Sunday, November 20, 2005
High doses of the cholesterol-lowering drug Lipitor were no better at preventing recurrent heart attacks and heart-related deaths than regular doses of the competing drug Zocor, according to the latest study on efforts to aggressively treat heart conditions.
The study, funded and conducted by Lipitor's maker Pfizer Inc., was prepared for presentation Tuesday at an American Heart Association meeting in Dallas. It also appears in Wednesday's Journal of the American Medical Association.
...The latest study involved 8,888 mostly male Scandinavian patients aged 61 on average who had previous heart attacks and were given either a high dose of Lipitor or a standard dose of Merck's Zocor.
The researchers didn't find the main difference they were looking for - fewer "major coronary events" in the Lipitor group during an average follow-up of almost five years. That category lumped together cardiovascular deaths, nonfatal heart attacks and nonfatal cardiac arrest. These events totaled 463 in the Zocor patients and 411 in the Lipitor patients, a difference that was not statistically significant.
For the past year, the cholesterol mantra has been to push the LDL cholesterol below 70 for patients who are known to have diseased coronary arteries. The recommendations were somewhat controversial - having been made by a panel of doctors who had ties to the statin industry - but they were widely adopted, anyways. The LDL cholesterol is the form of cholesterol that is most closely associated with heart disease, though its relationship with heart disease is probably more nuanced than we currently admit.
The study does seem to call the mantra into question. Even though the high dose Lipitor did lower the LDL more than the Zocor, the final results were about the same:
There were 178 coronary deaths (4.0%) in the simvastatin [Zocor - ed.] group vs 175 (3.9%) in the atorvastatin [Lipitor-ed.] group.... Nonfatal myocardial infarction occurred in 321 patients (7.2%) in the simvastatin group and in 267 (6.0%) in the atorvastatin group.
Lipitor did have an advantage when it came to preventing strokes, but for some reason, neurologists don't promote statins with the same enthusiasm as cardiologists. Maybe that will change, though.
Interestingly, people were less tolerant of Lipitor. They were more likely to experience muscle aches and liver enzyme elevations. And they were more likely to stop taking it:
Overall adherence, defined as total study medication exposure as a percentage of total follow-up time, was 89% in the atorvastatin group and 95% in the simvastatin group. By the end of the study, 14% of the atorvastatin-allocated and 7% of the simvastatin-allocated patients had permanently discontinued study medication.
Maybe we need to rethink those guidelines. Now, will anyone sing Pfizer's praises for paying for - and publishing a study that cast its competitor in a better light?
*Incremental Decrease in End Points Through Aggressive Lipid Lowering
posted by Sydney on 11/20/2005 07:31:00 AM 0 comments