Effectiveness of Elevated Intraocular Pressure as a Criterion for Glaucoma Referral After 6 Years of Follow-Up

Figures & data

Figure 1 Flow chart showing the referral of patients eligible for inclusion in the study. The IOP-plus group includes referrals where other examinations, apart from IOP, had been conducted. Certain diagnosis denotes patients with a positive outcome before being lost to follow-up or those who died during follow-up. No ocular disease after follow-up indicates that patients were discharged from the hospital during the follow-up period because no further monitoring was necessary. Boxes with dashed lines indicate patients with an uncertain outcome due to lost to follow-up.

Abbreviation: IOP, intraocular pressure.

Table 1 Baseline Characteristics of All Referrals, IOP-Only and IOP-Plus Referrals

	All Referrals n=94	IOP-Only n=79	IOP-Plus n=15	p-value
Age in years, median (range)	62 (21–90)	61 (21–89)	66 (42–90)	0.466*
Gender, n (%)
Female	48 (51)	39 (49)	9 (60)	0.576**
IOP in mmHg measured at optometric practice, median (range)	28 (22–47)	28 (22–47)	28 (22–40)	0.338*
IOP - intraocular pressure,

Notes: *Mann–Whitney U-test, 2-tailed. **Fisher’s exact test, 2-sided.

Table 2 Outcome and Diagnoses at First Hospital Visit and Last Visit After Follow-Up for All Referrals, IOP-Only and IOP-Plus Referrals

	All Referrals n=94	IOP-Only n=79	IOP-Plus n=15	p-value*
Positive outcome, first visit	34 (36)	26 (33)	8 (53)	0.151
Positive outcome, after follow-up	44 (46)	33 (42)	11 (73)	0.046
Diagnosis first hospital visit
No ocular disease	29 (31)	28 (35)°	1 (7)	0.032
Glaucoma	21 (22)	14 (18)	7 (47)	0.037
PEXG	8 (38)	7 (50)	1 (14)
POAG	13 (62)	7 (50)	6 (86)
Suspected glaucoma	25 (27)	21 (27)	4 (27)	1.000
Treated	8 (32)	7 (33)	1 (25)
Not treated	18 (68)	14 (67)	3 (75)
Ocular hypertension	19 (20)	16 (20)	3 (20)	1.000
Treated	5 (26)	5 (31)	0 (0)
Not treated	14 (74)	11 (69)	3 (100)
Diagnosis after follow-up
No ocular disease^a	9 (10)	8 (10)	1 (7)	1.000
Glaucoma	30 (32)	22 (28)	8 (53)	0.071
PEXG	14 (47)	13 (59)	1 (12.5)
POAG	16 (53)	9 (41)	7 (87.5)
Suspected glaucoma	11 (12)	10 (13)	1 (7)	1.000
Treated	9 (82)	8 (80)	1 (100)
Not treated	2 (18)	2 (20)	0 (0)
Ocular hypertension	8 (9)	5 (6)	3 (20)	0.113
Treated	5 (62.5)	3 (60)	2 (67)
Not treated	3 (37.5)	2 (40)	1 (33)
Uncertain outcome	9 (10)	8 (10)	1 (7)	1.000

Notes: Results are shown as n (%). Positive outcome was defined as either definite glaucoma, treated glaucoma suspect or treated ocular hypertension. ^aPatients with normal exams during follow-up and no need for further monitoring were discharged. *Fisher’s exact test, 2-tailed. °Two patients who were found not to have any ocular disease at the first hospital visit were referred to the hospital again later; one was diagnosed with glaucoma and the other with suspected glaucoma and IOP-lowering treatment was started. Boldface indicates statistically significant P value (P < 0.05).

Abbreviations: IOP, intraocular pressure; POAG, primary open-angle glaucoma; PEXG, exfoliation glaucoma.

Figure 2 Outcome in the IOP-only group. The IOP-only group comprises patients were the referral was based solely on an elevated IOP. The thresholds investigated: ≥45 years of age at referral, IOP ≥25 mmHg and IOP ≥27 mmHg are indicated by the dashed lines.

Abbreviation: IOP, intraocular pressure.