Association between serum alkaline phosphatase and C-reactive protein in the United States National Health and Nutrition Examination Survey 2005-2006.
BACKGROUND
Alkaline phosphatase (ALP) is a widely used marker for skeletal and hepatobiliary disorders, but its activity is also increased in atherosclerosis and peripheral vascular disease. It is an inflammatory marker like C-reactive protein (CRP). We therefore analyzed its relationship with CRP in the United States National Health and Nutrition Examination Survey (NHANES) 2005-2006.


METHODS
The analysis included 4155 men and non-pregnant women over the age of 20 years. The relationship between log-transformed ALP and plasma CRP was analyzed using univariate and multivariate models.


RESULTS
ALP activity was significantly correlated with age, waist circumference, body mass index, blood pressure, exercise, alcohol, triglycerides, and other liver enzymes after adjusting for age, gender and ethnicity (p<0.001). ALP was significantly associated with a higher frequency of cardiovascular disease (p=0.02), hypertension (p=0.01) hypercholesterolemia (p=0.04), and diabetes (p=0.02). Compared to the lowest quartile of ALP, the adjusted odds ratio (OR) associated with the highest quartile were 1.9 [95% confidence intervals (CI) 1.1-3.5], 1.6 (95% CI 1.0-2.5), 1.5 (95% CI 1.1-2.1) and 1.7 (95% CI 1.0-2.4) for cardiovascular disease, hypertension, hypercholesterolemia, and diabetes, respectively. In multivariate analysis, log ALP was an independent predictor of log CRP (p=1.0x10(-6)). A multivariate model that included log ALP, ethnicity, glycohemoglobin, waist circumference, albumin, apolipoprotein B, gamma-glutamyltransferase and uric acid explained 40% of the variance in log CRP.


CONCLUSIONS
ALP is a marker of cardiometabolic risk, but it needs to be tested as part of a multivariate model in prospective studies.
Webber
Matthew
M
School of Clinical and Experimental Medicine, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK.
Krishnan
Aisling
A
Thomas
Neil G
NG
Cheung
Bernard M Y
BM
D000367:Age Factors; D000469:Alkaline Phosphatase / Q000097:blood*; D001794:Blood Pressure; D001837:Body Weights and Measures; D002097:C-Reactive Protein / Q000378:metabolism*; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000208:ethnology / Q000378:metabolism; D003920:Diabetes Mellitus / Q000453:epidemiology / Q000208:ethnology / Q000378:metabolism; D005260:Female; D006306:Health Surveys; D006801:Humans; D006937:Hypercholesterolemia / Q000453:epidemiology / Q000208:ethnology / Q000378:metabolism; D006973:Hypertension / Q000453:epidemiology; D008055:Lipids / Q000097:blood; D008099:Liver / Q000201:enzymology; D008297:Male; D015999:Multivariate Analysis; D009749:Nutrition Surveys; D011446:Prospective Studies; D012307:Risk Factors; D012737:Sex Factors; D014481:United States / Q000453:epidemiology
D008055:Lipids; D002097:C-Reactive Protein; D000469:Alkaline Phosphatase