Trends in the prevalence of depression in hospitalized patients with type 2 diabetes in Spain: analysis of hospital discharge data from 2001 to 2011

Prevalence of comorbid depression and associated factors among hospitalized patients with type 2 diabetes mellitus in Hunan, China

BACKGROUND

Depression and diabetes are major health challenges, with heavy economic social burden, and comorbid depression in diabetes could lead to a wide range of poor health outcomes. Although many descriptive studies have highlighted the prevalence of comorbid depression and its associated factors, the situation in Hunan, China, remains unclear. Therefore, this study aimed to identify the prevalence of comorbid depression and associated factors among hospitalized type 2 diabetes mellitus (T2DM) patients in Hunan, China.

METHODS

This cross-sectional study involved 496 patients with T2DM who were referred to the endocrinology inpatient department of Xiangya Hospital affiliated to Central South University, Hunan. Participants' data on socio-demographic status, lifestyle factors, T2DM-related characteristics, and social support were collected. Depression was evaluated using the Hospital Anxiety and Depression Scale-depression subscale. All statistical analyses were conducted using the R software version 4.2.1.

RESULTS

The prevalence of comorbid depression among hospitalized T2DM patients in Hunan was 27.22% (95% Confidence Interval [CI]: 23.3-31.1%). Individuals with depression differed significantly from those without depression in age, educational level, per capita monthly household income, current work status, current smoking status, current drinking status, regular physical activity, duration of diabetes, hypertension, chronic kidney disease, stroke, fatty liver, diabetic nephropathy, diabetic retinopathy, insulin use, HbA1c, and social support. A multivariable logistic regression model showed that insulin users (adjusted OR = 1.86, 95% CI: 1.02-3.42) had a higher risk of depression, while those with regular physical activity (adjusted OR = 0.48, 95% CI: 0.30-0.77) or greater social support (adjusted OR = 0.20, 95% CI: 0.11-0.34) had a lower risk of depression. The area under the curve of the receiver operator characteristic based on this model was 0.741 with a sensitivity of 0.785 and specificity of 0.615.

CONCLUSIONS

Depression was moderately prevalent among hospitalized T2DM patients in Hunan, China. Insulin treatment strategies, regular physical activity, and social support were significantly independently associated with depression, and the multivariable model based on these three factors demonstrated good predictivity, which could be applied in clinical practice.

Are adults diagnosed with type 2 diabetes at a greater risk of developing depression? Integrative literature review

BACKGROUND

The aim of this integrative literature review was to investigate the prevalence of depression in adults diagnosed with type 2 diabetes within Europe and to examine the link between adults with type 2 diabetes and the risk of developing depression.

METHODS

An integrative literature review using the databases CINAHL, Medline and PsycInfo to retrieve the most relevant articles on adults with type 2 diabetes and the risk of developing depression.

RESULTS

Gender, age and socio-economic status may increase the risk of an adult with type 2 diabetes developing depression.

CONCLUSION

Adults with type 2 diabetes are at a greater risk of developing depression, and factors such as age, gender and socio-economics also play a role in predicting whether a person with type 2 diabetes will develop depression. Screening tools such as Patient Health Questionnaire-2 (PHQ-2) may be used to assess for depression within GP surgeries at the time of diagnosis with type 2 diabetes.

The economic burden of anxiety and depression on the working age population with diabetes in Spain

Diabetes mellitus (DM) is a complex, chronic, multifactorial, and costly health problem representing 8% of total public health expenditures in Spain. The objective of this study was to analyse the prevalence and costs of Anxiety (AX) and Depression (DP) in the Spanish working population with DM. Data were obtained from the National Health Survey of Spain 2017. A multivariate analysis was conducted to predict the use of resources and absenteeism/presenteeism. Direct and indirect costs were calculated. The final population analysed contained 15,822 subjects (18-65 years old). DM prevalence was 4.8%, and AX-DP 10.6% (50.5% were men). Self-diagnosed health was rated as regular, poor or very poor in 89% of DM subjects with DP-AX. The average costs estimated were €24,643.41 for DM subjects with AX-DP and €20,059.53 for those with only DM. The total estimated 2017 economic impact of DM was 2.4% of Spanish gross domestic product (13% directly related to DP-AX). Indirect costs represented 72.7% of total DP-AX costs. Spanish society is paying a considerable price for the incidence of DP-AX levels with DM in the working population. This global challenge has important repercussions for individuals' quality of life, health systems, and countries' development and economic growth.

