Leuko-platelet index predicts thrombotic events in patients with acute coronary syndrome.

Purpose: To evaluate the predictive value of a bedside index in hospitalized patients with acute coronary syndromes (ACS).

Methods: We studied the association of leuko-platelet index (LPI: platelet count * leukocyte count/10) with risk of mortality, shock, or heart failure (combined end point-CEP), and with the response to antiplatelet therapy, measured by light transmission aggregometry.

Results: In the derivation cohort we included 1100 patients with non STEM-ACS, GRACE score of 133 ± 52, Crusade score 24,3 ± 14, 66% male, 65 + 11 years. LPI was 17 (12-24). LPI was higher (19 (13-25)) in patients with MI than in patients with unstable angina (16 (12-22) in (p < 0.001)). A total of 115 patients (10.5%) had the CEP. CEP was associated to LPI (OR 1.04 (1.002-1.08), p = 0.03), age (OR 1.01 (0.97-1.05), p = 0.62) and GRACE>140 (OR 8.1 (2.2-29), p = 0.02). LPI (OR 1.04 (1.004-1.07) p = 0.03) and GRACE score (OR 1.02 (1.01-1.03) p < 0.01) were associated to cardiovascular mortality. We confirmed these results in the validation cohort #1 (686 patients, 61 + 11 years old, 47% nonST-ACS, 53% ST-ACS, 21% had CEP) and in validation cohort #2 (218 patients, 56.8% males, 73 + 7 years old, 79% nonST-ACS, GRACE score 136 + 30) and 8.3% with CEP. We used the cutoff points of LPI obtained in the derivation cohort (>24).

Conclusions: LPI > 24 was associated to CEP (OR (1.7-5.2), p 0.01), independently of age (OR 1 (0.98-1.02), p = 0.8), and GRACE score (OR 1.01 (0.99-1.01), p 0.69), and It was associated to antiplatelet resistance (OR 1.03 (95% CI 1.00-1.06) p = 0.05).