Lack of association between type 2 diabetes and major depression: epidemiologic and genetic evidence in a multiethnic population

Association of hyperopia with incident clinically significant depression: epidemiological and genetic evidence in the middle-aged and older population

AIMS

To investigate the association between hyperopia and clinically significant depression (CSD) in middle-aged and older individuals. The effect of genetic determinants of hyperopia on incident CSD was also explored.

METHODS

We included participants who had available data on mean spherical equivalent (MSE) and were free of depression at baseline from the UK Biobank. For the phenotypic association, hyperopia was defined as MSE of+2.00 dioptres (D) or greater, and was divided into mild, moderate and high groups. Diagnosis of CSD across follow-up was determined based on electronic hospital inpatients records. For the genetic association analysis, the association between hyperopia Polygenic Risk Score and incident CSD was assessed. Mendelian randomisation was assessed for causality association.

RESULTS

Over a median follow-up of 11.11 years (IQR: 10.92-11.38), hyperopia was significantly associated with incident CSD independent of genetic risk (HR 1.29, 95% CI 1.05 to 1.59) compared with emmetropia participants, especially in those hyperopic patients without optical correction (HR 1.38, 95% CI 1.07 to 1.76). In addition, participants in the high degree of hyperopia were more likely to have incident CSD than participants in the mild degree of hyperopia (P for trend=0.009). Genetic analyses did not show any significant associations between hyperopia and incident CSD (p≥0.1).

CONCLUSIONS

Hyperopia was significantly associated with an increased risk of incident CSD. This was independent of genetic predisposition to hyperopia, emphasising the importance of regular vision screening and correction of hyperopia to reduce the risk of CSD regardless of genetic risk.

Diabetes mellitus type 2 as an underlying, comorbid or consequent state of mental disorders

Somatic disturbances that occur in parallel with psychiatric diseases are a major challenge in clinical practice. Various factors contribute to the development of mental and somatic disorders. Type 2 diabetes mellitus (T2DM) is a significant health burden worldwide, and the prevalence of diabetes in adults is increasing. The comorbidity of diabetes and mental disorders is very common. By sharing a bidirectional link, both T2DM and mental disorders influence each other in various manners, but the exact mechanisms underlying this link are not yet elucidated. The potential mechanisms of both mental disorders and T2DM are related to immune and inflammatory system dysfunction, oxidative stress, endothelial dysfunction, and metabolic disturbances. Moreover, diabetes is also a risk factor for cognitive dysfunction that can range from subtle diabetes-associated cognitive decline to pre-dementia and dementia. A complex re-lationship between the gut and the brain also represents a new therapeutic approach since gut-brain signalling pathways regulate food intake and hepatic glucose production. The aim of this minireview is to summarize and present the latest data on mutual pathogenic pathways in these disorders, emphasizing their complexity and interweaving. We also focused on the cognitive performances and changes in neurodegenerative disorders. The importance of implementing integrated approaches in treating both of these states is highlighted, along with the need for individual therapeutic strategies.

Effects of metabolic factors in mediating the relationship between Type 2 diabetes and depression in East Asian populations: A two-step, two-sample Mendelian randomization study

BACKGROUND

Observational studies suggested a close link between type 2 diabetes (T2D), metabolic factors and depression, while the causal relationships remained poorly understood.

OBJECTIVE

To determine the causality between T2D and depression, and to investigate the roles of metabolic factors in mediating the relationship between T2D and depression in East Asians.

METHODS

Using summary statistics from the largest and most up-to-date genome-wide association studies of depression (12,588 cases and 85,914 controls) and T2D (36,614 cases and 155,150 controls) among East Asians, two-step and two-sample MR analyses were performed to estimate the causal mediation effects of metabolic factors including lipids profiles, blood pressure (BP) and fasting insulin (FI) on the relationship between T2D and depression.

RESULTS

Genetically predicted T2D was significantly associated with depression (OR [95 % CI]:1.06 [1.01, 1.11], P = 0.043), but not vice versa. T2D was causally associated with lower levels of HDL-C and higher levels of LDL-C, triglycerides (TG), BP and FI. Furthermore, the causal effects of T2D on depression were significantly mediated by LDL-C (β [95 % CI]: -0.003 [-0.005, -0.001], P = 0.007), and suggestively mediated by TG (0.001 [0.001, 0.003], P = 0.049) and FI (0.006 [0.001, 0.012], P = 0.049).

LIMITATIONS

First, depression was defined by several methods, like symptom questionnaires or self-completed surveys. Second, two-sample MR approach is unable to detect the non-linear causal relationships. Third, independent data sets were not available for replication of our findings.

CONCLUSION

T2D was causally associated with the risk of depression, and LDL-C, TG, and FI were potential causal mediators of the effect of T2D on depression. Understanding the causality among T2D, metabolic factors and depression is crucial for identifying potential targets for early intervention.

Genetic and Environmental Contribution to the Co-Occurrence of Endocrine-Metabolic Disorders and Depression: A Nationwide Swedish Study of Siblings

OBJECTIVE

Depression is common in individuals with endocrine-metabolic disorders and vice versa, and a better understanding of the underlying factors contributing to the comorbidity of these disorders is needed. This study investigated the familial coaggregation of depression and endocrine-metabolic disorders and estimated the contribution of genetic and environmental factors to their co-occurrence.