Characterizing Multimorbidity from Type 2 Diabetes: Insights from Clustering Approaches

Patients with type 2 diabetes mellitus (T2DM) often live with and develop multiple co-occurring conditions, namely multimorbidity, with diffuse impacts on clinical care and patient quality of life. However, literature characterizing T2DM-related multimorbidity patterns is limited. This review summarizes the findings from the emerging literature characterizing and quantifying the association of T2DM with multimorbidity clusters. The authors' findings reveal 3 dominant cluster types appearing in patients with T2DM-related multimorbidity, such as cardiometabolic precursor conditions, vascular conditions, and mental health conditions. The authors recommend that holistic patient care centers around early detection of other comorbidities and consideration of wider risk factors.

High-fat diet-induced obesity primes fatty acid β-oxidation impairment and consequent ovarian dysfunction during early pregnancy

Background

Obesity is associated with many adverse effects on female fertility. Obese women have a higher likelihood of developing ovulatory dysfunction due to dysregulation of the hypothalamic-pituitary-ovarian axis. However, the effect of obesity on ovarian function during early pregnancy needs to be further assessed.

Methods

C57BL6/J mice were given a high-fat diet (HFD) for 12 weeks to induce obesity. An in vitro high-fat model was established by treating the human ovarian granulosa cell line KGN with oleic acid and palmitic acid. Ovarian morphology of obese mice in early pregnancy was assessed by hematoxylin and eosin staining and ovarian function was assessed by enzyme-linked immunosorbent assay, western blotting, and immunohistochemistry. Oil Red O staining and transmission electron microscopy were used to detect fatty acid accumulation. Specific markers relating to the ovarian functional mechanism were assessed by real-time PCR, western blotting, lactate detection, adenosine triphosphate (ATP) detection, biochemical analyses, and enzyme-linked immunosorbent assay.

Results

The results of this study showed that during early pregnancy, the number of corpus lutea, serum estradiol and progesterone levels, and the expression of the steroid biosynthesis-related protein CYP19A1 (aromatase), CYP11A1 (cholesterol side chain cleavage enzyme), and StAR (steroidogenic acute regulatory protein), were significantly increased in HFD mice. Mice fed an HFD also showed a significant increase in ovarian lipid accumulation on day 7 of pregnancy. Genes involved in fatty acid synthesis (Acsl4 and Elovl5), and fatty acid uptake and transport (Slc27a4), together with the β-oxidation rate-limiting enzyme Cpt1a, were significantly upregulated in HFD mice. Specifically, there was abnormal elevation of ATP and aberrant expression of tricarboxylic acid cycle (TCA)- and electron transport chain (ETC)-related genes in the ovaries of pregnant HFD mice. KGN cells treated with etomoxir targeting β-oxidation of fatty acid showed decreased TCA cycle and ETC related gene expression. The elevation of ATP and estradiol and progesterone levels was reversed.

Conclusions

During early pregnancy, HFD-induced obesity increases fatty acid β-oxidation, which in turn increases TCA cycle and ETC related gene expression, leading to increased ATP production and ovarian dysfunction.

The relationship between depression and metabolic control parameters in type 2 diabetic patients: A cross-sectional and feasibility interventional study

BACKGROUND

Substantial evidence supports a bidirectional relationship between diabetes and clinical depression. However, little is known about the effect of treating one condition on the control of the other. Thus, this study aimed to determine the prevalence of depression among Type II diabetes mellitus (T2DM) patients and to assess the efficacy and feasibility of escitalopram treatment of depression on their metabolic control parameters.

