Relationship between major depression and insulin resistance: does it vary by gender or race/ethnicity among young adults aged 20-39 years?

Association between insulin resistance and serum insulin-like growth factor 1 levels in patients with non-remitting major depressive disorder

BACKGROUND

Major depressive disorder (MDD) is linked to an increased risk of diabetes; however, the underlying pathomechanism remains unknown. Although insulin-like growth factor 1 (IGF-1) is involved in the pathogenesis of both insulin resistance (IR) and MDD, no studies have investigated the relationship between IGF-1 and IR in patients with MDD.

METHODS

We recruited 120 patients with MDD (84 non-remitting patients and 36 remitting patients) and 99 control participants. Blood samples were collected after overnight fasting to investigate associations between serum and clinical factors, such as serum IGF-1 levels and homeostasis model assessment-insulin resistance (HOMA-IR).

RESULTS

Serum IGF-1 levels were higher in patients with non-remitting MDD than in control participants and patients with remitting MDD (P = 0.001 and P = 0.007, respectively). There were no significant differences in HOMA-IR between the three groups. HOMA-IR was positively correlated with serum IGF-1 levels in patients with non-remitting MDD (R = 0.355; P= 0.001) but not in control participants or patients with remitting MDD. A stepwise multiple regression analysis with various clinical factors revealed a positive association of serum IGF-1 levels and body mass index with HOMA-IR in patients with non-remitting MDD.

LIMITATIONS

This is a cross-sectional study and therefore we cannot draw firm conclusions about causal associations.

CONCLUSIONS

Serum IGF-1 levels may play a role in IR in patients with MDD who fail to achieve remission. Further studies, including longitudinal studies, are needed to determine the relationship between high serum IGF-1 levels and subsequent IR and diabetes risk.

The association between insulin resistance and depressive symptoms - A national representative cross-sectional study

OBJECTIVE

Increasing evidence suggests a positive association between insulin resistance (IR) and depression. However, whether sex-or body mass index-specific differences exist remains controversial, and only few studies have analyzed specific symptom domains. Thus, the present study aimed to analyze the association between IR and depressive symptom domains and to clarify the effects of sex and body mass index.

METHODS

The study sample comprised 4007 participants, aged 19-79, from the Korea National Health and Nutrition Examination Study 2020. Participants completed health interviews and examinations, providing data on circulating insulin and glucose levels, the Patient Health Questionnaire-9 (PHQ-9), and related covariates. IR was calculated using the homeostasis model assessment of insulin resistance. Associations between IR and PHQ-9 were analyzed using negative binomial regression with adjustments for the complex survey design.

RESULTS

The association between log-transformed IR and PHQ-9 total scores was statistically significant (incidence rate ratio [IRR] = 1.17, 95% confidence interval [CI] = 1.07-1.29, p = 0.001). Only body mass index specific differences were statistically significant, as the association was only significant in those without obesity (IRR = 1.21, 95% CI = 1.06-1.38, p = 0.005). IR was associated with cognitive/affective (IRR = 1.23, 95% CI = 1.08-1.41, p = 0.002) and somatic (IRR = 1.14, 95% CI = 1.04-1.25, p = 0.005) depressive symptom domains. Sensitivity analyses revealed similar results.

CONCLUSIONS

IR was positively associated with cognitive/affective and somatic depressive symptoms in non-obese individuals.

Clinical correlates and metabolic indicators of elevated fasting glucose in overweight/obese Chinese Han patients with first-episode and drug-naive major depressive disorder

BACKGROUND

Overweight/obese major depressive disorder (MDD) patients have a high probability of developing glucose metabolism disorders; however, the results are inconsistent due to the confounding variables involved in the studies. The purpose of this study was to explore the prevalence and risk factors for elevated fasting glucose in Chinese Han patients with overweight/obese first-episode and drug naïve (FEDN) MDD.

METHODS

The study used a cross-sectional design and recruited 1718 FEDN MDD patients between the ages of 18 and 60 years. Socio-demographic information, anthropometric data, and biochemical parameters were collected. The 17-item Hamilton Assessment Scale for Depression (HAMD), the 14-item Hamilton Anxiety Scale (HAMA), and the Positive and Negative Syndrome Scale (PANSS) positive subscale were used to assess symptoms of all patients.

RESULTS

MDD patients with elevated fasting glucose had higher TSH, TPOAb, TC, TG, LDL-C, systolic and diastolic blood pressure levels than those with normal fasting glucose. Logistic regression analysis showed that age, TSH, TgAb, TPOA, and TG were related factors for elevated fasting glucose, while TSH and combination all these five parameters had the potential to differentiate between patients with elevated fasting glucose and those with normal fasting glucose. Multifactorial regression analysis showed that TSH, TG, and LDL-C were independently associated with elevated fasting glucose.

CONCLUSION

Our findings suggest a high prevalence of elevated fasting glucose in overweight/obese FEDN MDD patients. Several clinically relevant factors and metabolic parameters are associated with elevated fasting glucose in overweight/obese FEDN MDD patients.

