T.p.25

McArdle disease is associated with muscle cramps caused by everyday activity and exercise. Secondary complications include reduced activity, fatigue and psychological distress. Incidence of obesity, cardiovascular disease and diabetes is also increased. A multidisciplinary approach is recommended for management of the condition and to address the secondary complications. Key outcome measures are the 12 min walk test (12MWT) and quality of life (SF-36v2). This poster reports the results of two outcome measures used routinely within the National McArdle multi-disciplinary service. Hypothesis is that attending the service will result in gains on these two measures. 74 patients completed the 12MWT on at least one occasion. 25% of patients had severe impairment, walking less than 500 m. 51% had mild impairment walking 500–800 m. 24% managed over 800 m. 65 patients completed the SF36v2. Patients scored below the normative comparison group on all subscales. There was correspondence between results on the 12MWT and SF-36v2. Patients with severe impairment had lower scores on the SF-36v2. 45 patients repeated the 12MWT. Average performance improved by 101 m (SD 186 m, range −290 to + 645). 13 patients also repeated the SF36v2. Scores improved significantly particularly in emotional and mental health, vitality and social functioning. This corresponded with an average increase of 185 m on the 12MWT. There is wide variation in performance on the 12MWT. Patients report significantly poorer physical and mental health on the SF-36v2. A poorer performance on the 12MWT corresponds with lower scores on the SF-36v2. There is a significant improvement on both outcome measures following intervention from the multi-disciplinary team. In summary, patients with McArdle disease may benefit from a multidisciplinary approach to reduce physical disability and improve psychological well-being. This study supports the use of the 12MWT and SF-36v2 as outcome measures for this population.