Biomarkers of Recent Cannabis Use in Blood, Oral Fluid and Breath

2021 ◽  
Author(s):  
J A Hubbard ◽  
M A Hoffman ◽  
S E Ellis ◽  
P M Sobolesky ◽  
B E Smith ◽  
...  
Keyword(s):  
Randomized Trial ◽  
Oral Fluid ◽  
Behavioral Assessment ◽  
Driving Under The Influence ◽  
Time Points ◽  
Behavioral Observations ◽  
Ad Libitum ◽  
Per Se ◽  
Alternative Routes ◽  
Limited Usefulness

Abstract Proving driving under the influence of cannabis (DUIC) is difficult. Establishing a biomarker of recent use to supplement behavioral observations may be a useful alternative strategy. We determined whether cannabinoid concentrations in blood, oral fluid (OF), or breath could identify use within 3h, likely the period of greatest impairment. In a randomized trial, 191 frequent (≥4/week) and occasional (<4/week) cannabis users smoked one cannabis (placebo [0.02%], 5.9% or 13.4% THC) cigarette ad libitum. Blood, OF and breath samples were collected prior to and up to 6h after smoking. Samples were analyzed for 10 cannabinoids in OF, 8 in blood, and THC in breath. Frequent users had more residual THC in blood and were categorized as “recently used” prior to smoking; this did not occur in OF. Per se limits ranging from undetectable to 5 ng/mL THC in blood offered limited usefulness as biomarkers of recent use. Cannabinol (CBN, cutoff=1 ng/mL) in blood offered 100% specificity but only 31.4% sensitivity, resulting in 100% PPV and 94.0% NPV at 4.3% prevalence; but CBN may vary by cannabis chemovar. A 10 ng/mL THC cutoff in OF exhibited the overall highest performance to detect use within 3h (99.7% specificity, 82.4% sensitivity, 92.5% PPV, 99.2% NPV) but was still detectable in 23.2% of participants ~4.4h post smoking limiting specificity at later time points. OF THC may be a helpful indicator of recent cannabis intake, but this does not equate to impairment. Behavioral assessment of impairment is still required to determine DUIC. This study only involved cannabis inhalation and additional research evaluating alternative routes of ingestion (i.e., oral) is needed.

Blood and Oral Fluid Cannabinoid Profiles of Frequent and Occasional Cannabis Smokers

2021 ◽  
Author(s):  
Melissa A Hoffman ◽  
Jacqueline A Hubbard ◽  
Philip M Sobolesky ◽  
Breland E Smith ◽  
Raymond T Suhandynata ◽  
...  
Keyword(s):  
Oral Fluid ◽  
Safety Concern ◽  
Biological Fluid ◽  
Driving Under The Influence ◽  
Sample Collection ◽  
Detection Rates ◽  
Specimen Collection ◽  
Final Sample ◽  
Cannabis Consumption ◽  
Per Se

Abstract Increased prevalence of cannabis consumption and impaired driving are a growing public safety concern. Some states adopted per se driving laws, making it illegal to drive with more than a specified ∆9-tetrahydrocannabinol (THC) blood concentration of THC in a biological fluid (typically blood). Blood THC concentrations decrease significantly (~90%) with delays in specimen collection, suggesting use of alternative matrices, such as oral fluid (OF). We characterized 10 cannabinoids’ concentrations, including THC metabolites, in blood and OF from 191 frequent and occasional users by LC–MS-MS for up to 6 h after ad libitum smoking. Subjects self-titrated when smoking placebo, 5.9 or 13.4% THC cannabis. Higher maximum blood THC concentrations (Cmax) were observed in individuals who received the 5.9% THC versus the 13.4% THC plant material. In blood, the Cmax of multiple analytes, including THC and its metabolites, were increased in frequent compared to occasional users, whereas there were no significant differences in OF Cmax. Blood THC remained detectable (≥5 ng/mL) at the final sample collection for 14% of individuals who smoked either the 5.9% or 13.4% THC cigarette, whereas 54% had detectable THC in OF when applying the same cutoff. Occasional and frequent cannabis users’ profiles were compared, THC was detectable for significantly longer in blood and OF from frequent users. Detection rates between frequent and occasional users at multiple per se cutoffs showed larger differences in blood versus OF. Understanding cannabinoid profiles of frequent and occasional users and the subsequent impact on detectability with current drug per se driving limits is important to support forensic interpretations and the development of scientifically supported driving under the influence of cannabis laws.

