INTERNATIONAL PRESCRIBING
International
Contact Lens Prescribing in 2005
An
analysis of more than 18,000 contact lens fits from 15 countries in 2005 reveals
the diversity of contact lens practice worldwide.
By Philip B. Morgan, PhD, MCOptom, FAAO,
Nathan Efron, DSc, MCOptom, FAAO (DipCLP), Craig A. Woods, PhD, MCOptom, DipCLP,
FAAO, Deborah Jones, BSc, FCOptom, DipCLP, FAAO, Alice Pesinova, Hans-Juergen Grein
Dr. med., Dipl.-Ing. (FH), Ioannis G. Tranoudis, DO, MSc, PhD, Aris Chandrinos,
DO, MSc, Motozumi Itoi, MD, PhD, Eef van der Worp, BSc, FAAO, FIACLE, Geraint Phillips,
BSc, OD, MCOptom, DipCLP, Vadim Belousov, Magne Helland, BSc, MScOptom, FIACLE,
Inga-Lill Thunholm-Henriksson, Alex Ong, MSc, Lee Kai Hung, MSc, & Joseph T.
Barr, OD, MS, FAAO
This article presents our fifth annual survey of international contact lens prescribing trends. In the first half of 2005, we analyzed prescribing habits in 15 countries: Australia, Belgium, Canada, the Czech Republic, Germany, Greece, Japan, the Netherlands, New Zealand, Norway, Singapore, Russia, Sweden, the United Kingdom and the United States. In each country, we sent 1,000 surveys (or fewer in countries where this exceeded the total number of practitioners) to contact lens clinicians who were randomly selected from appropriate national registers.
The survey forms elicited prospective information about the type of contact lenses and care products prescribed to a maximum of 10 patients fit after the commencement of the study. We employed a system of weighting to better reflect the fitting practices of busier practitioners.
Demographics and Background Information
Table 1 shows that in 2005 we received information about 18,098 contact lens fits. In all countries, a majority of patients were female with only modest variance in the size of the female-to-male ratio, which ranged from 59 percent female in Norway to 73 percent in Greece. As in previous years, we see that most (64 percent) contact lenses are prescribed as 'refits' to existing wearers of lenses. This value can serve as an indirect sign of the health of a market, with low refit scores reflecting a more positive outlook because it means more new wearers are coming forward. The notable exception in our dataset is the United Kingdom, where practitioners prescribed 60 percent of contact lenses as new fits; this was the only country where new fits represented the majority. At the other end of the spectrum was the United States with only 24 percent new fits. The frequency of lens wear also demonstrates significant differences among markets, with 15 percent or more patients indicating they want lenses for part-time wear in Australia, Singapore and the United Kingdom. This proportion was 5 percent or less in Greece, Russia and in the United States.
Soft vs. Rigid Lenses
A key yardstick for contact lens usage is the amount of rigid lens prescribing (Table 2), which according to our data fell slightly this year to 10 percent of new fits and 11 percent of refits. These headline figures mask the significant variation among markets. Practitioners fit 2 percent or less of wearers with rigid lenses in Russia, Sweden and Norway, whereas the number is at about 20 percent or higher in Germany, the Netherlands and Japan (Figure 1).
Rigid lenses
It's evident that a number of our surveyed markets tend to use rigid lenses only for more complex fittings (Table 3). This is evidenced by the fact that spherical designs account for more than 50 percent of rigid lens fits in only four countries, including two of the three rigid lens "heavyweights" Japan and the Netherlands. In countries where rigid lens fitting is relatively uncommon, practitioners fit high proportions of toric lenses (Australia and the Czech Republic, for example), multifocal lenses (the United States), orthokeratology (Belgium) and extended wear (Australia and Norway).
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Figure 1. Prescribing trends in Japan and worldwide |
Respondents fit low-Dk lenses (less than 40 Dk) in only a minority of cases, with lenses manufactured from mid-Dk materials (40 Dk to 90 Dk) the most commonly prescribed. A significant exception is Japan, where 63 percent of rigid lenses prescribed are fabricated from high-Dk materials.
Orthokeratology A major new initiative within the contact lens industry is the use of lenses for orthokeratology, and for the first time this lens type has registered within the international survey, accounting for 1 percent of all fits. These lenses now account for 4 percent of fits in Australia and 5 percent of fits in Belgium, with all other markets reporting between 0 percent and 1 percent of fits.
Daily Disposable and Conventional Lenses
We continue to see dramatic differences among our surveyed markets in terms of the proportion of daily disposable lenses prescribed. These lenses range from 3 percent of all lens fits in the Netherlands and 4 percent in the United States (Figure 2) to more than 30 percent in Singapore, Norway and the United Kingdom (Figure 3). For new soft daily wear fits, lenses designed to be replaced less frequently than monthly are prescribed for about 2 percent of fits worldwide. Monthly lenses are the most commonly prescribed soft daily wear lens type in all countries with the exception of Japan, Singapore and the United States (where one-week to two-week replacement is the most widely prescribed). Spherical soft lenses remain the most prescribed daily wear design, although soft torics account for more than one-third of new daily wear fits in Germany, the Netherlands, Norway, Sweden and the United States.
