Aims The primary aims of this study were to identify the rates of employment (defined as the number of people in paid employment) and factors influencing work performance in adults with myotonic dystrophy. The secondary aim was to determine time loss from work due to their health.

Study Design This cross-sectional study drew upon data collected from a broader study exploring the prevalence and outcomes of genetic muscle disorders in New Zealand (MD-Prev). This study extracted the demographic, diagnostic and questionnaire data for adults (aged ≥16 years) diagnosed with myotonic dystrophy type 1 and 2 from the MD-Prev database.

Participants The MD-Prev study identified 327 adults with a confirmed diagnosis of myotonic dystrophy in New Zealand. They were all invited to participate in a multi-domain assessment, and 202 participants consented.

Outcome Measures The Work Limitations Scale (WLQ-25) was used to measure work performance. Personal, occupational and environmental factors were considered in the analysis of work performance. This holistic view included measures to address self-efficacy, mood, cognition, physical functioning, pain, fatigue, sleep and support. A Spearman correlation helped identify factors associated with work performance. A Mann-Whitney U test compared data between those employed and unemployed to determine if there was a significant difference between these groups that could explain employment status. A chi-square test compared age, gender, ethnicity, and type of myotonic dystrophy between participants and non-consenters.

Results Out of 202 participants, only 69 were employed at the time of the study. Despite a low employment rate, 73% had not taken time off work due to their health in the previous fortnight. Physical and mental-interpersonal demands of a job affected work performance for 62.1% and 57.4% of the sample. Over 50% of those working reported no difficulty in time management (56.7%), and work-output (55.9%), which indicates participants are performing well in certain aspects of their job demands. Pain and fatigue impacted significantly on meeting work demands followed by depression, cognition, sleep, and physical functioning. Age, gender and ethnicity did not influence employment status. However, there was a significant difference in ethnicity between those who did and did not participate in the assessments suggesting caution in the representation of findings for people of non-European ethnicity. Participants who completed tertiary education had a greater chance of employment with 56.5% of them in professional roles.

Conclusion This study builds on previous research and highlights that people with myotonic dystrophy are a minority group in the New Zealand labour sector. Work performance was most disturbed at the physical level, with fatigue and pain being the main factors influencing all domains of work performance. Addressing pain and fatigue management in addition to symptoms of depression, cognition and environmental barriers may facilitate work performance and productivity. Encouragingly many people employed in this study were performing well in most aspects of their role. These findings may provide insight for health professionals, disability services, and employers when supporting a person with myotonic dystrophy into sustainable careers that will accommodate their long-term capabilities as their condition progresses.