METHODS

This population-based cohort study included 2.2 million individuals born in Sweden between 1973 and 1996, with follow-up through 2013. Participants were linked to their biological parents, allowing identification of full siblings, maternal half siblings, and paternal half siblings. Diagnoses of depression and endocrine-metabolic conditions were investigated, with the latter grouped into autoimmune disorders (autoimmune hypothyroidism, Graves' disease, and type 1 diabetes) and non-autoimmune disorders (type 2 diabetes, obesity, and polycystic ovary syndrome). Logistic regression and Cox regression were used to estimate the associations between endocrine-metabolic disorders and depression within the same individual and across siblings. Quantitative genetic modeling was performed to investigate the relative contribution of genetic and environmental influences.

RESULTS

Individuals with endocrine-metabolic disorders had a significantly higher risk of depression, with odds ratios ranging from 1.43 (95% CI=1.30, 1.57) for Graves' disease to 3.48 (95% CI=3.25, 3.72) for type 2 diabetes. Increased risks extended to full and half siblings. These correlations were mainly explained by shared genetic influences for non-autoimmune conditions, and by nonshared environmental factors for autoimmune disorders, especially for type 1 diabetes.

CONCLUSIONS

These findings provide phenotypic and etiological insights into the co-occurrence of depression and various endocrine-metabolic conditions, which could guide future research aiming at identifying pathophysiological mechanisms and intervention targets.

Antidepressants for depressed patients with type 2 diabetes mellitus: A systematic review and network meta-analysis of short-term randomized controlled trials

This network meta-analysis compared the short-term treatment effects of different antidepressants on depression severity and HbA1c in depressed patients with type 2 diabetes mellitus (T2DM). We searched 8- to 24-week randomized-controlled trials (RCTs) in PubMed, Scopus, Web of Science, Cochrane Central Register of Controlled Trials, and Clinicaltrials.gov on November 22, 2021. We included 12 RCTs (N = 792) studying agomelatine, citalopram, escitalopram, fluoxetine, nortriptyline, no treatment, paroxetine, sertraline, vortioxetine, and placebo. Compared to placebo, the standardized mean differences and 95% confidence intervals (SMD, 95%CIs) for depression severity reduction revealed that escitalopram ranked first (-2.93, -3.92 to -1.94), followed by agomelatine (-0.68, -1.15 to -0.20). Compared to placebo, the mean differences (MDs, 95%CIs) for HbA1c reduction suggested that vortioxetine ranked first (-2.35, -4.13 to -0.57), followed by escitalopram (-1.00, -1.42 to -0.57) and agomelatine (-0.79, -1.16 to -0.42). Limited evidence from short-term trials in depressed patients with T2DM suggests that escitalopram and agomelatine may have a favorable profile in reducing depression and controlling glycemic goals, but more trials are required.

Chy NU, Alam N, Rana MM, Chowdhury NA, Hasan MM. The relationship between medical comorbidities and health-related quality of life among adults with type 2 diabetes: The experience of different hospitals in southern Bangladesh

Objective

Health-related quality of life (HRQoL) is a critical determinant to assess the severity of chronic diseases like diabetes mellitus. It has a close association with complications, comorbidities, and medical aid. This study aimed to estimate the prevalence of medical comorbidities and determine the relationship between comorbidities and HRQoL among type 2 diabetic patients of southern Bangladesh.

Method

This study was a cross-sectional study conducted through face to face interviews using a pre-tested structured questionnaire and by reviewing patient’s health records with prior written consent. The study was conducted on 2,136 patients with type 2 diabetes attending five hospitals of Chattogram, Bangladesh, during the tenure of November 2018 to July 2019. Quality of life was measured using the widely-used index of EQ-5D that considers 243 different health states and uses a scale in which 0 indicates a health state equivalent to death and 1 indicates perfect health status. The five dimensions of the quality index included mobility, self-care, usual activities, pain or discomfort, and anxiety or depression.

Results

Patients with three comorbidities and with four or more comorbidities had a higher probability of reporting “extreme problem” or “some problem” in all five dimensions of the EQ-5D index compared with those without comorbidity (Odds ratio: mobility, 3.99 [2.72–5.87], 6.22 [3.80–10.19]; usual activity, 2.67 [1.76–4.06], 5.43 [3.28–8.98]; self-care, 2.60 [1.65–4.10], 3.95 [2.33–6.69]; pain or discomfort, 2.22 [1.48–3.33], 3.44 [1.83–6.45]; anxiety or depression, 1.75 [1.07–2.88], 2.45 [1.19–5.04]). The number of comorbidities had a negative impact on quality of life.

Conclusion

Prevalent comorbidities were found to be the significant underlying cause of declined HRQoL. To raise diabetes awareness and for better disease management, the exposition of comorbidities in regards to HRQoL of people with diabetes should be considered for type 2 diabetes management schemas.

