Oral Presentation 46th Annual ARA NSW-ACT Branch Meeting 2024

Background
Australia’s vastness and variable population density makes accessing specialised healthcare a challenge, particularly for those with rare diseases managed in tertiary centres. Systemic sclerosis (SSc) is a rare connective tissue disease, with high morbidity and mortality. We investigated differences in distance from hospitals, disease characteristics and outcomes for SSc patients from rural and metropolitan areas.

Methods
Patients enrolled in the Australian Scleroderma Cohort Study (ASCS) (1), with a valid address, who met EULAR/ACR criteria for SSc were included. Euclidean distance from residential address to ASCS enrolment site was calculated. The ABS Remoteness Areas were dichotomised into metropolitan and rural (inner, outer regional, remote, very remote). Demographic characteristics, disease profile and quality of life were compared between rural and metropolitan patients, using univariate tests. The effect of rurality on survival was demonstrated using a Kaplan-Meier curve, and factors that affect mortality were adjusted for with a Cox proportional hazards model.

Results
Of the 1894 patients included, 1308 (69%) were metropolitan, and 586 (31%) were rural, living on average 135km from their enrolment site (vs 13km). A larger proportion of rural patients were Caucasian (95.2% vs 88.3%, p<0.001) and lower proportion female (82.8% vs. 86.8%, p=0.02). Rural patients had less diffuse disease (21.8% vs 27.8%, p=0.007), and more pulmonary arterial hypertension (PAH), at enrolment (9.2% vs 5.4% p=0.002), and overall. Whilst SF-36 median physical component summary score was lower in rural patients (31.6 vs 33.6, p=0.003), the mental component score was higher (41.5 vs 39.7, p=0.008). Rural patients also had a higher Damage Index score (5.0 vs 4.0, p<0.001), but a similar Activity Index score. Rural patients had higher all-cause mortality (p=0.025), which was maintained when other covariates that affect survival (gender, diffuse disease, PAH, disease duration, age at onset and FVC) were considered, with a hazard ratio of 1.48 (1.22 to 1.82, p<0.001).

Conclusion
Despite similarities in disease activity, rural patients experienced worse all-cause mortality and as expected, travelled significant distances to receive care at their ASCS centre. Rural patients had more PAH on enrolment into the ASCS, possibly reflecting a referral bias for those diagnosed with PAH, or suboptimal screening for PAH in less well-resourced geographical areas. Further research could focus on the impact of geographic health accessibility on SSc patients, and the ideal placement of rheumatology services or virtual care models. Research on factors to facilitate screening for PAH in regional settings may be beneficial.