INTERNATIONAL PRESCRIBING

International Contact Lens Prescribing in 2008

Our report on a prospective analysis of more than 22,000 contact lens fits in 27 countries during 2008.

By Philip B. Morgan, PhD, MCOptom, FAAO, FBCLA; Craig A. Woods, PhD, MCOptom, DipCLP, FAAO; Ioannis G. Tranoudis, DO, MSc, PhD; Nathan Efron, DSc, MCOptom, FAAO (DipCLP); Razmig Knajian, OD, FAAO, FIACLE; Christina N. Grupcheva, MD, PhD, FEBO; Deborah Jones, BSc, FCOptom, DipCLP, FAAO; Kah-Ooi Tan, BOptom (Hons), PhD, MBA; Alice Pesinova; Ole Ravn, MScOptom; Jacinto Santodomingo, OD(EC), MSc, PhD, MCOptom, FBCLA, FAAO; Edit Vodnyanszky; Giancarlo Montani, FIACLE; Motozumi Itoi, MD, PhD; Jolanta Bendoriene, MD, PhD; Eef van der Worp, BOptom, PhD, FAAO, FIACLE; Magne Helland, BSc, MScOptom, FIACLE; Geraint Phillips, BSc, OD, MCOptom, DipCLP; José Manuel González-Méijome, OD, PhD, FIACLE; Simona Radu, MD; Vadim Belousov; Mirna Stabuc Silih, MD, PhD; John C. Hsiao, BA, OD, FIACLE; & Jason J. Nichols, OD, MPH, PhD, FAAO

This is our seventh consecutive year of reporting on the prescribing patterns for contact lenses worldwide and describing the distinct nature of each contact lens market. In 2008 we tracked prospective information on 22,429 contact lens fits in 27 contact lens markets. Our methodology has remained consistent for each year that we've collected the data. In common with all previous years, up to 1,000 survey forms were randomly distributed to contact lens practitioners (ophthalmologists, optometrists and/or opticians depending on the market), and recipients anonymously recorded information about the first 10 or fewer patients prescribed with contact lenses after receipt of paper or electronic survey forms.

Contact Lens Wearer Demographics

Overall, two-thirds of the contact lens patients fitted with contact lenses were female, with this value ranging from 56 percent of patients in Italy to 83 percent in Russia (Table 1). The average age at fitting was 29.9 years, with a difference of a decade between the country with the highest mean age (the United Kingdom at 35.1 years) and that with the lowest (Lithuania at 24.9 years). Typically, the more developed markets have higher mean ages at fitting (greater than 32 years for Australia, Canada, Denmark, the Netherlands, Norway, New Zealand, the United Kingdom and South Africa) compared with younger patients in the developing markets, mainly in eastern Europe and across the Middle East (less than 28 years for Bulgaria, China, Czech Republic, Egypt, Jordan, Kuwait, Lithuania, Romania, Russia, Slovenia and Taiwan).

Table 1. Demographic information for the 27 countries surveyed in 2008.

There was a wide variation in the proportion of lenses prescribed as ‘new fits’ (i.e. to patients who are not existing contact lens wearers). This parameter ranged from 9 percent of lens fits in China to 77 percent in Romania (Figure 1), although there was no apparent trend between this parameter and the type of contact lens market. Overall, about seven in 10 contact lens fits around the world are to existing contact lens wearers, an observation that accounts, in part, for the generally slow growth in contact lens use worldwide.

Figure 1. The proportion of contact lens fits reported as ‘new fits’ (to patients who have not previously worn contact lenses or to those who have spent considerable time out of lenses) versus wearer age. See Table 1 for abbreviations.

