Changes in Quality of Life Among Glaucoma Patients Following Six Months of Niacinamide Supplementation

Abstract

Background/Objectives: Glaucoma is the primary cause of irreversible blindness worldwide, with enormous impact on quality of life and activities of daily living. Since one pathogenic mechanism of glaucoma is mitochondrial dysfunction at the retinal ganglion cell level, niacin has been proposed as an adjuvant treatment, with encouraging results. The objective of this prospective, non-randomized, single-arm clinical trial was to investigate the effect of oral supplementation with niacin on the quality of life of a cohort of glaucoma patients in Romania. Methods: Fifty-eight patients diagnosed with primary open angle glaucoma, under topical hypotensive treatment, were evaluated before and after a 6-month period of daily administration of 500 mg of oral niacinamide. Evaluation involved a complete ophthalmological exam and QoL quantification using the Glaucoma Quality of Life-15 (GQL-15) Questionnaire. Results: We found strong evidence that niacin supplementation for 6 months led to a statistically significant improvement in QoL scores among glaucoma patients (mean difference = -2.10, 95% CI: [-2.89, -1.32], p < 0.0001), including central and near vision (mean difference = -2.16, 95% CI: [-3.91, -0.4], p = 0.017), peripheral vision (mean difference = -2.66, 95% CI: [-0.23, -0.08], p < 0.001), and the glare and dark adaptation (mean difference = -5.24, 95% CI: [-0.33, -0.14], p < 0.001). In addition, B3 treatment resulted in a significant reduction in intraocular pressure in both eyes over 6 months (mean difference = 0.53, 95% CI: [0.21, 0.86] in the left eye and mean difference = 0.36, 95% CI: [0.04, 0.68] in the right eye), indicating potential clinical benefits. Conclusions: The observed GQL-15 score reductions suggest that B3 may be of benefit in glaucoma management. Further research with larger sample sizes and placebo-controlled designs is needed to confirm B3 potential impact on disease progression and quality of life. Trial Registration at clinicaltrials.gov: NCT07007260.

Keywords: glaucoma; niacin; niacinamide; quality of life; vitamin B3.

Figure 1

Flow diagram of the inclusion process of the patients in the cohort study.

Figure 2

Change in score of QoL using GQL-15 (Glaucoma Quality of Life-15), where higher scores indicate worse QoL. Paired data (blue open circles) for each participant before (T0) and after treatment (T6). The black solid triangle represents the mean of the red open triangles (the difference in the score of QoL for every patient).

Figure 3

Change in score of central and near vision (CNV) using GQL-15.

Figure 4

Change in score of peripheral vision (PV) using GQL-15.

Figure 5

Change in score of glare and dark adaptation (GDA) using GQL-15.

Figure 6

Change in score of outdoor mobility (OM) using GQL-15.

Figure 7

The distribution of change in QoL scores (difference between baseline and post-treatment) across four glaucoma severity stages (1: Early stage, 2: Moderate, 3: Advanced, 4: Severe). A Kruskal–Wallis test was conducted to assess whether the degree of improvement differed significantly among the stages.

Figure 8

The heatmap illustrates the correlations between the changes in intraocular pressure (Right_IOP_diff for right eye and Left_IOP_diff for left eye) and the different clinical variables and quality of life indicators. Each cell in the heatmap represents the strength of correlation (rho value), with colors ranging from green (negative correlation) through white (no correlation) to blue (positive correlation). Stronger correlations are depicted with more intense coloration. IOP_diff, intraocular pressure difference; NoMolecules, number of INNs (International Nonproprietary Names).

Figure 9

Effect of niacinamide supplementation on eye intraocular pressure over 6 months. (A) Left eye. (B) Right eye. *, p < 0.05; **, p < 0.01.