scholarly journals Adherence to Ketogenic and Mediterranean Study Diets in a Crossover Trial: The Keto–Med Randomized Trial

Nutrients ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 967
Author(s):  
Matthew J. Landry ◽  
Anthony Crimarco ◽  
Dalia Perelman ◽  
Lindsay R. Durand ◽  
Christina Petlura ◽  
...  
Keyword(s):  
Randomized Trial ◽  
Randomized Clinical Trials ◽  
Secondary Analysis ◽  
Critical Factor ◽  
Detailed Examination ◽  
Diet Patterns ◽  
Time Points ◽  
Study Results ◽  
Wide Range ◽  
Diet Pattern

Adherence is a critical factor to consider when interpreting study results from randomized clinical trials (RCTs) comparing one diet to another, but it is frequently not reported by researchers. The purpose of this secondary analysis of the Keto–Med randomized trial was to provide a detailed examination and comparison of the adherence to the two study diets (Well Formulated Ketogenic Diet (WFKD) and Mediterranean Plus (Med-Plus)) under the two conditions: all food being provided (delivered) and all food being obtained by individual participants (self-provided). Diet was assessed at six time points including baseline (x1), week 4 of each phase when participants were receiving food deliveries (x2), week 12 of each phase when participants were preparing and providing food on their own (x2), and 12 weeks after participants completed both diet phases and were free to choose their own diet pattern (x1). The adherence scores for WFKD and Med-Plus were developed specifically for this study. Average adherence to the two diet patterns was very similar during both on-study time points of the intervention. Throughout the study, a wide range of adherence was observed among participants—for both diet types and during both the delivery phase and self-provided phase. Insight from this assessment of adherence may aid other researchers when answering the important question of how to improve behavioral adherence during dietary trials. This study is registered at clinicaltrials.gov NCT03810378.

Protocol versus ad libitum feeds after laparoscopic pyloromyotomy: A prospective randomized trial

2014 ◽  
Vol 49 (1) ◽  
pp. 129-132 ◽  
Author(s):  
Obinna O. Adibe ◽  
Corey W. Iqbal ◽  
Susan W. Sharp ◽  
David Juang ◽  
Charles L. Snyder ◽  
...  
Keyword(s):  
Randomized Trial ◽  
Prospective Randomized Trial ◽  
Ad Libitum ◽  
Laparoscopic Pyloromyotomy

Food Drive and Satiety in Yellow Mice

1957 ◽  
Vol 189 (1) ◽  
pp. 36-38 ◽  
Author(s):  
Guy Hollifield ◽  
William Parson
Keyword(s):  
Yellow Gene ◽  
Running Activity ◽  
Fasting And Refeeding ◽  
Ad Libitum ◽  
Per Se ◽  
Relationship Of ◽  
The Relationship ◽  
Ad Libitum Feeding ◽  
Reduced Activity

Spontaneous running activity during ad libitum feeding, fasting and refeeding was studied in inbred yellow mice. These studies suggest that the yellow gene per se is not associated with reduced activity and that inbred yellow mice have intact hypothalamic feeding centers. The relationship of these findings to obesity in yellow mice is discussed.

scholarly journals Comparing Telephone Counseling With Reminding to Promote On-Time Repeated Mammography: A Randomized Trial in a Cohort With 4 Years Follow-Up

2019 ◽  
Vol 47 (1) ◽  
pp. 37-46
Author(s):  
Mary E. Costanza ◽  
Roger Luckmann ◽  
Christine Frisard ◽  
Mary Jo White ◽  
Caroline Cranos
Keyword(s):  
Confidence Interval ◽  
Randomized Trial ◽  
Odds Ratio ◽  
Multivariable Analysis ◽  
Telephone Counseling ◽  
Long Term Effects ◽  
Time Points ◽  
Reminder Call ◽  
Screening Mammograms

