Fifteen regional studies published over the last six decades surveying prevalence, mortality and hospital admissions have suggested that Scotland is amongst the highest risk nations for multiple sclerosis (MS) in the world. However, substantial intranational variation in rates (between regions) has been described in numerous countries, including in the only previous Scottish national survey, which used hospital admission data, to address this issue. Against this backdrop, the Scottish Multiple Sclerosis Register (SMSR) was established in 2010 to prospectively collect nationally comprehensive incidence data and to allow for regional comparisons.
Here, we present the SMSR and analyse the variation in crude and age-sex standardized incidence rates, lifetime risk (cumulative incidence), and the sex distribution of cases and rates, between the 14 administrative Health Boards or regions of Scotland: 01 January 2010 to 31 December 2017.
The overall incidence rate (number each year) for Scotland was 8.76/100,000 person-years (standardized: 8.54). Regional incidence rates varied significantly-up to threefold-between Health Boards (p < 1 × 10-13). The national female-to-male sex ratio was 2.3:1, but this too varied regionally (outlier regions result in a range from 1.0 to 4.2:1). Lifetime risk ranged from 19.9/1000 for females in Orkney (58.98°N) to 1.6/1000 for males in the Borders (55.60°N). Comparison with a previous national survey suggests that these differences are longstanding. In 6 of 14 regions the lifetime risk for women exceeds 1%.
This study introduces a national incidence register: a valuable research tool and the result of substantial public investment. The wide variation in incidence rates and sex ratios between regions, in a relatively homogenous population, raises questions for future study.
Scotland is considered to be the MS captial of the World. As Scots and the Brits travelled to Canada they took their MS with them, such that areas of Canada also claim this mantel. Based on current figures, the lifetime risk in the Orkney Islands (Population about 22,000) is about a staggering 1 in 50 females to about 1 in 500 at the border….So time for some Vitamin D supplementation, EBV vaccination etc by the Scottish Government if ever there was one. This is the place to look at modifications of life style to determine how preventable MS is.
We had a great time visiting Stornoway….maybe the Islanders will invite us for another reasearch day in Scotland…I’m sure NDG would be up for a climb on the Old man of Hoy