A Hidden Trigger for Giant Cell Arteritis?

TOPLINE:

Exposure to environmental particulate matter ≤ 10 μm in diameter (PM₁₀) is associated with an increased risk for giant cell arteritis, particularly in older individuals aged ≥ 70 years and those with prolonged exposure to high levels of air pollution.

METHODOLOGY:

• Researchers conducted a retrospective case-crossover study to examine the association between exposure to airborne PM₁₀ and the risk for giant cell arteritis and its ischemic complications.
• They included 232 patients with giant cell arteritis (median age at diagnosis, 73 years; 69% women) from three hospitals in northern Italy between June 2013 to December 2021.
• The hourly and daily average concentrations of PM₁₀ were collected from the Italian monitoring network; patients’ exposure to PM₁₀ was calculated using a space-time statistical model, incorporating meteorological variables, elevation, and proximity to main roads.
• The mean follow-up time of this cohort was 38 months.

TAKEAWAY:

• Every 10 μg/m³ increase in PM₁₀ exposure in the preceding 60 days increased the incremental risk (IR) for giant cell arteritis by 27.1% (95% CI, 5.8-52.6).
• This association was more pronounced (IR, 38.8%; 95% CI, 9.2-76.3) in the subgroup of patients aged ≥ 70 years.
• The positive association between incident giant cell arteritis and concentrations of PM10 was seen only when patients were exposed to high concentrations of PM₁₀ (26.9 ± 13.8 μg/m³) but not low concentrations (11.9 ± 7.9 μg/m³).
• This study did not show any significant association between exposure to PM₁₀ and ischemic complications.

IN PRACTICE:

“Exposure to PM₁₀ in the 60 days preceding [giant cell arteritis] symptoms onset seems to be associated with an increased risk of developing the disease, especially in older individuals with prolonged exposure to high levels of air pollution,” the authors wrote.

SOURCE:

The study was led by Milena Bond, MD, Hospital of Bruneck, Teaching Hospital of the Paracelsus Medical University, Brunico, Italy, and was published online on July 16, 2024, in Arthritis Care & Research.

LIMITATIONS:

The retrospective nature of the study may have introduced recall bias. The study did not include data for other particulate matter fractions or gaseous pollutants, which may have impacted the findings. The use of residential addresses at the time of diagnosis precluded assessment of potential recent relocations.

DISCLOSURES:

This study did not disclose any funding source. Some authors reported having financial relationships with multiple pharmaceutical companies.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.