Insulin resistance and depressive symptoms in young adult males: findings from Finnish military conscripts

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.

Increased cardiovascular events in young patients with mental disorders: a nationwide cohort study

AIMS

It remains unclear whether young patients with mental disorders have a higher risk of cardiovascular diseases than does the general population. Using a nationwide database, we investigated the prognostic association between the risks of myocardial infarction (MI), ischaemic stroke (IS), and mental disorders in young patients.

METHODS AND RESULTS

Young patients aged between 20 and 39 years old who underwent nationwide health examinations between 2009 and 2012 were screened. A total of 6 557 727 individuals were identified and subsequently classified according to mental disorders including depressive disorder, bipolar disorder, schizophrenia, insomnia, anxiety disorder, post-traumatic stress disorder, personality disorder, somatoform disorder, eating disorder, and substance use disorder. Patients were then followed up for MI and IS until December 2018. Patients with mental disorders did not show unfavourable lifestyle behaviours or worse metabolic profiles than their counterparts. During the follow-up period (median, 7.6 years; interquartile range, 6.5-8.3), 16 133 cases of MI and 10 509 cases of IS occurred. Patients with mental disorders had higher risks of MI (log-rank P = 0.033 in eating disorder and log-rank P < 0.001 in all other mental disorders). Patients with mental disorders had higher risks of IS except post-traumatic stress disorder (log-rank P = 0.119) and eating disorder (log-rank P = 0.828). After adjusting for covariates, the overall diagnosis and each mental disorder were independently associated with increased cardiovascular endpoints.

CONCLUSION

Mental disorders in young patients may have deleterious effects which increase the incidence of MI and IS. Prevention efforts are needed to prevent MI and IS in young patients with mental disorders.

Major Depressive Disorder and Bipolar Disorder Predispose Youth to Accelerated Atherosclerosis and Early Cardiovascular Disease: A Scientific Statement From the American Heart Association

In the 2011 "Expert Panel on Integrated Guidelines for Cardiovascular Health and Risk Reduction in Children and Adolescents," several medical conditions among youth were identified that predispose to accelerated atherosclerosis and early cardiovascular disease (CVD), and risk stratification and management strategies for youth with these conditions were elaborated. Major depressive disorder (MDD) and bipolar disorder (BD) among youth satisfy the criteria set for, and therefore merit inclusion among, Expert Panel tier II moderate-risk conditions. The combined prevalence of MDD and BD among adolescents in the United States is ≈10%, at least 10 times greater than the prevalence of the existing moderate-risk conditions combined. The high prevalence of MDD and BD underscores the importance of positioning these diseases alongside other pediatric diseases previously identified as moderate risk for CVD. The overall objective of this statement is to increase awareness and recognition of MDD and BD among youth as moderate-risk conditions for early CVD. To achieve this objective, the primary specific aims of this statement are to (1) summarize evidence that MDD and BD are tier II moderate-risk conditions associated with accelerated atherosclerosis and early CVD and (2) position MDD and BD as tier II moderate-risk conditions that require the application of risk stratification and management strategies in accordance with Expert Panel recommendations. In this scientific statement, there is an integration of the various factors that putatively underlie the association of MDD and BD with CVD, including pathophysiological mechanisms, traditional CVD risk factors, behavioral and environmental factors, and psychiatric medications.

Acne vulgaris, probiotics and the gut-brain-skin axis: from anecdote to translational medicine

Acne vulgaris has long been postulated to feature a gastrointestinal mechanism, dating back 80 years to dermatologists John H. Stokes and Donald M. Pillsbury. They hypothesised that emotional states (e.g. depression and anxiety) could alter normal intestinal microbiota, increase intestinal permeability, and contribute to systemic inflammation. They were also among the first to propose the use of probiotic Lactobacillus acidophilus cultures. In recent years, aspects of this gut-brain-skin theory have been further validated via modern scientific investigations. It is evident that gut microbes and oral probiotics could be linked to the skin, and particularly acne severity, by their ability to influence systemic inflammation, oxidative stress, glycaemic control, tissue lipid content, and even mood. This intricate relationship between gut microbiota and the skin may also be influenced by diet, a current area of intense scrutiny by those who study acne. Here we provide a historical background to the gut-brain-skin theory in acne, followed by a summary of contemporary investigations and clinical implications.