LIMITATION

Due to the cross-sectional design, no causal relationship could be derived.

Depression status and insulin resistance in adults with obesity: A cross-sectional study

OBJECTIVE

Insulin resistance (IR) frequently co-occurs with depression, but inconsistent associations between IR and depression have been reported, and less is known about the association in obesity, a major risk factor for both IR and depression. Thus the association between depression status and IR in a nationally representative sample of the US adults with obesity was evaluated.

METHODS

This cross-sectional study involved 3507 adults with obesity from National Health and Nutrition Examination Survey from 2005 to 2016. The homeostasis model assessment of insulin resistance (HOMA-IR) was used, where IR was defined as a HOMA-IR value greater than its 75^th percentile. The Patient Health Questionnaire 9 was used to assess the depression status. Multivariate logistic regression model was applied to evaluate the association between depression status and IR.

RESULTS

The cut-off value of HOMA-IR in adults with obesity was 5.5, and the prevalence of IR was 26.3% in men, 19.8% in women. The association of depression status with IR depended upon gender (P for depression status by gender interaction = 0.04). Depression status was positively associated with IR in women (P = 0.01), where the ORs (95% CIs) for the risk of IR in the mild, moderate, severe depression status were 1.79 (1.21-2.64), 1.95 (1.10-3.45), and 2.21 (1.04-4.71), respectively (P for trend = 0.002). No association was found in men (P = 0.91).

CONCLUSION

Positive association between IR and depression status was identified in women with obesity, where the risk of IR increased with the level of depression status, while no association was found in men with obesity.

Increased nitro-oxidative stress toxicity as a major determinant of increased blood pressure in mood disorders

BACKGROUND

Hypertension, atherogenicity and insulin resistance are major risk factors of cardiovascular disorder (CVD), which shows a strong comorbidity with major depression (MDD) and bipolar disorder (BD). Activated oxidative and nitrosative stress (O&NS), inflammatory pathways, and increased atherogenicity are shared pathways underpinning CVD and mood disorders.

METHODS

The current study examined the effects of lipid hydroperoxides (LOOH), superoxide dismutase (SOD), nitric oxide metabolites (NOx), advanced oxidation protein products (AOPP), and malondialdehyde (MDA) on systolic (SBP) and diastolic (DBP) blood pressure in 96 mood disordered patients and 60 healthy controls.

RESULTS

A large part of the variance in SBP (31.6%) was explained by the regression on a z unit-weighted composite score (based on LOOH, AOPP, SOD, NOx) reflecting nitro-oxidative stress toxicity (NOSTOX), coupled with highly sensitive C-reactive protein, body weight and use of antihypertensives. Increased DBP was best predicted (23.8%) by body mass index and NOSTOX. The most important O&NS biomarkers predicting an increased SBP were in descending order of significance: LOOH, AOPP and SOD. Higher levels of the atherogenic index of plasma, HOMA2 insulin resistance index and basal thyroid-stimulating hormone also contributed to increased SBP independently from NOSTOX. Although there were no significant changes in SBP/DBP in mood disorders, the associations between NOSTOX and blood pressure were significant in patients with mood disorders but not in healthy controls.

CONCLUSIONS

Activated O&NS pathways including increased lipid peroxidation and protein oxidation, which indicates hypochlorous stress, are the most important predictors of an increased BP, especially in patients with mood disorders.

Indices of insulin resistance and glucotoxicity are not associated with bipolar disorder or major depressive disorder, but are differently associated with inflammatory, oxidative and nitrosative biomarkers

BACKGROUND

Insulin resistance (IR) is a key factor in diabetes mellitus, metabolic syndrome (MetS) and obesity and may occur in mood disorders and tobacco use disorder (TUD), where disturbances of immune-inflammatory, oxidative and nitrosative stress (IO&NS) pathways are important shared pathophysiological pathways.

METHODS

This study aimed to a) examine IR and β-cell function as measured by the homeostasis model assessment of insulin resistance (HOMA-IR) and insulin sensitivity and β cell function (HOMA-B) and glucotoxicity (conceptualized as increased glucose levels versus lowered HOMA-B values) in 74 participants with major depressive disorder (MDD) and bipolar disorder, with and or without MetS and TUD, versus 46 healthy controls, and b) whether IR is associated with IO&NS biomarkers, including nitric oxide metabolites (NOx), lipid hydroperoxides (LOOH), plasma advanced oxidation protein products (AOPP), C-reactive protein (CRP), haptoglobin (Hp) and uric acid.

RESULTS

Mood disorders are not associated with changes in IR or glucotoxicity, although the number of mood episodes may increase IR. 47.8% of the variance in HOMA-IR is explained by AOPP and body mass index (BMI, both positively) and NOx, Hp and TUD (all inversely). 43.2% of the variance in HOMA-B is explained by NOx, Hp and age (all inversely associated) and higher BMI and sex. The glucotoxic index is strongly associated with NOx, Hp and BMI (positively), male gender and lower education.

