefit from marijuana use, they were based on cross-sectional designs and were not supported by prospective studies. Evidence examining the effect of marijuana on diabetes, dyslipidemia, acute myocardial infarction, stroke, or cardiovascular and all-cause mortality was insufficient. Although the current literature includes several long-term prospective studies, they are limited by recall bias, inadequate exposure assessment, minimal marijuana exposure, and a predominance of low-risk cohorts.

LIMITATION

Poor- or moderate-quality data, inadequate assessment of marijuana exposure and minimal exposure in the populations studied, and variation in study design.

CONCLUSION

Evidence examining the effect of marijuana on cardiovascular risk factors and outcomes, including stroke and myocardial infarction, is insufficient.

PRIMARY FUNDING SOURCE

National Heart, Lung, and Blood Institute. (PROSPERO: CRD42016051297).

Association Between Use of Cannabis in Adolescence and Weight Change into Midlife

Cannabis use has been found to stimulate appetite and potentially promote weight gain via activation of the endocannabinoid system. Despite the fact that the onset of cannabis use is typically during adolescence, the association between adolescence cannabis use and long-term change in body weight is generally unknown. This study aims to examine the association between adolescence cannabis use and weight change to midlife, while accounting for the use of other substances. The study applied 20 to 22 years of follow-up data on 712 Danish adolescents aged between 15 and 19 years at baseline. Self-reported height and weight, cannabis, cigarette and alcohol use, socioeconomic status (SES) and physical activity levels were assessed in baseline surveys conducted in 1983 and 1985. The follow-up survey was conducted in 2005. In total 19.1% (n = 136) of adolescents reported having used/using cannabis. Weight gain between adolescence and midlife was not related to cannabis exposure during adolescence in either crude or adjusted models, and associations were not modified by baseline alcohol intake or smoking. However, cannabis use was significantly associated with cigarette smoking (p<0.001) and alcohol intake (p<0.001) and inversely associated with physical activity levels (p = 0.04). In conclusion, this study does not provide evidence of an association between adolescence cannabis use and weight change from adolescence to midlife.

A cross-sectional analysis of the association between marijuana and cigarette smoking with metabolic syndrome among adults in the United States

AIM

To assess the relationship between marijuana use, cigarette smoking and metabolic syndrome among adults in the United States who reported they use marijuana or cigarettes in comparison to non-marijuana and non-cigarette users.

METHOD

We conducted multiple logistic regression analyses using data from the 2011-2012 United States National Health and Nutrition Examination Survey to estimate relationships between cardio-metabolic risk factors and increasing years of smoking cigarette or marijuana use. Statistical adjustments were made for both demographic and endogenous factors related to recreational substance use.

RESULTS

Each year increase in marijuana use was significantly associated with increased odds of metabolic syndrome (OR=1.05; 95% CI: 1.01, 1.09), and hypertension (OR=1.04; 95% CI: 1.01, 1.07) adjusting for both demographic and endogenous factors related to recreational substance use. Each year increase in cigarette smoking was significantly associated with increased odds of hypertension (OR=1.03; 95% CI: 1.00, 1.06) and hyperglycemia (OR=1.03; 95% CI: 1.01, 1.05) after adjusting for confounders.

CONCLUSION

The results of this investigation suggest that increased years of marijuana or cigarette use are important factors in metabolic health; and consequently calls for the need to consider the potential negative effects of marijuana or cigarette for metabolic syndrome and its associated cardio-metabolic risk components.

Metabolic Syndrome Among Marijuana Users in the United States: An Analysis of National Health and Nutrition Examination Survey Data

BACKGROUND

Research on the health effects of marijuana use in light of its increased medical use and the current obesity epidemic is needed. Our objective was to explore the relationship between marijuana use and metabolic syndrome across stages of adulthood.

METHODS

An analysis of 20- to 59-year-olds (n = 8478) who completed the 2005-2010 National Health and Nutrition Examination Surveys was conducted. Marijuana use was categorized as: never used, past use (used previously but not within the last 30 days), and current use (≥1 day in the last 30 days). Metabolic syndrome was defined as ≥3 of the following: elevated fasting glucose, high triglycerides, low high-density-lipoprotein cholesterol, elevated systolic/diastolic blood pressure, and increased waist circumference. An age-stratified analysis was conducted to examine the relationship between marijuana use and metabolic syndrome among emerging adults (20-30 years), adults (31-44 years), and middle-aged adults (45-59 years).

RESULTS

Fourteen percent (13.8%) of current marijuana users and 17.5% of past marijuana users presented with metabolic syndrome, compared with 19.5% of never users (P = .0003 and P = .03, respectively). Current marijuana users had lower odds of presenting with metabolic syndrome than never users (adjusted odds ratio [AOR] 0.69; 95% confidence interval [CI], 0.47-1.00; P = .05). Among emerging adults, current marijuana users were 54% less likely than never users to present with metabolic syndrome. Current (AOR 0.49; 95% CI, 0.25-0.97) and past (AOR 0.61; 95% CI, 0.40-0.91) middle-aged adult marijuana users were less likely to have metabolic syndrome than never users.

CONCLUSIONS

Current marijuana use is associated with lower odds of metabolic syndrome across emerging and middle-aged US adults. Future studies should examine the biological pathways of this relationship.