Shared genetic loci between depression and cardiometabolic traits

Epidemiological and clinical studies have found associations between depression and cardiovascular disease risk factors, and coronary artery disease patients with depression have worse prognosis. The genetic relationship between depression and these cardiovascular phenotypes is not known. We here investigated overlap at the genome-wide level and in individual loci between depression, coronary artery disease and cardiovascular risk factors. We used the bivariate causal mixture model (MiXeR) to quantify genome-wide polygenic overlap and the conditional/conjunctional false discovery rate (pleioFDR) method to identify shared loci, based on genome-wide association study summary statistics on depression (n = 450,619), coronary artery disease (n = 502,713) and nine cardiovascular risk factors (n = 204,402–776,078). Genetic loci were functionally annotated using FUnctional Mapping and Annotation (FUMA). Of 13.9K variants influencing depression, 9.5K (SD 1.0K) were shared with body-mass index. Of 4.4K variants influencing systolic blood pressure, 2K were shared with depression. ConjFDR identified 79 unique loci associated with depression and coronary artery disease or cardiovascular risk factors. Six genomic loci were associated jointly with depression and coronary artery disease, 69 with blood pressure, 49 with lipids, 9 with type 2 diabetes and 8 with c-reactive protein at conjFDR < 0.05. Loci associated with increased risk for depression were also associated with increased risk of coronary artery disease and higher total cholesterol, low-density lipoprotein and c-reactive protein levels, while there was a mixed pattern of effect direction for the other risk factors. Functional analyses of the shared loci implicated metabolism of alpha-linolenic acid pathway for type 2 diabetes. Our results showed polygenic overlap between depression, coronary artery disease and several cardiovascular risk factors and suggest molecular mechanisms underlying the association between depression and increased cardiovascular disease risk.

Genetic association between major depressive disorder and type 2 diabetes mellitus: Shared pathways and protein networks

BACKGROUND

Major depressive disorder (MDD) and type 2 diabetes mellitus (T2DM) are common public health disorders that often co-occur. This study aims to determine whether gene expression profiles from individuals with MDD or T2DM overlap and if there are any functional interconnectivity between identified genes using protein-protein interaction (PPI).

METHODS

The DNA microarray datasets were extracted from the Gene Expression Omnibus. Gene expression dataset GSE98793 from a case-control study of MDD (64 healthy control subjects, 128 patients) and dataset GSE15653 from a case-control study of T2DM (nine controls, nine individuals with T2DM) were used for this secondary and post-hoc analysis. GO enrichment analyses and Reactome pathway enrichment analysis were performed for functional enrichment analyses with the shared genes. PPI networks, PPI clusters and hub genes were performed to detect the potential relationships among differentially expressed genes (DEG) -encoding proteins in both MDD and T2DM.

RESULTS

A total of 3640 DEGs were identified in the MDD group when compared to the control group, whereas 3700 DEGs were identified in the T2DM group when compared to the control groups, among which 244 DEGs were overlap genes. The identified DEGs were enriched for Interleukin-4 and Interleukin-13 signaling, neutrophil degranulation, as well as other select species of the innate immune system. The biological processes of neurofibrillary tangle assembly regulation, tau-protein kinase activity regulation, amyloid-beta clearance regulation, amyloid-beta formation regulation and neuron apoptotic processes were also identified. Molecular function analysis indicated that identified genes were mainly enriched for amyloid-beta binding. 925 out of 1006 protein-protein interactions and six sub-networks were identified reflecting the disparate biological domains of overlapping genes. Ten hub genes further highlight the putative importance of tau-protein kinase activity, inflammatory response and neuron apoptotic regulatory processes across MDD and T2DM.

CONCLUSIONS

Our results indicate that an overlapping genetic architecture subserves MDD and T2DM. Genes relevant to the innate immune system, tau protein formation, and cellular aging were identified. Results indicate that the common, often comorbid, conditions of MDD and T2DM have a pathoetiologic nexus.

Risk of Depression among Early Onset Type 2 Diabetes Mellitus Patients

<b><i>Methodology:</i></b> Biochemically confirmed type 2 diabetes mellitus (T2DM) patients (<i>n</i> = 1,114) were recruited from the outpatient department of 2 tertiary care hospitals in Dhaka, Bangladesh. Face-to-face interview was conducted using a semi-structured questionnaire containing sociodemographic parameters and relevant information about depression and diabetes. Biochemical test results and treatment-related information were taken from patients’ records. The Hospital Anxiety and Depression Scale (HADS) was used to screen all patients for psychiatric manifestation. Those diagnosed by HADS were subsequently reassessed using structured clinical interview for DSM-5 Disorders – Clinician Version. T2DM diagnosed at age &#x3c;40 years were considered as early onset T2DM. Association between age of onset category and depression was assessed using multivariable mixed-effect logistic regression adjusting for random variation of the area of residence and plausible confounders. <b><i>Results:</i></b> Around a third of the participants (32.5%) were diagnosed with T2DM before the age of 40 years. Early onset T2DM patients were found to have 57% increase in the risk of developing depression (OR 1.57; 95% CI 1.13–2.28; <i>p</i> = 0.011) in comparison to those with usual onset T2DM (≥40 years). Among other factors a positive family history for diabetes (OR 1.33; 95% CI 1.03–1.78; <i>p</i> = 0.038), poor glycemic control (OR 1.31; 95% CI 1.03–1.68; <i>p</i> = 0.028), presence of 1, or more diabetic complications (OR 1.37; 95% CI 1.03–1.78; <i>p</i> = 0.011) also showed increased risk of depression. <b><i>Conclusion:</i></b> Early onset T2DM patients are at greater risk of developing depression. The finding is likely to help in setting preventive strategies aiming to reduce the presence of concomitant depression symptoms among diabetes.

