Restrictive type and infectious complications might predict nadir hematological values among individuals with anorexia nervosa during the refeeding period: a retrospective study

J Eat Disord. 2022 May 5;10(1):64. doi: 10.1186/s40337-022-00586-x.

Abstract

Background: Although hematological abnormalities in patients with anorexia nervosa have been documented, the mechanisms involved have not been fully clarified, especially during the refeeding period when hematological values further decrease after admission prior to improving. Here we address potential mechanisms underlying the hematological abnormalities of inpatients with anorexia nervosa during the refeeding period.

Methods: We recruited patients from 101 admissions corresponding to 55 individual patients with anorexia nervosa with severe malnutrition (body mass index, 13.4 ± 3.4) from the neuropsychiatry unit in Ashikaga Red Cross Hospital during the period from October 1999 to March 2018. We analyzed three hematological cell measures, i.e., hemoglobin, white cell count, and platelet count, to determine their levels at admission and their lowest levels during the refeeding period and calculated the percent decrease in those values from admission to the nadir levels. We analyzed each measure using a general mixed model with explanatory variables, including data upon admission and a treatment-related indicator, i.e., energy intake.

Results: The initial hemoglobin value of 12.1 ± 2.7 g/dl decreased by 22.3% to 9.4 ± 2.5 g/dl; the initial white cell count was 5387 ± 3474/μl, which decreased by 33.6% to 3576 ± 1440/μl; the initial platelet count of 226 ± 101 × 103/μl decreased by 24.3% to 171 ± 80 × 103/μl. All nadir levels were observed during the refeeding period from the fifth to tenth day of hospitalization. Significant correlations among the three hematological cell measures, particularly at the nadir levels, were found. Of note, 41.7% of our patients who received red blood cell transfusion during hospitalization showed normal hemoglobin levels upon admission. The anorexia nervosa restrictive type was associated with a lower nadir level of white blood cell count. Infectious complications were related to a lower nadir level of hemoglobin and a greater percent decrease in hemoglobin level as well as to the need for red blood cell transfusion.

Conclusions: Nadir hematological cell measures of inpatients with anorexia nervosa might be predicted by the restrictive type and infectious complications. The anorexia nervosa restrictive type was associated with further decrease in hematological values during the refeeding period.

Keywords: Anemia; Anorexia nervosa; Infection; Leukopenia; Pancytopenia; Restrictive type; Thrombocytopenia.

Plain language summary

Deficiencies in components of the blood, such as a low red blood cell count, low white blood cell count, and low platelet numbers, are observed frequently in patients with anorexia nervosa, particularly those with severe malnutrition, and these deficiencies become manifest after hospitalization during the initial period when patients are reintroduced to food. Why this deterioration occurs even under medical care is not well understood. Here we analyzed the patient factors associated with these blood cell abnormalities. Patients with the restrictive type of anorexia nervosa, and infectious complications were more likely to have the lowest levels of hematological values during the refeeding period.