Abstract: Background - Chiari-like malformation (CM) and syringomyelia (SM) are prevalent among Cavalier King Charles Spaniels (CKCS). Sleep disturbances are common in people with this malformation; however, no studies have investigated whether symptomatic CKCS experience these. Hypothesis/Objectives - We hypothesized that CKCS with symptomatic CM+/-SM exhibit sleep disturbances. Animals - Thirty nine CKCS with and without symptomatic CM+/-SM were included. All dogs slept in the same room as their owners. Methods - Questionnaire-based study conducted using 2 validated questionnaires: CHASE for severity of CM+/-SM signs, and SNoRE 3.0 for evaluation of sleep disturbances. Dogs with a CHASE score of 7 or greater were classified symptomatic for CM+/-SM. SNoRE 3.0 scores were compared between symptomatic and asymptomatic dogs using the Wilcoxon rank sum test. Results - There were 19 symptomatic dogs aged 3-10 years (8 males, 11 females), and 20 asymptomatic dogs aged 1-10 years (8 males, 12 females). The mean CHASE score for symptomatic dogs was 12.32 (median: 13.0, range: 7-18) and asymptomatic dogs was 1.85 (median: 1, range: 0-6). The total SNoRE score for symptomatic dogs had a median of 10 (range: 6-30), while asymptomatic dogs had a median of 6 (range: 6-23). Significant differences were found between the groups comparing total SNoRE score, sleep quality, and sleep interruptions (p=0.0016, 0.0052, and 0.0009 respectively). Conclusions and Clinical Importance - CKCS with symptomatic CM+/-SM exhibit owner-reported signs of sleep disturbances. Confirmation using polysomnography is warranted and sleep should be considered in the therapeutic plan.
