From the Guidelines
Elevated creatine kinase (CK) levels indicate muscle damage and require prompt medical evaluation, with treatment depending on the underlying cause, such as medication adjustments for statin-induced elevations or corticosteroids for inflammatory conditions, as stated in the 2019 guideline on the management of blood cholesterol 1.
Causes of Elevated CK
The causes of elevated CK levels include:
- Intense exercise
- Muscle trauma
- Medications, particularly statins like atorvastatin or simvastatin
- Inflammatory muscle diseases
- Certain genetic disorders
Evaluation and Treatment
If you have elevated CK, it is recommended to:
- Discontinue strenuous exercise for 3-5 days before retesting
- Inform your doctor about all medications you're taking
- Monitor mild elevations (less than 5 times normal) without symptoms
- Seek immediate medical attention for significant elevations with muscle pain, weakness, or dark urine to prevent kidney damage Staying hydrated is important as it helps protect the kidneys from damage caused by muscle breakdown products, as discussed in the context of acute kidney injury and chronic kidney disease 1.
Statin-Associated Muscle Symptoms
Statin-associated muscle symptoms (SAMS) are common, with myalgias (CK normal) occurring in 1% to 5% of patients in randomized controlled trials (RCTs) and 5% to 10% in observational studies, as reported in the 2019 guideline 1.
Rare but Serious Side Effects
Rare but serious side effects of statins include myositis, myopathy, and rhabdomyolysis, which require prompt medical attention, as highlighted in the 2002 clinical advisory on the use and safety of statins 1.
Monitoring and Prevention
Regular monitoring of renal function and adjustment of prescribed drugs can help prevent kidney damage and worsening renal function, as discussed in the context of heart failure and chronic kidney disease 1.
From the Research
Elevated Creative Kinase
Elevated creative kinase (CK) levels can be an indicator of various health issues, including myocardial infarction and muscle damage.
- The level of CK-MB, a specific isoenzyme of CK, can help differentiate between myocardial injury and muscle damage 2.
- A study published in 1997 found that patients with a history of chronic angina pectoris or hypertension had no influence on CK-MBm/CK levels, but treatment with beta-blockers before infarction resulted in lower relative CK-MBm peak values 3.
- Another study published in 1986 proposed a CK-MB/total CK ratio of 80 ng/U as the cutoff value for differentiating myocardial necrosis from muscular injury 2.
- Elevated CK-MB with normal CK has been found to predict worse outcomes in patients with acute coronary syndromes, with a 25% to 49% increased relative risk of worse outcomes 4.
Diagnosis and Treatment
- The CK-MB isoform ratio can be increased in both acute skeletal muscle injury and myocardial infarction, making it a useful tool for distinguishing between recent and old injury 5.
- A study published in 2018 explored the therapeutic potential of augmenting the CK energy shuttle to ameliorate myocardial ischaemia-reperfusion injury, highlighting the need for further research in this area 6.
- Patients with elevated CK-MB should receive aggressive management commensurate with their increased risks, and CK-MB measurement should be used to search for cardiac ischemia in all patients with acute coronary syndromes 4.