A 36-year-old woman presents with pain, aching, stiffness, and swelling in her hands for 6 months. She reports a family history of rheumatoid arthritis (RA). Which of the following is NOT a risk factor for RA?

Choice A reason: Older age is not a primary risk factor for RA; the disease often begins between 30 and 60 years of age, and younger adults can be affected. Choice B reason: Obesity is associated with systemic inflammation and may increase susceptibility to autoimmune diseases, making it a contributing risk factor. Choice C reason: Family history is a recognized risk factor because RA has a genetic predisposition linked to HLA-DR alleles. Choice D reason: Current or prior cigarette smoking is a well-established environmental risk factor that can trigger autoimmune responses and increase RA risk.