Diabetes, BP predict cardiovascular events, but not synergistically
MedWire News: The presence of diabetes and elevated 24-hour ambulatory blood pressure (24-hour BP) are both independently associated with increased risk for cardiovascular disease (CVD)-related events, but there is no evidence for a synergistic interaction between the two risk factors, suggest study results.
Diabetes and hypertension are known risk factors for CVD, but it is less clear "whether they act synergistically and potentiate one another," say Jan Staessen (University of Leuven, Belgium) and colleagues.
They assessed the contribution of diabetes status and 24-hour BP level to CVD risk in 8494 individuals, with a mean age of 54.6 years, from 10 countries. Of these, 6.9% were diabetic.
Over a median follow-up period of 10.6 years, 1066 participants had a CVD-related event (stroke, coronary heart disease, myocardial infarction, revascularization, or sudden cardiac death). The team found that diabetes and elevated 24-hour BP both independently and significantly predicted CVD-related events.
More specifically, following adjustment for 24-hour BP and other risk factors, presence of diabetes increased the risk for the composite outcome by 43-51%, depending on the model used.
Similarly, elevated systolic and diastolic BP (per standard deviation increase, ie, 14.27/8.46 mmHg) increased risk for CVD-related events by 38% and 31%, respectively, following adjustment for diabetes and other risk factors.
No evidence of synergism was observed between the two factors , the only exception being a borderline synergistic effect between diabetes and daytime diastolic BP in relation to the CVD endpoint.
"We could not confirm the commonly held assumption that the risks of diabetes mellitus and BP are synergistic and not merely additive," write Staessen et al in the journal Hypertension Research.
"This suggests that the same operational thresholds for the ambulatory BP might be applicable in diabetic patients and nondiabetic subjects," they say.
"Nonetheless, because of the higher absolute risk among diabetic patients, awareness, treatment and control of hypertension in diabetic patients will translate into a larger absolute reduction of cardiovascular morbidity and mortality than in non-diabetic subjects," concludes the team.
MedWire (www.medwire-news.md) is an independent clinical news service provided by Current Medicine Group, a trading division of Springer Healthcare Limited. © Springer Healthcare Ltd; 2011
By Helen Albert