Association between neutrophil to lymphocyte ratio and depressive symptoms among Chinese adults: A population study from the TCLSIH cohort study

Neutrophil-to-lymphocyte ratio as a predictive biomarker for early diagnosis of depression: A narrative review

Depression is a mood disorder that causes persistent feelings of sadness, hopelessness, loss of interest, and decreased energy. Early diagnosis of depression can improve its negative impacts and be effective in its treatment. Previous studies have indicated that inflammation plays an important role in the initiation and development of depression, hence, various inflammatory biomarkers have been investigated for early diagnosis of depression, the most popular of which are blood biomarkers. The Neutrophil to lymphocyte ratio (NLR) may be more informative in the early diagnosis of depression than other widely used markers, such as other leukocyte characteristics or interleukins. Considering the importance of early diagnosis of depression and the role of NLR in early diagnosis of depression, our paper reviews the literature on NLR as a diagnostic biomarker of depression, which may be effective in its treatment. Various studies have shown that elevated NLR is associated with depression, suggesting that NLR may be a valuable, reproducible, easily accessible, and cost-effective method for the evaluation of depression and it may be used in outpatient clinic settings. Closer follow-up can be performed for these patients who have higher NLR levels. However, it seems that further studies on larger samples, taking into account important confounding factors, and assessing them together with other inflammatory markers are necessary to draw some conclusive statements.

Neutrophil to lymphocyte ratio and antidepressant treatment response in patients with major depressive disorder: Effect of sex and hippocampal volume

Several factors may affect response to treatment in Major Depressive Disorder (MDD) including immune/inflammatory alterations and regional brain volumes, particularly in hippocampal regions which have shown to be influenced by inflammatory status. Neutrophil-to-lymphocyte ratio (NLR) is an inflammatory marker found to be elevated in depressed women in large population studies. Here we investigate the effect of NLR on treatment response in MDD patients, and the role of sex and hippocampal volume on influencing this relationship. A sample of 124 MDD depressed inpatients (F = 80) underwent MRI acquisition, admission NLR was calculated by dividing absolute neutrophil by absolute lymphocyte counts and depression severity was assessed at admission and discharge via the Hamilton Depression Rating Scale (HDRS). As a measure of treatment response, delta HDRS was calculated. We found a significant moderation effect of sex on the relationship between NLR and Delta HDRS: a negative relation was found in females and a positive one in males. NLR was found to negatively affect hippocampal volumes in females. Both left and right hippocampal volume positively associated with Delta HDRS. Finally, left hippocampal volume mediated the effect of NLR on Delta HDRS in females. Sex moderated the relation between inflammation and treatment response in line with previous reports linking inflammation to hampered antidepressant effect in females. Further, this effect is partially mediated by hippocampal volume, suggesting that antidepressant response may be hampered by the detrimental effect of inflammation on the brain.

Associations between sleep disturbance, inflammatory markers and depressive symptoms: Mediation analyses in a large NHANES community sample

Both depression and sleep disturbance have been linked to inflammation. However, the role that inflammation plays in the relationship between sleep disturbance and depression remains unclear. We examined pairwise associations between inflammatory markers (neutrophil-to-lymphocyte ratio [NLR] and C-reactive protein level [CRP]), sleep disturbance, and depressive symptoms in a robust, ethnically diverse sample (n = 32,749) from the National Health and Nutrition Examination Survey (NHANES). We found higher levels of inflammatory markers in participants with depression and/or sleep disturbance compared to those without depression or sleep disturbance. Sleep disturbance was positively associated with inflammatory markers and depressive symptoms even after considering a wide range of potential confounders (e.g., age, sex, body mass index). Inflammatory marker levels were nonlinearly associated with depressive symptoms and were positively associated with depressive symptoms after reaching the inflection point (NLR, 1.67; CRP, 0.22 mg/dL). Inflammatory markers mediated a marginal portion (NLR, 0.0362%, p = 0.026; CRP, 0.0678%; p = 0.018) of the potential effects of sleep disturbance on depressive symptoms. Our research showed that inflammatory markers, sleep disturbance, and depression are pairwise correlated. Increased inflammatory markers levels slightly mediate the association between sleep disturbance and depression.

