Arterial Hypertension and Kidney Function Decline in Systemic Sclerosis and Sjögren's Disease: A Longitudinal Comparative Study.

Abstract

Introduction: Renal involvement is increasingly recognized in Systemic Sclerosis (SSc) and Sjögren's Disease (SjD). However, the association between hypertension and renal function decline in these conditions remains poorly understood.

Aim: to compare renal function changes over time in patients with SSc and SjD; identify factors associated with clinically relevant renal function decline; and to evaluate whether the association between hypertension and renal function differs between the two diseases.

Methods: We retrospectively analyzed patients with SSc and SjD, followed for up to 3 years. Renal function was assessed using estimated glomerular filtration rate (eGFR). Clinically relevant renal decline was defined as a reduction in eGFR ≥10 ml/min Multivariable logistic regression identified factors associated with renal function decline, including the interaction between diagnosis and hypertension.

Results: A total of 238 patients were included (114 with SSc and 124 with SjD), with a median age of 55 years (IQR 45-65) in SSc and 57 years (IQR 48-66) in SjD. At baseline, SSc patients showed higher eGFR compared to SjD, but experienced a greater decline over time (median -6 vs -2.1 ml/min, p < 0.05). Overall, 33.8% of patients developed clinically significant renal decline. In multivariable analysis, hypertension was independently associated with renal function decline (OR 10.01, 95% CI 3.51-28.56, p < 0.001), whereas diagnosis was not. A significant interaction between diagnosis and hypertension was observed (OR 6.56, 95% CI 1.03-41.69, p = 0.046), indicating a stronger association between hypertension and renal function decline in SSc than in SjD. In subgroup analyses, hypertension was significantly associated with renal decline in SSc but not in SjD.

Conclusions: Hypertension was independently associated with renal function decline, with a stronger association in SSc than in SjD. These findings warrant confirmation in prospective studies. Systemic Sclerosis, Sjögren's disease, Estimated Glomerular Filtration Rate; arterial hypertension.