Rigid Lenses

Rigid lens prescribing accounted for 9 percent of fits (including 1 percent of fits for orthokeratology) (Table 2), the same values as for 2007. Japan and the Netherlands again reported high levels of rigid lens use, each at 24 percent of all lens fits. Orthokeratology prescribing appears to be focused on a small number of markets of relatively high activity (4 percent or more of all fits): Bulgaria, Hong Kong and the Netherlands. Overall, the proportion of orthokeratology lenses has risen from 0 percent to 11 percent of rigid lens fits in recent years (Figure 2), albeit against the declining use of rigid lenses in general (14 percent of all fits in 2002 to 9 percent in 2008).

Figure 2. Rigid lens designs from 2002 to 2008.

Table 2. Breakdown of lens fits into six key categories of lenses. See Table 1 for country abbreviations.

Mid-Dk (40-to-90 units) and high-Dk (greater than 90 units) materials dominate those selected for rigid lens prescribing, with only Canada prescribing a high proportion of low-Dk materials (68 percent) (Table 3). In some markets, a high proportion of rigid lenses prescribed are torics, with these lenses accounting for more than half of fits in Jordan, New Zealand and the United Kingdom.

Table 3. Detailed information for prescribed rigid lenses only. See Table 1 for country abbreviations. Data presented for countries reporting >300 lens fits. EW = extended wear. Data for materials and designs pertain to daily wear new fits only.

Soft Lenses

In all markets, soft lenses were prescribed for a large majority of wearers, from 71 percent in the Netherlands to 100 percent in China. Daily disposable lenses continued as the lens type with the most varied frequency of prescribing around the world. In Denmark, respondents prescribed 64 percent of all wearers with daily disposables lenses, a value that rises to 87 percent if only daily wear spherical soft lenses are considered. In fact, Denmark's high use of daily disposables and relatively low use of silicone hydrogels for daily wear makes it the contact lens market that is most disparate from the global average (Figure 3). Daily disposable lenses account for less than 10 percent of lenses prescribed in markets such as Canada, China and the Netherlands.

Figure 3. Distribution of overall fitting characteristics for Denmark (inner ring) and the global average (outer ring).

Toric lenses account for 23 percent of new soft lens fits worldwide (Table 4) with considerable variation between markets; these lenses account for only 4 percent of soft lenses prescribed in Russia compared with more than 40 percent of fits in Denmark, Spain and Jordan. Cosmetically tinted lenses account for a very low proportion of fits in many markets, but are popular (more than 10 percent of new soft lens fits) in Bulgaria, China, Egypt and Jordan. Multifocal and monovision lenses still account for a relatively small number of soft lens fits at 7 percent globally.

Table 4. Detailed information for prescribed soft lenses only. See Table 1 for country abbreviations. Data presented for countries reporting >300 lens fits. EW = extended wear. Data for materials, designs and replacements pertain to daily wear new fits only.

The increased availability of silicone hydrogel materials as a daily wear option has resulted in respondents prescribing these lenses for more than 40 percent of new soft lens fits in markets such as Australia, Canada and Jordan. Figure 4 shows the increase in the use of silicone hydrogels for daily wear spherical fits from close to zero in 2002 to about 20 percent in 2008. Soft lens extended wear remains an infrequently prescribed modality, accounting for only 7 percent of fits worldwide. This value is considerably greater in Lithuania and Norway. CLS

Figure 4. Soft lens materials from 2002 to 2008.

This survey was funded by the sponsors of Eurolens Research at the University of Manchester: Bausch & Lomb Incorporated, Alcon Laboratories (UK) Limited, Advanced Medical Optics (UK) Limited, CIBA Vision (UK) Limited, CooperVision Limited, Johnson & Johnson Vision Care, Menicon Co. Ltd. and Sauflon Pharmaceuticals Limited. Additional funding was provided for the following: United Arab Emirates, Australia — Optometrists Association Australia; Bulgaria, Egypt, Hungary, Jordan, Kuwait, Romania, Slovenia, South Africa — Johnson & Johnson Vision Care; Norway — the Norwegian Optometric Association; Netherlands — Bausch & Lomb Benelux; China, Hong Kong, Taiwan — CooperVision Inc.; Spain — Spanish College of Optic-Optometrists.