Association between neutrophil-lymphocyte ratio and perinatal depressive symptoms among Chinese women

OBJECTIVE

The prevalence of depression has increased dramatically in the past few decades, and pregnant women are at high risk for depression. It is widely thought that inflammation plays a critical role in the pathogenesis of depression. Therefore, we aimed to evaluate the association between the neutrophil-lymphocyte ratio (NLR), a marker of chronic immune inflammation, and perinatal depressive symptoms.

METHODS

A cohort study involving 535 pregnant women was conducted based on a prospective birth cohort in Wuhan, China. The Edinburgh Postnatal Depression Scale (EPDS) was used to assess antepartum depression (APD) and postpartum depression (PPD) during the second trimester of pregnancy and one month after delivery. The NLR during the second trimester was determined based on a routine blood test. The association between NLR and depressive symptoms was evaluated using logistic regression analysis and restricted cubic spline (RCS) regression.

RESULTS

We found that the prevalence of APD and PPD was 8.4% and 15.1%, respectively. NLR levels were positively associated with APD (OR = 1.52, 95% CI: 1.20--1.91). After adjusting for potential confounders, the OR (95% CI) of APD for the highest NLR quartile was 4.56 (1.58, 13.13) compared with the lowest quartile. No significant association was found between NLR and PPD. RCS regression model analysis indicated a linear correlation between NLR and APD (P for non-linearity = 0.58).

CONCLUSION

Overall, elevated mid-trimester NLR is independently associated with APD but not PPD.

Association between neutrophil to lymphocyte ratio and depression among US adults: From a large population-based cross-sectional study

OBJECTIVE

The study aims to determine the association between neutrophil to lymphocyte ratio (NLR) and depression and severity.

METHODS

We conducted a cross-sectional analysis of the National Health and Nutrition Examination Survey (NHANES). The Patient Health Questionnaire (PHQ-9) was administered to assess depression and its severity. NLR was calculated as a neutrophil count-to-lymphocyte count ratio.

RESULTS

The study included 22,207 adults (mean age, 44.43 years; women, 51.05%), and 1671 (6.54%) reported depression. The association between NLR and depression was not significant (odds ratio [OR], 1.06, 95% confidence interval [CI], 0.98 to 1.15, p = 0.12) after fully adjusting the covariates, and similar results (Q1 reference Vs Q2: OR, 0.87, 95%CI, 0.70 to 1.07 Vs Q3: OR, 0.99, 95%CI, 0.80 to 1.21 Vs Q4: OR, 1.08, 95%CI, 0.86 to 1.35, p for trend 0.21) when NLR as a categorical variable. After controlling for all confounding variables, a U-shaped relationship between NLR and depression severity was observed, and the inflection point was 1.78. Subgroup analyses showed a significant association among Mexican American/other Hispanic (OR, 1.13, 95%CI, 1.00 to 1.28, p = 0.04), non-Hispanic blacks (OR, 1.18, 95%CI, 1.07 to 1.32, p = 0.002), the subjects with poverty income ratio above four (OR, 1.24, 95%CI, 1.00 to 1.53, p = 0.048) between NLR and depression. The results from the sensitivity analyses remained stable.

CONCLUSION

The association between NLR and depression is not general across depressed populations among US adults. This association may be specific to subgroups. The relationship between NLR and depression severity is non-linear.

Neutrophil-lymphocyte ratios as inflammatory biomarkers in psychiatric patients

PURPOSE

There is a growing amount of evidence to suggest that inflammation may have a role in the onset and prognosis of psychiatric disorders. We reviewed the literature of studies investigating neutrophil-lymphocyte ratios (NLR), a biomarker of inflammation, in both adult and youth psychiatric populations. The limitations of NLR, in addition to the potential mechanisms underlying its relationship with psychiatric disorders, are also discussed.

RECENT FINDINGS

Unlike in the general population, NLR is elevated in a proportion of adult patients with schizophrenia, major depressive disorder and bipolar disorder, though associations with symptom severity and other clinical parameters are less clear. When compared to baseline, reductions in NLR are sometimes reported after treatment and remission. Results in youth populations largely resemble findings obtained from adult samples, even though youth studies are far fewer in number.

SUMMARY

The consistent findings of elevated NLR across the reviewed psychiatric disorders suggest that abnormal NLR is not specific to any one disorder but may reflect a pathological brain process that leads to brain dysfunction. These findings support hypotheses of neuroinflammation being important to the etiology of psychiatric disorders. More research is needed to further elucidate the relationship between specific diagnostic and behavioural constructs and NLR. Future work is also needed to determine the specific neuroinflammatory mechanisms that give rise to specific disorders.

