Cardiovascular risk prediction: balancing complexity against simple practicality.

significant decline in cardiovascular mortality and morbidity has been achieved with the improvements in detection and prevention programmes for major risk factors (such as smoking, low physical activity levels, obesity, and high blood pressure) related to cardiovascular disease (CVD). However, CVD still remains the leading cause of mortality and disability in the world. Collectively, ischaemic heart disease and stroke were the cause of 12.9 million deaths in 2010, increasing from one in five to one in four deaths worldwide during two decades. 3 Therefore, prophylaxis strategies are essential for CVD management in terms of both primary and secondary prevention. Given the large body of evidence linking dyslipidaemia, particularly increased LDL cholesterol levels with the CVD development, progression, and prognosis, pharmacological therapy, that is statins, are now the mainstay of CVD prevention. 4 Established CVD puts patients at high risk of future adverse events and they have to undergo appropriate lifestyle interventions and pharmacological treatments (that is, secondary prevention), but no further CVD risk assessment is required. However, risk prediction in patients without known CVD (that is, primary prevention) and particularly decision making with respect to initiation of statin therapy has largely been challenging. Substantial evidence has emerged that allows wider use of statins for primary prevention despite the data being less robust compared to its use for secondary prevention. A recent Cochrane systematic review on statins for the primary prevention of CVD, which included 18 randomised clinical trials with a total number of participants of 56 934, found that statins reduced all-cause mortality (odds ratio [OR] = 0.86, 95% confidence interval [CI] = 0.79 to 0.94); combined fatal and non-fatal CVD (relative risk [RR] 0.75, 95% CI = 0.70 to 0.81); combined fatal and non-fatal coronary events (RR 0.73, 95% CI = 0.67 to 0.80); combined fatal and non-fatal stroke (RR 0.78, 95% = CI 0.68 = 0.89); and revascularisation rates (RR 0.62, 95% CI = 0.54 to 0.72). Of note, the reduction in adverse events appeared to be cost-effective. Also, benefits of treatment outweighed possible hazards caused by statins; indeed, apart from type 2 diabetes mellitus (RR 1.18, 95% CI = 1.01 to 1.39), the risk of other possible complications (for example, cancer, myalgia, rhabdomyolysis, liver enzyme elevations, renal dysfunction, or arthritis) did not differ between patients on statins and those on placebo (overall RR 1.00, 95% CI = 0.97 to 1.03). 5 These findings are in line with …