Taylor Michelle, Lees Rosie, Henderson Graeme, Lingford-Hughes Anne, Macleod John, Sullivan John, Hickman Matthew
MRC Integrative Epidemiology Unit at the University of Bristol, Bristol, UK.
School of Social and Community Medicine, University of Bristol, Bristol, UK.
Drug Alcohol Rev. 2017 Mar;36(2):220-226. doi: 10.1111/dar.12412. Epub 2016 Jun 14.
Biological tests of drug use can be used to inform clinical and legal decisions and hold potential to provide evidence for epidemiological studies where self-reported behaviour may be unavailable or unreliable. We test whether hair can be considered as a reliable marker of cannabis exposure.
Hair samples were collected from 136 subjects who were self-reported heavy, light or non-users of cannabis and tested using GC-MS/MS. Sensitivity, specificity, positive predictive value and negative predictive value were calculated for five cannabinoids (tetrahydrocannabinol [THC], THC-OH, THC-COOH, cannabinol and cannabidiol). Samples also were segmented in 1 cm sections representing 1 month exposure and the correlation between amount of cannabinoid detected and self-reported cannabis consumption tested.
All five cannabinoids were detected. Seventy-seven percent of heavy users, 39% of light users and 0% of non-users tested positive for THC. The sensitivity of detection of THC was 0.77 (0.56-0.91) comparing heavy cannabis smokers with light and non-users, whereas the sensitivity of other cannabinoids generally was considerably lower. The positive and negative predictive value of detection of THC were 0.57 (0.39-0.74) and 0.91 (0.82-0.97), respectively. A correlation of 0.52 (P < 0.001) was observed between self-reported monthly cannabis use and THC.
Hair analysis can be used as a qualitative indicator of heavy (daily or near daily) cannabis consumption within the past 3 months. However, this approach is unable to reliably detect light cannabis consumption or determine the quantity of cannabis used by the individual. [Taylor M, Lees R, Henderson G, Lingford-Hughes A, Macleod J, Sullivan J, Hickman M. Comparison of cannabinoids in hair with self-reported cannabis consumption in heavy, light and non-cannabis users. Drug Alcohol Rev 2017;36:220-226].
药物使用的生物学检测可用于为临床和法律决策提供信息，并有可能为流行病学研究提供证据，因为自我报告的行为可能不可用或不可靠。我们测试头发是否可被视为大麻暴露的可靠标志物。
从136名自我报告为大量、少量或不使用大麻的受试者中收集头发样本，并使用气相色谱-串联质谱法（GC-MS/MS）进行检测。计算了五种大麻素（四氢大麻酚[THC]、THC-OH、THC-COOH、大麻酚和大麻二酚）的敏感性、特异性、阳性预测值和阴性预测值。样本还被分成代表1个月暴露的1厘米长的小段，并检测所检测到的大麻素量与自我报告的大麻消费量之间的相关性。
检测到了所有五种大麻素。77%的大量使用者、39%的少量使用者和0%的不使用者THC检测呈阳性。将大量大麻吸烟者与少量使用者和不使用者进行比较，THC检测的敏感性为0.77（0.56 - 0.91），而其他大麻素的敏感性通常要低得多。THC检测的阳性预测值和阴性预测值分别为0.57（0.39 - 0.74）和0.91（0.82 - 0.97）。自我报告的每月大麻使用量与THC之间的相关性为0.52（P < 0.001）。
头发分析可作为过去3个月内大量（每日或接近每日）大麻消费的定性指标。然而，这种方法无法可靠地检测少量大麻消费或确定个体使用的大麻数量。[泰勒M，李斯R，亨德森G，林福德-休斯A，麦克劳德J，沙利文J，希克曼M。大量、少量和不使用大麻者头发中大麻素与自我报告的大麻消费的比较。《药物与酒精评论》2017年；36：220 - 226]
