Vitamin D: an anti-inflammatory treatment option for depression?

Vitamin D: Between the brightness of the sun and the darkness of depression

INTRODUCTION

The scientific literature suggests a relationship between vitamin D (VitD) and the onset, treatment and prognosis of depression. However, this line of research continues to be controversial. The aim of the study was to analyse the relationship between depression and VitD values, controlling for the influence of the season.

MATERIAL AND METHODS

Observational and cross-sectional study. The sample was made up of 150 adult female volunteer participants (aged between 28 and 78 years). The sample was stratified into three groups: a) depression without treatment, b) depression under treatment with antidepressants, and c) without depression (control). VitD values (ng/ml) were compared.

RESULTS

Significant differences were found between the three groups surveyed. The group of participants with depression without treatment obtained the lowest VitD values (mean 18.62ng/ml; SD 8.42), compatible with severe insufficiency. The group of participants with depression in treatment obtained higher values than the previous group, although in an insufficient range (mean 23.80ng/ml; SD 11.30). The third group (control) obtained the highest values and in accordance with the desirable range (mean 30.19ng/ml; SD 10.21). There were no age differences between the groups. When controlling for possible effects of the season, the previous differences in VitD between the three groups were maintained, with an evident decrease of all the mean levels in the winter period.

CONCLUSIONS

Depression is associated with insufficient VitD values. Treatment with antidepressants improves these values, although they continue to be insufficient. The findings of this study reinforce the evidence for an association between depression and VitD.

PCOS and Depression: Common Links and Potential Targets

PCOS or polycystic ovary syndrome is a common endocrine disorder that occurs during the reproductive age in females. It manifests in the form of a wide range of symptoms including (but not limited to) hirsutism, amenorrhea, oligomenorrhea, obesity, acne vulgaris, infertility, alopecia, and insulin resistance. The incidence of depression in PCOS population is increasing as compared to the general population. Increased depression in PCOS significantly alters the quality of life (QOL) of affected females. Also, self-esteem is found to be low in both depression and PCOS. The loss in self-esteem in such patients can be largely attributed to the associated factors including (but not limited to) obesity, acne, androgenic alopecia, and hirsutism. The reason behind the occurrence of depression in PCOS remains elusive to date. Literature suggests that there is an overlap of clinical symptoms between depression and PCOS. As the symptoms overlap, there is a possibility of common associations between depression, PCOS, and PCOS-associated abnormalities including insulin resistance (IR), obesity, CVD, and androgen excess. Studies demonstrate that depression is an inflammatory disorder marked with increased levels of inflammatory markers. On the other hand, PCOS is also regarded as a pro-inflammatory state that is characterized by increased levels of pro-inflammatory markers. Thus, there is a possibility of an inflammatory relationship existing between depression and PCOS. It is also possible that the inflammatory markers in PCOS can cross the blood-brain barrier (BBB) leading to the development of depression. Through the present review, we have attempted to shed light on common associations/shared links between depression and PCOS with respect to the levels of cortisol, androgen, vitamin D, neurotransmitters, monoaminoxidase (MAO), and insulin-like growth factor-1 (IGF-1). Tracking down common associations between depression and PCOS will help find potential drug therapies and improve the QOL of females with depression in PCOS.

Vitamin D: Between the Brightness of the sun and the Darkness of Depression

INTRODUCTION

The scientific literature suggests a relationship between vitamin D (VitD) and the onset, treatment and prognosis of depression. However, this line of research continues to be controversial. The aim of the study was to analyse the relationship between depression and VitD values, controlling for the influence of the season.

MATERIAL AND METHODS

Observational and cross-sectional study. The sample was made up of 150 adult female volunteer participants (aged between 28 and 78 years). The sample was stratified into three groups: a) depression without treatment, b) depression under treatment with antidepressants, and c) without depression (control). VitD values (ng/ml) were compared.

RESULTS

Significant differences were found between the three groups surveyed. The group of participants with depression without treatment obtained the lowest VitD values (mean 18.62 ng/ml; SD 8.42), compatible with severe insufficiency. The group of participants with depression in treatment obtained higher values than the previous group, although in an insufficient range (mean 23.80 ng/ml; SD 11.30). The third group (control) obtained the highest values and in accordance with the desirable range (mean 30.19 ng/ml; SD 10.21). There were no age differences between the groups. When controlling for possible effects of the season, the previous differences in VitD between the three groups were maintained, with an evident decrease of all the mean levels in the winter period.

CONCLUSIONS

Depression is associated with insufficient VitD values. Treatment with antidepressants improves these values, although they continue to be insufficient. The findings of this study reinforce the evidence for an association between depression and VitD.

Efficacy of vitamin D supplementation in major depression: A meta-analysis of randomized controlled trials

Background:

There is a need to develop and periodically evaluate new treatment strategies in major depression due to the high burden of nonresponse and inadequate response to antidepressants.

Aim:

We aimed to assess the effect of vitamin D supplementation on depression symptom scores among individuals with clinically diagnosed major depression.

Materials and Methods:

Electronic search of databases was carried out for published randomized controlled trials in English language, peer-reviewed journals from inception till August 2017. Outcome measure used for effect size calculation was depression symptom scores. Effect sizes for the trials were computed using standardized mean difference (Cohen's d), and I² test was used to assess sample heterogeneity. Pooled mean effect sizes were derived using both fixed and random-effects model. Critical appraisal of studies was done using the Cochrane risk of bias assessment tool.

