To examine the extent patients with SMA and their caregivers report absence from work, reduced productivity while at work, and reduced productivity while doing regular daily activities using the Work Productivity and Activity Impairment (WPAI) Questionnaire.

Cure SMA asked their community members to complete the WPAI questionnaire in May 2018. The WPAI is a 7-item questionnaire used to assess the work productivity lost due to a specific health problem over the last 7 days.

            The majority (59.1%) of the questionnaires were completed by parents of a child with SMA.  41.5% of the questionnaires were completed by or on behalf of someone with type II SMA, followed by type III (34.0%), and then type I (19.5%). The overall scores were as follows: 37.2% presenteeism, 42.3% work productivity loss, and 55.3% daily activity loss due to SMA, which is greater than what has been observed in other diseases such as Duchenne muscular dystrophy. In the past 7 days, there was a statistically significant difference between the percentage of work time missed (absenteeism) due to SMA by parents of a child with SMA, 15.9%, and affected adults, 6.9%. The scores of presenteeism (impairment at work), work productivity loss, and impairment while performing regular daily activities due to SMA did not have a statistically significant difference between working adults with SMA and parents of a child with SMA.

The WPAI results show that the work missed due to SMA is greater for caregivers of those with SMA, but the overall loss of work and daily productivity is the same across those with SMA and their caregivers.