5. Creatinine levels relate to both muscle mass and to kidney function. As you age, your muscle mass decreases but your kidneys tend to function less effectively. The net result is not much change in creatinine levels in the blood as you get older. ^ Back to top.
https://labtestsonline.org/understanding/analytes/creatinine/tab/faq
A creatinine blood test measures the level of creatinine in the blood. Creatinine is a waste product that forms when creatine breaks down. Creatine is a substance found in muscle. Creatinine levels help determine how well your kidneys function. Your kidneys are responsible for eliminating creatinine from the body when you urinate. When creatinine levels increase, your kidney function may be impaired.
http://www.healthline.com/health/creatinine-blood
A patient with a greater muscle mass will have a higher creatinine level. While a baseline serum creatinine of 2.0 mg/dL (150 μmol/L) may indicate normal kidney function in a male body builder, a serum creatinine of 1.6 mg/dL (110 μmol/L) can indicate significant renal disease in an elderly female.
https://en.wikipedia.org/wiki/Creatinine
Serum creatinine (a blood measurement) is an important indicator of renal health because it is an easily measured byproduct of muscle metabolism that is excreted unchanged by the kidneys.
https://en.wikipedia.org/wiki/Creatinine
One mg/dL of creatinine is 88.4 μmol/L. The typical human reference ranges for serum creatinine are 0.5 to 1.0 mg/dL (about 45-90 μmol/L) for women and 0.7 to 1.2 mg/dL (60-110 μmol/L) for men. The significance of a single creatinine value must be interpreted in light of the patient's muscle mass.
https://en.wikipedia.org/wiki/Creatinine
Creatinine levels that reach 2.0 or more in babies and 10.0 or more in adults may indicate severe kidney impairment and the need for a dialysis machine to remove wastes from the blood. Continue Reading.
http://www.medicinenet.com/creatinine_blood_test/page2.htm
Measuring serum creatinine is a simple test, and it is the most commonly used indicator of renal function. A rise in blood creatinine level is a late marker, observed only with marked damage to functioning nephrons.
https://en.wikipedia.org/wiki/Creatinine
Creatine is a compound that is made primarily in the liver and then transported to your muscles, where it is used as an energy source for muscle activity. Once in the muscle, some of the creatine is spontaneously converted to creatinine. The amount of both creatine and creatinine depend on muscle mass, so men usually have higher levels than women. Creatine is now available as a dietary supplement.
https://labtestsonline.org/understanding/analytes/creatinine/tab/faq
Normal levels of creatinine in the blood are approximately 0.6 to 1.2 milligrams (mg) per deciliter (dL) in adult males and 0.5 to 1.1 milligrams per deciliter in adult females.
http://www.medicinenet.com/creatinine_blood_test/page2.htm
Elderly persons, on the other hand, may have less creatinine in their blood than the norm. Infants have normal levels of about 0.2 or more, depending on their muscle development. In people with malnutrition, severe weight loss, and long standing illnesses, the muscle mass tends to diminish over time and, therefore, their creatinine level may be lower than expected for their age.
http://www.medicinenet.com/creatinine_blood_test/page2.htm
what is creatine serum
A creatine serum is an important indicator of renal health because it is an easily measured byproduct of muscle metabolism that is excreted unchanged by the kidneys. Creatine serum is an important indicator of renal health .