The Experimental Pain Experienced in a Cold Pressor Task Is Influenced by Hemoglobin Levels in Young Adult Females

The intensity of pain perceived for the same noxious stimulus is different in different persons, depending on the biological, psychological, and social factors related to the individual. In clinical practice, it is important to know the factors influencing pain perception. The presence of anemia may affect pain perception.

This study was conducted on 73 female subjects of whom 25 were non-anemic, 24 had mild, and 24 had moderate anemia. Experimental pain was produced by cold pressor task (CPT). Pain response was evaluated in terms of cardiovascular reactivity (CVR - changes in blood pressure and heart rate), and pain sensitivity (PS - pain threshold, pain tolerance, and pain rating).

Anemic subjects showed higher CVR to stress. The average increase in systolic blood pressure was 5.28 mm of Hg in non-anemic, compared to 3.25 in mildly anemic and 9.00 mm of Hg in moderately anemic subjects. The average increase in diastolic blood pressure was 2.24 mm of Hg in non-anemic, 2.5 in mildly anemic, and 4.83 mm of Hg in moderately anemic subjects. The average increase in heart rate was 2.88 beats per minute (bpm) in non-anemic, 4.83 in mildly anemic, and 7 bpm in moderately anemic subjects. Pain rating was higher in anemic subjects (average 7.21) compared to the non-anemic subjects (average 6.44).

CPT-induced pain causes greater cardiovascular reactivity in anemic patients. The average pain rating is higher in anemic subjects.