PPAR-γ agonism as a modulator of mood: proof-of-concept for pioglitazone in bipolar depression

BACKGROUND

Insulin resistance and other cardio-metabolic risk factors predict increased risk of depression and decreased response to antidepressant and mood stabilizer treatments. This proof-of-concept study tested whether administration of an insulin-sensitizing peroxisome proliferator-activated receptor (PPAR)-γ agonist could reduce bipolar depression symptom severity. A secondary objective was to determine whether levels of highly sensitive C-reactive protein and interleukin (IL)-6 predicted treatment outcome.

METHODS

Patients (n = 34) with bipolar disorder (I, II, or not otherwise specified) and metabolic syndrome/insulin resistance who were currently depressed (Quick Inventory of Depressive Symptoms [QIDS] total score ≥11) despite an adequate trial of a mood stabilizer received open-label, adjunctive treatment with the PPAR-γ agonist pioglitazone (15-30 mg/day) for 8 weeks. The majority of participants (76 %, n = 26) were experiencing treatment-resistant bipolar depression, having already failed two mood stabilizers or the combination of a mood stabilizer and a conventional antidepressant.

RESULTS

Supporting an association between insulin sensitization and depression severity, pioglitazone treatment was associated with a decrease in the total Inventory of Depressive Symptomatology (IDS-C30) score from 38.7 ± 8.2 at baseline to 21.2 ± 9.2 at week 8 (p < 0.001). Self-reported depressive symptom severity and clinician-rated anxiety symptom severity significantly improved over 8 weeks as measured by the QIDS (p < 0.001) and Structured Interview Guide for the Hamilton Anxiety Scale (p < 0.001), respectively. Functional improvement also occurred as measured by the change in total score on the Sheehan Disability Scale (-17.9 ± 3.6; p < 0.001). Insulin sensitivity increased from baseline to week 8 as measured by the Insulin Sensitivity Index derived from an oral glucose tolerance test (0.98 ± 0.3; p < 0.001). Higher baseline levels of IL-6 were associated with greater decrease in depression severity (parameter estimate β = -3.89, standard error [SE] = 1.47, p = 0.015). A positive correlation was observed between improvement in IDS-C30 score and change in IL-6 (r = 0.44, p < 0.01).

CONCLUSIONS

Open-label administration of the PPAR-γ agonist pioglitazone was associated with improvement in depressive symptoms and reduced cardio-metabolic risk. Reduction in inflammation may represent a novel mechanism by which pioglitazone modulates mood. (ClinicalTrials.gov Identifier: NCT00835120).

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

BACKGROUND

To examine the relationship between major depression and insulin resistance by gender and race/ethnicity among young adults without diabetes mellitus.

METHODS

Secondary analyses of cross-sectional data from the National Health and Nutrition Examination Survey 1999-2008 were performed (n = 2265). Major depression was measured by the Composite International Diagnostic Interview and the Patient Health Questionnaire 9. Insulin resistance was measured by the homeostasis model assessment of insulin resistance. Multivariate logistic regression analyses adjusted for risk factors of insulin resistance were conducted.

RESULTS

There was a significant negative association between major depression and insulin resistance among men. For women, no significant association was found. There was no significant interaction between race/ethnicity and major depression on insulin resistance (Wald χ(2) = 4.2927, P = 0.2315). Body mass index (BMI) and waist circumference (WC) were significantly associated with insulin resistance among both men (odds ratio [OR] 1.255, 95% confidence interval [CI] 1.195-1.318 for BMI; OR 1.095, 95% CI 1.076-1.115 for WC) and women (OR 1.220, 95% CI 1.182-1.260 for BMI; OR 1.084, 95% CI 1.064-1.105 for WC).

