Background The optimal blood pressure (BP) level for diabetic patients remains controversial, and population-based evidence on BP management for individuals with normoglycemia and prediabetes is insufficient. We aimed to investigate the associations between systolic blood pressure (SBP) and all-cause mortality among US adults with different glucose metabolism.
Methods We used data from the 1999–2014 National Health and Nutrition Examination Survey (NHANES, n = 40,046) with comprehensive baseline examination and follow-up assessment. Restricted cubic spline was performed to examine dose-response relationship between continuous SBP and all-cause mortality. Cox regression models were used to estimate hazard ratios of all-cause mortality for SBP categories.
Results Over 32,5450 person-years of follow-up (median 8.1 years), 4745 all-cause death (11.8%) were recorded, corresponding to an event rate of 14.58 per 1000 patient years. U-shaped associations between SBP and all-cause mortality were observed regardless of glucose status. The lowest mortality risk of optimal SBP (mmHg) by group was 115–120 (normoglycemia), 120–130 (prediabetes), and 125–135 (diabetes). Compared with the reference group, SBP < 100 mmHg was significantly associated with 49% (HR = 1.49, 95%CI: 1.13–1.96), 57% (1.57, 1.07–2.3), and 59% (1.59, 1.12–2.25) higher mortality risk in normoglycemia, prediabetes, and diabetes, respectively. The multivariable-adjusted HRs of all-cause mortality for SBP of 150–159 mmHg and ≥ 160 mmHg were 1.35 (1.08–1.70) and 1.61 (1.31–1.98), 1.44 (1.13–1.83) and 1.66 (1.33–2.08), and 1.29 (1.02–1.65) and 1.37 (1.09–1.72), respectively.
Conclusions U-shaped relationships between SBP and all-cause mortality existed regardless of diabetes status. The optimal SBP range for the lowest mortality was gradually higher with worsening glucose status.