Carotid plaque instability is a risk factor for ischemic stroke, and changes in serum creatinine are associated with carotid plaque. However, the relationship between serum creatinine and carotid plaque stability is not well explained. This study aimed to interpret this relationship for clinical treatment of carotid plaque.
A total of 4363 subjects aged 29-86 from December 2013 to December 2018 were included in this study. The stability of carotid plaque was determined based on ultrasound echoes and divided into two groups: carotid plaque stable group and carotid plaque unstable group. The relationship between serum creatinine and carotid plaque stability was determined using curve fitting methods as well as logistic regression.
After age stratification, there was an inverted U-shaped curve between the stability of right carotid plaque and serum creatinine in males, When serum creatinine levels were less than 84 μmol/L, the probability of carotid plaque instability gradually increased, and the carotid plaque became stable when creatinine levels were greater than 84 μmol/L. The relationship between left carotid female plaque stability and serum creatinine showed a U-shaped curve. When serum creatinine levels were less than 80 μmol/L, the carotid plaque stability stabilized, and the probability increased when creatitine levels were more than 80 μmol/L, as the carotid plaque instability rose.
There was an inverted U-shaped relationship between the stability of carotid plaque in the right carotid artery and serum creatinine in males, and a U-shaped relationship between the stability of carotid plaque in the left carotid artery and serum creatinine in females.

Background: The possible effects of dietary fiber intake on hypertension have not been clarified fully. The association of dietary fiber intake with hypertension risk in midlife women was analyzed in this study. Methods: Baseline data were obtained from the Study of Women\'s Health Across the Nation (SWAN). Smooth curve, linear regression, and logistic regression analyses were performed to investigate the associations of four indices of daily dietary estimate (DDE) of dietary fiber (dietary fiber intake, dietary fiber intake from beans, dietary fiber intake from vegetables/fruit, and dietary fiber intake from grains) with blood pressure in midlife women. For this research purpose, diastolic blood pressure (DBP) ≥90 mmHg was defined as diastolic hypertension, and systolic blood pressure (SBP) ≥140 mmHg was defined as systolic hypertension. Results: This study included 2,519 participants with an average age of 46. The smooth curve showed approximate negative correlations between three fiber indices (DDE dietary fiber, DDE fiber from vegetables/fruit, and DDE fiber from grains) and blood pressure, including DBP and SBP (all P < 0.005). There were also approximate negative correlations between two fiber indices (DDE dietary fiber and DDE fiber from grains) and the risk of diastolic hypertension and systolic hypertension (all P < 0.05). Furthermore, multiple linear regression analysis suggested that DDE dietary fiber (Sβ = -0.057, 95% CI -0.194 - -0.012, P = 0.027), DDE fiber from vegetables/fruit (Sβ = -0.046, 95% CI -0.263 - -0.007, P = 0.039), and DDE fiber from grains (Sβ = -0.073, 95% CI -0.600 - -0.099, P = 0.006, Model 4) were still negatively correlated with DBP after adjusting for confounding factors. Only DDE fiber from grains was independently and negatively associated with SBP (Sβ = -0.060, 95% CI -0.846 - -0.093, P = 0.015) after these same confounding factors were adjusted for. Importantly, multiple logistic regression analysis suggested that only higher DDE fiber from grains was independently associated with a reduced risk of diastolic hypertension (OR = 0.848, 95% CI 0.770-0.934, P = 0.001, Model 4) and systolic hypertension (OR = 0.906, 95% CI 0.826-0.993, P = 0.034, Model 4) after the adjustments were made for confounding factors. Conclusions: We found that dietary fiber intake, especially DDE fiber from grains, contributes to a lower risk of systolic hypertension and diastolic hypertension in midlife women.