Understanding the relationship between type 2 diabetes and depression: lessons from genetically informative study designs

AIMS

To conduct a systematic review in order to comprehensively synthesize the findings from a diverse range of genetically informative studies on comorbid depression and type 2 diabetes.

METHODS

Database searches (1 January 2008 to 1 June 2020) in PubMed and EMBASE were conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Eligible reports employed any type of genetically informed design, including twin modelling, Mendelian randomization, genome-wide association studies, polygenetic risk scores, or linkage disequilibrium score regression. Searches generated 451 unique citations, and 16 manuscripts met the inclusion criteria.

RESULTS

The included studies addressed three aetiological models of the depression-diabetes relationship: uni- or bi-directional phenotypic causation; shared genetic liability; or gene-environment interaction. From these studies, there is modest evidence that type 2 diabetes is causally related to risk of developing depression, but much more limited evidence that depression is causally related to risk of diabetes. There is little evidence of shared genetic liability between depression and diabetes or of gene-environment interaction.

CONCLUSIONS

Findings from genetically informed studies are mixed but provide some support for the uni- or bi-directional phenotypic model of depression and type 2 diabetes. Future studies should also explore the hypothesis that this relationship may be influenced by shared environmental risk factors. Findings can inform multifaceted approaches to diabetes prevention and care that reflect how psychosocial factors contribute to type 2 diabetes risk and outcomes.

Depressive symptoms are not associated with type 2 diabetes in a rural population in China: findings from the Henan rural cohort

BACKGROUND

Depression is one of the most prevalent mental health challenges that affect all groups of persons. This study examines the association between type 2 diabetes and depressive symptoms (using PHQ-2) in a rural population. Other risk factors of depressive symptoms are examined.

METHODS

Data from 30,001 participants from the Henan rural cohort was analyzed. Multivariable logistic regression analyses were performed to examine the associations between depressive symptoms (DS) and type 2 diabetes and other risk factors. Adjusted odds ratios (aOR) with confidence intervals (CI) at 95% are reported.

RESULTS

The prevalence of DS in the study population is 5.86%, 6.69% in women, 4.74% in men, 5.80% in persons without diabetes and 6.81% in persons with diabetes (diagnosed and undiagnosed). DS prevalence was highest in persons with previously diagnosed diabetes (8.27%). No association was found between DS and diabetes (aOR = 0.95, CI at 95% 0.61-1.48; p=0.836). DS was associated with poor glycemic control (aOR=1.43, CI at 95% 1.04- 1.98; p= 0.034) in persons with previously diagnosed diabetes, persons with elevated triglycerides (aOR=1.19, CI at 95% 1.08-1.30; p<0.001), household income (aOR= 0.78, CI at 95% 0.63-0.97; p=0.027), marital status (aOR=1.37, CI at 95% 1.01-1.88, p=0.049) and hypertension treatment with medication (aOR=1.94, CI at 95% 1.48-2.55; p<0.001).

LIMITATIONS

DS was assessed through self-report and may suffer recall or information bias.

CONCLUSIONS

DS was not associated with diabetes in our study population. The association between poor glycemic control and DS calls for the integration of screening for depression among patients with diabetes.

Comorbid depression in medical diseases

Depression is one of the most common comorbidities of many chronic medical diseases including cancer and cardiovascular, metabolic, inflammatory and neurological disorders. Indeed, the prevalence of depression in these patient groups is often substantially higher than in the general population, and depression accounts for a substantial part of the psychosocial burden of these disorders. Many factors can contribute to the occurrence of comorbid depression, such as shared genetic factors, converging biological pathways, social factors, health behaviours and psychological factors. Diagnosis of depression in patients with a medical disorder can be particularly challenging owing to symptomatic overlap. Although pharmacological and psychological treatments can be effective, adjustments may need to be made for patients with a comorbid medical disorder. In addition, symptoms or treatments of medical disorders may interfere with the treatment of depression. Conversely, symptoms of depression may decrease adherence to treatment of both disorders. Thus, comprehensive treatment plans are necessary to optimize care.

Association between depressive symptoms and arterial stiffness: a cross-sectional study in the general Chinese population

OBJECTIVES

To determine the independent relationship between depressive symptoms and arterial stiffness in the general Chinese population, and to explore possible interactive factors in the relationship.

DESIGN

A cross-sectional study.

SETTING AND PARTICIPANTS

Consecutive participants who received routine health physical examination in an affiliated hospital of a comprehensive university in Hunan Province, China, between September 2013 and March 2014 were examined. After exclusion of subjects not meeting the criteria, a total of 1334 subjects aged 22-77 years were recruited for final analysis.

MEASURES

The Patient Health Questionnaire-9 was employed to assess the degree of depressive symptoms: 0-4 no depressive symptoms, 5-9 mild depressive symptoms and 10-27 moderate to severe depressive symptoms. Brachial-ankle pulse wave velocity (baPWV) was measured to determine arterial stiffness.

