Weather Only Has Small Impact on Psoriatic Arthritis Symptoms

Maxine Joly-Chevrier

Credit: Canadian Medical Association

People did not experience clinically significant differences in their psoriatic arthritis (PsA) between summer and winter weather, although differences were observed.¹

“It was previously shown that cutaneous lesions of psoriasis patients may do better in certain seasons like summer or winter. However, to date, PsA studies assessing the impact of weather variation on disease activity are very limited, near non-existent. Investigating the correlation between DA, PROs and weather variation in PsA can provide valuable insights into its disease mechanisms to improve patients' quality of life,” lead investigator Maxine Joly-Chevrier, MD Candidate, University of Montreal, Quebec, Canada, and colleagues wrote.¹

Joly-Chevrier and colleagues matched hourly data on temperature, relative humidity, and pressure between 2015 to 2020 from Montreal (Environment Canada) with disease activity (DA) and patients reported outcomes (PROs) of patients with PsA patients enrolled in RHUMADATA patient registry. They compared the difference in mean DA and between winter and summer and calculated Pearson Correlation Coefficients between clinical profile and weather measurements.

The investigators collected 2665 PROs from a total of 858 patients with PsA. Among DA/PRO data collected, only clinical disease activity index (CDAI) scores (mean, 8.2; standard deviation [SD], 7.8) and simplified disease activity index (SDAI) scores (mean, 8.6; SD, 7.6) were lower in winter compared to summer (CDAI [mean, 8.8; SD, 7.9; P = .001]; SDAI [mean, 9.5; SD, 8.0; P <.001]).¹

Joly-Chevrier and colleagues found that summer revealed positive correlations between humidity and scores on patient global assessment (PtGA), fatigue, pain, c- reactive protein (CRP), bath ankylosing spondylitis disease activity index (BASDAI), and bath ankylosing spondylitis functional index (BASFI) and negative correlations between temperature and health assessment questionnaire disability index (HAQ-DI) scores. Winter had positive correlations between temperature, fatigue, and pain.

However, the investigators found significant correlations between gender, age, and disease duration, and optimal regression models derived based on Akaike's Information Criteria suggested that weather may account for less than 1% of the variation in PROs, which may reflect disease activity.

“In conclusion, our study contributes to the growing body of evidence that challenges the direct association between weather conditions and IADs symptomatology, which are complex diseases influenced by multiple factors. Our findings suggest that weather-related factors play a limited role at the group level in the variability of PsA symptoms and that other factors may be more influential. However, at the individual level, some patients may experience a more significant impact from weather-related factors,” Joly-Chevrier and colleagues concluded.¹

Other recent research into PsA found that patinets did not have notable differences in clinical parameters before initiating biologic (b) and targeted synthetic (ts) disease modifying anti-rheumatic drugs (DMARDs) mono or methotrexate (MTX)-combination therapy and treatment decisions were driven by subjective tolerability of MTX.²

The combination group had a mean drug retention time of 15.2 months and the monotherapy group had a mean drug retention time of 14.4 months. At 6 months, 48% of the combination group and 66% of the monotherapy group were still on their original treatment; at 12 months, these proportions were 48% and 67%, respectively. Adjusted treatment retention rates were found to be similar between groups (P = .04).²

REFERENCES

1. Joly-Chevrier M, Coupal L, Sauvageau LC, Movahedi M, Choquette D. A Real-World Analysis on Weather Variation Disease Activity and Patient Reported Outcomes in Psoriatic Arthritis. J Rheumatol. Published online September 15, 2024. doi:10.3899/jrheum.2024-0520. [Epub ahead of print].

2. Regierer AC, Kiefer D, Schett D, et al. No difference in clinical parameters and drug retention in PsA patients receiving b/tsDMARD monotherapy versus combination with methotrexate: data from the RABBIT-SpA registry. RMD Open 2024;10:e004389. doi: 10.1136/rmdopen-2024-004389