CONCLUSIONS

There are gender differences in the relationship between major depression and insulin resistance among adults aged 20-39 years. No evidence was found to support the role of race/ethnicity in this relationship. Health care professionals should be aware of risk factors for insulin resistance and develop interventions to help prevent the progression of insulin resistance to type 2 diabetes mellitus.

The association of depression and perceived stress with beta cell function between African and Haitian Americans with and without type 2 diabetes

Background:

Diabetes and diabetes-related complications are major causes of morbidity and mortality in the United States. Depressive symptoms and perceived stress have been identified as possible risk factors for beta cell dysfunction and diabetes. The purpose of this study was to assess associations between depression symptoms and perceived stress with beta cell function between African and Haitian Americans with and without type 2 diabetes.

Participants and Methods:

Informed consent and data were available for 462 participants (231 African Americans and 231 Haitian Americans) for this cross-sectional study. A demographic questionnaire developed by the Primary Investigator was used to collect information regarding age, gender, smoking, and ethnicity. Diabetes status was determined by self-report and confirmed by fasting blood glucose. Anthropometrics (weight, and height and waist circumference) and vital signs (blood pressure) were taken. Blood samples were drawn after 8 – 10 hours over-night fasting to measure lipid panel, fasting plasma glucose and serum insulin concentrations. The homeostatic model assessment, version 2 (HOMA2) computer model was used to calculate beta cell function. Depression was assessed using the Beck Depression Inventory-II (BDI-II) and stress levels were assessed using the Perceived Stress Scale (PSS).

Results:

Moderate to severe depressive symptoms were more likely for persons with diabetes (p = 0.030). There were no differences in perceived stress between ethnicity and diabetes status (p = 0.283). General linear models for participants with and without type 2 diabetes using beta cell function as the dependent variable showed no association with depressive symptoms and perceived stress; however, Haitian Americans had significantly lower beta cell function than African Americans both with and without diabetes and adjusting for age, gender, waist circumference and smoking. Further research is needed to compare these risk factors in other race/ethnic groups.

Does pioglitazone improve depression through insulin-sensitization? Results of a randomized double-blind metformin-controlled trial in patients with polycystic ovarian syndrome and comorbid depression

Thiazolidinediones have shown beneficial effects in short-term treatment of depression. However, it is unclear whether the antidepressant efficacy of these agents is related to their insulin-sensitizing action. We conducted the present study to compare the antidepressant efficacy of pioglitazone with another insulin-sensitizer, metformin, in obese patients with concomitant polycystic ovarian syndrome (PCOS) and major depressive disorder (MDD). In a six-week double-blind study, 50 patients with PCOS and MDD (DSM-IV-TR criteria) with Hamilton depression rating scale (HDRS) score of <20, randomly received pioglitazone (15 mg twice daily; PO) or metformin (750 mg twice daily; PO). Assessment was done using HDRS (weeks 0, 3, 6) together with fasting Insulin, glucose, and lipid profile, liver enzymes, homeostatic model assessment of insulin resistance (HOMA-IR), anthropometric measures, and serum androgens (weeks 0 and 6). Pioglitazone was superior to metformin in reducing HDRS scores at the end of the study [38.3% versus 8.3% reduction from baseline scores, F(1, 37) = 73.513, P<0.001]. Changes from baseline in HOMA-IR values at week 6 were not significantly different between the two groups (P = 0.888). Baseline (but not follow-up) HDRS and HOMA-IR values were significantly correlated (r = 0.393, P = 0.012). In multiple regression analysis, treatment with pioglitazone independent of HOMA-IR values predicted greater score reduction on HDRS at week 6 (standardized beta = 0.801, P<0.001). Biochemical and hormonal profile did not differ between the two groups at week 6. Metformin was associated with higher frequency of gastrointestinal side effects (P = 0.014). In summary, we showed that pioglitazone improved depression with mechanisms largely unrelated to its insulin-sensitizing action (registration number: IRCT201106081556N23).

