Point of care testing is appropriate for National Health Service health check

Abstract

Background: The Department of Health launched a cardiovascular disease risk assessment initiative with particular reference to reducing health inequalities in ethnic minorities. Collaboration between HEART UK, Royal Free Hampstead NHS Trust and Hindu Temples resulted in vascular screening in North London. Methods: Subjects of South Asian origin were screened. A full lipid profile and glucose were measured using a point of care testing (POCT) Cholestech LDX analyser (LDX). Venous samples were analysed in our hospital laboratory. Results: The results (215 men; 191 women) were divided into tertiles and Bland-Altman plots were used to assess agreement. At high-density lipoprotein cholesterol (HDL-C) concentrations <1.0 mmol/L the LDX underestimated values by -0.2 mmol/L (P<0.0001). At HDL-C concentrations >1.3 mmol/L this bias disappeared. For total cholesterol the concentration-dependent negative bias was evident at concentrations of <4.1 mmol/L (P < 0.0001). This bias was less evident at higher concentrations. A similar pattern was seen for low-density lipoprotein cholesterol. There were also small variations in glucose and triglyceride values. However, there was excellent agreement in calculated cardiovascular disease risk using kappa analysis for JBS2, QRISK2, ETHRISK and Framingham (κ = 0.86, 0.92, 0.94 and 0.88, respectively). This was a high-risk population since 9.7-19.4% had a ≥20% 10-y probability of a vascular event depending on the risk engine and assay method used. The corresponding values for intermediate risk (11-19%) were 18.6-25.7%. Conclusions: There was a minimum mismatch irrespective of the type of risk calculator used. POCT measurements are adequate for the National Health Service Health Check.