Silicone Hydrogel Lenses for Daily Wear
The introduction of silicone hydrogels specifically marketed for daily wear has caused a significant shift in contact lens prescribing patterns. These materials now account for 30 percent and 25 percent of lenses prescribed as new daily wear fits in the United States and Canada respectively. The Canadian data represents a dramatic change since 2004 when this material accounted for 1 percent of fits. Furthermore, the recent introduction of the first silicone hydrogels into the large Japanese market has resulted in 4 percent of all contact lens fits using this new material. These latest results suggest that eyecare practitioners are rapidly accepting silicone hydrogel materials for the fitting of daily wear patients, coupled with wide scale availability provided by the lens manufacturers.
Figure 2. Prescribing trends in the US and worldwide. |
Soft Extended Wear
The increase in extended wear prescribing that followed the launch of the first silicone hydrogel materials in 1999 now appears to have reached a plateau, with practitioners fitting 10 percent of all contact lens wearers worldwide with soft extended wear lenses. The key market for this modality is Norway, where 24 percent of all fits (or 31 percent of soft lens refits) were with soft extended wear lenses. Most countries reported between 5 percent and 15 percent of fits as soft extended wear, and generally more than 90 percent of soft extended wear fits are with silicone hydrogel materials. Important exceptions here are Russia (78 percent with conventional materials) and the United States (48 percent).
Extreme Markets
Among our surveyed markets, the one that differs most from the typical world situation is Norway (Figure 4). Its use of rigid lenses is well below the average (2 percent for Norway vs. 10 percent for the world average), while Norwegian practitioners use many more daily disposable lenses (32 percent vs. 15 percent worldwide) and soft extended wear lenses (24 percent vs. 10 percent) than are generally employed around the world. Russia also represents a very different market; practitioners there fit only 1 percent of lens patients with rigid lenses, and their use of daily disposable lenses (6 percent vs. 15 percent worldwide) and silicone hydrogels for daily wear (2 percent vs. 11 percent) show rather different fitting trends than those elsewhere. Australia's market most closely resembles the overall global picture.
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Figure 3. Prescribing trends in the UK and worldwide. |
This survey was funded by the sponsors of Eurolens Research: Bausch & Lomb Inc, Alcon Laboratories (UK) Ltd, Advanced Medical Optics (UK) Ltd, CIBA Vision (UK) Ltd, Clearlab UK Ltd, CooperVision Ltd, Johnson & Johnson Vision Care, Menicon Co. Ltd., and Sauflon Pharmaceuticals Ltd. Additional funding was provided by Johnson & Johnson for Greece, by the Norwegian Optometric Association for Norway and by Bausch & Lomb Benelux for the Netherlands and Belgium.
Dr. Morgan is the research manager of Eurolens Research at the University of Manchester, UK.
Dr. Efron is research professor in the School of Optometry at the Queenland University of Technology, Brisbane, Australia.
Dr. Woods is the research manager of the Centre for Contact Lens Research at the University of Waterloo, Waterloo, Canada.
Dr. Jones is the clinic director and head of the Pediatric and Special Needs Clinic at the School of Optometry, University of Waterloo, Waterloo, Canada.
Ms. Pesinova is a contact lens practitioner in Prague, Czech Republic.
Figure 4. Prescribing trends in Norway and worldwide. |
Dr. Grein is a professor of optometry at the University of Applied Sciences, Jena, Germany.
Dr. Tranoudis is the professional affairs manager, Central & Southeastern Europe, Johnson & Johnson Vision Care.
Dr. Chandrinos is assistant professor in the Department of Optics at the TEI of Athens, Greece.
Dr. Itoi is an associate professor in the Department of Ophthalmology at Juntendo University, Tokyo, Japan.
Dr. van der Worp is a lecturer at the school of optometry of the Hogeschool Utrecht and a researcher at the University of Maastricht department of ophthalmology in the Netherlands.
Dr. Phillips is the clinic director of the Department of Optometry at Auckland University, Auckland, New Zealand.
Mr. Belousov is the editor of the Journal of Optometry, Moscow, Russia.
Dr. Helland is an associate professor at the Department of Optometry and Visual Science at Buskerud University College, Kongsberg, Norway.
Dr. Thunholm-Henriksson is a senior lecturer, Karolinska Institutet, Stockholm, Sweden.
Drs. Ong and Lee practice optometry in Singapore.
Dr. Barr is editor of Contact Lens Spectrum magazine. He's a professor and associate dean for clinical services and professional program at The Ohio State University College of Optometry.