Change in absolute neutrophil count after COVID-19 infection in patients using clozapine versus other antipsychotics

Abstract

It was reported that patients who contracted COVID-19 while taking clozapine exhibited a distinct hematological response. However, the absence of control groups made it difficult to attribute it to clozapine. The changes in absolute neutrophil counts (ANCs) during the 4 weeks after COVID-19 infection were compared between the two groups of patients with severe mental illnesses (SMIs) (49 patients using clozapine and 54 using other antipsychotics) using generalized additive modeling. Although the pattern of a transient drop in ANC followed by gradual recovery could be demonstrated in both groups, it was more pronounced in the clozapine group (P = 0.00025). Nevertheless, overall ANC remained at a higher level in the clozapine group. The results suggested potential interaction between clozapine and COVID-19 at the level of hematological dynamics. However, it did not necessarily indicate that such interaction is inevitably harmful or dangerous. It was more of a concern that some patients using other antipsychotics exhibited decreased ANC, which did not easily recover. Traditionally, clinicians have been concerned about the worsening of hematological side effects in clozapine patients after COVID-19 infection. However, the obtained result highlighted the necessity of hematological monitoring in patients using any type of antipsychotics for SMIs.

Stroke, COVID-19, and other somatic aspects of psychiatric disorders treatments

“…In this issue, two papers report data on the impact of COVID-19 infection in psychoses treatment and obsessive-compulsive symptoms. Following the abovementioned immunological component of psychiatric disorder and their treatment, the paper in this issue reports on the immunological aspects of COVID-19 infection on neutrophil count in patients using clozapine versus other antipsychotics (Jeong et al, 2024). Results suggest a possible detrimental synergic effect on reducing neutrophil count by both COVID-19 infection and clozapine, which is less evident when other antipsychotics are used.…”