McLarty J W, Holiday D B, Girard W M, Yanagihara R H, Kummet T D, Greenberg S D
Department of Epidemiology/Biomathematics, University of Texas Health Center at Tyler 75710, USA.
Am J Clin Nutr. 1995 Dec;62(6 Suppl):1431S-1438S. doi: 10.1093/ajcn/62.6.1431S.
A randomized, placebo-controlled clinical trial of beta-carotene and retinol was conducted with 755 former asbestos workers as study subjects. The targeted endpoint for the intervention study was a reduction in the incidence and prevalence of sputum atypia. The dosage of 50 mg beta-carotene/d and 25,000 IU retinol/d on alternate days resulted significant increases in serum concentrations of both agents with no clinically significant toxicity. Skin yellowing was observed in approximately 35% of patients and may have contributed adversely to protocol adherence. Baseline analysis revealed that smoking and drinking were associated with lower concentrations of serum beta-carotene, even after dietary carotene intake was adjusted for (P < 0.0001). Baseline concentrations of retinol were apparently lowered by smoking (P < 0.002) and increased by drinking (P < 0.0001). Drinking and smoking also were significantly related to lower beta-carotene concentrations after supplementation (P < 0.001). No significant reduction in sputum atypia was observed after treatment.
以755名曾接触石棉的工人为研究对象，开展了一项β-胡萝卜素和视黄醇的随机、安慰剂对照临床试验。干预研究的目标终点是降低痰异型细胞的发生率和患病率。每隔一天服用50毫克β-胡萝卜素/天和25,000国际单位视黄醇/天的剂量，导致两种物质的血清浓度显著升高，且无临床显著毒性。约35%的患者出现皮肤发黄，这可能对方案依从性产生了不利影响。基线分析显示，即使在调整饮食中胡萝卜素摄入量后，吸烟和饮酒仍与血清β-胡萝卜素浓度较低有关（P < 0.0001）。吸烟明显降低了视黄醇的基线浓度（P < 0.002），而饮酒则使其升高（P < 0.0001）。饮酒和吸烟也与补充后较低的β-胡萝卜素浓度显著相关（P < 0.001）。治疗后未观察到痰异型细胞有显著减少。