Ambient particulate air pollution, blood cell parameters, and effect modification by psychosocial stress: Findings from two studies in three major Chinese cities

The associations between particulate matter (PM) exposure, psychosocial stress and blood cell parameters are bringing novel insights to characterize the early damage of multiple diseases. Based on two studies conducted in three Chinses cities using cross-sectional (Beijing, 425 participants) and panel study (Tianjin and Shanghai, 92 participants with 361 repeated measurements) designs, this study explored the associations between short-term exposure to ambient PM and blood cell parameters, and the effect modification by psychosocial stress. Increasing PM_2.5 exposure was significantly associated with decreases in red blood cell (RBC) count and mean corpuscular hemoglobin concentration (MCHC), and increases in mean corpuscular volume (MCV), platelets count (PLT) and platelet hematocrit (PCT) in both studies. For instance, a 10 μg/m³ increment in PM_2.5 concentration was associated with a 1.04% (95%CI: 0.16%, 1.92%) increase in PLT (4-d) and a 1.09% (95%CI: 0.31%, 1.87%) increase in PCT (4-d) in the cross-sectional study, and a 0.64% (95%CI: 0.06%, 1.22%) increase in PLT (1-d) and a 0.72% (95%CI: 0.33%, 1.11%) increase in PCT (1-d) in the panel study, respectively. In addition, stronger increases in MCV, PLT, and PCT associated with PM_2.5 exposure were found in higher psychosocial stress group compared to lower psychosocial stress group (p for interaction <0.10), indicating that blood cell parameters of individuals with higher psychosocial stress might be more susceptible to the early damages of PM_2.5 exposure.

Association between depression or anxiety symptoms and immune-inflammatory characteristics in in-patients with tuberculosis: A cross-sectional study

BACKGROUND

Depression and anxiety are major psychological issues among patients with tuberculosis (TB) owing to chronic and complex treatments, have been reported to be closely correlated with immune and inflammation. However, the association of peripheral immune-inflammatory characteristics with depression/anxiety symptoms in in-patients with TB has rarely been reported.

METHODS

A cross-sectional study of 338 in-patients with TB from 3 hospitals in China were enrolled to investigate their depression and anxiety status by using the nine-item Patient Health Questionnaire (PHQ-9) and seven-item Generalized Anxiety Disorder Scale (GAD-7). Participants were divided into groups based on their PHQ-9 and GAD-7 scores, and differences in demography and immune-inflammatory characteristics were studied. Logistic analysis was performed to explore factors related to depression and anxiety symptoms.

RESULTS

Depression and anxiety prevalence among patients with TB was 47.9 and 42.6%, respectively. Furthermore, 38.5% of patients reported a comorbidity of depression and anxiety symptoms. The counts of CD3, CD4, CD8, and lymphocytes decreased, whereas those of neutrophils, platelets, and peripheral blood cells and their derived indices increased among TB patients with depression or anxiety in comparison with those without symptoms (p < 0.05). In addition, increasing age, lower income (monthly income ≤ 3,000 yuan), divorced or widowed, drug resistance, and higher systemic immune inflammation index (SII) were significantly associated with depression or anxiety symptoms (p < 0.05).

CONCLUSION

Approximately half of the patients with TB suffered from depression or/and anxiety symptoms. Patients with depression or anxiety present worse cell immune status and stronger inflammatory responses compared to those without symptoms. We emphasized the importance of paying attention to the dysfunction of immune-inflammation process of TB patients with depression or anxiety symptoms. Especially, SII has a potential application value in guiding the evaluation of TB-related depression or anxiety owing to its easily accessibility and being economical.

