Background: The prognostic value of on-treatment mean cumulative ambulatory blood pressures (BPs) in type 2 diabetes has never been investigated. We aimed to assess it in a prospective cohort of 647 individuals with type 2 diabetes.
Methods: Clinic-office and ambulatory BPs were measured at baseline and serially during follow-up. Multivariable Cox analyses assessed the associations between baseline and mean cumulative BPs with the occurrence of cardiovascular events, major adverse cardiovascular events, all-cause and cardiovascular mortality, and microvascular outcomes (microalbuminuria, renal failure, retinopathy, and peripheral neuropathy). C statistics and the integrated discrimination improvement (IDI) index evaluated the improvement in risk discrimination by using cumulative ambulatory BPs instead of baseline BPs.
Results: Over a median follow-up of 10.6 years, there were 202 cardiovascular events (163 major adverse cardiovascular events), 254 all-cause deaths (118 cardiovascular); 125 individuals had microalbuminuria development/progression, 104 developed advanced renal failure, 159 had retinopathy, and 174 individuals had peripheral neuropathy development/progression. The risks associated with mean cumulative ambulatory BPs were in general higher than those associated with baseline BPs, particularly for cardiovascular (HR, 1.42 versus 1.25 for increments of 1 SD in 24-hour systolic blood pressure) and mortality outcomes (1.56 versus 1.26). Compared with cumulative clinic BPs, mean cumulative ambulatory BPs improved risk discrimination for most outcomes, with IDIs from 11% to 14% for major adverse cardiovascular events and mortality up to 24% to 26% for microalbuminuria and neuropathy.
Conclusions: Compared with clinic-office BPs, mean cumulative ambulatory BPs during follow-up improve risk discrimination for most complications and mortality in individuals with type 2 diabetes. Serial ambulatory BP monitoring shall be more widely used in clinical management.
Keywords: ambulatory blood pressure; cardiovascular events; cohort study; microvascular complications; risk stratification.