Autoimmune & Arthritis

Aging biology may explain why systemic sclerosis looks so different from patient to patient

Systemic sclerosis is a rare autoimmune disease that scars the skin, lungs, heart, and blood vessels, and it looks very different from one patient to the next. This review argues that biological aging, rather than calendar age alone, may help explain those differences. Hallmarks of aging such as chronic low-grade inflammation, senescent cells, and aging immune systems show up in the tissues the disease damages. Reported peaks in disease incidence overlap with two points in life, around ages 44 and 60, when the body undergoes major molecular shifts, though whether these shifts cause disease onset is unknown. Older-onset patients have more pulmonary hypertension and worse survival, while younger patients face their own risks, including strokes, heart failure, early bone loss, and early ovarian failure. The authors call for biologically meaningful age cut-offs in future trials.