Association between Diastolic Blood Pressure and Diabetic Kidney Disease: Insights from a Cross-Sectional Study in Kenya

Diabetic kidney disease (DKD) is a major complication of type 2 diabetes (T2D) and a leading cause of end-stage renal disease. While systolic blood pressure (SBP) has been widely studied, the role of diastolic blood pressure (DBP) in the development of Diabetic kidney disease remains unclear. This study assessed the association between DBP and DKD incidence in patients with T2D, adjusting for confounders. We also examined DKD risk factors and evaluated the discriminative ability of SBP and DBP via area under the receiver operating characteristic curve (AUROC) analysis. This study provides insights into the association between DBP and DKD among patients with type 2 diabetes. This cross-sectional study was conducted at a public referral hospital in Kiambu County, Kenya, from October 2023 to February 2024. Adults (≥20 years) with T2D and at least one year of follow-up were enrolled. We analysed the association of DBP with DKD and compared blood pressure parameters between those with and without DKD. The results indicated that among the 326 adults with T2D, 31.6% had DKD. DBP and SBP were significantly greater in the DKD group (p<0.05). DBP ≥90 mmHg was associated with increased DKD incidence (54.2% vs. 26.6%, p<0.001) and severe albuminuria (p<0.001). Through analysis, a DBP ≥90 mmHg remained independently associated with DKD (AOR: 4.17, 95% CI: 1.49–11.59, p=0.006). SBP showed better DKD discrimination (AUROC: 0.646) than DBP did (AUROC: 0.582). The study concluded that elevated DBP was significantly associated with DKD, albuminuria, and CHD, although SBP had a stronger association. These findings highlight the importance of comprehensive blood pressure management in mitigating DKD risk.