METHODS

T2DM patients attending primary care clinics in the North of Jordan were enrolled in a cross-sectional study during the period from February to December 2019 (n = 157). Depressive symptoms were screened utilising the patient health questionnaire-9 (PHQ-9) tool. Metabolic control was assessed by measurement of glycated haemoglobin (HbA1c), triglycerides, cholesterol, low-density lipoprotein (LDL) and high-density lipoprotein (HDL). Patients with moderate to severe depressive symptoms by PHQ-9 (n = 58) were interviewed by a psychiatrist to confirm a clinical diagnosis of depression. Eligible depressed patients were administered escitalopram 10 mg orally once daily for 3 months (n = 12). Thereafter, depressive symptoms and metabolic control measures were reassessed.

RESULTS

The prevalence of moderate to severe depressive symptoms among T2DM patients, according to PHQ-9, was 36.94%, while the prevalence of clinical depression based on interview was 7.64%. Baseline PHQ-9 scores correlated significantly with baseline levels of HbA1c, HDL, cholesterol and triglycerides. Escitalopram treatment intervention resulted in significant improvement of PHQ-9 scores without significantly improving any of the metabolic control measures.

CONCLUSION

The relationship between depression and T2DM in the context of metabolic syndrome is plausible. However, our results show that escitalopram treatment may not be associated with significant improvement in metabolic control parameters among these patients. Our study has laid the groundwork for future randomised clinical trials with larger sample size and longer follow-up.

Depression and Its Associated Factors among Diabetes Mellitus Patients Attending Selected Hospitals in Southwest Ethiopia: A Cross-Sectional Study

BACKGROUND

Diabetes mellitus and depression are very common diseases worldwide, and the prevalence rates of both conditions are increasing rapidly. Depression among patients with diabetes mellitus results in poor glycemic control through different mechanisms. Besides, the coexistence of a chronic medical illness with depression reduces the probability of recognizing and treating depression. The study is aimed at assessing the prevalence and factors associated with depression among adults with diabetes mellitus.

METHODS

A hospital-based cross-sectional study was conducted among adult diabetes mellitus patients on follow-up in Mizan-Tepi University Teaching Hospital and Tepi General Hospital. A consecutive sampling technique was employed to recruit the study participants, and data were collected through face-to-face interview and medical chart review. Depression was measured using Patient Health Questionnaire-nine (PHQ-9). Binary logistic regression analysis was done and a p value of less than 0.05 was used as a level of significance.

RESULTS

The prevalence of depression among study participants was 37.0% (95% CI 32.0%-42.0%). The majority (44.7%) of the patients had mild depression, while only 2% had severe depression. Being male (AOR = 1.92, 95% CI: 1.15-3.22), urban residence (AOR = 3.02, 95% CI: 1.57-5.78), single marital status (AOR = 7.72, 95% CI: 3.6-16.53), duration of diabetes mellitus 5 years and more (AOR = 2.00, 95% CI: 1.21-3.5), and having sexual dysfunction (AOR = 3.55, 95% CI: 2.13-5.91) were associated with increased odds of depression among diabetes mellitus patients.

CONCLUSIONS

The prevalence of depression among diabetes mellitus was high. Therefore, the patients should be thoroughly screened for this comorbid condition, and the significant factors should be addressed during routine follow-up.

Health literacy and depression in women with type 2 diabetes mellitus

OBJECTIVES

The prevalence of diabetes mellitus has recently increased in Taiwan, and depression is common among these patients. Moreover, a lack of health literacy may lead to depression. In this study, we explored the correlation between health literacy and depression in diabetic women.

METHODS

In this cross-sectional study, 152 women with type 2 diabetes mellitus were recruited from the outpatient clinic of a regional teaching hospital in Taiwan. The data were collected through medical records and a self-reported structured questionnaire, which included items on basic attributes, self-rated health status, the Center for Epidemiologic Studies Depression Scale (CES-D), and Chinese Health Literacy Scale for Diabetes (CHLSD). The results were analyzed using descriptive statistical analyses, bivariate correlation tests, and linear regression analyses.

