Serum alkaline phosphatase (ALP) has been shown to be associated with cardiovascular disease (CVD) risk. Inflammation is the initiator of atherosclerosis, throughout the life of atherosclerosis. This study investigated the relationship between serum ALP and atherosclerosis in patients with coronary artery disease (CAD) in an inflammatory state.

This was a multicentre retrospective study including 22,989 patients with CAD. Serum alkaline phosphatase was converted into the quartiles. C-reactive protein (CRP) was assayed as a marker of systemic inflammation. The atherosclerosis index (AI) was used to assess the degree of atherosclerosis. Binary logistic regression was used to analyse the relationship between ALP and AI. Stratified analysis was performed according to sex and age.

Elevated serum ALP was associated with the risk of atherosclerosis in patients with CAD, and after quartiling ALP, the OR for Q4 was 1.17 (95% CI 1.08–1.26; p<0.001) when using Q1 as reference. The odds ratio (OR) for ALP and risk of atherosclerosis was higher in patients aged ≤60 years (OR 1.33, 95% CI 1.15–1.53; p<0.001) than in patients aged >60 years (OR 1.11, 95% CI 1.01–1.23; p<0.05), and higher in males (OR 1.21, 95% CI 1.09–1.35; p<0.001) than in females (OR 1.16, 95% CI 1.03–1.31; p<0.05). Q4 (ALP >83.00 U/L) was significantly associated with increased risk of atherosclerosis in the inflammatory state (OR 1.48, 95% CI 1.18–1.86; p<0.001), and it remained after stratified analysis according to sex and age.

The risk of atherosclerosis tended to increase with increasing ALP levels and the correlation between ALP and the degree of atherosclerosis was significantly stronger when ALP was >83.00 U/L. This relationship was more pronounced in inflammatory states, and there were sex and age differences.

URL: www.clinicaltrials.gov/; Unique identifier: NCT04026724