Glycemia, insulin resistance, insulin secretion, and risk of depressive symptoms in middle age

OBJECTIVE

The extent to which abnormal glucose metabolism increases the risk of depression remains unclear. In this study, we investigated prospective associations of levels of fasting glucose and fasting insulin and indices of insulin resistance and secretion with subsequent new-onset depressive symptoms (DepS).

RESEARCH DESIGN AND METHODS

In this prospective cohort study of 3,145 adults from the Whitehall II Study (23.5% women, aged 60.6 ± 5.9 years), baseline examination included fasting glucose and insulin level, the homeostasis model assessment of insulin resistance (HOMA2-%IR), and the homeostasis model assessment of β-cell insulin secretion (HOMA2-%B). DepS (Center for Epidemiologic Studies Depression Scale ≥16 or use of antidepressive drugs) were assessed at baseline and at 5-year follow-up.

RESULTS

Over the 5-year follow-up, DepS developed in 142 men and 84 women. Women in the lowest quintile of insulin secretion (HOMA2-%B ≤55.3%) had 2.18 (95% CI 1.25-3.78) times higher odds of developing DepS than those with higher insulin secretion. This association was not accounted for by inflammatory markers, cortisol secretion, or menopausal status and hormone replacement therapy. Fasting insulin measures were not associated with DepS in men, and fasting glucose measures were not associated with new-onset DepS in either sex.

CONCLUSIONS

Low insulin secretion appears to be a risk factor for DepS in middle-aged women, although further work is required to confirm this finding.

Psychosocial factors associated with depressive mood in Israeli obese adolescents

This study aimed to compare levels of depressive symptoms between normal-weight and obese Israeli adolescents and to identify sociodemographic factors that may explain differences in depression between these groups. Thirty normal-weight and 49 obese patients aged 12–18 years participated in this study. The obese group had a significantly higher depression score. On linear regression analysis, obesity, lower parental income, and lower self-esteem were significantly associated with a higher depression score. This model explained 32.4 percent of the variance. The results indicate that psychosocial assessment and identification of depressive signs should be considered integral components in the management of adolescent obesity.

Abnormal glucose tolerance, white blood cell count, and telomere length in newly diagnosed, antidepressant-naïve patients with depression

Chronic mood disorders have been associated with a shortened telomere, a marker of increased mortality rate and aging, and impaired cellular immunity. However, treatment may confound these relationships. We examined the relationship of glucose tolerance, white blood cell count and telomere length to depression in newly diagnosed, antidepressant-naïve patients. Subjects with major depression (n=15), and matched healthy control subjects (n=70) underwent a two-hour oral glucose tolerance test and evaluation of blood cell count and telomere content. The depression group had significantly higher two-hour glucose concentrations and a lower lymphocyte count than control subjects (respective means [SD] for two-hour glucose were 125.0mg/dL [67.9] vs 84.6 [25.6] (p<.001); for lymphocyte count 2.1×10(9)/L [0.6] vs 2.5×10(9)/L [0.7] p=.028). Telomere content was significantly shortened in the depression group (87.9 [7.6]) compared to control subjects (101.0 [14.3]; p<0.01). Abnormal glucose tolerance, lymphopenia and a shortened telomere are present early in the course of depression independently of the confounding effect of antidepressant treatment, supporting the concept of major depression as an accelerated aging disease.

A systematic review and meta-analysis of the association between depression and insulin resistance

OBJECTIVE

Depression is associated with the onset of type 2 diabetes. A systematic review and meta-analysis of observational studies, controlled trials, and unpublished data was conducted to examine the association between depression and insulin resistance (IR).

RESEARCH DESIGN AND METHODS

Medline, EMBASE, and PsycINFO were searched for studies published up to September 2011. Two independent reviewers assessed the eligibility of each report based on predefined inclusion criteria (study design and measure of depression and IR, excluding prevalent cases of diabetes). Individual effect sizes were standardized, and a meta-analysis was performed to calculate a pooled effect size using random effects. Subgroup analyses and meta-regression were conducted to explore any potential source of heterogeneity between studies.

