Association of increased levels of plasma tumor necrosis factor alpha with primary open-angle glaucoma

Figures & data

Figure 1 Box plot showing the distribution of TNF-α levels in the POAG cases and control group.

Abbreviations: POAG, primary open-angle glaucoma; TNF-α, tumor necrosis factor alpha.

Table 1 Demographics, clinical characteristics and TNF-α level in POAG cases and controls

Variables	POAG (n = 51)	Controls (n = 88)	p-value
Age, mean (SD) (years)	59.0 (13.2)	57.1 (12.1)	0.409a
Gender (M/F)	29/22	53/35	0.697b
Diabetes mellitus, n (%)	22 (43.1)	28 (31.8)	0.287b
Hypertension, n (%)	20 (39.2)	28 (31.8)	0.377b
Hypercholesterolemia, n (%)	2 (3.9)	3 (3.4)	0.751b
Coronary artery disease, n (%)	1 (1.9)	2 (3.4)	0.628b
Smoking, n (%)	2 (3.9)	4 (4.5)	0.795b
TNF-α, mean (SD) (pg/mL)	1.88 (2.17)	0.93 (1.49)	0.003a

Notes:

a Independent sample t-test.

b Pearson’s chi-square test.

Abbreviations: F, female; M, male; POAG, primary open-angle glaucoma; TNF-α, tumor necrosis factor alpha.

Table 2 Quartile distribution of TNF-α level to assess the risk of POAG

TNF-α (pg/mL) by quartilesa	Cases (n = 51), n (%)	Controls (n = 88), n (%)	Odds ratio	95% confidence interval	p-value
0	18 (35.3)	51 (57.9)	Reference	–	–
0.1–2.3	13 (25.5)	21 (23.8)	1.75	0.73–4.21	0.206
>2.3	20 (39.2)	16 (18.1)	3.54	1.51–8.27	0.0028

Notes:

a First quartile: <25th percentile; interquartile: 25th–75th percentile; third quartile: >75th percentile. Overall dose–response trend was significant (χ² = 6.12, df = 2; p = 0.047).

Abbreviations: POAG, primary open-angle glaucoma; TNF-α, tumor necrosis factor alpha.

Table 3 Correlation between TNF-α level and other clinical variables

Variables	R	p-value
Age	0.124	0.155
Intraocular pressure	−0.197	0.179
Cup-to-disc ratio	−0.031	0.836
Number of antiglaucoma medications	−0.285	0.042

Note: R, Spearman’s correlation coefficient.

Abbreviation: TNF-α, tumor necrosis factor alpha.

Table 4 Binary logistic regression analysis to determine the effect of age, sex and TNF-α level on disease outcome

Variables	Odds ratio	95% confidence interval	p-value
Age	1.01	0.977–1.038	0.645
Sexa	0.997	0.467–2.126	0.993
TNF-α	1.35	1.100–1.650	0.004

Note:

a Female as reference.

Abbreviation: TNF-α, tumor necrosis factor alpha.