Introduction: Cardiovascular disease (CVD) secondary to atherosclerosis accounts for 33% of all-cause mortality in the UK. Ethnic background is an established risk factor, with higher preponderance in South Asians due to a combination of genetic and environmental influences. Bradford has the highest density of South Asians per capita at 20%, predominantly originating from Pakistan.
Purpose: This prospective study sought to assess correlations between ethnic background and modifiable risk factors associated with CVD. Moreover, we wished to establish the proportion of patients who are appropriately prescribed statins for primary prevention of CVD, thereby quantifying compliance with UK NICE guidelines (CG181).
Methods: All patients who attended the emergency department (ED) of a busy teaching hospital within the UK with a complaint of “chest pain” were assessed. Attendances between August and October 2016 inclusive were included. Any patients with a subsequent positive troponin result suggestive of myocardial infarction were excluded. South Asians were defined as those whose ancestry originated from the Indian subcontinent. For each patient, presence of modifiable risk factors was documented and calculation of QRISK2 score made as a prediction algorithm for CVD. Statistical analysis was performed using chi-squared testing for categorical variables and Mann-Whitney U test for non-parametric, discrete data. Statistical significance was defined by p-values <0.05.
Results: 959 patients were suitable for inclusion (44% Asian [424/959] vs 56% Caucasian [535/959]). 29% (123/424) of Asians were current smokers compared with 36% (194/535) of Caucasians; p=0.02. 36% (154/424) of Asians and 34% (181/535) of Caucasians had raised body mass index (BMI); p=0.6447. Systolic (148 vs 145; p=0.08) and diastolic (72 vs 71; p=0.12) blood pressure were comparable. Mean QRISK2 score was 20.14% in Asians, compared with 18.09% in Caucasians; p=0.61. 26% (110/424) of Asians compared to 14% (75/535) of Caucasians were not on appropriate statin therapy, advocated for a QRISK2 score >10% based on UK NICE guidelines; p=0.01. This correlated with higher discontinuation rates (14% vs 9%; p=0.05).
Conclusions: This single-centre study provides a real-world perspective of variations between Caucasian and South Asian subpopulations. Profiles for traditional risk factors were broadly comparable. Interestingly, whilst the mean QRISK2 scores suggest that patients presenting with “chest pain” are at high risk of future CVD, compliance with national guidelines for initiation of statin therapy is broadly suboptimal. This disparity appears most marked amongst Asian patients, with cultural and language barriers potentially implicated. Based on findings, we advocate the need for better awareness of primary prevention guidelines amongst clinicians in addition to larger, multi-centre trials to explore trends further.