title: Major lower limb amputation in England 2003-2013; The North/South, Gender and Ethnic Divide
Creators: name: Ahmad, N
Publisher: name: University of Liverpool Repository
Year: 2017

description: Background: The vast majority (&gt;90%) of the 4000 major amputations undertaken in England every year in people aged 50 and over are related to peripheral arterial disease (PAD). Although it has the same underlying pathology as coronary heart disease similar epidemiological enquiry into inequalities has been lacking. Aim: To a) describe the prevalence of major lower limb amputation across England in people aged 50-84 highlighting variations across regional, gender and ethnic groups b) determine the influence of geographical location, gender and ethnicity on risk of amputation both with and without revascularisation and c) perform a validation study to compare the sensitivity and specificity of hospital episode statistics database (HES) to hospital records. Methods: Age standardised prevalence rates of amputation and revascularisation over a six year period (2003-2009) were calculated using HES as the numerator and census data as the denominator. The outcome measures ‘amputation with’ and ‘without’ revascularisation were created if the two procedures could be linked and used as a proxy for accessing services. The above to below knee ratio was also calculated. Logistic regression determined the odds of an amputation with and without a revascularisation unadjusted and repeated after controlling for demographic and disease risk factors. Prevalence was then re-calculated over a longer ten year period, 2003-2013, to determine if the patterns highlighted previously remained. To validate HES data, all above knee amputations undertaken in three hospitals over three years had their co-morbidities extracted and compared with the HES database. 90% accuracy was set as the standard. Results: Between 2003 and 2009, 25 312 amputations and 136 215 revascularisations were undertaken of which 7543 cases were linked. The prevalence rate, per 100 000, of amputation and revascularisation was 26.3 and 141.6 respectively with amputation rates significantly higher in Northern England (North 31.7, Midlands 26.0, South 23.1), men (men 37.0; women 15.9) and the Black community (White 22.2, Black 37.6, South Asian 13.3). The above to below knee amputation ratio was higher in the North (North 1.3:1, Midlands 1.2:1, South 0.9:1) and women (men 1:1 women 1.5:1). The odds of having an amputation with a revascularisation remained significantly higher in the North (OR 1.22; 1.13-1.33) after controlling demographic and disease risk factors. The higher odds in the Black population (OR 1.83; 1.54-2.17) were, however, fully attenuated. The odds of an above knee amputation were lower in men (OR 0.64; .55-.74), diabetics (.44; .55-.74) and those having endovascular only revascularisation (OR 0.82; .75-.90). Between 2003 and 2013, overall major amputation rates fell by 18% but the regional and gender inequalities remained. Rates in diabetics fell at a faster rate than non diabetics in both men (38% vs 24%) and women (43% vs 19%). The sensitivity target for HES co-morbidity codes was only reached by coronary heart disease although HES had specificity of over 90% for all co-morbidities. Discussion: Major lower limb amputation in England exhibited a North-South, gender and ethnic divide. Despite the overall prevalence falling over the last decade, inequalities remained. These differences were not wholly explained by variations in access, social deprivation or risk factors. A health needs assessment is required to understand and address these variations.