RESULTS

There was a slight increase in baPWV across elevated degrees of depressive symptoms (p=0.025). Multivariate linear regression analysis revealed that mild depressive symptoms and moderate to severe depressive symptoms were independently associated with baPWV compared with no depressive symptoms after adjusting for baseline confounders (beta-coefficient: 40.3, 95% CI 6.6 to 74.1; beta-coefficient: 87.7, 95% CI 24.0 to 151.5, respectively). Further stratified analyses indicated that the relationship between degree of depressive symptoms and baPWV was predominant in subjects who had normal or normal-high blood pressure, or combined with hypertension (p for interaction=0.016), or in subjects with diabetes mellitus (p for interaction=0.004), examined in multivariate linear regressions. In addition, after adjustment, a significant association between moderate to severe depressive symptoms and baPWV was also found in female subjects younger than 60 years, although the interactive effect was not significant (p for interaction=0.056).

CONCLUSIONS

Depressive symptoms are independently associated with arterial stiffness, especially in subjects whose blood pressures are beyond the optimal range and combined with diabetes mellitus.

Genetic Overlap Between Type 2 Diabetes and Depression in a Sri Lankan Population Twin Sample

OBJECTIVE

Results from twin studies examining the genetic overlap between type 2 diabetes and depression are currently inconclusive. This question has not been addressed in non-Western populations. We aimed to examine whether there are common genetic factors between type 2 diabetes and depression in a Sri Lankan population using genetic model-fitting analysis.

METHOD

The Colombo Twin and Singleton Study-Phase 2 consists of 2019 singletons, and 842 monozygotic and 578 dizygotic twin pairs. The primary outcomes were self-reported type 2 diabetes diagnosis and Beck Depression Inventory scores. Standard bivariate twin models were fitted to estimate the genetic and environmental (co)variance of type 2 diabetes and depression.

RESULTS

In the best-fitting model, the phenotypic correlation between type 2 diabetes and depression was significant in female individuals only (r = 0.15 [0.08-0.21]). This association was primarily attributed to a significant genetic correlation between the traits (rA = 0.53 [0.19-0.98]).

CONCLUSIONS

In female individuals, but not male individuals, we found a significant genetic overlap between type 2 diabetes and depression in the context of a modest phenotypic correlation.

Effects of variants of 50 genes on diabetes risk among the Chinese population born in the early 1960s

BACKGROUND

Genome-wide association studies have identified loci that significantly increase diabetes risk. This study explored the genetic susceptibility in relation to diabetes risk in adulthood among a Chinese population born in the early 1960s.

METHODS

In all, 2129 subjects (833 males, 1296 females) were selected from the cross-sectional 2010 to 2012 China National Nutrition and Health Survey. Fifty diabetes-related single nucleotide polymorphisms (SNPs) were detected. Two diabetes genetic risk scores (GRSs) based on the 50 diabetes-predisposing variants were developed to examine the association of these SNPs with diabetes risk.

RESULTS

Associations were found between diabetes risk and SNPs in the MTNR1B (rs10830963), KLHDC5 (rs10842994), GRK5 (rs10886471), cyclindependentkinase 5 regulatory subunit associated protein 1 (rs10946398), adaptorrelated protein complex 3 subunit sigma 2 (rs2028299), diacylglycerol kinase beta/transmembrane protein 195 (rs2191349), SREBF chaperone (rs4858889), ankyrin1 (rs516946), RAS guanyl releasing protein 1 (rs7403531), and zinc finger AN1-type containing 3 (rs9470794) genes. As a continuous variable, with a 1-point increase in the GRS or weighted (w) GRS, fasting plasma glucose (FPG) increased 0.045 and 0.044 mM, respectively (P < 0.001 for both), after adjusting for confounders. Both GRS and wGRS showed an association with diabetes, with a multivariable-adjusted odds ratio (95% confidence interval) of 1.09 (1.00-1.19) and 1.12 (1.03-1.22), respectively, among all subjects. No significant associations were found between the GRS or wGRS and impaired fasting glucose or impaired glucose tolerance.

CONCLUSIONS

The data suggest the association of 10 SNPs and the GRS or wGRS with diabetes risk. Genetic susceptibility to diabetes may synergistically affect the risk of diabetes in adulthood.

Diabetes and depression were not associated in Venezuelan adults: The EVESCAM study, a national cross-sectional sample

BACKGROUND

Evidence suggests that depression is more common in patients with diabetes than in the general population. However, contradictory results expose controversy in this association.

OBJECTIVE

To evaluate the relationship between diabetes and depression in a national sample of Venezuelan adults.

METHODS

The EVESCAM was a national population-based, cross-sectional, randomized cluster sampling study, which assessed 3,454 adults from July 2014 to January 2017 (response rate of 77.3%). Diabetes was defined using fasting blood glucose and a 2-hour oral glucose tolerance test. Depressive symptoms were determined using the Hospital Anxiety and Depression Scale.

