The Longitudinal Impact of Macular Telangiectasia (MacTel) Type II on Vision-Related Quality of Life: The MacTel Study

摘要

Purpose: : To determine the long-term effects of Macular Telangiectasia Type II (MacTel) on overall and specific aspects of Quality of Life (QoL) using the Impact of Vision Impairment (IVI) questionnaire. Methods: : Individuals aged 18 years or older with a clinical diagnosis of MacTel were invited to participate in the MacTel study. The MacTel study is an international, multi-centred, 5 year observational study. The diagnosis of MacTel was determined using fundus photography, ocular coherence tomography (OCT), fluorescence angiogram and autofluorescence, which was later confirmed by the Fundus Reading Centre of Moorefielda??s Eye Hospital. LogMAR best-corrected visual acuity (BCVA) was obtained and QoL was assessed using the IVI questionnaire, which consists of 28 items and 3 subscales, including reading and assessing information, mobility and independence and emotional well-being. Rasch analysis was used to validate the IVI questionnaire. A control group consisting of 10 males and 14 females (mean age = 53.1 years) with no vision impairment (Log MAR 0.2) were also recruited. Results: : At baseline, and 12 months, 23 MacTel patients (14 females), with a mean age=62.6 years, were examined. Initial analysis showed that the IVI fitted the Rasch model, suggesting that it has valid and unidimentional properties for use in this sample At baseline, the control group had significantly better overall QoL (mean?±SD = 5.52?±1.92) compared to the MacTel patients (mean?±SD: 2.08 ?±1.66, p0.001). Similar findings were found for the three IVI subscales. At the 12-month follow-up, we found no significant overall change in the overall IVI score and the three subscales compared to the baseline mean (2.06 ?±1.40 V.S 2.08, ?±1.66; p= 0.976 for overall score only). There was no significant difference for BCVA for either eye at post test in the Mac Tel group (baseline and 12 month follow-up VA = 71.70 and 68.45, respectively for left eye only, p= 0.496). Conclusions: : The IVI is a valid tool to evaluate and monitor vision-specific QoL in patients with MacTel. No significant changes in QoL parameters in MacTel patients were found after 1 year which was paralleled by our finding of no significant deterioration in vision at post-test. A longer mentoring period is required to evaluate the longitudinal impact of MacTel on vision-specific QoL.