RESULTS

One hundred thirty-five valid questionnaires were obtained. Approximately 20% of the participants had a higher tendency toward depression as per their CES-D score, and the CHLSD results showed that 13.33% had poor health literacy. There was a negative correlation between health literacy and depressive tendencies after adjusting for self-rated health status, economic satisfaction status, employment status, and education level using multivariate linear regression analyses. For each 1-point rise in the CHLSD score, the CES-D score decreased by 0.17 points (z=-2.05, p=0.042).

CONCLUSIONS

A negative correlation was identified between health literacy and depression. Self-rated health status, economic satisfaction, employment status, and higher education level are factors that also affect depressive tendency among diabetic women.

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.

Global trends in diabetes complications: a review of current evidence

In recent decades, large increases in diabetes prevalence have been demonstrated in virtually all regions of the world. The increase in the number of people with diabetes or with a longer duration of diabetes is likely to alter the disease profile in many populations around the globe, particularly due to a higher incidence of diabetes-specific complications, such as kidney failure and peripheral arterial disease. The epidemiology of other conditions frequently associated with diabetes, including infections and cardiovascular disease, may also change, with direct effects on quality of life, demands on health services and economic costs. The current understanding of the international burden of and variation in diabetes-related complications is poor. The available data suggest that rates of myocardial infarction, stroke and amputation are decreasing among people with diabetes, in parallel with declining mortality. However, these data predominantly come from studies in only a few high-income countries. Trends in other complications of diabetes, such as end-stage renal disease, retinopathy and cancer, are less well explored. In this review, we synthesise data from population-based studies on trends in diabetes complications, with the objectives of: (1) characterising recent and long-term trends in diabetes-related complications; (2) describing regional variation in the excess risk of complications, where possible; and (3) identifying and prioritising gaps for future surveillance and study.

Prevalence of depression in patients with type 2 diabetes mellitus in Spain (the DIADEMA Study) : results from the MADIABETES cohort

OBJECTIVE

To estimate the prevalence of depression in patients diagnosed with type 2 diabetes mellitus (T2DM), and to identify sociodemographic, clinical and psychological factors associated with depression in this population. Additionally, we examine the annual incidence rate of depression among patients with T2DM.

METHODS

We performed a large prospective cohort study of patients with T2DM from the Madrid Diabetes Study. The first recruitment drive included 3443 patients. The second recruitment drive included 727 new patients. Data have been collected since 2007 (baseline visit) and annually during the follow-up period (since 2008).

RESULTS

Depression was prevalent in 20.03% of patients (n=592; 95% CI 18.6% to 21.5%) and was associated with previous personal history of depression (OR 6.482; 95% CI 5.138 to 8.178), mental health status below mean (OR 1.423; 95% CI 1.452 to 2.577), neuropathy (OR 1.951; 95% CI 1.423 to 2.674), fair or poor self-reported health status (OR 1.509; 95% CI 1.209 to 1.882), treatment with oral antidiabetic agents plus insulin (OR 1.802; 95% CI 1.364 to 2.380), female gender (OR 1.333; 95% CI 1.009 to 1.761) and blood cholesterol level (OR 1.005; 95% CI 1.002 to 1.009). The variables inversely associated with depression were: being in employment (OR 0.595; 95% CI 0.397 to 0.894), low physical activity (OR 0.552; 95% CI 0.408 to 0.746), systolic blood pressure (OR 0.982; 95% CI 0.971 to 0.992) and social support (OR 0.978; 95% CI 0.963 to 0.993). In patients without depression at baseline, the incidence of depression after 1 year of follow-up was 1.20% (95% CI 1.11% to 2.81%).

CONCLUSIONS

Depression is very prevalent among patients with T2DM and is associated with several key diabetes-related outcomes. Our results suggest that previous mental status, self-reported health status, gender and several diabetes-related complications are associated with differences in the degree of depression. These findings should alert practitioners to the importance of detecting depression in patients with T2DM.