RESULTS

3255 subjects were assessed. Depressive symptom score was different between genders and among age groups (p<0.001), and similar in those subjects with or without diabetes (p=0.899). Depressive symptoms prevalence was higher in women than in men and increased with age (p<0.05), but was similar in those with and without diabetes (p=0.215). Using a multivariate regression analysis model, the association of depressive symptoms and diabetes remains non-significant after adjusting for age and gender (Odds ratio=0.98; 95% Confidence Intervals 0.95 - 1.02, p=0.504).

CONCLUSION

Diabetes and depression were not associated in a large sample of Venezuelan adults.

The prevalence of comorbid depression in patients with type 2 diabetes: an updated systematic review and meta-analysis on huge number of observational studies

AIMS

Depression is a common co-morbidity in patients with type 2 diabetes mellitus (T2DM). Untreated depression in these patients adversely affects self-care activities and other diabetes complications. The aim of this study is to estimate the prevalence of depression among patients with T2DM by conducting a meta-analysis of observational studies.

METHODS

MEDLINE, Web of Science, Science Direct, and Google Scholar databases were searched for all observational studies that assessed depression in T2DM. Relevant articles were searched using the combination of Medical Subject Heading (MeSH) terms of "depression", "depressive disorder", and "diabetes mellitus" published between January 2007 and July 2018. Random effects model was used to estimate the weighted prevalence rates and 95% CI using "metaprop program in STATA 11".

RESULTS

In total, the 248 included studies (with 273 reported prevalence) identified 83,020,812 participants; of them, 23,245,827 (28%; 95% CI 27, 29) suffered from different severity levels of depressive disorders. The prevalence of depression was separately reported in 137,372 males and 134,332 females. Of them, 31,396 males (23%, 95% CI: 20, 26) and 45,673 females (34%, 95% CI: 31, 38) were depressed. Compared with global estimate, depression prevalence was lower in Europe (24%) and Africa (27%), but higher in Australia (29%) and Asia (32%). The prevalence in America was equal to the estimated prevalence in the world (28%). Depression was more common in subjects younger than 65 compared with elderlies (31% vs. 21%).

CONCLUSION

Our findings demonstrated that almost one in four adults with T2DM experienced depression. Given the high prevalence of depressive disorders in diabetic patients, screening these patients for co-morbid depression and its relevant risk factors is highly recommended.

Risk of Depression and Suicidality among Diabetic Patients: A Systematic Review and Meta-Analysis

The purpose of this study is to conduct a systematic review and meta-analysis to evaluate the risk of depression and suicidality among diabetic patients.

METHODS

Medline, PubMed, EMBASE, Cochrane library, and Psych INFO were searched for studies published from 2008 onwards. Meta-analysis was conducted to estimate the pooled effect size. Sources of heterogeneity were investigated by subgroup analysis and meta-regression.

RESULTS

In total, 5750 articles were identified and of those, 17 studies on suicidality and 36 on depression were included in this study. Our analysis suggests a positive relationship between diabetes and depression (cohort studies odds ratio (OR) 1.49, 95% confidence interval (CI): 1.36⁻1.64 and cross-sectional studies OR 2.04, 95% CI, 1.73⁻2.42). Pooled OR values for suicidal ideation, attempted suicide, and completed suicide were 1.89 (95% CI: 1.36⁻2.63), 1.45 (95% CI: 1.07⁻1.96), and 1.85 (95% CI: 0.97⁻3.52), respectively. All findings were statistically significant except for completed suicide.

CONCLUSIONS

The increased risk of depression and suicidality in diabetic patients highlights the importance of integrating the evaluation and treatment of depression with diabetes management in primary healthcare settings. Further research in this area is needed.

The Bidirectional Relationship between Diabetes and Depression: A Literature Review

Diabetes is a major public health problem worldwide. Depression is a serious mental condition that decreases mental and physical functioning and reduces the quality of life. Several lines of evidence suggest a bidirectional relationship between diabetes and depression: diabetes patients are twice as likely to experience depression than nondiabetic individuals. In contrast, depression increases the risk of diabetes and interferes with its daily self-management. Diabetes patients with depression have poor glycemic control, reduced quality of life, and an increased risk of diabetes complications, consequently having an increased mortality rate. Conflicting evidence exists on the potential role of factors that may account for or modulate the relationship between diabetes and depression. Therefore, this review aims to highlight the most notable body of literature that dissects the various facets of the bidirectional relationship between diabetes and depression. A focused discussion of the proposed mechanisms underlying this relationship is also provided. We systematically reviewed the relevant literature in the PubMed database, using the keywords “Diabetes AND Depression”. After exclusion of duplicate and irrelevant material, literature eligible for inclusion in this review was based on meta-analysis studies, clinical trials with large sample sizes (n≥1,000), randomized clinical trials, and comprehensive national and cross-country clinical studies. The evidence we present in this review supports the pressing need for long, outcome-oriented, randomized clinical trials to determine whether the identification and treatment of patients with these comorbid conditions will improve their medical outcomes and quality of life.

