Relationship between body weight and total leukocyte count in morbid obesity

The authors studied the relationship between total leukocyte count and body weight in 42 morbidly obese patients (weight range, 101.5-206.8 kg). None of the patients had a recent history of infection, hematologic disorders, chronic respiratory disease, or were smoking more than 5 cigarettes/day. The range of total leukocyte count was 4.2-12.0 X 10(9) cells/L. Twelve of the 42 patients had a leukocyte count of 10 X 10(9) cells/L. There was a significant correlation between body weight (kg) and total leukocyte count (r = 0.68, P less than 0.001). Morbid obesity should be considered as one of the causes of physiologic leukocytosis.