Serum Uric Acid as a Clinical Marker of Resistant and Uncontrolled Hypertension: A Cross-Sectional Study from a Tertiary-Care Center in Pakistan

Objectives: This study evaluated the association between serum uric acid (SUA) levels and blood pressure (BP) control status among hypertensive patients and explored its potential role as a marker of resistant and uncontrolled hypertension. Methodology: A cross-sectional analytical study was conducted in the Department of Cardiology at Mardan Medical Complex, Pakistan (May 2024–October 2025). Adults (≥18 years) with primary hypertension on stable therapy were enrolled. Participants were categorized as controlled, uncontrolled, or resistant hypertension according to guideline-based definitions. Group differences in SUA were assessed using the Kruskal–Wallis test with post-hoc Mann–Whitney U testing. Associations between SUA and biochemical parameters were evaluated using Spearman’s rank correlation. An exploratory decision-tree model examined data-driven SUA thresholds associated with BP control status. Results: Among 264 participants (mean age 59.8 ± 11.6 years; 57.2% male; BMI 28.5 ± 4.8 kg/m²), BP status was controlled in 18.6%, uncontrolled in 43.6%, and resistant in 37.9%. Mean SUA was 6.21 ± 1.41 mg/dL. SUA levels differed significantly across BP categories (H = 31.23, p < 0.001), with higher values observed in resistant and uncontrolled groups compared to controlled hypertension. Decision-tree analysis identified a primary SUA split at ~6.15 mg/dL, with levels >6.95 mg/dL predominantly associated with resistant hypertension. SUA correlated positively with creatinine (ρ = 0.17, p = 0.0278) and triglycerides (ρ = 0.26, p = 0.0265), and inversely with eGFR (ρ = −0.21, p = 0.0468). Conclusion: Elevated serum uric acid was significantly associated with poorer blood pressure control, particularly resistant hypertension. These findings suggest that SUA may serve as a descriptive clinical marker reflecting underlying metabolic and renal burden in difficult-to-control hypertension. Prospective studies are required to determine its predictive and therapeutic implications.