Statins are recommended for the secondary prevention of cardiovascular disease in all patients with chronic kidney disease. But the case for statins in primary prevention is much less certain, as Andrew Connor and Charlie Tomson point out, and doctors should come clean with patients about this uncertainty (doi:10.1136/bmj.b2949). The direction of causality between chronic kidney disease and cardiovascular disease remains unknown, many risk scores exclude patients with kidney disease, and cofactors such as malnutrition and inflammation may exacerbate the risk. Until the ongoing Study of Heart and Renal Protection (SHARP) reports, there’s too little evidence to extrapolate the …