1. Epidemiology of Keratoconus in New Zealand: Aotearoa Research Into Keratoconus Study Part I
World Cornea Congress VII 2015
Akilesh Gokul PhD Candidate1
Dr Stuti Misra PhD1; A/Prof Dipika V Patel MRCOphth1;
Prof Charles NJ McGhee FRCOphth1
1. Department of Ophthalmology, Faculty of Medical and Health Sciences, University of Auckland, New Zealand National Eye Centre
The authors have no financial interests to disclose

2. The Aotearoa ARK Study: Part I
Purpose: To investigate the incidence, prevalence, demographic and basic clinical characteristics of keratoconus in New Zealand/Aotearoa
Prospective, longitudinal epidemiologic study focused on patients managed by optometrists
Hypothesis: The incidence and prevalence of keratoconus in New Zealand is higher than reported internationally, particularly among Māori and Pacific Peoples

3. Epidemiology of Keratoconus
Current prevalence estimates range from 6.8–2300 per 100,
Predominantly retrospective studies
Mainly hospitals and other tertiary centres
Variation in estimates due to location and population of interest
First community based epidemiology study of keratoconus in NZ since Sabiston 19788

4. The ARK Study: Part I - Methods
Nation-wide survey of optometrists in New Zealand
Survey filled in for every patient with keratoconus in 2 year study period ( )
DOB
Gender
Ethnicity
Established or new diagnosis
Refractive correction
Uncorrected and Best corrected VA
All patient data are anonymous

5. Preliminary Results: Age, Gender and New/Existing Diagnosis
N = 446 patients
Mean Age = 37.7 ± 15.7 years
Gender: % %
New/Existing: Existing 83.2% New 16.8%

6. Distribution of Keratoconus Across New Zealand by Region
Auckland 25.6%
Bay of Plenty 28.7%
Waikato 0.7%
Taranaki 1.1%
Gisborne 3.4%
Wellington 25.6%
Manawatu-Wanganui 4.3%
Nelson 2.9%
Canterbury 3.6%
Otago 4.3%

7. Distribution by Ethnicity
2013 New Zealand Census:
New Zealand European 74%
Māori 14.9%
Pacific peoples 7.4%

8. Types of Refractive Correction

9. Unaided Vision and Visual Acuity
20/140
20/30
N = 655 eyes
Mean Unaided VA
N = 835 eyes
Mean Best Corrected VA

10. The ARK Study: Part I - Preliminary Conclusions
Largest prospective, longitudinal study of epidemiology of keratoconus in NZ to date
n = 446 patients (>450 per year)
Relatively young population
Male and existing diagnosis predominance
Mostly Auckland, Bay of Plenty and Wellington
Māori and Pacific ethnicities over represented
Relatively poor uncorrected vision but good visual potential with refractive correction

11. References
Ljubic AD. Keratoconus and Its Prevalence in Macedonia. Macedonian Journal of Medical Sciences (1):58-62.
Brookes NH, Niederer RL, Hickey D, McGhee CN, Sherwin T. Recurrence of keratoconic pathology in penetrating keratoplasty buttons originally transplanted for keratoconus. Cornea 2009;28(6):
Rabinowitz YS. Keratoconus. Surv Ophthalmol 1998;42(4):
Nielsen K, Hjortdal J, Aagaard Nohr E, Ehlers N. Incidence and prevalence of keratoconus in Denmark. Acta Ophthalmol Scand 2007;85(8):890-2.
Ziaei H, Jafarinasab MR, Javadi MA, et al. Epidemiology of keratoconus in an Iranian population. Cornea 2012;31(9):
Kennedy RH, Bourne WM, Dyer JA. A 48-year clinical and epidemiologic study of keratoconus. Am J Ophthalmol 1986;101(3):
Jonas JB, Nangia V, Matin A, Kulkarni M, Bhojwani K. Prevalence and associations of keratoconus in rural maharashtra in central India: the central India eye and medical study. Am J Ophthalmol 2009;148(5):760-5.
Sabiston DW. The crazy cone. Australian Journal of Ophthalmology. 1978;6:43-45.

12. Acknowledgements Participating optometrists
New Zealand Association of Optometrists
Cornea & Contact Lens Society of New Zealand
New Zealand National Eye Centre
Supervisory Team