Abstract Details

The most common symptoms of iSS are hearing impairment followed by imbalance, which gradually decline over time. Multifunctional involvement (particularly hearing) is likely to adversely impact QoL in iSS but has not been studied previously.

To assess the quality of life (QoL) in classical (infratentorial) superficial siderosis (iSS)

This anonymous online survey included generic QoL questionnaires HUI3 and EQ5D-5L (UK tariff). Following Ethics approval, the study information was distributed to dedicated patient groups, organisations and charities. Participants were asked to confirm they were of ≥18 years old, confirmed they had been diagnosed with iSS, and consented to participating in the study. They were then able to proceed to study-specific questions and questionnaires, presented in fixed order.

We included 51 participants: 31(61%) were male; mean (± standard deviation, SD) age was 57.9(±12.1) years; median (interquartile range, IQR) disease duration (time from likely causative event to survey, known in 33 cases) was 22.0(28.0) years. The multi-attribute scores(n=50) were: mean(±SD) 0.36(±0.45) for HUI3 and median(IQR) for EQ5D-5L 0.64(0.33), and were statistically significantly different between the two instruments (mean ranks, z=4.85; p<0.001). The disease-duration correlated (as assessed by Kendall’s tau-b, ?_b) with HUI3 scores (?_b(33)=-.268, p=0.033), but not EQ5D-5L (?_b(33)=-.245, p=0.051). The HUI3 Hearing domain scores correlated with HUI3 (?_b(50)=.650, p<0.001) and EQ5D-5L (?_b(50)=.323, p<0.001) multi-attribute scores. Most frequently affected domains (moderate or worse category) were Hearing/Pain for HUI3 (32(64%) and 24(48%), respectively) and Mobility/Pain  for EQ5D-5L (27(54%) and 25(50%), respectively).

The QoL scores in iSS are low, indicating a major adverse impact comparable to Motor Neuron Disease (EQ5D-5L). HUI3 QoL instrument that includes Hearing domain – correlates with disease-duration and possibly better reflects the QoL in iSS, by capturing lower multi-attribute scores. We suggest that QoL measure such as HUI3 should be used in future clinical and research studies on iSS.