Association between normal systolic blood pressure maintenance and the risk of coronary artery calcification progression in asymptomatic non-diabetic and diabetic adults: a retrospective cohort study using data from the Korea initiatives on coronary artery calcification registry.

OBJECTIVES: To assess the association of normal systolic blood pressure maintenance (SBPmaintain) with coronary artery calcification (CAC) progression in non-diabetic and diabetic subjects at low to intermediate cardiovascular risk. DESIGN: Retrospective cohort study with a mean follow-up of 3.3 years. SETTING: Data from the Korea Initiatives on Coronary Artery Calcification registry were analysed. PARTICIPANTS: 10 754 asymptomatic Korean adults (51.5±8.6 years; 84.5% male; 14.2% diabetes) were enrolled. Participants were divided into two groups: normal SBPmaintain (<120 mmHg) and ≥elevated SBPmaintain (≥120 mmHg) at the time of follow-up CAC scan. MAIN OUTCOME MEASURES: CAC progression was defined as a difference of ≥2.5 between the square roots (√) of the baseline and follow-up coronary artery calcium score (CACS) (Δ√transformed CACS). Annualised Δ√transformed CACS was defined as Δ√transformed CACS divided by the interscan period. RESULTS: Compared with non-diabetics, the incidence of CAC progression was higher in diabetics (28.4% vs 47.3%, p<0.001) during a mean follow-up of 3.3 years. Normal SBPmaintain was inversely associated with an annualised Δ√transformed CACS (β: -0.18, 95% CI: -0.25 to -0.12, p<0.001) in non-diabetics, but not in diabetics (β: -0.07, 95% CI: -0.31 to 0.19, p=0.631). After consecutive adjustments of age, sex, hypertension, dyslipidaemia, obesity, current smoking and baseline CACS, normal SBPmaintain showed a lower risk of CAC progression than ≥elevated SBPmaintain in non-diabetics; however, this association was not observed in patients with diabetes. CONCLUSIONS: Maintaining normal systolic blood pressure was associated with a significantly attenuated CAC progression, especially in clinical conditions without established diabetes.