LIMITATIONS

This is a cross-sectional study and therefore we cannot draw firm conclusions on causal associations.

CONCLUSIONS

Activated IO&NS pathways (especially increased Hp and NOx) increase glucotoxicity and exert very complex effects modulating IR. Mood disorders are not associated with increased IR.

Mood, food, and obesity

Food is a potent natural reward and food intake is a complex process. Reward and gratification associated with food consumption leads to dopamine (DA) production, which in turn activates reward and pleasure centers in the brain. An individual will repeatedly eat a particular food to experience this positive feeling of gratification. This type of repetitive behavior of food intake leads to the activation of brain reward pathways that eventually overrides other signals of satiety and hunger. Thus, a gratification habit through a favorable food leads to overeating and morbid obesity. Overeating and obesity stems from many biological factors engaging both central and peripheral systems in a bi-directional manner involving mood and emotions. Emotional eating and altered mood can also lead to altered food choice and intake leading to overeating and obesity. Research findings from human and animal studies support a two-way link between three concepts, mood, food, and obesity. The focus of this article is to provide an overview of complex nature of food intake where various biological factors link mood, food intake, and brain signaling that engages both peripheral and central nervous system signaling pathways in a bi-directional manner in obesity.

Depression and type 2 diabetes: a causal association?

There is a controversy regarding whether depression and type 2 diabetes are causally linked. To assess this issue, we review key findings for the association between depression and diabetes, and its underlying mechanisms. Findings from meta-analyses of cohort studies show a modestly sized bidirectional association between depression and type 2 diabetes (ie, depression predicts diabetes onset and diabetes predicts future depression). However, depression-related biological alterations in the hypothalamic-pituitary-adrenal cortex axis and the sympathetic nervous system, and subclinical inflammation, are not consistently linked with increased diabetes risk. The evidence for an association between depression and glycaemic traits (eg, glucose, insulin, insulin sensitivity, and insulin secretion) is also mixed. Diabetes increases the risk of depression to the same extent as do other chronic disorders (eg, cardiac diseases, osteoarthritis, lung disease, and poor hearing). At present, the available evidence suggests that pathophysiological changes preceding the onset of type 2 diabetes might not cause depression, nor might depression directly increase the risk of developing type 2 diabetes. Despite insufficient robust causal evidence, treating physicians should be aware of the co-occurrence of depression and type 2 diabetes.

Can low brain-derived neurotrophic factor levels be a marker of the presence of depression in obese women?

OBJECTIVE

Depression is a common condition in obese women that can result in severe impairment of their physical and social functioning. A deficiency of brain-derived neurotrophic factor (BDNF) is involved in the mechanism of depression. The aim of this study is to investigate whether BDNF levels differ between obese female patients and healthy controls and whether BDNF levels alter with affective states in depressive obese women.

METHODS

The study group included 40 obese, 40 preobese, and 40 normal weight women. BDNF levels were measured with an enzyme-linked immunosorbent assay in patient and control groups. For identifying the depression and anxiety status, Beck Depression/Anxiety Inventories were used; and for the evaluation of cognitive functions, the mini-mental state examination was used.

RESULTS

BDNF levels were significantly lower in obese patients compared to the control group (P<0.01). BDNF levels were significantly lower in obese patients with depression compared to the obese patients without depression (P<0.05). The Beck Depression Inventory showed a negative correlation with BDNF (r=-0.044; P<0.01) and a positive correlation with the Beck Anxiety Inventory (r=0.643; P<0.001), vitamin B12 levels (r=0.023; P<0.001), and insulin levels (r=0.257; P<0.05) in obese patients. When receiver operating characteristic curve analysis was used to analyze the suitability of BDNF to identify depression in obese women, the area under the curve for BDNF, 0.756, was found to be significant (P=0.025). BDNF levels lower than 70.2 pg/mL were associated with a higher prevalence of depressive symptoms.

CONCLUSION

The results of our study suggest that the decrease in BDNF levels can be used as a marker for depression diagnosis in obese patients.

Metabolic disturbances connecting obesity and depression

Obesity markedly increases the odds of developing depression. Depressed mood not only impairs motivation, quality of life and overall functioning but also increases the risks of obesity complications. Abdominal obesity is a better predictor of depression and anxiety risk than overall adipose mass. A growing amount of research suggests that metabolic abnormalities stemming from central obesity that lead to metabolic disease may also be responsible for the increased incidence of depression in obesity. As reviewed here, a higher mass of dysfunctional adipose tissue is associated with several metabolic disturbances that are either directly or indirectly implicated in the control of emotions and mood. To better comprehend the development of depression in obesity, this review pulls together select findings addressing the link between adiposity, diet and negative emotional states and discusses the evidence that alterations in glucocorticoids, adipose-derived hormones, insulin and inflammatory signaling that are characteristic of central obesity may be involved.