Markers of DNA/RNA damage from oxidation as predictors of a registry-based diagnosis of psychiatric illness in type 2 diabetic patients

Oxidative stress is a potential biological mediator of the higher rates of psychiatric illness (PI) observed after the onset of type 2 diabetes (T2DM). We investigated validated urinary markers of systemic DNA/RNA damage from oxidation (8-oxodG/8-oxoGuo respectively) as predictors of incident PI in a cohort of 1381 newly diagnosed T2DM patients, who were followed prospectively for a total of 19 years after diagnosis. Psychiatric diagnoses were from Danish national registries. Patients were examined at the time of diagnosis and at a 6-year follow-up. At baseline, 8-oxodG was slightly lower in PI vs. non-PI patients, while at 6-year follow-up, 8-oxoGuo was significantly higher in PI patients. Using Cox proportional hazard models, we found that higher levels of 8-oxodG at 6-year follow-up significantly predicted lower incidence of PI after the adjustment for confounders. In a subgroup analysis, this association was most predominant in minor PIs (unipolar depression and anxiety) compared to major PIs such as schizophrenia and bipolar disorder. These observations indicate that higher levels of systemic oxidative stress are not associated with a higher risk of PI after T2DM onset. Only PI patients treated in hospital care were included in the registries, and the conclusion thus only applies to these individuals.

Prospective associations of depression subtypes with cardio-metabolic risk factors in the general population

The mechanisms and temporal sequence underlying the association between major depressive disorder (MDD) and cardio-metabolic diseases are still poorly understood. Recent research suggests subtyping depression to study the mechanisms underlying its association with biological correlates. Accordingly, our aims were to (1) assess the prospective associations of the atypical, melancholic and unspecified subtypes of MDD with changes of fasting glucose, high-density lipoprotein-cholesterol, triglycerides, systolic blood pressure and the incidence of the metabolic syndrome, (2) determine the potential mediating role of inflammatory marker or adipokine concentrations, eating behaviors and changes in waist circumference during follow-up. Data stemmed from CoLaus|PsyCoLaus, a prospective cohort study including 35-66-year-old randomly selected residents of an urban area. Among the Caucasian participants who underwent the physical and psychiatric baseline evaluations, 2813 (87% participation rate) also accepted the physical follow-up exam (mean follow-up duration=5.5 years). Symptoms of mental disorders were elicited using a semi-structured interview. The atypical MDD subtype, and only this subtype, was prospectively associated with a higher incidence of the metabolic syndrome (OR=2.49; 95% CI 1.30-4.77), a steeper increase of waist circumference (β=2.41; 95% CI 1.19-3.63) and independently of this, with a steeper increase of the fasting glucose level (β=131; 95% CI 38-225) during follow-up. These associations were not attributable to or mediated by inflammatory marker or adipokine concentrations, eating behaviors, comorbid psychiatric disorders or lifestyle factors. Accordingly, our results further support the subtyping of MDD and highlight the particular need for prevention and treatment of metabolic consequences in patients with atypical MDD.

Influence of depression on genetic predisposition to type 2 diabetes in a multiethnic longitudinal study

We assessed the association between depression status and prevalent and incident type 2 diabetes (T2D) as well as the interaction between depression and a genetic risk score (GS) based on 20 T2D single-nucleotide polymorphisms (SNPs) in a multi-ethnic longitudinal study. We studied 17,375 participants at risk for dysglycemia. All participants had genotypic and phenotypic data collected at baseline and 9,930 participants were followed-up for a median of 3.3 years. Normal glucose tolerance (NGT), impaired fasting glucose (IFG)/impaired glucose tolerance (IGT) and T2D statuses were determined using an oral glucose tolerance test and the 2003 American Diabetes Association criteria. Depression was diagnosed at baseline using Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM IV). Multivariate logistic regression models were adjusted for age, sex, ethnicity and body-mass index and an interaction term GS X depression was added to the model. After appropriate Bonferroni correction, no significant association between depression and T2D-related traits (IFG/IGT, T2D and dysglycemia), and no significant interaction between the GS and depression status was observed at baseline or follow-up. Our longitudinal data do not support an association between depression and abnormal glycemic status. Moreover, depression does not modify the effect of T2D predisposing gene variants.

Investigating shared aetiology between type 2 diabetes and major depressive disorder in a population based cohort

Type II diabetes (T2D) and major depressive disorder (MDD) are often co-morbid. The reasons for this co-morbidity are unclear. Some studies have highlighted the importance of environmental factors and a causal relationship between T2D and MDD has also been postulated. In the present study we set out to investigate the shared aetiology between T2D and MDD using Mendelian randomization in a population based sample, Generation Scotland: the Scottish Family Health Study (N = 21,516). Eleven SNPs found to be associated with T2D were tested for association with MDD and psychological distress (General Health Questionnaire scores). We also assessed causality and genetic overlap between T2D and MDD using polygenic risk scores (PRS) assembled from the largest available GWAS summary statistics to date. No single T2D risk SNP was associated with MDD in the MR analyses and we did not find consistent evidence of genetic overlap between MDD and T2D in the PRS analyses. Linkage disequilibrium score regression analyses supported these findings as no genetic correlation was observed between T2D and MDD (rG = 0.0278 (S.E. 0.11), P-value = 0.79). As suggested by previous studies, T2D and MDD covariance may be better explained by environmental factors. Future studies would benefit from analyses in larger cohorts where stratifying by sex and looking more closely at MDD cases demonstrating metabolic dysregulation is possible. © 2016 The Authors. American Journal of Medical Genetics Part B: Neuropsychiatric Genetics Published by Wiley Periodicals, Inc.

