Neutrophil-lymphocyte Ratio and C-reactive Protein Level in Patients with Major Depressive Disorder Before and After Pharmacotherapy

In Adhikari et al., at baseline males and females did not differ in any blood parameters, except for a higher total white blood cell count in males.

“Baseline: males and females do not differ in any blood parameters, except for a higher total white blood cell count in males”

In Adhikari et al., in males, NLR was associated with decreased depressive symptoms and suicide risk, and higher CRP.

“In males, NLR was associated with decreased depressive symptoms and suicide risk, and higher CRP”

In Adhikari et al., after 12 weeks of pharmacotherapy, in females only, neutrophils were increased, lymphocytes decreased, and consequently NLR was increased in response to antidepressant therapy.

“After pharmacotherapy (12 weeks), in females only, neutrophils were increased, lymphocytes decreased and consequently, NLR was increased in response to antidepressant therapy”

Five included studies were conducted in Turkey, one in India, two in Spain, one in Sweden, one in Israel, and one in Thailand.

“Five studies were conducted in Turkey [8, 20, 30–32], one in India [27], two in Spain [4, 29], one in Sweden [28], one in Israel [26], and one in Thailand [9].”

Inflammatory response is influenced by multiple factors, such as body mass index, use of tobacco and other psychoactive substances, duration and severity of illness, resistance to antidepressant treatment, other psychiatric comorbidities, unbalanced diet, lack of exercise, and stress or traumatic life events in childhood or adulthood.

“However, we also need to keep in mind that inflammatory response is influenced by multiple factors, such as body mass index, use of tobacco and other psychoactive substances, duration and severity of illness, resistance to antidepressant treatment, other psychiatric comorbidities, unbalanced diet, lack of exercise, and stress or traumatic life events in childhood or adulthood [27, 29, 39].”

Adhikari et al. found a significant increase in NLR after 12 weeks of antidepressant treatment only in females, in a sample of 50 depressed patients without antidepressant treatment the previous month.

“However, in a sample of 50 depressed patients without antidepressant treatment the previous month, Adhikari et al. [27] found a significant increase in NLR after 12 weeks of antidepressant treatment only in females [NLR mean in females (SD) = 2.55 (0.87) pretreatment vs 2.85 (0.89) 12 weeks after treatment; p < 0.001].”

Not all depressed patients show changes in the inflammatory response.

“These results may indicate that: (i) not all depressed patients show changes in the inflammatory response [27];”