Multimorbidity is associated with increased rates of depression in patients hospitalized with diabetes mellitus in the United States

AIMS

Information on the burden and risk factors for diabetes-depression comorbidity in the US is sparse. We used data from the largest all-payer, nationally-representative inpatient database in the US to estimate the prevalence, temporal trends, and risk factors for comorbid depression among adult diabetic inpatients.

METHODS

We conducted a retrospective analysis using the 2002-2014 Nationwide Inpatient Sample databases. Depression and other comorbidities were identified using ICD-9-CM codes. Logistic regression was used to investigate the association between patient characteristics and depression.

RESULTS

The rate of depression among patients with type 2 diabetes increased from 7.6% in 2002 to 15.4% in 2014, while for type 1 diabetes the rate increased from 8.7% in 2002 to 19.6% in 2014. The highest rates of depression were observed among females, non-Hispanic whites, younger patients, and patients with five or more chronic comorbidities.

CONCLUSIONS

The prevalence of comorbid depression among diabetic inpatients in the US is increasing rapidly. Although some portion of this increase could be explained by the rising prevalence of multimorbidity, increased awareness and likelihood of diagnosis of comorbid depression by physicians and better documentation as a result of the increased adoption of electronic health records likely contributed to this trend.

Female sex, young age, northern German residence, hypoglycemia and disabling diabetes complications are associated with depressed mood in the WHO-5 questionnaire - A multicenter DPV study among 17,563 adult patients with type 2 diabetes

BACKGROUND

Like other mental illnesses, depression is a culturally sensitive topic. Hence, findings cannot be transferred between countries. We investigated the frequency of depressed mood and its association with diabetes-related factors in a large type 2 diabetes (T2D) cohort from real-life care in Germany.

METHODS

17,563 adults (median [IQR]: 64.5[55.9-71.1] years) from the multicenter diabetes follow-up registry, DPV (diabetes prospective follow-up), were investigated. All had completed the WHO-5 questionnaire, a screening tool for depression. Logistic regression was applied to study the association of demographic and diabetes-related factors with depressed mood (SAS 9.4). P<0.05 was considered significant.

RESULTS

Using a WHO-5 cut-off of <13, 27.4% of patients were at risk for depressed mood. A clinical depression diagnosis was recognized in 8.4%. Female sex (OR: 1.5[95%-CI: 1.4-1.6]), young age (1.2[1.1-1.4]), longer diabetes duration (1.2[1.1-1.3]), and living in Northern Germany (1.3[1.2-1.4]) were each associated with increased odds for depressed mood. After adjusting for these confounders, worse glycemic control (1.4[1.3-1.5]), insulin use (1.3[1.2-1.4]), myocardial infarction (1.3[1.2-1.5]), stroke (1.8[1.5-2.0]), retinopathy (1.4[1.3-1.6]), renal failure (1.4[1.2-1.8]), diabetic foot syndrome (1.3[1.2-1.4]), severe hypoglycemia (1.5[1.2-1.9]), two or more inpatient admissions (2.1[1.8-2.4]), and longer duration of hospital stay (1-<14 days: 1.3[1.2-2.3]; >14 days: 2.1[1.9-2.3]) were related to depressed mood.

LIMITATION

Due to the cross-sectional design, no causality can be drawn.

CONCLUSIONS

In T2D, depressed mood is not uncommon. However, in routine care a clinical depression might be missed and regular screening is advisable. Besides the well-known associations with depressed mood, northern German residence and mainly life-compromising diabetes comorbidities were identified as related factors.

Comorbidity of depression and diabetes: an application of biopsychosocial model

Background

Type 2 diabetes (T2D) is one of the most psychologically demanding chronic medical illness in adult. Comorbidity between diabetes and depression is quite common, but most studies were based on developed country sample. Limited data exists to document biopsychosocial predictors of depressive symptoms in Ethiopian patients. Therefore, the aim of the study was to describe the association of depressive symptoms and T2D and explore the potential underlying associated biopsychosocial risk factors.

