Emerging evidence supports a causal role for the immunoglobulin-M (IgM) as a protector of atherosclerosis. Since arterial stiffness is an index of subclinical atherosclerosis, we propose that IgM may play an important role in arterial stiffness. As the level of IgM differs between sexes, we investigate the sex-specific association of serum IgM with arterial stiffness in a Chinese population. The study subjects were recruited from Danyang in 2017. Using the Omron VP-1000 system, we measured brachial ankle pulse wave velocity (baPWV). Serum IgM concentration was measured by the immunoturbidimetry method. The 1030 study participants (mean age = 54.3 ± 9.0 years) included 407 men (39.5%), 428 hypertensive (41.6%), 80 diabetic (7.8%), and 512 arterial stiffness patients (49.7%). Serum IgM concentration was lower in men than women (0.97 vs. 1.26 μg/mL, P < 0.001) and negatively with alcohol intake (r = -0.11 in men and r = -0.07 in women, P ≤ 0.09). In multiple regression analyses, serum IgM concentration was negatively associated with baPWV in women (-0.82 m/s per 10-time increase in serum IgM concentration, P = 0.009) but not in men. In multivariable logistic regression analyses, elevated serum IgM concentration was associated with lower risks for arterial stiffness in women (OR = 0.26; 95% CI 0.08-0.82; P = 0.02) but not in men (OR = 0.66; 95% CI 0.17-2.62; P = 0.55). Categorical analyses produced similar results. Serum IgM is negatively associated with baPWV and accordingly associated with a lower risk of arterial stiffness in women.
Keywords: Arterial stiffness; Brachial ankle pulse wave velocity; Immunoglobulin-M.