RESULTS

Of 967 abstracts reviewed, 21 studies met the inclusion criteria of which 18 studies had appropriate data for the meta-analysis (n = 25,847). The pooled effect size (95% CI) was 0.19 (0.11-0.27) with marked heterogeneity (I(2) = 82.2%) using the random-effects model. Heterogeneity between studies was not explained by age or sex, but could be partly explained by the methods of depression and IR assessments.

CONCLUSIONS

A small but significant cross-sectional association was observed between depression and IR, despite heterogeneity between studies. The pathophysiology mechanisms and direction of this association need further study using a purposively designed prospective or intervention study in samples at high risk for diabetes.

A review of the association between depression and insulin resistance: pitfalls of secondary analyses or a promising new approach to prevention of type 2 diabetes?

We review the validity of the evidence for an association between depression and the risk of insulin resistance (IR). We describe the potentially plausible biological and behavioral mechanisms that explain how depression increases the risk of IR and consequent overt diabetes. We have identified gaps in the literature to guide future research. Evidence for bidirectional associations between depression and IR is inconsistent. Results showing positive associations between depression and IR are derived from cross-sectional studies, whereas negative findings are typically reported in cohort studies. On the other hand, tentative trial evidence suggests that the effective treatment of depression can improve IR, and that lifestyle programs improve IR and reduce depressive symptoms. These emerging themes could lead to potential new multidisciplinary approaches to preventing diabetes.

Polycystic ovary syndrome: etiology, pathogenesis and diagnosis

Polycystic ovary syndrome (PCOS) is the most common endocrinopathy in women of reproductive age, with a prevalence of up to 10%. Various diagnostic criteria have been proposed, generally centered around the features of hyperandrogenism and/or hyperandrogenemia, oligo-ovulation and polycystic ovarian morphology. Insulin resistance is present in a majority of cases, with compensatory hyperinsulinemia contributing to hyperandrogenism via stimulation of ovarian androgen secretion and inhibition of hepatic sex hormone-binding globulin production. Adipose tissue dysfunction has been implicated as a contributor to the insulin resistance observed in PCOS. Environmental and genetic factors also have a role in the development of PCOS. The syndrome is associated with numerous morbidities, including infertility, obstetrical complications, type 2 diabetes mellitus, cardiovascular disease, and mood and eating disorders. Despite these morbidities, PCOS may be common in our society owing to evolutionary advantages of the syndrome in ancient times, including smaller family sizes, reduced exposure to childbirth-related mortality, increased muscle mass and greater capacity to store energy. The diagnosis of PCOS hinges on establishing key features while ruling out other hyperandrogenic or oligo-ovulatory disorders. Treatment is focused on the goals of ameliorating hyperandrogenic symptoms, inducing ovulation and preventing cardiometabolic complications.

The relationship between psychosocial stress, age, BMI, CRP, lifestyle, and the metabolic syndrome in apparently healthy subjects

The aim of this cross-sectional study was to examine the factors which may be associated with the metabolic syndrome by exploring the relationship between psychosocial stress, age, body mass index (BMI), C-reactive protein (CRP), lifestyle factors, and the components of the metabolic syndrome, such as glycated hemoglobin (HbA1c), fasting blood sugar (FBS), body fat percentage, and triglyceride concentration, among apparently healthy subjects. Psychosocial stress was measured by the use of the inventory to measure psychosocial stress (IMPS). One thousand four hundred and ninety-nine people out of 1,941 public school workers admitted to a hospital for a medical check-up responded to the IMPS, yielding a response rate of 77.2%. A total of 1,201 workers excluding 298 who were taking medication for various diseases were analyzed with the use of hierarchical multiple regression models. It was found that IMPS-measured stress score, age, BMI, and smoking habit were associated with an increase in glycated hemoglobin among men, while alcohol consumption was associated with a decrease in glycated hemoglobin. Stress score, age, BMI, and alcohol consumption were found to be associated with an increase in FBS among men, while smoking and exercise habits were associated with a decrease in FBS. CRP was found to be associated with an increase in body fat percentage among men, though stress score was not associated with an increase in body fat percentage. Stress score, age, and BMI were associated with an increase in triglyceride concentration among women. The findings of the present study seem to be in line with the hypothesis that psychosocial stress plays an important role in developing the metabolic syndrome, which may be associated with inflammatory processes in the vascular wall, resulting in atherosclerosis and cardiovascular disease.

