The 'cerebral diabetes' paradigm for unipolar depression

Depression is to diabetes as antidepressants are to insulin: the unraveling of an analogy?

The common comparison of depression to diabetes enables the construction of depression as a nonstigmatizing chronic illness that requires medication. We explore, through the use of discourse analysis, how both long-term users of antidepressants and family physicians invoked this analogy in research interviews. Specifically, we show how these participants explicitly or implicitly challenged the aptness of the depression-diabetes analogy as framed either within a generic (and presumably type 1) conception of diabetes or within the model of type 2 diabetes. These challenges include demonstrating how the elements or inferences of the analogy do not correspond, and how the analogy does not have its intended effects. We consider the implications of the unraveling of this analogy for the construction of depression as a chronic medical condition, for the supposed ease of prescribing and taking antidepressants, and for the reduction of stigma.

Behavioral genetics of the depression/cancer correlation: a look at the Ras oncogene family and the 'cerebral diabetes paradigm'

This study investigates the causes of the observed linkage between depression and later onset of cancer. The prevailing view is that cancer in depressed patients results from a weakened immune system. However, molecular biologists have recognized that dysregulation of the ras proto-oncogene results in impaired serotonin and dopamine synthesis manifesting as major depression. A qualitative review of the literature showed that (1) studies using the Minnesota Multiphasic Personality Inventory showed a greater correlation between depression and later cancer onset than those employing other measures and (2) the more related the cancer type was to the Ras oncogene family, the greater the correlation between depression and later cancer onset. These results support the hypothesis that the ras proto-oncogene plays a role in the etiology of depression and could be the common denominator in long-observed depression/cancer linkages. Previous depression/cancer linkage studies are confounded in that they failed to analyze cancer type and accurately diagnose depression.

Intractable vomiting in diabetic patients

Intractable nausea and vomiting have been described in individuals without any underlying physical etiology explaining these complaints. Physical or emotional abuse has been described in individuals suffering from these symptoms and associated with somatoform disorders manifesting primarily as gastrointestinal complaints. We present five patients with long-standing Type 1 diabetes who suffered from intractable vomiting. Personality disorders, profound depression and emotional abuse dramatically influenced the course of these patients' illness. In most of the patients, physical symptoms remarkably improved after identification and removal of the triggering factors. Therefore, psychogenic vomiting must be considered among the differential diagnoses of intractable nausea and vomiting, especially in individuals with chronic illnesses. A careful search for a physical etiology and medical treatment that does not cause relief of symptoms should suggest that there is almost certainly a psychological issue at the root of the problem.

Insulin resistance: a metabolic link between depressive disorder and atherosclerotic vascular diseases

The association of depression with insulin resistance (IR) and athersclerotic vascular diseases has been well documented. This review examines the relevance of IR as a link between depressive disorder and atherosclerotic vascular diseases. Relevant articles collected from Medline database over the period of 1966-2001 were reviewed. Studies have shown that IR is a state-dependent abnormality in depression and depression increases the risk of vascular morbidity and mortality. Given that IR is a central component of cardiovascular risk factors, depression-related IR might play a role in the development and progression of coronary and cerebral atherosclerosis in chronic-resistant depression. Further, IR may contribute to the pathophysiology of depressive disorder. In conclusion IR could account for the linkage between depression and atherosclerotic vascular diseases. More studies are needed to examine the importance of improving insulin sensitivity in the treatment of chronic-resistant depression and prevention of depression-related vascular morbidity and mortality.

Schizophrenia is a diabetic brain state: an elucidation of impaired neurometabolism

In this paper a detailed argument will be advanced in support of the notion that schizophrenia is fundamentally a diabetic brain state, henceforth referred to as 'cerebral diabetes'. Many extraneous features of cerebral diabetes have been observed, including positron emission tomography (PET) scans which reflect abnormal distribution patterns and diminished supplies of glucose in the brain. Equally, empirical research has demonstrated that plasma levels of essential fatty acids and prostaglandins are abnormally low, and low levels of glycoproteins in the urine of cerebral diabetics have also been observed. In addition, cerebral diabetics manifest a wide range of disturbing physical symptoms, such as, impaired sexual function, temperature control, low blood pressure, disrupted sleep patterns, excessive thirst, poor memory, insensitivity to pain, and chronic unhappiness, all of which can be attributed to disrupted neuroendocrine function. Thus, in order to persuasively assert the redefinition of schizophrenia as 'cerebral diabetes', we shall first explicate glucose regulation and transport in the brain and then outline how this interacts with essential fatty acids and prostaglandins, neurotransmission, and the neuroendocrine system. In so doing, we shall provide a metabolic explanation for all the prominent symptoms currently known to be associated with cerebral diabetes and indicate some future therapeutic interventions.

Schizophrenia: an extended etiological explanation

Schizophrenia has become an elusive medical conundrum since it was first described at the turn of the 19th century. Over time, a variety of causal hypotheses have been advanced to explain the spectrum of schizophreniform disorders. This etiological explanation outlines the relationship that obtains between smoking, schizophrenia, and impaired glycometabolism which also includes disruption to the dopaminergic and serotinergic pathways. A possible genetic explanation for this disruption will be identified which links mental illness to a locus of genes contained on the short arm of chromosome 11. These genes are all essential to normal glucose transport which positron emission tomography (PET) scans show is seriously abnormal in schizophrenia. Thus, a redefinition of schizophrenia as 'cerebral diabetes' will be proposed since this term implies a diabetic brain state consistent with PET scans of schizophrenic patients.