Glaucoma in United States Veterans: An Overlooked Group?

Priyanka Kamath, MS; Zohra Prasla, BBA; Matthew Harrison, BS; Karanjit Kooner, MD

Dallas Veterans Affairs Medical Center4500 South Lancaster Road

Dallas, TX 75216Department of Ophthalmology, University of Texas Southwestern Medical Center

Dallas, TX 75390

MATERIALS AND METHODSStudy Design and Participant Selection:

From July 2005 to July 2009, The Dallas Glaucoma Registry (DGR) has compiled epidemiological data for over 4,000 glaucoma patients seen at UT Southwestern Medical Center and its affiliated clinics in the North Texas region. Our research population consisted of 1800 United States military veterans, both male and female, who have been followed for glaucoma or a risk of developing glaucoma at the Dallas VAMC. We included the following:

• Patients who have been seen two or more times by an ophthalmologist at the Dallas VAMC

• Patients with sufficient necessary information in their medical chart, including gender, race, diagnosis, visual field records, IOP measurements, medications prescribed, etc.

• Patients who have primary or secondary glaucoma (not tertiary to other disease processes).

Data Collection and Analysis:

Data was gathered by reviewing medical charts and completing a custom form for each patient. (Figure 1) We recorded information on ocular characteristics such as intraocular pressure (IOP), central corneal thickness (CCT), cup-to-disk ratio (C/D), medications, surgeries, visual fields (VF), and visual acuity (VA) as well as demographic data such as age, gender, and ethnicity. Each patient was enrolled only once in the registry, regardless of the number of clinic visits.

We analyzed several risk factors based on four glaucoma subtypes: Primary Open Angle Glaucoma (PAOG), Suspect, Secondary, and Narrow Angle Glaucoma/Angle Closure Glaucoma (NAG/ACG). We used means and standard deviations to characterize quantitative variables and percentages to describe categorical variables. The data was transferred to Microsoft Excel (Microsoft Corporation, Seattle, WA, USA) and risk factors were analyzed using SAS 9.2v (SAS Institute, Cary, NC, USA) and SPSS (SPSS Inc., an IBM Company, Chicago, IL, USA).

INTRODUCTION Approximately 5 million veterans in the U.S. use the services of VA

medical facilities which provides many specialized medical programs and treatment options unique to their needs . In ophthalmology, these include routine and specialized eye care, Blind Rehabilitation Centers, Vision Impairment Services, and social work—needs.

The VA Health Service has more than 300,000 patients afflicted with glaucoma, the second leading cause of blindness .2 Also, the incidence of blindness is more than 10 times higher in veterans as compared to the general population. 1At the Dallas Veterans Affairs Medical Center (VAMC), 30% of 250 blind patients were so due to glaucoma. Unfortunately, there is very little information on glaucoma in veterans. Thus, the data collected for this study will provide healthcare professionals with invaluable information regarding glaucoma in this patient population thereby improving the quality of veterans’ health outcomes.

CONCLUSIONS• Glaucoma suspects were the most prevalent group (46.8%) in this study.

• Of the POAG eyes, nearly a third had severe VF defects, 40% were treated by 3 or more medications and more than a quarter required surgery.

• Of the eyes diagnosed with secondary glaucoma, nearly 30% were post intraocular surgery and a quarter had a history of trauma.

REFERENCES• Marcussen, BL, Newcomb RD. Mil Med1994 Jan;159(1):10-5.• Quigley HA, Broman AT. The number of people with glaucoma

worldwide in 2010 and 2020. Br J Ophthalmol. 2006;90:262–267

SUPPORTThis research is supported in part by an unrestricted grant fromthe Society to Prevent Blindness New York, NY.

RESULTS AND DISCUSSIONIn this study of 1800 patients (3600 eyes), glaucoma suspect was

the most prevalent diagnosis (46.8%). These patients were on average the youngest of all four groups and had the smallest average C/D ratio (0.55). Interestingly, however, suspicious optic disk (SOD) was the most common risk factor for these patients followed by elevated IOP.

The second most prevalent group was POAG (40.6%). The mean C/D ratio for POAG was 0.71, which was higher than secondary, suspect, and NAG/ACG (0.62, 0.55, and 0.29, respectively). In addition, the average number of medications taken was 2.21 for POAG, 1.68 for secondary, 1.55 for NAG/ACG, and 0.56 for suspect. 465 (31.8%) POAG eyes had visual field (VF) defects that were described as “severe,” or in other words, had a mean defect greater than -12. (Figure 2)

Eyes diagnosed with secondary glaucoma were the third most prevalent (4.6%). Of these, 49 (29.3%) had glaucoma secondary to surgery and 42 (25.1%) had glaucoma secondary to trauma. (Figure 3)

The NAG/ACG group was least prevalent (4.3%). However, they had the highest number of surgeries (76.6 %) compared to POAG (26.7%), secondary (26.1%), and suspects (1.8%).

a history of trauma.

