Platelet distribution width is a predictive marker for development of severe retinopathy of prematurity

Association of platelet deficiency with severe retinopathy of prematurity: a review

“…In the present review, studies that defined subjects with stage 2 ROP or less as cases were explicitly excluded, to avoid confusion when interpreting the results (Figure 1). However, the definition of cases still differed significantly among studies, including type I ROP, 15,18,20,22,24,27,28,33 AP-ROP, 19 or ROP requiring treatment, encompassing both type I and AP-ROP, 16,21,23,26,[29][30][31] or at least stage 3 ROP. 25,31,32 Likewise, the definition of controls differed largely, including infants without ROP, 24,25,[27][28][29][30]32,33 ROP up to stage 1, 15,18,20,22,23 ROP up to stage 2, 19,31 or infants with less severe ROP, presumably including up to stage 3 without plus disease, namely type II ROP, 16,26 or even infants with unspecified ROP stage.…”

“…However, the definition of cases still differed significantly among studies, including type I ROP, 15,18,20,22,24,27,28,33 AP-ROP, 19 or ROP requiring treatment, encompassing both type I and AP-ROP, 16,21,23,26,[29][30][31] or at least stage 3 ROP. 25,31,32 Likewise, the definition of controls differed largely, including infants without ROP, 24,25,[27][28][29][30]32,33 ROP up to stage 1, 15,18,20,22,23 ROP up to stage 2, 19,31 or infants with less severe ROP, presumably including up to stage 3 without plus disease, namely type II ROP, 16,26 or even infants with unspecified ROP stage. 21 All these variations may affect the difference in the severity of ROP between the studied groups and therefore may have an impact on the outcome of interest.…”

“…Ultimately, 19 primary studies fulfilled the eligibility criteria and were included in this review: 18 clinical studies and one study with both experimental and clinical sections. All the clinical studies were observational, of which one case series, 17 eight retrospective case-control studies with or without matching, 15,[18][19][20][21][22][23][24] eight retrospective cohort studies, 16,[25][26][27][28][29][30][31] and two prospective cohort studies. 32,33 If studies comprised three groups, 24,27,29,30,33 comparative data were only collected on cases with ROP requiring treatment and the group of infants without ROP.…”

“…Over the last decade, a number of primary, observational, cohort or case-control studies, were conducted to evaluate associations between platelet parameters and severe ROP. 15,16,[18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33]…”

Comparison of Mean Platelet Counts in Preterm Infants with and without Retinopathy of Prematurity

“…Identifying risk factors for ROP may enhance the efficacy of screening programs. Various studies have attempted to clarify the relationship between platelet counts and ROP [ 12 , 13 , 14 , 15 , 16 , 19 , 20 , 21 , 22 , 23 ] ( Table 5 ). To our best knowledge, this is the first study to document that adjusted weekly mean platelet counts over the first 6 weeks of life have no direct relationship with ROP.…”