Multiple sclerosis is more prevalent in northern New Zealand than previously reported

Abstract

Background: There have been no studies of multiple sclerosis (MS) prevalence from New Zealand (NZ) in the past two decades, and only one in a northern NZ district. Our impression was that the local prevalence of MS was higher than previously published data would suggest. There is limited access to new treatments for MS in NZ.

Aims: The present paper aims to: (i). measure the prevalence of definite and probable MS in the Bay of Plenty (BOP), a North Island province, (ii). compare this with previous NZ studies, (iii). study the profile of disability in this population-based group and (iv). determine the proportion of MS patients who receive government funding for modern drug treatment (beta-interferons).

Methods: Patients were identified from a geographically and demographically defined area of the North Island of NZ, using multiple sources of case ascertainment and modern diagnostic criteria. All clinical records were reviewed and data were supported by a telephone interview. All patients' eligibility for -government-funded treatment with beta-interferon was considered.

Results: Eighty-six patients were identified as residents in BOP, NZ, on 15 January 2001. Excluding 'possible' cases, this represented a prevalence of 50/105 (95% confidence interval 40-62/105). Half of the population-based cohort had a disability defined as 'moderate to severe' (i.e. aids needed to walk, unable to take more than a few steps, or worse). Eleven patients (13%) had a primarily progressive form of MS. Eleven patients (13%) had the relapsing--remitting form of the disease and qualified for -government-funded treatment with beta-interferon.

Conclusion: The prevalence of MS in the defined region was twice as high as that reported from an adjacent area, the Waikato, 20 years previous. Our data will help to update NZ prevalence statistics and are of direct relevance to current funding issues for modern treatments which, in NZ, are presently limited to a proportion of patients with relapsing- remitting disease.