ESR (Erythrocyte Sedimentation Rate)

What is ESR?

ESR (erythrocyte sedimentation rate) measures how quickly red blood cells settle to the bottom of a test tube over one hour. When inflammation is present, proteins in the blood cause red blood cells to clump together and fall faster.

ESR is a nonspecific marker — it tells you inflammation exists somewhere but not where or why. It's often used alongside CRP for a more complete picture.

Normal Ranges

Group	ESR
Men under 50	0–15 mm/hr
Men over 50	0–20 mm/hr
Women under 50	0–20 mm/hr
Women over 50	0–30 mm/hr

ESR naturally increases with age.

Why It Matters

Inflammation Detection

ESR rises in response to inflammation from any cause: infection, autoimmune disease, tissue injury, or malignancy.

Disease Monitoring

For conditions like rheumatoid arthritis or polymyalgia rheumatica, tracking ESR helps monitor disease activity and treatment response.

Cancer Screening

Persistently elevated ESR without obvious cause may warrant investigation for underlying malignancy.

ESR vs. CRP

Both measure inflammation, but differently:

CRP rises and falls quickly (hours)
ESR changes more slowly (days to weeks)

CRP is better for acute changes; ESR may be better for chronic conditions.

What Raises ESR

Infections
Autoimmune diseases
Cancer
Anemia
Pregnancy
Kidney disease
Advanced age