Background Domiciliary non-invasive ventilation (DNIV) is established treatment for chronic hypercapnic ventilatory failure due to obesity hypoventilation syndrome (OHS) or chronic obstructive pulmonary disease (COPD).  DNIV concordance is defined as ?4 hours/night use for 70% of nights.  It is unclear whether cognitive impairment affects concordance with DNIV.

Aim To assess cognitive performance in non-concordant DNIV patients.

Methods Single site prospective service evaluation.  Cognitive objective measures, Montreal Cognitive Assessment (MoCA) and Addenbrooke?s Cognitive Examination (ACE-III), were completed for non-concordant DNIV patients with OHS and COPD.

Results Eleven participants (male: 4), mean(±SD) age (years) 62.18(±10.98) participated.  Diagnosis: OHS (n=6), COPD (n=3), COPD-OSA overlap syndrome (n=2).  Mean (±SD) cognitive function scores: MoCA 24(±3.35), ACE-III 85.1(±10.0).  63.6% (n=7) scored below the cut off scores for suspected cognitive impairment.

Mean(±SD) time(mm:ss) to complete MoCA: 9:41(±1:14) and ACE-III: 18:20(±13:55), with mean difference in completion time: 8:39 (p=0.03).

Conclusion MoCA and ACE-III independently detected potential cognitive impairment in our small cohort, which could impact on DNIV concordance. Both cognitive impairment screening tools can be used in clinical practice, ACE-III provides more detail, but MoCA is quicker to complete.