Eyelash Epilation in the Absence of Trichiasis: Results of a Population-Based Prevalence Survey in the Western Division of Fiji

Background
The WHO definition of trachomatous trichiasis (TT) is “at least one eyelash touching the globe, or evidence of recent epilation of in-turned eyelashes”, reflecting the fact that epilation is used as a self-management tool for TT. In Fiji’s Western Division, a high TT prevalence (8.7% in those aged ≥15 years) was reported in a 2012 survey, yet a 2013 survey found no TT and Fijian ophthalmologists rarely see TT cases. Local anecdote suggests that eyelash epilation is a common behaviour, even in the absence of trichiasis. Epilators may have been identified as TT cases in previous surveys.
Methods
We used a preliminary focus group to design an interview questionnaire, and subsequently conducted a population-based prevalence survey to estimate the prevalence of epilation in the absence of trichiasis, and factors associated with this behaviour, in the Western Division of Fiji.
Results
We sampled 695 individuals aged ≥15 years from a total of 457 households in 23 villages. 125 participants (18%) reported epilating their eyelashes at least once within the past year. Photographs were obtained of the eyes of 121/125 (97%) individuals who epilated, and subsequent analysis by an experienced trachoma grader found no cases of trachomatous conjunctival scarring or trichiasis. The age- and sex- adjusted prevalence of epilation in those aged ≥15 years was 8.6% (95% CI 5.7–11.3%). iTaukei ethnicity, female gender, and a higher frequency of drinking kava root were independently associated with epilation.
Conclusion
Epilation occurs in this population in the absence of trichiasis, with sufficient frequency to have markedly inflated previous estimates of local TT prevalence. Individuals with epilated eyelashes should be confirmed as having epilated in-turned eyelashes in an eye with scarring of the conjunctiva before being counted as cases of TT.

### 背景
世界卫生组织（WHO）对沙眼性倒睫（trachomatous trichiasis, TT）的定义为「至少有一根睫毛接触眼球，或存在近期内翻睫毛拔除（epilation）的证据」，该定义契合了睫毛拔除作为沙眼性倒睫自我管理手段的临床事实。2012年的一项调查显示，斐济西部分区的沙眼性倒睫患病率较高（15岁及以上人群中占8.7%），但2013年的同类调查却未发现任何沙眼性倒睫病例，且斐济眼科医师也极少接诊此类病例。当地临床轶事显示，即便不存在倒睫问题，睫毛拔除也是一种常见行为。此前的调查可能将接受过睫毛拔除的个体误判为沙眼性倒睫病例。

### 方法
我们首先通过初步焦点小组访谈设计了调研问卷，随后开展基于人群的患病率调查，以评估斐济西部分区人群在无倒睫情况下的睫毛拔除行为患病率，以及与该行为相关的影响因素。

### 结果
我们从23个村庄的457户家庭中抽样纳入695名15岁及以上的研究对象。其中125名参与者（占比18%）报告称在过去一年内至少有过一次睫毛拔除行为。我们为其中121名（占睫毛拔除人群的97%）参与者拍摄了眼部照片，经经验丰富的沙眼分级医师后续分析，未发现任何沙眼性结膜瘢痕或倒睫病例。经年龄与性别校正后，15岁及以上人群的睫毛拔除患病率为8.6%（95%置信区间：5.7%~11.3%）。伊陶凯族（iTaukei）裔、女性身份以及饮用卡瓦根的频率更高，均与睫毛拔除行为存在独立相关性。

### 结论
本研究人群中存在无倒睫前提下的睫毛拔除行为，且该行为的发生频率足以显著高估此前当地的沙眼性倒睫患病率。在将睫毛拔除病例归类为沙眼性倒睫病例之前，应确认其为伴有结膜瘢痕的内翻睫毛拔除病例。