A NEW study revealed that the severity of Raynaud’s phenomenon, a common early manifestation of systemic sclerosis, is influenced significantly by ambient temperature. The study found that both very cold and very warm temperatures are associated with increased severity of Raynaud’s symptoms, highlighting the need for temperature considerations in clinical management and intervention trials.
Raynaud’s phenomenon is characterised by episodes of reduced blood flow to the fingers and toes, often triggered by cold exposure. The study aimed to map how varying temperatures impact the severity of these episodes across broad temperature ranges. Data from 2,243 participants, predominantly women (88%) with a mean age of 54.8 years, was collected from 20,233 self-reported assessments of Raynaud’s severity on a 0-10 scale. Temperature data for the week prior to each assessment were extracted from weather sites near the participants’ recruiting centres.
Results showed that Raynaud’s phenomenon severity was highest at extremely cold temperatures, with a maximum predicted severity score of 6.8 at -25°C. Severity decreased minimally from -15°C to 5°C, then declined more significantly between 5°C and 25°C, where the lowest severity score of 2.6 was observed. However, severity increased again at temperatures above 25°C, reaching 3.5 points at 35°C and 5.6 points at 40°C, suggesting that warm temperatures, possibly compounded by air conditioning, also exacerbate symptoms.
The study’s results show that Raynaud’s phenomenon is most severe in extreme cold but also worsens with high temperatures, which may be due to the use of air conditioning. These findings suggest that both cold and warm temperature management strategies should be considered in clinical care and when designing trials for Raynaud’s phenomenon interventions in patients with systemic sclerosis.
Aleksandra Zurowska, EMJ
Reference
Virgili-Geravis G et al. The association of outdoor temperature and self-reported Raynaud’s phenomenon severity among people with systemic sclerosis: a Scleroderma Patient-centered Intervention Network Cohort study. Lancet. 2024; DOI: 10.1016/S2665-9913(24)00189-9.