Incidence of Depression and Associated Factors in Patients With Type 2 Diabetes in Quebec, Canada: A Population-Based Cohort Study

It has been reported that the risk of depression is higher among people with type 2 diabetes compared with a nondiabetic population. Among diabetic patients, depression has been associated with worse self-care behaviors, poor glycemic control, and an increased risk of diabetes complications. Identifying factors associated with the occurrence of depression may help physicians identify earlier diabetic patients at a high risk of developing depression, improve prevention, and accelerate proper treatment. To our knowledge, very few population-based studies have reported on the incidence of clinically diagnosed depression as a consequence of type 2 diabetes over a long follow-up period. The objective of this study was to estimate the incidence of clinically diagnosed depression among type 2 diabetic patients newly treated with oral antidiabetic drugs (ADs) and to identify factors associated with the occurrence of depression.Administrative claims data from the public health insurance plan were used to identify a cohort of new oral AD users aged ≥18 years between 2000 and 2006. Patients were followed from oral AD treatment initiation until the diagnosis of depression, ineligibility for the public drug plan, death, or the end of the study, whichever came first. Incidence rates were determined using person-time analysis. Factors associated with depression were identified using multivariable Cox regression analysis.We identified 114,366 new oral AD users, of which 4808 had a diagnosis of depression. The overall incidence rate of depression was 9.47/1000 person-years (PYs) (10.72/1000 PYs for women and 8.27/1000 PYs for men). The incidence of depression was higher during the year after oral AD treatment initiation. Independent factors associated with depression included having had mental disorders other than depression, hospitalization, a higher number of different drugs taken and of physicians visited during the year before oral AD initiation. Moreover, we observed a statistically significant age-by-socioeconomic status interaction.The incidence of diagnosed depression is higher during the first year after oral AD treatment initiation. Clinicians could pay particular attention to women, patients starting an AD at a young age, those with a low socioeconomic status, and especially those with a history of anxiety or dementia.

Duration of diabetes and its association with depression in later life: The Health In Men Study (HIMS)

OBJECTIVE

To examine if diabetes and duration of diabetes are direct or indirect causes of depression in later life.

RESEARCH DESIGN AND METHODS

Cross-sectional study of a community-derived sample of 5462 men aged 70-89 years. Men with 'current depression' scored 7 or more on the abbreviated Geriatric Depression Scale (GDS-15), whereas men with 'ever depression' were either currently depressed or reported history or treatment for past depression. The presence of diabetes was established by self-reported history, fasting glucose ≥7 mmol/L (126 mg/dL), or use of insulin or hypoglycemic drugs. Duration of diabetes relied on self-report. Other measured factors included age, place of birth, education, smoking history, and the FRAIL scale.

RESULTS

Diabetes was associated with increased odds ratio (OR) of ever (OR=1.49, 95%CI=1.25, 1.76) and current depression (OR=1.94, 95%CI=1.15, 2.48). The association between duration of diabetes and risk of current depression was 'J-shaped' with odds ratios of 1.92 (95%CI=1.44, 2.54), 1.56 (95%CI=0.89, 2.75), 2.49 (95%CI=1.16, 5.32) and 3.13 (95%CI=1.28, 7.63) for <10, 10-19.9, 20-29.9 and ≥30 years of diabetes history compared with older men without diabetes. The strength of these associations was attenuated after the analyses were adjusted for other measured factors, but the shape of the curve did not change. Structural equation modeling showed that frailty mediated some of the association between diabetes duration and depression (about 15%) and was a strong predictor of depression in the sample.

CONCLUSIONS

In older men, the association between time lived with the diagnosis of diabetes and the risk of depression is 'J-shaped'. Frailty mediates some of the association between diabetes and depression, although other unmeasured factors are also likely to play a role. The introduction of strategies that are effective at decreasing diabetes-related complications may also contribute to decrease the risk of depression among older men.

The association between Diabetes mellitus and Depression

Depression occurrence is two to three times higher in people with diabetes mellitus, the majority of the cases remaining under-diagnosed. The purpose of this review was to show the links between depression and diabetes, point out the importance of identifying depression in diabetic patients and identify the possible ways to address both diseases. Possible common pathophysiological mechanisms as stress and inflammation were explained, while emphasis was made on screening for depression in diabetic patients. An important aspect for the diabetic specialist would be the understanding of the common origins of diabetes and depression and the awareness of this quite common comorbidity, in order to improve the outcomes of both diseases.

ABBREVIATIONS

DALYS = disability adjusted life years, DSM-5 = American Psychiatric Association Diagnostic and Statistical Manual of Mental Disorders, DM1 = Type 1 diabetes mellitus, DM2 = Type 2 diabetes mellitus, HPA-axis = hypothalamus - pituitary - adrenal axis, SNS = sympathetic nervous system, BDI = Beck Depression Inventory, CES-D = Centre for Epidemiologic Studies Depression Scale, HADS = Hospital Anxiety and Depression Scale, PHQ = Patient Health Questionnaire.