Methods

Institution based cross-sectional study was conducted on 276 patient with T2D at diabetic clinic, Black Lion General Specialized Hospital in Ethiopia. Patients were selected using systematic random sampling technique. Depressive symptoms score, which constructed from a validated nine-item Patient Health Questionnaire (PHQ-9), was an outcome variable. Finally, significant associated factors were identified using multiple linear regression analysis with backward elimination procedure. Statistical Package for Social Science (SPSS) version 22.0 (IBM SPSS Corp.) was used to perform all analysis.

Results

Total of 264 patient data was analyzed with 95.7% response rate. Patients mean (SD) current age and age at diagnosis was 55.9 (10.9) and 43.9 (10.9) years, respectively. Patients waist circumference (mean ± SD) was 98.9 ± 11.1 cm. The average PHQ-9 score was 4.9 (SD 4.1) and fasting blood glucose was 166.4 (SD 73.2). Marital status (divorced), occupation (housewife), diabetic complication (nephropathy), negative life event in the last six months, and poor social support significantly associated with increased mean PHQ-9 score after adjustment for covariates. Whereas not fearing diabetic-related complication and death significantly lower mean PHQ-9 score.

Conclusion

Biopsychosocial variables including marital status, negative life event in the last 6 months, occupation, diabetic complication, and poor social support significantly increase average depressive symptoms score. Evidence-based intervention focusing on these identified biopsychosocial factors are necessary to prevent the development of depressive symptoms.

Electronic supplementary material

The online version of this article (doi:10.1186/s13033-016-0106-2) contains supplementary material, which is available to authorized users.

Comorbidity in Adult Patients Hospitalized with Type 2 Diabetes in Northeast China: An Analysis of Hospital Discharge Data from 2002 to 2013

This study aims to evaluate the comorbidity burden and patterns among adult patients hospitalized with a diagnosis of type 2 diabetes mellitus (T2DM) in Northeast China using hospital discharge data derived from the electronic medical record database between 2002 and 2013. 12.8% of 4,400,892 inpatients aged ≥18 had a diagnosis of T2DM. Sex differences in prevalence varied among those aged <50, 50–59, and ≥60. Twenty-seven diseases were determined as major comorbidities of T2DM. Essential hypertension was the most common comorbidity of T2DM (absolute cooccurrence risk, 58.4%), while T2DM was also the most popular comorbidity of essential hypertension. Peripheral and visceral atherosclerosis showed the strongest association (relative cooccurrence risk, RCoR 4.206). For five leading comorbidities among patients aged ≥40, male patients had a stronger association with disorders of lipid metabolism than female patients (RCoR 2.779 versus 2.099), and female patients had a stronger association with chronic renal failure than male patients (RCoR 2.461 versus 2.155). Leading comorbidities, except chronic renal failure, had declining associations with T2DM with increased age. Collectively, hospital discharge data can be used to estimate disease prevalence and identify comorbidities. The findings provided comprehensive information on comorbidity patterns, helping policy makers and programs in public health domains to estimate and evaluate the epidemic of chronic diseases.

Deconstructing Diabetes and Depression: Clinical Context, Treatment Strategies, and New Directions

Depression and diabetes are common, chronic, and frequently comorbid diseases that contribute substantially to global disability and mortality. Their relationship is bidirectional: depression increases the risk of developing type 2 diabetes mellitus (T2DM), and diabetes increases the risk of depression. Unhealthy lifestyles and poor self-care by patients with depression contribute to the increased T2DM risk. The psychosocial burden of a diabetes diagnosis and its eventual complications predispose diabetic patients to depressive symptoms. Neuroendocrine alterations and inflammation may underlie the increased risk of T2DM in depression but are also proposed as common causative factors for both illnesses. Screening for depression is essential in T2DM, and vice versa. Selective serotonin reuptake inhibitors effectively treat depression of patients with diabetes and positively influence glycemic control. Psychological interventions are effective for depressive symptoms, but their effect on glycemic control varies. Novel depression interventions targeting inflammation or insulin resistance underscore the common biological underpinnings of mood and metabolism.