Acne vulgaris, probiotics and the gut-brain-skin axis - back to the future?

Over 70 years have passed since dermatologists John H. Stokes and Donald M. Pillsbury first proposed a gastrointestinal mechanism for the overlap between depression, anxiety and skin conditions such as acne. Stokes and Pillsbury hypothesized that emotional states might alter the normal intestinal microflora, increase intestinal permeability and contribute to systemic inflammation. Among the remedies advocated by Stokes and Pillsbury were Lactobacillus acidophilus cultures. Many aspects of this gut-brain-skin unifying theory have recently been validated. The ability of the gut microbiota and oral probiotics to influence systemic inflammation, oxidative stress, glycemic control, tissue lipid content and even mood itself, may have important implications in acne. The intestinal microflora may also provide a twist to the developing diet and acne research. Here we provide a historical perspective to the contemporary investigations and clinical implications of the gut-brain-skin connection in acne.

Clinical implications of lipid peroxidation in acne vulgaris: old wine in new bottles

Acne vulgaris is a common dermatological disorder, one that is frequently associated with depression, anxiety and other psychological sequelae. In recent years there has been an increasing focus on the extent to which oxidative stress is involved in the pathophysiology of acne. Emerging studies have shown that patients with acne are under increased cutaneous and systemic oxidative stress. Indeed, there are indications that lipid peroxidation itself is a match that lights an inflammatory cascade in acne. The notion that lipid peroxidation is a 'starter gun' in acne is not a new one; here we review the nearly 50-year-old lipid peroxidation theory and provide a historical perspective to the contemporary investigations and clinical implications.

In addition, we present a novel hypothesis in which lipid peroxidation may be priming an increased susceptibility to co-morbid depression and anxiety in those with acne. The emerging research on the systemic burden of oxidative stress in acne sheds further light on the brain-skin axis. The recent findings also suggest potential avenues of approach for the treatment of acne via specific nutrients, dietary modifications, oral and topical interventions.

Major depressive disorder and insulin resistance in nondiabetic young adults in the United States: the National Health and Nutrition Examination Survey, 1999-2002

OBJECTIVE

The association between depression and insulin resistance has been evaluated in previous studies with conflicting results. This study aimed to explore the relationship between major depressive disorder (MDD) and insulin resistance among nondiabetic young adult men and women in the United States.

METHOD

Analyses of cross-sectional data from the National Health and Nutrition Examination Survey (NHANES), 1999-2002, were conducted. The nationally representative sample consisted of 279 men and 358 women aged 20-39 years. MDD was determined by the WHO Composite International Diagnostic Interview (CIDI). Insulin resistance was measured by the homeostasis model assessment for insulin resistance.

RESULTS

Of 637 subjects, 16 men and 18 women had MDD (weighted percentage = 6.6%, SE = 1.2). Using logistic regression, no significant association was found between MDD and insulin resistance among the nondiabetic young adults in bivariate analysis (β = -0.01, OR = 0.99, 95% CI = [0.38, 2.57], p = .98). A significant interaction effect between gender and MDD was observed. For men, MDD was negatively associated with insulin resistance after adjusting for age, race/ethnicity, waist circumference, smoking status, systolic blood pressure and triglyceride level (β = -2.12, OR = 0.12, 95% CI = [0.02, 0.62], p = .01). No significant association between MDD and insulin resistance among women was found (β = 0.61, OR = 1.84, 95% CI = [0.47, 7.14], p = .38).

