BackgroundIt is known that there is a definite association between platelet distribution width (PDW) and poor prognosis in patients with coronary artery disease (CAD) and type 2 diabetes mellitus (T2DM). However, there are no data available regarding the prognostic significance of PDW for in-stent restenosis (ISR) in patients with CAD and T2DM. We aimed to determine the value of PDW on admission that predicted ISR in patients with CAD and T2DM.

MethodsBetween January 2012 and December 2013, a total of 5232 consecutive patients diagnosed with CAD and T2DM undergoing percutaneous coronary intervention were admitted. Three years of retrospective follow-up was undertaken. A total of 438 patients with second angiography operations were included. ISR was defined as ≥50% luminal stenosis of the stent or peri-stent segments. Continuous data were presented as the mean ± standard deviation or median (P, P) and were compared by one-way analysis of variance or Kruskal-Wallis H-test. Categorical variables were presented as percentages and were compared by Chi-square test or Fisher's exact test. The association between PDW and ISR was calculated by logistic regression analysis. A two-sided value of P < 0.05 was considered statistically significant. Statistical analyses were performed by SPSS version 22.0 for windows.

ResultsFifty-nine patients with ISR, accounting for 13.5% of the total, were included. ISR was significantly more frequent in patients with higher PDW quartiles compared with lower quartiles. We observed that PDW had a strong relationship with mean platelet volume (r = 0.647, 95% confidence interval [CI]: 0.535-0.750, P < 0.0001). The receiver-operating characteristic curves showed that the PDW cutoff value for predicting ISR rate was 13.65 fl with sensitivity of 59.3% and specificity of 72.4% (area under curve [AUC] = 0.701, 95% CI: 0.625-0.777, P < 0.001). Multivariate analysis showed that the risk of ISR increased approximately 30% when PDW increased one unit (odds ratio [OR]: 1.289, 95% CI: 1.110-1.498, P = 0.001). Patients with higher PDW, defined as more than 13.65 fl, had a 4-fold higher risk of ISR compared with lower PDW (OR: 4.241, 95% CI: 1.879-9.572, P = 0.001). Furthermore, when patients were divided by PDW quartiles values, PDW was able to predict ISR (Q2: OR = 0.762, 95% CI: 0.189-3.062, P = 0.762; Q3: OR = 2.782, 95% CI: 0.865-8.954, P = 0.086; and Q4: OR = 3.849, 95% CI: 1.225-12.097, P = 0.021, respectively; P for trend <0.0001).

ConclusionPDW is an independent predictor of ISR in patients with CAD and T2DM.