Neutrophil/lymphocyte, platelet/lymphocyte and monocyte/lymphocyte ratios in mood disorders

Major depressive disorder (MDD) and bipolar disorders (BDs), the most severe types of mood disorders (MDs), are considered as among the most disabling illnesses worldwide. Several studies suggested that inflammatory neuroinflammation might be involved in the pathophysiology of MDs, while reporting increasing data on the relationships between these processes and classical neurotransmitters, hypothalamus-pituitary-adrenal axis (HPA), and neurotrophic factors. The assessment of neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR) and monocyte/lymphocyte ratio (MLR) in peripheral blood represents a simple method to evaluate the inflammatory status. The aim of the present paper was to review the literature on the possible relationships between NLR, PLR and MLR in MDs, and to comment on their possible wider use in clinical research. Thirty-five studies were included in the present review. The majority of them higher values of these parameters, particularly NLR values, in patients with MDs, when compared to healthy subjects. The increase would appear more robust in patients with BD during a manic episode, thus indicating that it could be considered as both state and trait markers. In addition, increased NLR and PLR levels seem to represent prognostic elements for the early discovery of post-stroke depression. The findings of the present review would indicate the need to carry our further studies in this field. In particular, NLR, PLR and MLR seem to be promising tools to detect economically and easily the activation of the inflammatory system, and to perhaps evaluate the etiology and course of MDs. Again, they could suggest some information to better understand the relationship between inflammatory and cardiovascular disease and MDs, and thus, to provide clinical implications in terms of management and treatment.

The Association between Neutrophil-to-Lymphocyte Ratio and Diabetic Depression in U.S. Adults with Diabetes: Findings from the 2009-2016 National Health and Nutrition Examination Survey (NHANES)

Objective

To determine the association between neutrophil-to-lymphocyte ratio (NLR) and clinically relevant depressive symptoms in people with diabetes.

Methods

This cross-sectional study was conducted among adults (age >18) with diabetes in the National Health and Nutrition Examination Survey (NHANES) between 2009 and 2016. NLR was calculated from complete blood count. Nine-item Patient Health Questionnaire (PHQ-9) was used to measure depression, with scores ≥10 indicating the presence of clinically relevant symptoms. Multivariable logistic regression was used to calculate the odds ratio (OR) with 95% confidence interval (CI) of clinically relevant depressive symptoms in relation to the NLR. We performed the smooth curve fitting and established a weighted generalized additive model to identify the nonlinearity of NLR and depression in diabetes patients. To account for the nonlinear relationship between NLR and depression in diabetes patients, weighted two-piecewise linear model was applied.

Results

We included 2,820 eligible participants, of which 371 (12.4%) had clinically relevant depressive symptoms. In the unadjusted model, the OR (95% CI) of clinically relevant depressive symptoms for the second (NLR 1.75-2.57) and third (NLR >2.57) were 1.24 (0.90, 1.70) and 1.68 (1.23, 2.30), respectively, compared to the reference group (NLR < 1.75). After controlling for potential confounding factors, NLR was significantly associated with clinically relevant symptoms (odds ratio = 1.57, 95% confidence interval: 1.13–1.87; P for trend = .0078). Nonlinear relationships were observed, and a two-piecewise linear regression model was established. The inflection point of NLR was 2.87. To the left of the inflection point (NLR ≤ 2.87), the OR (95% CIs) was 1.33 (1.07–1.66) (P < .031).

Conclusions

Elevated levels of NLR are independently associated with increased odds of clinically relevant depressive symptoms in people with diabetes. Prospective study is needed to further analyze the role of NLR in depression in diabetic patients.

NLR Is Associated With Geriatric Depression in Chinese Women: A Community-Based Cross-Sectional Study in Eastern China

In recent years, the prevalence of depression has been increasing, causing a serious global burden of disease. Previous studies have proved that low-grade inflammation is involved in the process of depression. To explore the role of inflammation in the pathogenesis of senile depression, neutrophil to lymphocyte ratio (NLR) was used in this study, as a biological marker for non-specific inflammation. The present study was conducted among elderly adults from a randomly selected Community in Yangpu District, Shanghai from November 1 to December 30, 2017. 665 participants were included in the present study, including 276 males (median age was 68 years old) and 389 females (median age was 67 years old). NLR was calculated based on results of hematology examination. Depressive symptoms were assessed using the simplified version of Geriatric Depression Scale (GDS), the participant with total score greater than five points was considered to be depressed. The association between NLR and depression was evaluated separately for men and women. The prevalence of depression was 35.1% for men and 34.4% for women. No associations were found between NLR and depression among males. Nevertheless, compared with normal women, NLR was significantly increased in women with depressive symptoms (P = 0.020). Logistic regression analysis showed that NLR was independently associated with geriatric depression in women. The odds ratios (ORs) of depression was 2.152 (1.095, 4.227; P = 0.026) for the fourth compared with the first quartile of NLR. In conclusion, this study showed increased NLR was significantly associated with geriatric depression in women, but not men.