Colorectal Risk and Statins
About Statins
Statins are a class of drugs used to lower blood cholesterol. They work in your liver to block a substance needed to make cholesterol. They may also help your body reabsorb cholesterol that has accumulated in plaques on your artery walls. This helps prevent further blockage in your blood vessels. Long-term use of statins may even reduce existing blockage in narrowed blood vessels.
In Canada, these medications include atorvastatin (Lipitor®), fluvastatin (Lescol® and Lescol XL®), lovastatin (Mevacor®), pravastatin (Pravachol®), rosuvastatin (Crestor®), and simvastatin (Zocor®).
Avoid taking statins with grapefruit juice, which alters your body’s metabolism of these drugs. Doctors generally recommend that people take statins late in the day because the body makes most of its cholesterol at night. Health Canada issued a warning this year that all patients taking any cholesterol lowering drug are advised to report any unexplained muscle pain, muscle weakness or cramps, general weakness, fever, fatigue, or any brown or discoloured urine to their physician immediately. Asian patients (having Filipino, Chinese, Japanese, Korean, Vietnamese, or South Asian origin) may be at greater risk of developing muscle-related adverse events.
Colorectal Risk
Researchers have long noted a correlation between statin usage and a decreased risk of colon cancer. While past studies have produced mixed results, a population-based case control study from northern Israel between 1998 and 2004, involving 1,953 patients and 2,015 controls, shows good results.
The researchers reported a 47% reduction in the risk of colorectal cancer among long-term statin users (five years or more), as compared with short-term users or non-statin users. This effect was still present after adjustment for other colon cancer reducing factors such as:
- Use of aspirin or other non-steroidal anti-inflammatory drugs (NSAIDs),
- Physical activity level,
- Hypercholesterolemia,
- Family history of colorectal cancer,
- Ethnic group, and
- Level of vegetable consumption.