Thrombophilia and vascular risk factors in retinal vein occlusion

Risk factors in developing retinal vein occlusion in subject with obstructive sleep apnea

BACKGROUND

Patients with obstructive sleep apnea (OSA) have a higher risk of developing vascular diseases. In this study, we evaluated the clinical profile of patients with OSA who develop retinal vein occlusion (RVO) compared with a population of OSA patients without RVO.

METHODS

We analyzed patients with OSA diagnosed with RVO (21 cases; mean of age 61 years. range 44-87 years. 67% men), belonging to a large cohort of people with long-term follow-up for RVO (up to 12 years). We compared them with 21 patients with OSA, without RVO, matched by age and gender, selected from the Sleep Unit Registry (control group).

RESULTS

There were no differences in the prevalence of arterial hypertension (AHT) or Diabetes mellitus (DM), but the RVO patients presented a higher diastolic blood pressure compared to controls (87.6±12.6 mmHg vs. 77.9±10.1 mmHg respectively). The polygraphic parameters were similar in both groups. The Apnea-Hypopnea Index (IHA) similar in both groups (30.4±20.9 RVO vs. 33.7±22.1 controls). In addition, RVO patients had a less favorable lipid profile, with higher total cholesterol (218±52 mg/dL vs. 179±41 mg/dL), higher LDL cholesterol (139±47 mg/dL vs. 107±32 mg/dL) and higher atherogenic indices: LDL/HDL (2.78±0.95 RVO vs. 2.03±0.67 controls) and total cholesterol/HDL (4.37±1.08 vs. 3.45±0.84). Among the cases, 81% had peripheral RVO (superior temporal branch in 20 out of 21 cases) and 19% had central RVO. A percentage of 62% of the cases received intravitreal antiangiogenic therapy and dexamethasone implants and 33% received argon laser photocoagulation.

CONCLUSIONS

Poor control of cardiovascular risk factors, particularly dyslipidemias, in patients with OSA may lead to the development of this ocular complication.

Platelet and Thrombophilia-Related Risk Factors of Retinal Vein Occlusion

Retinal vein occlusion (RVO) is a heterogenous disorder in which the formation of a thrombus results in the retinal venous system narrowing and obstructing venous return from the retinal circulation. The pathogenesis of RVO remains uncertain, but it is believed to be multifactorial and to depend on both local and systemic factors, which can be divided into vascular, platelet, and hypercoagulable factors. The vascular factors include dyslipidaemia, high blood pressure, and diabetes mellitus. Regarding the platelet factors, platelet function, mean platelet volume (MPV), platelet distribution width (PDW), and platelet large cell ratio (PLCR) play key roles in the diagnosis of retinal vein occlusion and should be monitored. Nevertheless, the role of a hypercoagulable state in retinal vein occlusion remains unclear and requires further studies. Therefore, the following article will present the risk factors of RVO associated with coagulation disorders, as well as the acquired and genetic risk factors of thrombophilia. According to Virchow’s triad, all factors mentioned above lead to thrombus formation, which causes pathophysiological changes inside venous vessels in the fundus of the eye, which in turn results in the vessel occlusion. Therefore, a diagnosis of retinal vein occlusion should be based on both eye examination and general examination, including laboratory tests.

Treatment of retinal vein thrombosis: what about anticoagulants?

Retinal vein occlusion is an important cause of vision loss. The current treatment options are mainly directed to the prevention of neovascular complications and few studies have addressed to potential use of anticoagulant agents and other interventions targeting the coagulation system. Herein we review the general aspects of this condition focusing on the potential benefits of anticoagulant treatment.