Serum P-Cresyl Sulfate Levels Correlate with Peripheral Arterial Disease in Hypertensive Patients

Background/Objectives: p-Cresyl sulfate (PCS) is implicated in inflammation, oxidative stress and vascular dysfunction. Hypertension is a major risk factor for peripheral arterial disease (PAD), which is linked to increased mortality in patients with hypertension. This study aimed to evaluate the association between serum PCS levels and PAD in hypertension cases. Methods: We analyzed fasting blood samples and clinical data from 105 patients with hypertension in a cardiovascular outpatient clinic. Serum PCS levels were quantified using high-performance liquid chromatography–mass spectrometry. Ankle–brachial index (ABI) was measured using an automated oscillometric device; ABI < 0.9 indicated PAD. Results: A total of 24 patients (22.9%) had PAD. The PAD group had a higher prevalence of diabetes mellitus (p = 0.026), elevated serum C-reactive protein (CRP) levels (p < 0.001) and increased PCS levels (p = 0.002) than the normal ABI group. Multivariate logistic regression showed that PCS (odds ratio [OR]: 1.154, 95% confidence interval [CI]: 1.013–1.315, p = 0.031) and CRP (per 0.1 mg/dL increase, OR: 1.649, 95% CI: 1.138–2.389, p = 0.008) were independently associated with PAD. According to Spearman’s correlation analysis, log-transformed PCS (log-PCS) levels negatively correlated with left or right ABI (p = 0.001 and p = 0.004, respectively) and estimated glomerular filtration rate (p = 0.001) but positively correlated with log-CRP (p = 0.024). Conclusions: Elevated serum PCS and CRP levels are significantly associated with PAD in patients with hypertension, suggesting the potential role of PCS in PAD pathogenesis.