The scope of glaucoma in China

Jian Ge, Ningli Wang, Mingguang He

With at least 3% of people suffering from glaucoma and a population of 1.3 billion, glaucoma has become a major public health challenge in China. However, the number of eye care providers is much less than what is demanded, not to mention the quality of their practice. On the other hand, the widespread diversity of the practice pattern of glaucoma across China imposes further difficulties to reach the 'accessible, affordable, accountable' treatment of glaucoma.
In order to meet the pressing need to achieve consensus on the diagnosis and management of glaucoma, the Chinese Glaucoma Society proposed a new detailed guideline for glaucoma practice after extensive discussion of the panel members in 2008. This Chinese Preferred Practice Patterns for glaucoma is recognized as more practical and adaptable to Chinese practitioners than the one adapted from the American Academy of Ophthalmology in 2005. This practice pattern provides a standard guidance for the diagnosis and management of glaucoma. For instance, it redefines primary angle-closure glaucoma (PACG) as elevated IOP with occludable angle, with or without glaucomatous optic neuropathy and visual field defects. Acute PACG is classified as having pre-clinical, prodromal, acute-attack, chronic and absolute phases. This revised definition and classification scheme achieves a good compromise between the pre-existing Chinese scheme (1987) and the 'ISGEO' system.
Although various new surgical techniques have been developed in the last decades, trabeculectomy remains as the mainstay of surgical treatment for primary open-angle glaucoma (POAG). Scarring and overfiltration are two major causes for the failure of this surgery. The application of intra-operative mitomycin-C to the filtering site has proved to effectively inhibit fibroblast proliferation and greatly improve the long-term success of the surgery. With the increasing experience of the use of this antimetabole, the technique becomes safer and safer. Meanwhile, the releasable suture helps prevent the severe complications of hypotony, such as flat anterior chamber, choroidal detachment, hypotony maculopathy and even loss of vision, with no extra cost and instrumentation. Combined with these techniques, trabeculectomy dominates more than 85% of treatment for POAG in China, due to its safety, efficacy and low cost. It has become particularly helpful in underdeveloped areas.

On the other hand, there has been increasing evidence suggesting that phacoemulsification will provide a good visual outcome and control of IOP, particularly for the patients with angle-closure glaucoma and co-existing cataract. More and more glaucoma specialists in China are adopting this technique as a new option for angle-closure glaucoma. The original article, The preliminary outcomes of phacoemulsification on closed angle glaucoma (Ge et al.), is the most cited article in the Chinese Journal of Ophthalmology.
Although it has been widely accepted that lower IOP is the only effective treatment for glaucoma, the level to which the IOP should be lowered in order to stop further glaucomatous damage is still a controversial topic. The concept of target IOP is of great importance for the glaucoma doctors, because it emphasizes that there is a certain level of IOP that should be established and then modified based on individual patients' needs.
Fixed-combination of glaucoma medications is recently advocated and is now available in China. The pharmaceutical industry has endeavored to develop and promote new combinations aiming to improve efficacy and patient convenience, compliance and safety. But the issue of cost-effectiveness is important for the clinicians to consider particularly in underdeveloped areas. Thus, β-blockers still dominate in the medical treatment of glaucoma.
In the research area of glaucoma in China, epidemiological studies have been drawing more attention than ever. The Liwan Eye study, the Beijing Eye study and the ongoing Handan Eye study are the best known large-scale, population-based, epidemiological studies. These studies not only address the prevalence of glaucoma across the nation, but also provide important data on the natural history, risk factors and the efficacy of early intervention of the eye disease with the longitudinal components of the studies. Basic research is another area with great advancement. The introduction of a drug delivery system (DDS) with artificial vitreous body and obtaining pluripotent cells from somatic cells by reprogramming are major steps forward towards our dream of effective neuroprotection and transplantation therapy. Meanwhile, in a populous country like China, the large number of patients has becoming a great resource for the research and contributing to the understanding of the molecular mechanism and genetic pathogenesis of POAG.
In spite of all these advancements and achievements, much has to be done to improve the quality of practice for glaucoma in China. Large-scale, randomized, controlled trials are urgently needed to test the effectiveness and appropriateness of treatment in Chinese people.