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Diabetes Y Depresión 50 Artículo Original Diabetes y depresión José Francisco Caro, Juan Rosas Guzmán Abstract algum grau de depressão, o que favorece um mau controle metabólico. Por outro lado, o diabetes compli- The relationship between diabetes mellitus and depres- cado com manifestações tardias agrava a depressão. sion is not always recognized. About one third of the A depressão pode aumentar até 37% o risco para patients with diabetes have some degree of depres- desenvolver diabetes mellitus tipo 2 quando se com- sion, which favours a poor metabolic control. On the para com quem não tem um estado depressivo. Embora other hand, late complications of diabetes further quando não há um fator etiopatológico identificável, aggravate depression. câmbios em diferentes sistemas hormonais (cortisol, Depression can increase up to 37% the risk for devel- insulina, hormônio de crescimento, etc.) neurotrans- oping type 2 diabetes mellitus when compared to missores (serotonina) e o sistema nervoso autônomo non-depressed subjects. Even when there is not an ativado jogam um papel relevante. identifiable etiopathologic factor, changes in different O tratamento deve-se realizar tal como corresponde a hormonal systems (cortisol, insulin, growth hormone, cada uma das entidades para conseguir o bem-estar etc.), neurotransmitters (serotonin), and the activated pleno da pessoa. autonomous nervous system play a relevant role. Treatment must be adjusted according to guidelines Introducción established for each entity present to achieve complete well-being of the person. In the past few years, it has been recognized an inter- action between diabetes mellitus and depression. Resumen Even being two separate entities, they have an intimate relationship over their natural history. Prevalence studies La relación entre diabetes mellitus y depresión no siem- have shown that depression favours the development of pre es reconocida. Se sabe que aproximadamente una diabetes mellitus, and that a high percentage of people tercera parte de los pacientes con diabetes tienen with diabetes usually suffer from depression as well. algún grado de depresión, lo que favorece un mal con- That is why we have decided to make an analysis of trol metabólico. Por otro lado, la diabetes complicada the existing evidence that relate diabetes mellitus and con manifestaciones tardías agrava la depresión. depression, answering the following questions: La depresión puede incrementar hasta un 37% el ries- go para desarrollar diabetes mellitus tipo 2 cuando se 1) Is there an association between diabetes compara con quien no tiene un estado depresivo. Aún and depression? cuando no hay un factor etiopatológico identificable, cambios en diferentes sistemas hormonales (cortisol, In the United States, about 7% of the population, or 20 insulina, hormona de crecimiento, etc), neurotrans- million people, have diabetes. Depression affects 10% misores (serotonina) y el sistema nervioso autónomo of the adult population, and women have a twofold activado juegan un papel relevante. higher prevalence of depression than men. One-third of El tratamiento deberá realizarse tal como corresponde people having diabetes are undiagnosed and therefore a cada una de las entidades para lograr el bienestar untreated. This is also a problem in depression. pleno de la persona. In a meta-analysis of 42 published studies including 21,351 adults, the prevalence of major depression in Resumo people having diabetes was 11 % and the prevalence of clinically relevant depression was 31%.1 A relação entre diabetes mellitus e depressão não Overall, studies have shown that individuals with sempre é reconhecida. Sabe-se que aproximadamente depression are more than twice as likely to have dia- uma terceira parte dos pacientes com diabetes têm betes as individuals without depression. Furthermore, Trabajo recibido el 7/1/2008 y aceptado el 15/1/08 Dirección Postal: Dr. Juan Rosas Guzman. Jefe Unidad de Investigación Centro de Especialidades Médicas de Celay – Mexico. E-mail: [email protected] VOL. XVI - Nº 2 - Año 2008 José Francisco Caro, Juan Rosas Guzmán 51 there are indications that depressive states are more magnitude to the combined risk of smoking and lack common in diabetes than in other diseases with com- of exercise. parable physical and psychological suffering.2 The metabolic syndrome and obesity are both risk Although this is the first and simplest question of this factors for the development of diabetes. In a longitu- paper, its answer is not conclusive. The definitions dinal study women with a history of major depressive and methods of diagnosis for both depression and episodes were twice as likely to have the metabolic diabetes are different among studies. There is a pau- syndrome compared with those having