A new paper by Australian and US investigators examining glaucoma suspects has found more frequent six-monthly reviews actually cost the health system less and result in a higher number of diagnoses compared with annual reviews.
Additionally, it revealed Australian optometrists were less costly for reviewing these patients, at approximately $400 per diagnosis, compared with ophthalmologists at $600 per diagnosis, if only Australian Medicare was charged.
Recently published in Translational Vision Science & Technology, Centre for Eye Health (CFEH) and UNSW School of Optometry and Vision Science academics Dr Jack Phu, Professor Michael Kalloniatis and colleagues describe their findings as “seemingly counterintuitive”, but say they ultimately make sense from a financial and clinical perspective.
In the paper, the researchers stated that a common “clinical conundrum” for glaucoma suspect patients – in the ‘suspect’ part of their journey – is the optimal frequency of review.
While some patients are eventually diagnosed with glaucoma, many more are continually monitored as glaucoma suspects, therefore constituting a large part of clinical service and clinical cost. This motivated the researchers to compare the cost-effectiveness of differing review periods.
In the retrospective, cross-sectional review of patient records from the CFEH clinic in Sydney, open angle glaucoma suspects were allocated as “high risk” or “non high risk”, and thus reviewed six-monthly or 12-monthly, respectively. Risk allocation was based on two criteria: a less stringent criterion requiring the patient to have only one risk factor for glaucoma was compared against a more stringent criterion which required at least three risk factors. Thus, using a less stringent criterion was more likely to review in more “high risk” allocations compared to a more stringent criterion.
“Ultimately, we found that if clinics review glaucoma suspect patients with at least one risk factor on a six-monthly basis, the overall number of diagnoses is more than if 12-monthly reviews were used,” Phu said.
“We also found it surprising that more frequent reviews appeared to lead to lower cost per diagnosis. We had initially thought that more frequent visits would equal more costs, but it also makes sense clinically, as more frequent visits are probably more likely to lead to greater clinical confidence in the diagnosis.”
In the paper, the researchers stated that the relative lower costs related to more frequent visits, based on their model, was due to the sooner exit of patients from the glaucoma suspect pathway, shifting the cost away from this specific pathway.
They wrote: “Although seemingly counterintuitive, the less stringent/more frequent criterion resulted in fewer overall clinical visits, as patient reviews quickly diminished over time due to the patients reaching the exit points sooner. In essence, more frequent reviews (and therefore testing) may potentially improve the initial clinical confidence of stability or provide means for a more conclusive diagnosis (which may also be potentially earlier, as we have recently illustrated).
“In contrast, less frequent reviews may introduce more uncertainty, requiring more reviews later in the clinical course before a more conclusive diagnosis can be made.”
In terms of how community-based optometrists could interpret the findings for real world use, Phu said it demonstrated glaucoma suspect patients with risk factors can be reviewed in six-monthly intervals in the initial monitoring period, especially within the first 2.5 years.
“[This is because] the more frequent visits – and therefore clinical results – would lead to greater rates of diagnosis or discharge, both of which we hypothesise to be related to clinical confidence,” he said.
“Most importantly, more frequent reviews initially can lead to earlier diagnosis and prevention of vision loss.”
In future, Phu said he would like to apply the findings to other clinical populations, paradigms and more precise clinical measures, such as quantitative visual fields and OCT results.
The paper entitled: ‘Glaucoma suspects: The Impact of risk factor-driven review periods on clinical load, diagnoses, and healthcare Costs’, also involved co-authors Dr Katherine Masselos, from CFEH and Prince of Wales Hospital Ophthalmology, and Dr Michael Sullivan-Mee, from Eye Associates of New Mexico.
The paper can be accessed here.