Cataract surgical rates: is there overprovision in certain areas?

Short abstract

Healthcare providers should ensure that cataract surgical rates are beneficial to all

Cataract surgery rates in developed countries have increased dramatically over the past two decades. In England, the crude surgical rate in 1990 was around 2/1000,¹ by 1997 this had risen to around 3/1000² and by 2005 peaked at around 6/1000,³ an increase of close to 300% over 16 years. In Sweden, rates have been even higher; over a 9‐year period, the demand for cataract surgery rose steadily from 4.5/1000 in 1992 to 7.3/1000 in 2000.⁴ Encouraged by the “Action on Cataract” initiative in 2000, National Health Service units streamlined practice and massively increased surgical throughput. For a time, health policy became so obsessed by capacity building that fixed and travelling independent sector treatment centre facilities were set up irrespective of local need. Publicity and political hype far outstripped the actual capacity of these treatment centres, which contributed a mere 3% to national cataract surgical throughput. Inappropriate and politically enforced contracting at a local level, however, undermined a number of established high‐quality ophthalmological units, illustrating a profound lack of insight and planning behind these politically driven initiatives. This surgical bonanza, handed down by a government keen to gain popularity by cutting surgical waiting times, has paid scant attention to the possibility that surgery for early cataract may carry unacceptable risks. Misleading of the public by trivialisation of cataract surgery has occurred, with its presentation in the media as a quick and easy operation with a high success rate, and patients with minor visual symptoms frequently seek surgery in the belief that it is (virtually) risk free. The evidence, however, indicates otherwise. Following cataract surgery, up to 8% of patients may be dissatisfied with the outcome of their operation,⁵ with 7% reporting no change and 9% reporting increased difficulty at 6 months postoperatively in a sample of over 10 000 operations in the Swedish register.⁴ These figures are at odds with the “technical success” rates frequently quoted, which typically note the posterior capsular and/or vitreous loss benchmark rate of ⩽2%.⁶ However perfect though, an operation on an eye that does not really need surgery is unlikely to provide much visual benefit and carries an unjustifiable risk.

Improvements in technology, higher expectations by the public, greater confidence of surgeons in their ability to deliver a quality outcome and politically driven initiatives to reduce waiting times have contributed to this phenomenon in the UK and elsewhere. In the National Health Service (NHS), thresholds for listing for surgery have become increasingly lenient in visual acuity terms; in 1990 under 9% of eyes for surgery had an acuity 6/12 or better,⁷ by 1997 this had risen to 31%⁸ and in 2003 had reached 45% in an 8‐centre audit of over 16 000 cases.⁹

In this issue, Keenan et al¹⁰ (see p 901) provide an impressive and detailed review of cataract surgical rates across England from the 1960s onwards. The exponential rise in surgery is catalogued separately from Hospital Episode Statistics (and its precursor, the Hospital Inpatient Enquiry) and the Oxford Record Linkage Study, the latter capable of separate identification of “people” as opposed to “eyes” undergoing surgery each year. Data are aggregated for three separate periods and further broken down by age and gender. Recent data are mapped and graphed to illustrate large geographical variations in surgical rates between local authorities, and these are correlated against the social deprivation score for that locality. Interestingly, higher levels of social deprivation are correlated with higher surgical rates, suggesting that access to care seems not to be significantly compromised in socially deprived local authorities, although, as the authors correctly comment, other socioeconomic forces may be influencing these observed gradients.

Few questions have been asked about the appropriateness of this exponential rise in surgical rates, which have generally been packaged and received as good news. Following on this tide of promotion and surgical confidence, a reality check may now be necessary to ensure that patients are protected from unnecessary harm when seeking assistance for minor visual symptoms from early cataract. Overprovision, should this now be occurring, is wasteful and potentially damaging. Patient‐reported outcome and health‐gain data are urgently needed to better our understanding of the risk‐to‐benefit balance of surgery for early cataract. This will serve to inform patients, surgeons and commissioners on how best to use an undoubtedly excellent surgical procedure. Healthcare providers are duty bound to ensure that cataract surgery is appropriately applied with optimisation of benefit and minimisation of harm.