Screening in community venues could reduce the vision loss associated with glaucoma.
"It really can be an effective way of identifying patients with glaucoma and other sight-threatening diseases," said L. Jay Katz, MD, chief of the Wills Eye Glaucoma Service, Philadelphia.
He gave an overview of the new screening approaches in the Shaffer-Hetherington-Hoskins Lecture at Glaucoma 360, the annual meeting of the Glaucoma Research Foundation.
"As our population is aging there has been reference to the tsunami of chronic disease that's going to hit us, and part of that is glaucoma," said Dr. Katz, citing a projected 40% increase in glaucoma prevalence in the next 10 years.
Glaucoma is particularly common in underserved populations, and is the leading cause of blindness among African-American and Hispanic people in the United States, he added.
Early detection could significantly reduce this vision loss, he said, and could save money because the disease is less expensive to manage in its early stages.
But "historically screening for glaucoma has been met with very little success," he said.
He gave the example of a program in the 1950s that screened about 10,000 factory workers. Only about 2% were identified as glaucoma suspects.
"That's a pretty low yield for a monumental effort," he said.
Not only have the screening programs failed to find much glaucoma, they have not been able to treat most of the cases identified.
"Even if you provide free care only about 20% often show up for any of their follow-up," Dr. Katz said.
As a result, in 2013 the U.S. Preventative Services Task Force (USPSTF), reviewing the track record of glaucoma screening found that "the overall certainty of the evidence is low, and the USPSTF is unable to determine the balance of benefits and harms of screening for glaucoma in asymptomatic adults." It also warned of a risk of overtreatment.
The American Academy of Ophthalmology issued a rebuttal, arguing among its other points that everyone with the disease should be treated to prevent severe consequences in a minority, and pointed out that vision loss affects daily activities and quality of life.
Previous screening efforts have fallen short of their objectives largely because they have not reached high-risk populations, said Dr. Katz.
He also cited other barriers to glaucoma care including patients' lack of knowledge about the risk, lack of trust, lack of access to eye-care providers, need for multiple follow-ups once treatment is initiated, poor adherence to glaucoma medication, language, transportation, lack of insurance and other funds to pay for care.
To test approaches for overcoming these barriers, the Centers for Disease Control and Prevention (CDC) and Wills Eye have conducted two initiatives to reach underserved populations in Philadelphia, one using mobile eye care and the other using telemedicine.
The mobile program sought to identify and engage African Americans 50 years of age and older, and other residents of underserved communities aged 60 years and older who were most vulnerable to glaucoma, and to provide educational workshops, eye examinations, and follow-up treatments at community sites.
Transporting their equipment in a van, the providers gave 30-minute presentations including a 10-minute video and the offer to review brochures in Spanish, Mandarin and Russian. They also offered glaucoma screening appointments. Surveys showed that the presentations increased participants' knowledge about glaucoma.
The education program was so successful that word spread, and more people came for screenings than had attended the education sessions. Of the 1,506 scheduled, 1081 attended and an additional 598 walked in.
Examinations included slit-lamp exams, intraocular pressure measurement, visual field testing and optic nerve/fundus photos.
The clinicians diagnosed new glaucoma in 4%, existing glaucoma in 6.6%, suspected glaucoma in 21.4% and antatomically narrow angles in 12%. Another 4% had cataracts, macular degeneration, diabetic retinopathy or dry eye.
The clinicians recommended eye drops or laser therapy for glaucoma, and laser therapy for anatomically narrow angles. They recommended follow-ups for suspected glaucoma and referred everyone else to local eye doctors. Follow-up adherence to these recommendations was 61.2%.
In the telemedicine project, 7,200 people were identified by electronic records as being in high risk populations and invited to a screening at their primary care offices. Five hundred forty of these patients, along with 365-walk-in patients underwent fundus photography of the optic
nerve and macula and tests of visual acuity and IOP, and provided their medical and family histories in primary-care offices.
Of the 905 screened, 540 had abnormal or unreadable images, or ocular hypertension and were referred to full eye exams, also in the primary care offices, or fast tracked to local ophthalmologists. Four hundred nineteen participated in these follow-ups appointments, with 338 of them continuing into the second phase of the study.
Of the 338, 80.5% were diagnosed with an eye condition, including 161 with suspected glaucoma, 35 with glaucoma, and the others with narrow angles, ocular hypertension, diabetic retinopathy, neuropathology, and other pathologies.
Overall the screening exam agreed with the follow-up exams in 86.3% of cases. The program was cost-effective, since the researchers estimated the costs per patient at $9.77, Dr. Katz said.
Philadelphia is not the only place experimenting with such screening efforts. Dr. Katz cited screening by ophthalmic techs in rural primary care clinics, with electronic health records reviewed by physicians at the Atlanta Veteran's Administration Eye Clinic.
In Baltimore, screening is being done in churches, senior apartments, community health centers and other community sites with follow-up tests done by the Veteran's Administration.
And in Alabama, optometrists conduct screening at Walmart stores with follow-up by fellowship-trained glaucoma specialists.
"Ultimately, I hope we're going to reduce the rate of patients with vision loss," Dr. Katz said.