Association Between Familial Mediterranean Fever and P-Wave Dispersion Under Colchicine Treatment

Background/Objectives: The relationship between P-wave dispersion (Pd) and disease status in patients with Familial Mediterranean Fever (FMF) undergoing colchicine treatment is unclear in the literature, and results are contradictory. This study aimed to evaluate P-wave dispersion in patients with Familial Mediterranean Fever receiving regular long-term colchicine treatment and to compare these findings with those of age- and sex-matched individuals without FMF. Methods: A cross-sectional and observational study included 97 individuals with positive FMF and 97 individuals with negative FMF. FMF diagnosis was confirmed according to the Tel-HaShomer criteria, and all patients received regular colchicine treatment and were evaluated during the attack-free period. P maximum, P minimum, and Pd were measured using standard 12-lead electrocardiography (ECG); clinical, laboratory, and drug data were recorded. Pd associations were analyzed using correlation and multivariable regression. Results: Pd was found to be significantly higher in FMF (+) patients (47 vs. 39 ms, p < 0.001). Pd showed a positive correlation with FMF status (r = 0.508, p < 0.001), colchicine dose (r = 0.476, p < 0.001), white blood cell (WBC) (r = 0.209, p = 0.005) and high-density lipoprotein cholesterol (HDL-C) (r = 0.156, p = 0.037) and a negative correlation with calcium channel blocker use (r = −0.245, p = 0.001). In multivariate analysis, FMF increased Pd by 10.17 ms, while calcium channel blockers decreased it by 11.78 ms (p < 0.001). Age, WBC and HDL-C also had independent positive effects on Pd (p < 0.001, p = 0.017, p = 0.040, respectively). Conclusions: These findings suggest that FMF is associated with increased P-wave dispersion despite regular colchicine treatment, indicating persistent subclinical atrial conduction heterogeneity.