Use of a new ALS specific respiratory questionnaire: the ARES score

Objective: To develop an ALS respiratory symptom scale (ARES) and evaluate how ARES compares to Medical Research Council Modified Dyspnea Scale (MRC), Borg dyspnea scale, and respiratory subscores from ALSFRS-R (ALSFRS-Resp) in detecting respiratory symptoms, correlation with pulmonary function and ALSFRS-R, and deterioration of pulmonary function and ALSFRS-R over time. Methods: The ARES scale consists of 9 questions addressing dyspnea during activities and 3 questions addressing symptoms of worsening pulmonary function. 153 subjects with ALS completed MRC, Borg, ALSFRS-R, and ARES questionnaires at baseline, 16, 32, and 48 weeks, and spirometry at baseline. 73 of these subjects had spirometry, maximum inspiratory (MIP) and expiratory pressures (MEP), nasal inspiratory pressure (SNIP), and maximum voluntary ventilation (MVV) measured at each visit. Sensitivity of each scale and correlations between symptom scores, pulmonary function, and ALSFRS-R were evaluated at baseline and over the study duration. Results and conclusions: ARES was more sensitive than MRC, Borg and ALSFRS-Resp scales at baseline and for detecting changes at 16 and 32 weeks. ARES and ALSFRS-Resp correlated significantly with vital capacity at baseline, but Borg and MRC did not. Only ALSFRS-Resp correlated with respiratory pressures. Changes in ALSFRS-Resp and ARES both correlated with vital capacity decline; however, changes in ARES had superior correlation with respiratory pressure decline. Comparisons between telephone and in-person administration of ARES met criteria for satisfactory test-retest correlation in different settings one week apart. These findings suggest that the ARES may be more useful in monitoring symptom progression in ALS than other available scales.