Complete Blood Count and Retinal Vessel Calibers

Abstract

ObjectiveThe influence of hematological indices such as complete blood count on microcirculation is poorly understood. Retinal microvasculature can be directly visualized and vessel calibers are associated with a range of ocular and systemic diseases. We examined the association of complete blood count with retinal vessel calibers.MethodsCross-sectional population-based Blue Mountains Eye Study, n = 3009, aged 49+ years. Complete blood count was measured from fasting blood samples taken at baseline examination, 1992–4. Retinal arteriolar and venular calibers were measured from digitized retinal photographs using a validated semi-automated computer program.ResultsAll analyses adjusted for age, sex, systolic blood pressure, diabetes, smoking and fellow vessel caliber. Higher hematocrit, white cell count and platelet count were associated with narrower arteriolar caliber (p = 0.02, 0.03 and 0.001 respectively), while higher hemoglobin, hematocrit, red cell count, white cell count and platelet count were associated with wider venular caliber (p<0.0001 for all). Each quintile increase in hematocrit, white cell count and platelet count was associated with approximately 0.5 µm narrower arteriolar caliber; whereas each quintile increase in all of the complete blood count components was associated with approximately 1–2 µm wider venular caliber.ConclusionsThese associations show that elevated levels of hematological indices can have adverse effects on the microcirculation.

Inflammation mediates the relationship between obesity and retinal vascular calibre in 11-12 year-olds children and mid-life adults

“…The Generation R Study of children aged 6 years found that each SD higher CRP was associated with 0.10 SD (95% CI 0.06 to 0.14) wider venular calibre 3 . Similar findings are reported in mid-life and older adults and with other inflammatory markers, such as fibrinogen and white blood cells count [23][24][25][26][27] . GlycA is a novel composite inflammatory marker with greater stability and lower intra-individual variability than single acute phase inflammatory proteins, such as hsCRP 28 .…”

“…The CheckPoint study was approved by the Royal Children's Hospital Melbourne Human Research Ethics Committee (33225D) and the Australian Institute of Family Studies Ethics Committee (14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26). The attending parents/caregivers provided written informed consent for themselves and their children to participate.…”

Subfoveal Choroidal Thickness Is Associated with Blood Hematocrit Level

“…On the other hand, the retinal venule caliber is significantly correlated with blood hematocrit levels, thus indicating that increase in blood viscosity widens retinal venules, rendering the retinal arterioles unchanged. Liew et al [11] reported that higher hematocrit levels are associated with narrower arterioles and wider venules. The mean RVC values in our study were lower compared to the data of some previously published research [17,18].…”

“…However, there are no comprehensive research studies in the literature about retina-choroidal vasculature in patients with PV. In a large population-based study, it was reported that a higher hematocrit level is associated with a narrower retinal arteriolar caliber and a wider retinal venular caliber [11]. …”

Peripapillary Retinal Nerve Fiber Layer Thickness in Patients with Polycythemia Vera

“…PV hastalarında retinal arterlerde daralma ve retinal venlerde genişleme sonucu retinal mikro dolaşımın etkilendiği gösterilmiştir. 4 İskemik optik nöropati, retinal hemoraji ve papilödem tablolarını içeren optik sinir tutulumları da bildirilmiştir. 5,6 PV hastalarında görülen oküler komplikasyonlar trombozise yatkınlık ve artmış kan viskozitesi nedeni ile ortaya çıkmaktadır.…”