Increased Lipoprotein-associated phospholipase A2 activity portends an increased risk of resistant hypertension.

Background: To investigate the relationship between plasma lipoprotein-associated phospholipase A2 (Lp-PLA2) activity and incidence of resistant hypertension (RH).

Methods: This was a cross-sectional research. In essential, it was an observational design and collecting data on a population at a single point in time to evaluate the associations of studied variables. Totally 208 patients with arterial hypertension were enrolled. Baseline characteristics were collected and fasting venous blood were drawn for plasma Lp-PLA2 activity assessment. Twenty-four hour ambulatory blood pressure ambulatory (ABPM) was performed to diagnose RH. Initially, based on ABPM examination, all participants were divided into two groups, namely RH group and without RH group. And thereafter, in order to evaluate the effects of Lp-PLA2 activity on blood pressure, all participants were divided into low (< 225 nm/min/ml) and high (≥ 225 nm/min/ml) Lp-PLA2 activity groups based on the cut-off value of Lp-PLA2 activity. Comparisons were conducted between groups.

Results: Forty two patients were diagnosed as RH. Compared to patients without RH, patients with RH were more elderly, had more males, smokers, longer duration of hypertension, higher plasma C-reactive protein (CRP) level and Lp-PLA2 activity (P < 0.05 for all comparisons). More RH patients treated with calcium channel blocker and diuretic, while less treated with angiotensin converting enzyme inhibitor, angiotensin receptor blocker and statins (P < 0.05 for all comparisons). Compared to low Lp-PLA2 group, the rate of RH was significantly higher in high Lp-PLA2 group (26.7 % versus 6.1 %, P < 0.05). Multivariate regression analysis revealed that after adjusted for age, gender, smoking, body mass index, hypertension duration, CRP, and anti-hypertensive drugs, association between Lp-PLA2 activity and RH remained significant, with odds ratio (OD) of 2.02 (95 % confidence interval, CI 1.85-2.06, P < 0.05). Nonetheless, the association was attenuated when further adjusted for statins, with OR of 1.81 (95 % CI 1.74-1.93, P < 0.05).

Conclusion: Increased plasma Lp-PLA2 activity portends increased risk of RH, and statins may be beneficial to reduce incidence of RH in subjects with increased plasma Lp-PLA2 activity.