Cognitive Therapy Looks Beyond Childhood to Help Depressed Patients
Suzanne Leigh of San Franciso Chronicle wrote an excellent article about cognitive therapy as a depression treatment modality.
“Don’t Tell Me About Your Childhood” began with the general idea of talk therapy we’ve come to know. Whenever we think about psychotherapy, we’d have an image of a patient on a couch speaking with a somewhat disinterested therapist who would be asking the patient about his or her mother or childhood. Read more
Depression and Bipolar Disorder Gene Not Linked to Serotonin
Many antidepressants work by changing serotonin levels in the brain, which is why these classes of antidepressants are called Selective Serotonin Receptor Inhibitors (SSRIs). In May 2006, a study was published in the American Journal of Medical Genetics that suggests that a gene for major depressive disorders (including bipolar disorder) was found, and is not linked to serotonin. ScientistLive.com published a commentary about this study.
This gene is called P2RX7 and is found in humans and animals. This marked an advance in understanding the genetic basis of depressive disorders. Professor Barden was a lead investigator in the study and was quoted to say, “What is particularly exciting is that P2RX7 has nothing to do with serotonin.” Barden speculated that future antidepressants may directly target the P2RX7 gene, and current antidepressants may take weeks to have an effect because current antidepressants bypass P2RX7. In animal studies. directly targeting P2RX7 was shown to have an antidepressive effect.
Barden concluded that how P2RX7 works is still unknown, and may be part of a larger genetic network that is responsible for depression.
I’m including the Original Abstract for those of you curious about the scientific jargon:
Barden N, Harvey M, Gagné B, Shink E, Tremblay M, Raymond C, Labbé M, Villeneuve A, Rochette D, Bordeleau L, Stadler H, Holsboer F, Müller-Myhsok B. 2006. “Analysis of Single Nucleotide Polymorphisms in Genes in the Chromosome 12Q24.31 Region Points to P2RX7 as a Susceptibility Gene to Bipolar Affective Disorder.” Am J Med Genet Part B 141B:374-382.
Abstract
Previous results from our genetic analyses using pedigrees from a French Canadian population suggested that the interval delimited by markers on chromosome 12, D12S86 and D12S378, was the most probable genomic region to contain a susceptibility gene for affective disorders. Association studies with microsatellite markers using a case/control sample from the same population (n = 427) revealed significant allelic associations between the bipolar phenotype and marker NBG6. Since this marker is located in intron 9 of the P2RX7 gene, we analyzed the surrounding genomic region for the presence of polymorphisms in regulatory, coding and intron/exon junction sequences. Twenty four (24) SNPs were genotyped in a case/control sample and 12 SNPs in all pedigrees used for linkage analysis. Allelic, genotypic or family-based association studies suggest the presence of two susceptibility loci, the P2RX7 and CaMKK2 genes. The strongest association was observed in bipolar families at the non-synonymous SNP P2RX7-E13A (rs2230912, P-value = 0.000708), which results from an over-transmission of the mutant G-allele to affected offspring. This Gln460Arg polymorphism occurs at an amino acid that is conserved between humans and rodents and is located in the C-terminal domain of the P2X7 receptor, known to be essential for normal P2RX7 function. © 2006 Wiley-Liss, Inc.
Like Some Antipsychotic Meds, Antidepressants May Increase Diabetes Risk
For most depressed patients, taking antidepressants are a risk-benefit ratio; improving depression comes with a set of side effects that require management in the long term. For a population of depressed patients who may be at risk for developing type 2 diabetes, antidepressants have been a cause for concern because of an association between antidepressants and development of type 2 diabetes.
American Diabetes Association (ADA) announced that antidepressants may increase the risk of type 2 diabetes for depressed patients who already have that risk. This came from ADA’s 2006 scientific meeting held during the summer. The association also published on the role of depression and developing diabetes, which you may access via this PDF from ADA’s website. Those with depression and diabetes definitely need to carefully manage both conditions.
In one of the studies looking at antidepressants and diabetes, people with high diabetes risk who took antidepressants were 2 to 3 times more likely to develop diabetes during the course of the study, compared with people who did not take antidepressants. This study is important because there had been headlines for some time about antipsychotic medications increasing diabetes risk, but this is the first time that antidepressant drugs have been linked to increasing diabetes risk. How this happens (the mechanism) is still unclear at this time.
Debate also centered already a “chicken or egg” question: which came first, the diabetes or depression? Certainly, people with chronic conditions (chronic pain, cardiovascular conditions, diabetes) are understandably prone to triggers causing depression. What is not yet known is whether depression is caused by the diabetic condition, although most endocrinologists realize that depression can occur in diabetic patients.
Search for more: ADA’s Press Release or Google News on Antidepressants and Diabetes