Alkaline phosphatase and prognosis in patients with diabetes mellitus and ischemic heart disease.

ABSTRACT

BACKGROUND: The association between alkaline phosphatase (ALP) and mortality in patients with diabetes mellitus (DM) and ischemic heart disease (IHD) remains poorly investigated. METHODS: The study included 1426 patients with DM and IHD who underwent percutaneous coronary intervention. Patients were divided in groups according to tertiles of ALP activity a group with ALP activity in 1st tertile (ALP activity 20.8-65.0 U/L; n = 478), a group with ALP activity in 2nd tertile (ALP activity 65.1-87.0 U/L; n = 473) and a group with ALP activity in 3rd tertile (ALP activity 87.1-1520 U/L; n = 475). The primary endpoint was 3-year all-cause mortality. RESULTS: At 3 years, all-cause deaths occurred in 182 patients 50 deaths (12.4%) in patients of 1st tertile, 47 deaths (11.7%) in patients of 2nd tertile and 85 deaths (20.8%) in patients of 3rd tertile of ALP activity (adjusted hazard ratio [HR] = 1.20, 95% confidence interval [CI] 1.02 to 1.42, P = 0.031); cardiac deaths occurred in 110 patients 28 deaths (7.0%) in patients of 1st tertile, 30 deaths (7.6%) in patients of 2nd tertile and 52 deaths (12.7%) in patients of 3rd tertile of ALP activity (adjusted HR = 1.27 [1.04-1.56], P = 0.021, with both risk estimates calculated for unit increment in the log scale of ALP activity). The C-statistic of the multivariable model with baseline data without and with ALP was 0.787 [0.750-0.818] and 0.804 [0.757-0.851], (P = 0.575) for all-cause mortality and 0.832 [0.798-0.864] and 0.876 [0.833-0.918], (P = 0.115) for cardiac mortality. CONCLUSIONS: In patients with DM and IHD, elevated ALP activity was associated with increased risk of 3-year mortality.