Background. Long-term continuous adherence to biennial screening mammograms as guidelines recommend remains low. Limited evidence suggests that reminder calls may increase short-term adherence as much as telephone counseling, but research is needed comparing the long-term effects of these two approaches. Purpose. To compare the impacts of two telephone outreach interventions and mailed reminders on 4-year continuous mammography adherence. Method. A cohort of 3,215 women, age 50 to 81 years, was selected from 30,160 women from a 4-year randomized trial of three interventions to promote biennial mammography: reminder letter only (LO), letter plus reminder call (RC), and two letters plus educational material and a counseling call (CC). Women selected remained eligible for the trial all 4 years and received annual interventions as needed. The proportion with a mammogram in the last 24 months was determined at baseline and four annual time points. Results. Continuous adherence at all four time points was higher in the RC (78.8%) and CC arms (78.8%) than in the LO arm (75.1%; p < .001). Multivariable analysis confirmed this finding: CC (odds ratio = 1.27; 95% confidence interval = [1.01, 1.61]) and RC (odds ratio = 1.23; 95% confidence interval = [0.98, 1.56]). Only 27.8% of women eligible for an initial counseling call actually received counseling. Conclusions. Compared with letters alone, outreach calls can modestly increase continuous mammography adherence among insured women with consistent primary care. Telephone counseling was no more effective than a reminder call, possibly due to limited acceptance of counseling calls by women who may find them unwelcome or unnecessary.

Are Scottish Blackface ewes more resistant to nematode parasite infection than Greyface ewes?

2009 ◽  
Vol 2009 ◽  
pp. 28-28
Author(s):  
A Kidane ◽  
J G M Houdijk ◽  
B J Tolkamp ◽  
S Athanasiadou ◽  
I Kyriazakis
Keyword(s):  
Genetic Resistance ◽  
Gastrointestinal Nematode ◽  
Parasite Infection ◽  
Nematode Parasite ◽  
Nutrient Demand ◽  
Nematode Parasites ◽  
Breed Differences ◽  
Lower Extent ◽  
Ad Libitum ◽  
Per Se

The extent of periparturient relaxation of immunity (PPRI) to gastrointestinal nematode parasites is sensitive to metabolisable protein (MP) scarcity but also varies between breeds of sheep (Houdijk, 2008). For example, under ad libitum feeding, Scottish Blackface ewes had a lower extent of PPRI than Greyface ewes (Zaralis et al., 2008). Such between-breed variation in PPRI may not necessarily be associated with genetic resistance per se but could arise from a higher nutrient demand of the more productive Greyface ewes (Houdijk, 2008). This experiment was designed to test the hypothesis that if the extent of PPRI has only a nutritional basis, then the sensitivity of PPRI to MP scarcity will not differ between the breeds when MP feeding is adjusted for between-breed differences in MP demand.

scholarly journals Randomized trial on protein vs carbohydrate in ad libitum fat reduced diet for the treatment of obesity

1999 ◽  
Vol 23 (5) ◽  
pp. 528-536 ◽  
Author(s):  
AR Skov ◽  
S Toubro ◽  
B Rønn ◽  
L Holm ◽  
A Astrup
Keyword(s):  
Randomized Trial ◽  
Ad Libitum ◽  
Treatment Of Obesity

scholarly journals Relationship Between Oral Fluid and Blood Concentrations of Drugs of Abuse in Drivers Suspected of Driving Under the Influence of Drugs

2009 ◽  
Vol 31 (4) ◽  
pp. 511-519 ◽  
Author(s):  
Sarah M R Wille ◽  
Elke Raes ◽  
Pirjo Lillsunde ◽  
Teemu Gunnar ◽  
Marleen Laloup ◽  
...  
Keyword(s):  
Oral Fluid ◽  
Drugs Of Abuse ◽  
Driving Under The Influence ◽  
Blood Concentrations
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