Abiose A, Jones B R, Cousens S N, Murdoch I, Cassels-Brown A, Babalola O E, Alexander N D, Nuhu I, Evans J, Ibrahim U F
Department of Ophthalmology, Ahmadu Bello University, Kaduna, Nigeria.
Lancet. 1993 Jan 16;341(8838):130-4. doi: 10.1016/0140-6736(93)90002-x.
The safety and efficacy of ivermectin in the prevention of blindness from onchocerciasis have been established in many studies that have addressed the drug's effects on the front of the eye. We undertook a study with sufficient statistical power to detect an effect on optic nerve disease (OND), probably the main cause of blindness in the disorder. The trial was based in 34 mesoendemic communities in Kaduna State, Nigeria. Villagers aged 5 years and older were randomly assigned annual dosing with ivermectin or placebo for 3 years. Participants underwent medical and ophthalmological examinations before the first, third, and fourth treatments. 3522 villagers aged 15 and older were re-examined at least once. Skin-snip samples were taken at baseline for calculation of microfilarial load. The outcome measure was development of disc pallor accompanied by objective evidence of deterioration in visual function; 116 subjects (45 ivermectin-treated, 71 placebo-treated) showed such changes during the trial. The incidence rate ratio (ivermectin vs placebo) was 0.90 (95% CI 0.54-1.51) for subjects with loads of 0-10 mf (microfilariae) per mg skin and 0.52 (0.29-0.93) for subjects with more than 10 mf/mg. The incidence rate ratio varied little when account was taken of age, sex, presence of pre-existing disc pallor in one eye, previous use of diethylcarbamazine citrate, or doses of ivermectin or placebo received. There was evidence that ivermectin reduced the incidence of OND in subjects with microfilarial loads above 10 mf/mg but had little effect in those with lower loads. Sustained annual delivery of ivermectin could prevent a substantial proportion of onchocercal blindness in mesoendemic communities.
许多研究探讨了伊维菌素对眼部前部的影响，证实了其在预防盘尾丝虫病致盲方面的安全性和有效性。我们开展了一项具有足够统计学效力的研究，以检测其对视神经疾病（OND）的影响，OND可能是该疾病致盲的主要原因。该试验在尼日利亚卡杜纳州的34个中度流行社区进行。5岁及以上的村民被随机分配，每年接受伊维菌素或安慰剂治疗，为期3年。参与者在首次、第三次和第四次治疗前接受医学和眼科检查。对3522名15岁及以上的村民至少进行了一次复查。在基线时采集皮肤切片样本以计算微丝蚴负荷。结局指标是视盘苍白的出现，并伴有视觉功能恶化的客观证据；116名受试者（45名接受伊维菌素治疗，71名接受安慰剂治疗）在试验期间出现了此类变化。每毫克皮肤中微丝蚴负荷为0 - 10条（微丝蚴）的受试者，发病率比（伊维菌素与安慰剂）为0.90（95%置信区间0.54 - 1.51），微丝蚴负荷超过10条/毫克的受试者为0.52（0.29 - 0.93）。考虑年龄、性别、一只眼睛是否存在既往视盘苍白、既往是否使用枸橼酸乙胺嗪或接受的伊维菌素或安慰剂剂量时，发病率比变化不大。有证据表明，伊维菌素可降低微丝蚴负荷高于10条/毫克的受试者中OND的发病率，但对负荷较低的受试者影响不大。持续每年使用伊维菌素可预防中度流行社区中相当一部分盘尾丝虫病致盲病例。
