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BACK TO BACKvariable, with some left with profound disability.A significant proportion of people with coronaryheart disease progress to congestive heart failurewhere QoL, as measured by symptom burden,depression, and spiritual well-being, is akin tothat of people with advanced cancers. 3‘And in the end it’s not the years in your life thatcount. It’s the life in your years.’—Abraham LincolnProspective cohorts about late-life function andsurvival to 90 or 100 years, 4,5 show that CVDrisk factors mirror longevity. Furthermore, thosewith healthy behaviours and lower CVD riskfactors at age 70 years are likely to have betterlate-life physical function, mental well-being andlower incidence of chronic diseases. If they dodevelop a chronic disease, the onset is typicallythree to five years later. 5How applicable are CVDrisk prediction tools?CVD risk is typically presented as the predictedprobability of having a symptomatic CVD eventduring a subsequent time period and is derivedfrom cohort studies that estimate the combinedeffect of multiple risk factors on event rates. Ofall the risk factors, age is not surprisingly themost powerful predictor of a future CVD event,because age is a proxy for the amount of exposureto the combined known and unknown risk factors.CVD risk prediction tools used in New Zealandare based on the Framingham Heart Study whichonly investigated people between 30 and 74years of age. A recent study has questioned thevalidity of the Framingham equation for thoseover 85 years, but the cohort was very small (250participants) and the authors conclude that theirfindings require validation in a separate cohort. 6As the accuracy of CVD risk prediction over 75years is not well studied, New Zealand guidelinesrecommend risk assessing a person over 75years as if they were 75 years. This will delivera conservative estimate of their five-year CVDprognosis, so if older patients are estimated tohave a CVD risk over 15% in five years they willalmost certainly have been correctly classified asbeing at high absolute risk.Erratum—Clarification about citation of Back to Back debates.It has been brought to my attention that both authors may be includedin a joint citation, for example ‘Marks R, Potter JD. New Zealand shouldhave mandatory fortification of bread with folic acid. J Prim Health Care.2010;2:74–8.’ This is confusing because it appears as though the authorarguing against a moot actually supports it. All Back to Back articles shouldtherefore be cited separately, as in:Marks R. New Zealand should have mandatory fortification of bread withfolic acid—the ‘yes’ case. J Prim Health Care. 2010;2:74–5.Potter JD. New Zealand should have mandatory fortification of bread withfolic acid—the ‘no’ case. J Prim Health Care. 2010;2:76–8.—The EditorThe greater the short-term absolute CVD risk,the greater the short-term benefit of interventionsthat lower risk factors. Hence most CVDguidelines recommend management to be basedon short-term absolute risk. While lifestyleadvice on a healthy heart diet, smoking cessationand physical activity are key recommendations forall, our current guidelines recommend commencingstatin therapy for those estimated to be >15%five-year CVD risk.What is the evidence forstatin benefit vs harm?The Cholesterol Treatment Trialists’ Collaborationwas an enormous meta-analysis of 90 056individuals who participated in randomised trialsof statin treatment. 7 They demonstrated a 12%proportional reduction in all-cause mortality permmol/L reduction in LDL cholesterol. Benefitsfrom treatment were significant within the firstyear of treatment and increased in subsequentyears. After five years of follow-up, they demonstrateda 21% decrease in any major vascularevent (including 23% reduced risk of heartattacks and 17% reduced risk of stroke). Thismeta-analysis included five trials that includedparticipants over 75 years. They found that therewas nothing magic about age that makes drugswork differently—the proportional reductionswere about the same.In terms of major harms, rhabdomyolysis wasexceedingly rare 9/39 884 patients (0.023%) onVOLUME 2 • NUMBER 4 • DECEMBER 2010 J OURNAL OF PRIMARY HEALTH CARE 331