Renin-Angiotensin System Inhibitor Usage and Age-Related Macular Degeneration among Hypertensive Patients: Results from the National Health and Nutrition Examination Survey, 2005-2008

Glaucoma and the ocular renin-angiotensin-aldosterone system: Update on molecular signalling and treatment perspectives

Glaucoma, a leading cause of blindness worldwide, encompasses a group of pathological conditions affecting the optic nerve and is characterized by progressive retinal ganglion cell loss, cupping of the optic nerve head, and distinct visual field defects. While elevated intraocular pressure (IOP) is the main risk factor for glaucoma, many patients do not have elevated IOP. Consequently, other risk factors, such as ocular blood flow abnormalities and immunological factors, have been implicated in its pathophysiology. Traditional therapeutic strategies primarily aim to reduce IOP, but there is growing interest in developing novel treatment approaches to improve disease management and reduce the high rates of severe visual impairment. In this context, targeting the ocular renin-angiotensin-aldosterone system (RAAS) has been found as a potential curative strategy. The RAAS contributes to glaucoma development through key effectors such as prorenin, angiotensin II, and aldosterone. Recent evidence has highlighted the potential of using RAAS modulators to combat glaucoma, yielding encouraging results. Our study aims to explore the molecular pathways linking the ocular RAAS and glaucoma, summarizing recent advances that elucidate the role of the RAAS in triggering oxidative stress, inflammation, and remodelling in the pathogenesis of glaucoma. Additionally, we will present emerging therapeutic approaches that utilize RAAS modulators and antioxidants to slow the progression of glaucoma.

Splenic monocytes drive pathogenic subretinal inflammation in age-related macular degeneration

Age-related macular degeneration (AMD) is invariably associated with the chronic accumulation of activated mononuclear phagocytes in the subretinal space. The mononuclear phagocytes are composed of microglial cells but also of monocyte-derived cells, which promote photoreceptor degeneration and choroidal neovascularization. Infiltrating blood monocytes can originate directly from bone marrow, but also from a splenic reservoir, where bone marrow monocytes develop into angiotensin II receptor (ATR1)+ splenic monocytes. The involvement of splenic monocytes in neurodegenerative diseases such as AMD is not well understood. Using acute inflammatory and well-phenotyped AMD models, we demonstrate that angiotensin II mobilizes ATR1+ splenic monocytes, which we show are defined by a transcriptional signature using single-cell RNA sequencing and differ functionally from bone marrow monocytes. Splenic monocytes participate in the chorio-retinal infiltration and their inhibition by ATR1 antagonist and splenectomy reduces the subretinal mononuclear phagocyte accumulation and pathological choroidal neovascularization formation. In aged AMD-risk ApoE2-expressing mice, a chronic AMD model, ATR1 antagonist and splenectomy also inhibit the chronic retinal inflammation and associated cone degeneration that characterizes these mice. Our observation of elevated levels of plasma angiotensin II in AMD patients, suggests that similar events take place in clinical disease and argue for the therapeutic potential of ATR1 antagonists to inhibit splenic monocytes for the treatment of blinding AMD.

Angiotensin-converting enzyme inhibitors and risk of age-related macular degeneration in individuals with hypertension

AIMS

Several observational studies have examined the potential protective effect of angiotensin-converting enzyme inhibitor (ACE-I) use on the risk of age-related macular degeneration (AMD) and have reported contradictory results owing to confounding and time-related biases. We aimed to assess the risk of AMD in a base cohort of patients aged 40 years and above with hypertension among new users of ACE-I compared to an active comparator cohort of new users of calcium channel blockers (CCB) using data obtained from IQVIA Medical Research Data, a primary care database in the UK.

METHODS

In this study, 53 832 and 43 106 new users of ACE-I and CCB were included between 1995 and 2019, respectively. In an on-treatment analysis, patients were followed up from the time of index drug initiation to the date of AMD diagnosis, loss to follow-up, discontinuation or switch to the comparator drug. A comprehensive range of covariates were used to estimate propensity scores to weight and match new users of ACE-I and CCB. Standardized mortality ratio weighted Cox proportional hazards model was used to estimate hazard ratios of developing AMD.

RESULTS

During a median follow-up of 2 years (interquartile range 1-5 years), the incidence rate of AMD was 2.4 (95% confidence interval 2.2-2.6) and 2.2 (2.0-2.4) per 1000 person-years among the weighted new users of ACE-I and CCB, respectively. There was no association of ACE-I use on the risk of AMD compared to CCB use in either the propensity score weighted or matched, on-treatment analysis (adjusted hazard ratio: 1.07 [95% confidence interval 0.90-1.27] and 0.87 [0.71-1.07], respectively).

CONCLUSION

We found no evidence that the use of ACE-I is associated with risk of AMD in patients with hypertension.

Associations between systemic medications and development of wet age-related macular degeneration

PURPOSE

To examine whether systemic medications are associated with the subsequent development of wet age-related macular degeneration (AMD).

METHODS

A retrospective study of 259 562 individuals based on registry data, from January 1, 2001, to December 31, 2017. End-point event was the International Classification of Diseases (ICD)-10 diagnosis for wet AMD. Association between use of systemic medication covering 85 generic drugs categorized according to Anatomical Therapeutic Chemical (ATC) codes and the incidence of wet AMD was evaluated using multivariate Poisson regression model (adjusted for age, sex, diabetes, cancer and socioeconomic group) and nested case-control design.

RESULTS

The mean length of follow-up was 9.84 years. The number of cases with wet AMD was 2947 and incidence rate was 1.15 per 1000 person-years. After adjustment, we observed an increased risk for the development of wet AMD for patients exposed to amlodipine (IRR 1.33, 95% CI 1.16-1.53), or felodipine (1.24, 95% CI 1.02-1.50). Similarly, an increased risk of wet AMD was associated with the use of bicalutamide (2.14, 95% CI 1.14-4.02), estradiol (1.20, 95% CI 1.03-1.40) and atorvastatin (1.22, 95% CI 1.05-1.43). Of note, digoxin (0.72, 95% CI 0.57-0.91), and ramipril (0.80, 95% CI 0.65-0.99) users had a lower incidence of wet AMD.

CONCLUSIONS

Our findings suggest that the use of second-generation calcium channel blockers could be associated with an increased risk for wet AMD development. Of note, the incidence of wet AMD seemed to be lower in patients using ramipril and digoxin. More studies are needed to elucidate the associations further.