no history of city of well-conducted and well-powered prospective depression.9,10 The relationship between depression and rigorously designed studies as was recognized and the metabolic syndrome remained after control- in November of 2002 by The Depression and Bipolar ling for age, race, education, smoking, physical inac- Support Alliance.3 Five years later, the continued lack tivity, carbohydrate consumption and alcohol use. of data and clear awareness of the problem of diabetes Interestingly, men with a history of depression were and depression in the medical and scientific communi- not significantly more likely to develop the metabolic ties is one of the reasons for this work. syndrome.9 The association between obesity and depression is well 2) How serious is the co-morbidity of diabetes recognized.10 However, most studies do not show con- and depression? clusively whether obesity leads to depression or vice versa. It is almost certain that the association works in The burden of co-morbid depression on patients with both directions. However, data from three longitudinal diabetes is profound. There is strong evidence that the studies including more than 10000 subjects indicate coexistence of diabetes and depression is associated that depression in childhood and adolescence may with poor diabetes outcomes. The impact of diabetes lead to adolescence or adult obesity.11 Furthermore, on depression outcomes has received little attention. the National Longitudinal Alcohol Epidemiology Survey In a large meta-analysis that included individual who had found that, among subjects age 18 or older, a BMI of 30 type 1 or type 2 diabetes, depression was associated or greater was positively associated with past depres- significantly with poor control.4 Patients having diabe- sion only in women.12 tes with co morbid depression suffer increased mor- Thus, it appears that depression is a predictor of obes- bidity, mortality, and health care costs, and decreased ity, the metabolic syndrome, and diabetes. However, work productivity and quality of life.5 Unsurprisingly, recognizing the heterogeneity of these conditions, it is much of this morbidity and mortality is related to car- possible that those processes can be bidirectional. diovascular disease. Adoption of appropriate self-care behaviors (regular exercise, dietary intake, home blood 4) Is there a mechanistic link between diabe- glucose monitoring, etc) is an integral part of good dia- tes and depression? betes care, yet very difficult for the depressed person with diabetes to do.5 Depression, obesity, the metabolic syndrome, diabe- We are not aware of any consensus conference or tes, and macrovascular disease are called “complex position statement by the ADA alone or in cooperation diseases”. They are polygenic diseases in which with any of the psychiatric associations focusing on the susceptibility genes are in constant interaction with problem of diabetes and depression. the environment, resulting in expression of a given phenotype. Thus, it is very unlikely that any mecha- 3) What is the temporal relationship between nistic links among these diseases would be simple diabetes and depression? and obvious. An established neuro-endocrine abnormality in Depression is often regarded as a co-morbid condition depression is the hyperactivity of the hypothalamic- that results from the daily burden of having diabetes pituitary-adrenal (HPA) axis. Increased cortisol pro- and its complication. However, it appears that the real- duction in depression may result in insulin resistance, ity is different. decreased insulin secretion, and central obesity, which A meta-analysis of nine longitudinal studies suggest- are premonitory of the metabolic syndrome and dia- ed that adults with depression have a 37% increase betes. Diminished sex steroids and growth hormone in risk of developing type 2 diabetes compared with in depression have metabolic consequences similar those who are not depressed.6 In some of these those of hypercortisolism. Elevated activity of the sym- studies, the risk persisted even after adjusting for pathetic nervous system in depression would result body weight, BMI, physical activity, family history of in elevated blood pressure and also abnormalities in diabetes, socioeconomic status, and education7 and insulin action and secretion. The decreased tone of the is stronger in females.8 Thus, depression appears to central serotonin system in depression may increase by be an independent risk factor for diabetes similar in a high carbohydrate diet and could facilitate the devel- 52 Diabetes y depresión opment of obesity and the metabolic syndrome. Finally, ing. Accumulation of adipose tissue is the critical the pro-inflammatory state that leads to atherosclero- signal for the initiation
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