Patient-reported symptoms are associated with clinically impactful changes in systemic sclerosis( SSc ) disease activity, according to findings published in Arthritis Care & Research. “Quantifying disease activity in systemic sclerosis (SSc) remains challenging due to the complex etiopathogenesis of the disease; and a disease course that lacks clear clinical relapses; and validated measures of various aspects of disease activity,” Laura Ross, MBBS, FRACP,of St. Vincent’s Hospital, in Melbourne, Australia, and colleagues wrote.
“These factors and the episodic nature of certain disease manifestations mean evaluating disease status; is often reliant upon patient-reported symptoms.” To determine the association between patient-reported symptoms and changes in SSc disease activity over time; Ross and colleagues studied data from 1,636 patients in the Australian Scleroderma Cohort Study.
Modified Rodnan skin score
The researchers used generalized estimating equations to search for the relationship; between patient-reported worsening of Raynaud’s phenomenon, skin involvement and breathlessness during the month prior to each study visit; as well as disease activity characteristics in organ systems. Associations studied by the researchers included patient-reported worsening of Raynaud’s phenomenon; and new-onset digital pitting and digital ulcers, patient-reported worsening skin involvement and increased modified Rodnan skin score; new skin involvement and new-onset joint contractures.
Ross and colleagues also examined patient-reported worsening breathlessness; and worse respiratory functions test results, new-onset interstitial lung disease and new-onset pulmonary arterial hypertension. But using data from 1,636 patients enrolled in the Australian Scleroderma Cohort Study, they use generalised estimating equations to determine the relationship between patient‐reported worsening of Raynaud phenomenon (RP), skin involvement and breathlessness in the month preceding each study visit and features of disease activity in the corresponding organ systems.
But according to the researchers, there was a significant association between patientreported worsening Raynaud’s phenomenon and the presence of digital ulcers (OR = 1.53; 95% CI, 0.60.93), as well as patientreported worsening skin involvement and increasing modified Rodnan skin score (OR = 2.1; 95% CI,1.542.86).
In addition, worsening patient breathlessness was significantly associated with deteriorating respiratory functions test results, reflecting a 10% decrease in forced vital capacity (OR = 2.12; 95% CI,1.72.65) and a 15% worsening in diffusing capacity of carbon monoxide (OR = 1.97; 95% CI,1.342.02). Worsening patient breathlessness also significantly associated with newonset interstitial lung disease (OR = 1.91; 95% CI, 1.42.61) and newonset pulmonary arterial hypertension (OR = 5.08; 95% CI, 3.597.19).
“When serial data of objective measures of disease activity over time are not available patient-reported changes in skin and [Raynaud’s phenomenon] may be substituted for objective indicators of worsening disease activity,” Ross and colleagues wrote. “Whilst worsening dyspnea lacks specificity for a particular disease process, the strong association of worsening breathlessness and clinically meaningful deterioration of [respiratory function tests] and the new diagnosis of lung parenchymal and pulmonary vascular disease suggests it too has a role in the subjective assessment of SSc-disease activity.”