ESR stands for erythrocyte sedimentation rate, which is a non-specific blood test that measures how quickly red blood cells settle in a tube of blood over a certain period of time. A high ESR value generally indicates the presence of inflammation in the body, but it does not provide information about the cause or location of the inflammation.
An ESR value of 40 mm/hour (millimeters per hour) is considered high for men over 50 years old, and for women over 20 years old. However, the normal range can vary depending on the age, sex, and other factors of the individual. In general, an ESR value of 40 suggests the presence of some degree of inflammation in the body. However, a high ESR value by itself is not enough to make a diagnosis of a specific condition, and further testing may be needed to determine the cause of the inflammation.