Figure 2

Figure 3

DALLAS GLAUCOMA REGISTRY(1)Name: _____ (2) Hospital No.: ___________ (3) Date first seen in Dallas _________

(1)Date of last exam (5) DOB _ __

(6) Sex: 1 | 2 1= M, 2 = F

(7) Hosp.: 1 | 2 | 3 | 4 1 = Aston, 2 = PMH, 3 = VA, 4 = JPS

(8) Race: 1 | 2 | 3 | 4 | 5 | 6 1 = White, 2 = Black, 3 = Hispanic, 4 = Asian, 5 = East Indian, 6 = N/A, 7 = other

(9) Glaucoma status 1 | 2 | 3 1 = stable, 2 = undetermined, 3 = unstable;

(10) Glaucoma Diagnosis (A) OD: 0│1 | 2 | 3 | 4 | 5 │6│7_| (B) OS: 0 │ 1 | 2 | 3 | 4 | 5 │6│7 |

0= normal; 1 = POAG; 2 = LTG/NTG; 3 = glaucoma suspect; 4 = secondary; 5 = ACG/NAG, 6= childhood; a) primary; b) secondary; c) juvenile; 7=other__________________

•VF defects (A) OD 0 | 1 | 2 | 3 (B) OS 0 | 1 | 2 | 3 0 = normal, 1 = mild, 2 = moderate, 3 = severe

•Initially diagnosed in Dallas? 1 | 2 | 1 = yes, 2 = no (13) C/D ratio (A) OD ________ (B) OS ________

(14) Glaucoma surgery: (A) OD 1 | 2 | 3 | 4 | 5 | 6 | 7 (B) OS 1 | 2 | 3 | 4 | 5 | 6 | 7 1 = ALT/SLT, 2 = LPI, 3 = trabeculectomy, 4 = glaucoma shunt, 5 = cyclodestruction, 6 = no surgery, 7 = other __________________

•Glaucoma medications: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 1 = prostaglandin analogues (Xalatan, Travatan, Lumigan, Rescula), 2 = beta blockers (Timoptic,

Betimol, Betoptic, Betagan, Carteolol, Istalol), 3 = alpha agonist (Iopidine, Alphagan 0.2%, 0.15%, 0.1%), 4 = topical CAI (Trusopt 2%, Azopt 1%), 5 = system CAI (Neptazane 25 mg, /50 mg, Diamox 250/500mg),

6 = sympathomimetic (Propine), 7 = miotics (Pilocarpine 2%, 4%, 6%, Carbochol .75%, 1.5%, 3%), 8 = no meds, 9 = other ____________________

• Number of medications: ______________

• Glaucoma suspect: 1 | 2 | 3 | 4 | 5 1 = increased IOP, 2 = suspicious disc(s), 3 = strong family history, 4 = suspicious VF or NFL, 5 = other ___________

•Secondary glaucoma: 1 | 2 | 3 | 4 | 5 1 = rubeotic, 2 = traumatic, 3 = inflammatory, 4 = post-surgical, 5 = other _______

•ACG/NAG: 1 | 2 | 3 | 4 1 = primary acute angle closure, 2 = plateau iris, 3 = chronic angle closure, 4 = CMG, 5 = others _________________________

(20) Vision Best Corrected (A) OD: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | (B) OS 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |

1= 20/20, 2= 20/40, 3=20/60, 4= 20/80, 5=20/100, 6= 20/200, 7= CF, 8= HM, 9=LP, 10=NLP, 11=Prosthesis

(21) IOP (mmHg) (A) OD _____________ (B) OS _____________

(22) CCT (µ): (A) OD____________ (B) OS______________ 

Figure 1: Form Used To Collect Data From Patient Charts

Type (%)

Age (±SD)

IOP (±SD)

C/D (±SD)

CCT (±SD)

POAG (40.6)

74.15 (10.60) 15.98 (4.85) 0.71 (0.21) 538.02 (69.35)

Suspects(46.8)

67.01 (11.68) 17.17 (4.28) 0.55 (0.19) 548.90 (43.57)

Secondary(4.6)

69.48 (11.28) 18.77 (9.57) 0.62 (0.26) 555.27 (66.67)

NAG/ACG(4.3)

72.05 (10.41) 17.23 (5.48) 0.59 (0.29) 554.47 (50.89)

Table 1: Risk Factors Based on Types of Glaucoma