Would it be good to follow your doctor's advice? Seemingly, not so much:
In many countries, there is enthusiasm for 'healthy heart programmes' that use counselling and educational methods to encourage people to reduce their risks for developing heart disease. These risk factors include high cholesterol, excessive salt intake, high blood pressure, excess weight, a high-fat diet, smoking, diabetes and a sedentary lifestyle. This review is an update of all relevant randomised trials that have evaluated an intervention that aimed to reduce more than one risk factor (multiple risk factor intervention) in people without evidence of cardiovascular disease. The findings are from 55 trials of between six months and 12 years duration conducted in several countries over the course of four decades. The median duration of follow up was 12 months (with a range of six months to 12 years). Multiple risk factor intervention does result in small reductions in risk factors including blood pressure, cholesterol and smoking. Contrary to expectations, multiple risk factor interventions had little or no impact on the risk of coronary heart disease mortality or morbidity. This could be because these small risk factor changes were not maintained in the long term. Alternatively, the small reductions in risk factors may be caused by biases in some of the studies. The methods of attempting behaviour change in the general population are limited and do not appear to be effective. Different approaches to behaviour change are needed and should be tested empirically before being widely promoted, particularly in developing countries where cardiovascular disease rates are rising. Further trials may be warranted. http://www2.cochrane.org/reviews/en/ab001561.html
In other words, the patients did to some degree what they were told, and their "risk factors" were lowered, but they didn't live any longer. There's some speculation about why that might be the case, but it might be because the advice is based on unsound data about why folks get sick.
Interesting report from the same group, which amounts to a decidedly guarded recommendation about statins:
Cardiovascular disease (CVD) is ranked as the number one cause of mortality and is a major cause of morbidity world wide. Reducing high blood cholesterol which is a risk factor for CVD events is an important goal of medical treatment. Statins are the first-choice agents. Since the early statin trials were reported, several reviews of the effects of statins have been published highlighting their benefits particularly in people with a past history of CVD. However for people without a past history of CVD (primary prevention), the evidence is less clear. The aim of this systematic review is to assess the effects, both in terms of benefits and harms of statins for the primary prevention of CVD. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE until 2007. We found 14 randomised control trials with 16 trial arms (34,272 patients) dating from 1994 to 2006. All were randomised control trials comparing statins with usual care or placebo. Duration of treatment was minimum one year and with follow up of a minimum of six months. All cause mortality. coronary heart disease and stroke events were reduced with the use of statins as was the need for revascularisations. Statin treatment reduced blood cholesterol. Taking statins did not increase the risk of adverse effects such as cancer. and few trials reported on costs or quality of life. This current systematic review highlights the shortcomings in the published trials and we recommend that caution should be taken in prescribing statins for primary prevention among people at low cardiovascular risk. http://onlinelibrary.wiley.com/o/cochrane/clsysrev/articles/CD004816/frame.html
That last bit is a heck of a finishing statement - in other words, they're not really sure you can trust the data sources. I think they might be "onto something."
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