Background/Purpose:

Inflammatory myositis (IM) is extremely rare in white middle-aged males. Incidence rates in males ranging from 0.25 to 5 per million. We describe a series of Fire Department of the City of New York (FDNY) firefighters who developed IM following World Trade Center (WTC) exposures.

Methods:

FDNY WTC-exposed firefighters with IM are followed jointly by the WTC Health Program at FDNY and the Rheumatology Division at the New York University, School of Medicine. Patient demographics, WTC-exposure information, smoking status, diagnoses (including date of diagnosis), and pulmonary findings were obtained from FDNY’s WTC database. Findings (symptoms, duration, muscles involved, treatments, and response) were obtained from chart review.

 

Results:

Seven firefighters developed IM after WTC-exposure. Duration from WTC-exposure to IM diagnosis was 4.6 years (IQR=1.5-6.2). The average annual incidence rate was 9.2 per million. No cases had been reported at FDNY pre-9/11/01 (15 year prior database search).  All were white males who arrived at the WTC-site within two weeks after 9/11/01. Three cases are never smokers, while four cases are ever-smokers. None had a family history of IM or autoimmune disease. Their median age on 9/11/01 was 45.5 years (IQR = 43.2-55.6), with a median of 20 years (IQR=15.8-31.0) of FDNY firefighting service pre-9/11/01. All presented with bilateral proximal muscle weakness and pain most noticeable in the pelvic girdle and quadriceps, and elevated creatine kinase. None had skin involvement; one patient developed interstitial lung disease (anti-Jo antibodies) and died two years after lung transplantation; and one patient had inclusion body myositis (IBM) on muscle biopsy. All but two patients responded to corticosteroids and methotrexate with dramatic improvement and one patient had complete resolution without need for maintenance medication. Two patients (one with anti-Jo antibodies and one with IBM) required monthly intravenous immunoglobulin.   

Conclusion:

The incidence of IM appears to be increased in male FDNY firefighters after WTC-exposure, however further studies are needed to confirm this. Additionally, studies are needed in order to determine the generalizability of these findings to other groups with varying levels of WTC-exposure or with non-WTC environmental/occupational exposures.

---

« Back to 2013 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/inflamamatory-myositis-increased-incidence-in-fire-department-of-new-york-firefighters-after-world-trade-center-exposure/