Short‐term effects of smoking marijuana on balance in patients with multiple sclerosis and normal volunteers

A double‐blind randomized placebo‐controlled study of inhaled marijuana smoke on postural responses was performed in 10 adult patients with spastic multiple sclerosis (MS) and 10 normal volunteers matched as closely as possible for age, sex, and weight. A computer‐controlled dynamic posturographic platform with a video line scan camera measured shoulder displacement in response to pseudorandom platform movements. Premarijuana smoking patient tracking was inferior to that of the normal volunteers as indicated by the higher noise variance of the former. Smoking one marijuana cigarette containing 1.54% Δ9‐tetrahydrocannabinol increased postural tracking error in both the patients and normal control subjects with both eyes open and closed; this untoward effect was greatest for the patients. The tracking error was also accompanied by a decrease in response speed for the patients with their eyes closed. Marijuana smoking further impairs posture and balance in patients with spastic MS.

对10名成年痉挛性多发性硬化症（MS）患者和10名在年龄、性别和体重上尽可能匹配的正常志愿者进行了一项吸入大麻烟对体位反应的双盲随机安慰剂对照研究。一个带有视频线扫描相机的计算机控制的动态姿势描记平台测量了对伪随机平台运动的肩部位移。吸食大麻前患者的追踪能力不如正常志愿者，前者的噪声方差更高表明了这一点。吸食一支含1.54%Δ9 - 四氢大麻酚的大麻烟会增加患者和正常对照者在睁眼和闭眼时的体位追踪误差；这种不良影响在患者中最为显著。对于闭眼的患者，追踪误差还伴随着反应速度的降低。吸食大麻进一步损害痉挛性MS患者的姿势和平衡。