Continuing the theme of this column, we ask the question: Is the practice of contact lens fitting homogenous in the two largest North American countries?

Among optometrists, for example, training in Canada and the United States is very similar, and all U.S. and Canadian optometry programs are accredited by the Accreditation Council on Optometric Education (ACOE). Canadian students are allowed to challenge the U.S. National Board exams and vice versa, with no need for further education or training.

Only two universities offer optometry degrees in Canada: The University of Waterloo is English-speaking and has 90 students per year; The University of Montreal is predominantly French-speaking and has up to 48 students per year. Because of the lack of opportunity for optometric education in Canada, many students seek training in one of the 23 U.S. universities and then return to Canada to practice. With such similarity of education and common movement across borders, it would be easy to assume that the fitting practices would also be broadly the same; however, the latest publication in January 2018 from the International Contact Lens Prescribing Survey Consortium (Morgan et al, 2018) reveals some distinct differences.

Comparing the Markets

Though the two countries occupy a similar land area, the population of Canada is significantly lower at 36.6 million compared to 324.5 million in the United States. Despite the huge difference in population density, around 80% of the population of each country lives in urban districts (www.worldometers.info/world-population/population-by-country ).

There are approximately 42,000 optometrists and 60,000 opticians in the United States (Bureau of Labor Statistics, statista.com, studentscholarship.org) and around 6,000 optometrists (Canadian Association of Optometrists) and 6,500 opticians (Opticians Association of Canada) in Canada. This indicates that both populations should have similar access to contact lens fitters.

Fits and refits to females represent 70% of both countries’ data sets, and the mean age of patients attending is also the same at 37 years. However, there is a major difference in the new fit versus the refit data. For Canada, 41% of the patients were new fits, which is a good indicator of the growth in the Canadian contact lens market. In stark contrast, new fits represented only 15% of patients among the U.S. respondents.

Which Material?

The switch from hydrogel to silicone hydrogel materials seems to have progressed solidly in both countries. Canada has one of the highest percentages of fitting silicone hydrogels of all countries surveyed at 80%, and the United States is only slightly lower at 76%.

Lens Care and Replacement

Which Care Product? Canada appears to buck the worldwide trend of minimal prescribing of peroxide lens care systems. In fact, peroxide use in Canada has been increasing, and now around one-third of all contact lens wearers are recommended to use a peroxide system. U.S. figures mirror those of most of the other countries surveyed, with only 17% of patients being recommended to use peroxide.

Daily Disposables (DD) Canada was an early adopter of DD lenses, and this market has shown steady growth over the past four years: this segment now stands at 49% in Canada, which is up from 24% in 2013 and 42% in 2015. This is much higher compared to the United States, where there was growth in the market in 2013 and 2015 (17% and 30%, respectively), but 2017 saw a drop in the numbers of patients being fit with a DD modality to only 23% in this survey.

Frequent Replacement Practitioners in the United States who choose to prescribe a frequent replacement modality are more likely to fit their patients with a monthly replacement lens (55%) compared to their Canadian counterparts (34%). This would appear to be their preferred alternative to the daily disposable (23%) or the two-week replacement (22%) modalities. Two-week replacement lenses in Canada occupy just a small segment of the market at 15%.

Extended Wear This category shows a marked difference between the two countries. The U.S. extended wear (EW) market continues to show growth, reporting 15% in this category, which is a little above the average for all of the surveyed countries combined. The United States has historically been strong in this sector, largely because of the loyal patient demand created when the modality was launched early in the U.S. markets ahead of other countries and before the risks of EW were fully understood. The U.S. material choice for soft lens EW appears to have swung heavily toward silicone hydrogels, with 99% now reported as fit in this contact lens material compared to just 55% in 2015.

In stark contrast, fitting contact lenses for EW remains out of character for Canadian practitioners, with the percentage of fits dropping to just 1%.

Presbyopia

Both countries have a similar median age, with Canada being just slightly older at 41 years compared to 38 years in the United States. Canadian fitters are slightly more proactive in fitting a presbyopia correction (either multifocal lenses or monovision) to two-thirds of their presbyopes compared to their U.S. counterparts who fit less than half of their presbyopes with a presbyopia-specific correction. Almost half of Canadian presbyopes are fit with multifocal lenses compared to only 29% of U.S. presbyopes.

Monovision remains more common in both of these two countries compared to almost every other country in the Eurolens survey, but it lags behind multifocal contact lens fits. Within Canada, one in five presbyopic patients is fit with monovision. This number is one in six in the United States. The one notable exception around the world is New Zealand, which reports the highest use of the monovision modality (one in three presbyopes is fit with monovision).

Myopia Control

Myopia control is one of the new “big things” in eye care. GP orthokeratology lenses and soft lenses for myopia control have piqued huge interest among practitioners and members of the public around the world. The conundrum for manufacturers is that, despite the interest, the target market is small relative to that of their mainstream products.

In January 2018, Canada saw the launch of a soft lens with CE and Health Canada approval for myopia control. This lens is already available in Europe, Australia, New Zealand, Hong Kong, Singapore, and Malaysia. Canada already leads the way for fitting myopia control products at 5% of new fits, though the United States is also an early adopter with its result of 2%. The availability of a soft lens with an approved indication for myopia control in Canada may create a flurry of activity in those practitioners who were previously wary of fitting lenses off-label and may result in higher numbers of patients being fit with a myopia control modality. The results of the 2018 Eurolens survey (which will publish in January 2019) will provide an early indicator of whether this landscape will be affected by the launch of an approved product into the arena.

Summary

While there are many similarities between contact lens practices in these two North American countries, this survey shows that they are far from homogenous. The two contact lens-wearing populations seem to have similar demographics for age and gender, though the Canadian contact lens market seems more vibrant with almost equal proportions of new fits to refits. If we estimate that around 20% of wearers drop out each year (Dumbleton et al, 2013; Sulley et al, 2017), then the reported low number of new fits in the United States (17%) may be concerning because it may not be enough to replenish the dropouts.

The U.S. market maintains its historical higher use of EW, whereas Canada’s EW market barely exists. The Canadian soft lens market favors DD lenses much more compared to the U.S. market. Those patients using a care system are more likely to have a peroxide system recommended in Canada than in the United States; however, most patients in both countries use a multipurpose solution care regimen. CLS

For references, please visit www.clspectrum.com/references and click on document #268.