Results:

A total of four trials involving 948 participants were included in the study. In three trials, the intervention group received oral vitamin D supplementation whereas in one parenteral vitamin D was given. Pooled mean effect size for vitamin D supplementation on depressive symptom ratings in major depression was 0.58 (95% confidence interval, 0.45–0.72). The I² value for heterogeneity was 0 suggesting low heterogeneity among studies. Egger plot intercept indicated minimal publication bias.

Conclusion:

Vitamin D supplementation favorably impacted depression ratings in major depression with a moderate effect size. These findings must be considered tentative owing to the limited number of trials available and inherent methodological bias noted in few of them.

Vitamin D and inflammation in major depressive disorder

BACKGROUND

Increased inflammation is reported in Major Depressive Disorder (MDD), which may be more pronounced in suicidal subjects. Vitamin D deficiency may drive this pro-inflammatory state due to vitamin D's anti-inflammatory effects.

METHODS

We quantified plasma 25-hydroxyvitamin D (25(OH)D) and inflammatory markers interleukin (IL)-6 and tumor necrosis factor (TNF)-α, and other inflammatory indices, neutrophil-to-lymphocyte ratio (NLR) and white blood cell count (WBC) in 48 un-medicated MDD subjects (n = 17 with mild-to-moderate suicidal ideation [SI]) and 54 controls. IL-6 and TNF-α were combined into a composite inflammation score.

RESULTS

There were no significant differences in 25(OH)D levels between MDD and controls (p = 0.24) or between MDD with and without SI (p = 0.61). However, 25(OH)D was negatively correlated with all measured inflammatory markers; these correlations were stronger in MDD subjects, and particularly in those with SI. MDD status significantly moderated the relationships between 25(OH)D and NLR (p = 0.03), and 25(OH)D and WBC (p < 0.05), and SI significantly moderated the relationship between 25(OH)D and NLR (p = 0.03).

LIMITATIONS

The study was cross-sectional, thereby limiting causal inference, and had a small sample size. Only seventeen of the MDD subjects had SI.

CONCLUSION

While 25(OH)D levels did not significantly differ in MDD vs. controls, or in MDD with or without SI, lower 25(OH)D was associated with indices of immune activation in MDD, especially in cases with SI. Although our findings do not address causality, they are consistent with findings that relatively low 25(OH)D levels in MDD are associated with a pro-inflammatory state.

Changes in the serum levels of inflammatory cytokines in antidepressant drug-naïve patients with major depression

Major depressive disorder (MDD) is a common condition that afflicts the general population across a broad spectrum of ages and social backgrounds. The inflammatory hypothesis of depression posits that immune hyperactivation and dysregulated cytokine production are involved in depression. To investigate cytokine profiles in patients with MDD, we examined the levels of the pro-inflammatory cytokines interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor (TNF)-α, and those of the anti-inflammatory cytokines IL-10 and transforming growth factor (TGF)-β1 in antidepressant drug-naïve patients with MDD. Compared to healthy controls, patients with MDD had significantly higher levels of IL-1β, IL-10, and TNF-α, but significantly lower levels of IL-8. There were no significant differences in the levels of IL-6 or TGF-β1. We found linear correlations between IL-1β, TNF-α, and IL-8, and the severity of depression, as well as between IL-8 and anxiety level in patients with comorbid anxiety disorder. In addition, higher IL-1β and TNF-α levels were associated with higher Hamilton Depression Rating Scale (HAMD) scores, while higher IL-8 levels were associated with lower HAMD and Hamilton Anxiety Rating Scale scores. Here we present evidence of changes in cytokine levels in antidepressant drug-naïve patients with MDD. Abnormal expression of inflammatory cytokines in patients with depression suggests that depression activates an inflammatory process. Immunological abnormalities may be involved in the pathophysiology of depression.

Vitamin D is independently associated with depression in overweight women with and without PCOS

BACKGROUND

Depression, anxiety, and inflammation are common in polycystic ovary syndrome (PCOS). Inflammation may adversely impact on mood and vitamin D has been associated with both mood disorders and inflammation in the general population, but these relationships have not been studied in PCOS. The aim of this study was to investigate the association among 25 hydroxy-Vitamin D (25OHVD) status, anxiety, depression, and inflammation in women with and without PCOS.

METHODS

Cross-sectional study in overweight or obese premenopausal women with (n = 50) and without (n = 23) PCOS. Primary outcome measures were 25OHVD, mood (Hospital Anxiety and Depression questionnaire), and inflammation (highly sensitive C-reactive protein (hsCRP)).

RESULTS

Vitamin D deficiency (25OHVD<50 nmol/L) (46% versus 39%, p = 0.311) and 25OHVD (50.4 ± 22.2 nmol/L versus 51.6 ± 19.0 nmol/L, p = 0.828) were not significantly different in women with and without PCOS. For all women combined, 25OHVD was the only significant independent predictor of depression (β = -0.063 ± 0.021, p = 0.005) and hsCRP (β = -0.041 ± 0.015, p = 0.010).

CONCLUSIONS

Vitamin D deficiency is common in both women with and without PCOS with no differences between the groups. Vitamin D is independently associated with depression and inflammation in overweight women both with and without PCOS. Further investigation to clarify the interrelationship among vitamin D, inflammation and depression is required to identify optimal prevention and treatment strategies for psychological and metabolic dysfunction in PCOS.