CONCLUSIONS

Overall findings suggest there is no significant association between MDD and insulin resistance among nondiabetic young adults aged 20-39 years. However, gender differences in this relationship were noted.

Depression and insulin resistance: cross-sectional associations in young adults

OBJECTIVE

To examine the association between depressive disorder and insulin resistance in a sample of young adults using the Composite International Diagnostic Interview to ascertain depression status.

RESEARCH DESIGN AND METHODS

Cross-sectional data were collected from 1,732 participants aged between 26 and 36 years. Insulin resistance was derived from blood chemistry measures of fasting insulin and glucose using the homeostasis model assessment method. Those identified with mild, moderate, or severe depression were classified as having depressive disorder.

RESULTS

The 12-month prevalence of depressive disorder was 5.4% among men and 11.7% among women. In unadjusted models mean insulin resistance was 17.2% (95% CI 0.7-36.0%, P = 0.04) higher in men and 11.4% (1.5-22.0%, P = 0.02) higher in women with depressive disorder. After adjustment for behavioral and dietary factors, the increased level of insulin resistance associated with depressive disorder was 13.2% (-3.1 to 32.3%, P = 0.12) in men and 6.1% (-4.1 to 17.4%, P = 0.25) in women. Waist circumference was identified as a mediator in the relationship between depression and insulin resistance, reducing the beta coefficient in the fully adjusted models in men by 38% and in women by 42%.

CONCLUSIONS

A positive association was found between depressive disorder and insulin resistance in this population-based sample of young adult men and women. The association seemed to be mediated partially by waist circumference.

Glucocorticoids. Mood, memory, and mechanisms

Elevated circulating levels of glucocorticoids are associated with psychiatric symptoms across several different conditions. It remains unknown if this hormonal abnormality is a cause or an effect of the psychiatric conditions. For example, the hypercortisolemia observed in a subset of patients with depression may have a direct impact on the symptoms of depression, but it is also possible that the hypercortisolemia merely reflects the stress associated with depression. Further, rather than causing depression, hypercortisolemia could represent a homeostatic attempt to overcome glucocorticoid resistance. Each of these possibilities will be considered, and correlational and causal evidence will be reviewed. This article will focus on the relationships between glucocorticoids and psychiatric symptoms in Cushing's syndrome, major depression, and steroid psychosis/steroid dementia, as well as the effects of exogenously administered glucocorticoids in normal volunteers. Similarities and differences in the relationship of glucocorticoid hormones to psychiatric symptoms in these conditions will be reviewed. Possible mediators of glucocorticoid effects on the brain and behavior, as well as possible "pro-aging" effects of glucocorticoids in certain cells of the body, will be reviewed. The article concludes with a conceptual model of glucocorticoid actions in the brain that may lead to novel therapeutic opportunities.

Obesity and polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is one of the most common endocrinopathies in women of fertile age. Obesity is encountered in 30-70% of PCOS-affected women, and its presence significantly modifies both clinical and laboratory expression of the syndrome. Obesity increases the risk of co-morbidities associated with PCOS, such as impaired glucose tolerance and type 2 diabetes mellitus, hyperlipidemia and arterial hypertension. The etiopathogenesis of obesity in PCOS has not yet been exactly clarified. There clearly is a vicious circle of abdominal obesity, insulin resistance, and hyperadrogenemia. Differences in ghrelin and neuropeptide Y levels between PCOS patients and those with simple obesity were also described. Weight loss is the first choice recommendation for the treatment of clinical manifestations of PCOS, such as menstrual cycle irregularities, infertility or hirsutism. However, the best treatment approach in obese PCOS patients remains to be defined. Studies concerning different weight loss regimens, antiobesity drugs, bariatric surgery, insulin sensitizers, and hormonal therapy are reviewed.