Retinal vascular changes and immune restoration in a cohort of HIV patients on highly active antiretroviral therapy

Abstract

 

Purpose

 

To investigate whether retinal microvascular changes are predictive of subsequent CD4 /CD8 and hemoglobin (Hb) levels in HIV patients on highly active antiretroviral therapy (HAART)

 

Methods

 

Prospective,longitudinal study.100 HIV/AIDS patients on HAART were followed up over 9 months. Patient demographics, history of HIV infection, serologic tests for immune status assessment (CD4/CD8 cell counts, Hb, HIV viral load) and retinal photography were collected at quarterly intervals. A semi-automated computer-based programme was used to assess retinal vascular parameters of caliber, tortuosity, branching angle (Ba), and fractal dimension (Df). Linear mixed model analysis was used to detect associations of baseline retinal vascular caliber and immune restoration after adjusting for age, gender, race and co-morbidities.

 

Results

 

Majority of the patients were Chinese (80%) and males (95%). Mean age was 45 years. (Range 26-74) There were significant increments in CD4 cell counts (97 vs 187; p<0.001) and CD8 cell counts (681 vs 933; p<0.001) between baseline and 3-months respectively. Linear mixed model analysis showed that each 1 μm reduction in retinal arteriolar caliber was significantly associated with a subsequent 2.65 cells/µl decrease in CD4 count (p=0.021) and a 0.03 g/dl decrease in Hb level (p=0.014). Each 1° increase in arteriolar Ba was also significantly associated with a subsequent 3.74 cells/ul decrease in CD4 count (p=0.001) and T helper cell (Thc ) levels (0.14, p=0.003). A decrease in 0.1 unit of Df was also significantly associated with a subsequent 0.67 g/dl decrease in Hb level. (p=0.028)

 

Conclusions

 

Baseline retinal arteriolar caliber, arteriolar Df and arteriolar Ba are significantly associated with subsequent changes of CD4/ Thc/Hb. This may help clinicians better predict patients’ subsequent response to HAART and immune recovery based on patients’ pretreatment/ early treatment retinal microvasculature.

 

 

Table 2. Longitudinal association of baseline retinal vascular caliber and immune restoration in HIV/AIDS by using mixed model. Multivariate analysis: adjusted for age, gender, race, history of diabetes, history of cardiovascular attack, history of ischemic heart disease and history of hypertension.

 

Keywords: 415 AIDS/HIV • 688 retina • 550 imaging/image analysis: clinical