Depression in neurodegenerative diseases: Common mechanisms and current treatment options.

Major depressive disorder (MDD) is a highly prevalent psychiatric disorder and a major cause of disability worldwide. This neurological condition is commonly associated with neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's disease (PD) and Huntington's disease (HD), and has a significant impact on the increasing burden of these neuropathologies. Over the past decades, some of the pathophysiological and molecular mechanisms that contribute to these diseases have been elucidated and these findings indicate that, despite presenting distinct features, there are several similarities between the neurobiological alterations that lead to MDD and neurodegeneration in AD, PD, and HD. For instance, disturbances in monoaminergic transmission and the hypothalamic-pituitary-adrenal (HPA) axis, increased oxidative and neuroinflammatory events, and impaired trophic support are thought to contribute to neuronal atrophy and death in all these diseases. In addition, neuroimaging findings have helped elucidate the structural and functional changes implicated in the relationship between depression and neurodegeneration, thus establishing a neuroanatomical signature to explain, at least in part, the comorbidity between MDD and AD, PD, and HD. The present review summarizes these findings and the current evidence regarding the effectiveness of common antidepressant therapies for the treatment of MDD in patients with these neurodegenerative diseases. This population is particularly vulnerable to the drawdowns of conventional antidepressant therapy (namely inadequate response and high risk of side effects), and the development of emerging therapeutic approaches to treat MDD in patients with AD, PD, and HD is thus of paramount importance to improve the quality of life of these individuals.

Annual Incidence and Phenotypic Presentation of IBD in Southern New Zealand: An 18-Year Epidemiological Analysis.

BACKGROUND: The aim of this study was to describe the incidence of inflammatory bowel disease (IBD) and changes in demographic and phenotypic disease presentation in Otago, New Zealand. METHODS: This study was conducted at Dunedin Hospital and the study period was 1996-2013. Otago residents diagnosed with IBD were identified retrospectively from hospital lists using ICD-10 codes. Diagnosis, and place and date of diagnosis, were confirmed using medical notes and histology reports. Demographic, clinical and diagnostic data were recorded. Age-standardised incidence rates were estimated and trends over time assessed. Multinomial logistic regression was used to assess evidence for any changes in the distribution of disease location for Crohn's disease (CD) cases. RESULTS: The diagnosis of IBD was confirmed in 224 males and 218 females, and most were New Zealand European. Of the total number of confirmed IBD cases, 40.0% were ulcerative colitis (UC), 52.1% were CD and 7.9% were IBD unclassified. The age distribution illustrated bimodal peaks at 20-24 years and 65-69 years. Incidence rates varied from year to year, but there was no statistically significant change over the 18-year study period. The estimated age-standardised IBD incidence varied between 5.8/100,000 in 2006 and 29.8/100,000 in 2012. The incidence rates for UC and CD were 2.8/100,000 and 1.8/100,000, respectively, in 2006 and 6.3/100,000 and 21.8/100,000, respectively, in 2012. There were no significant phenotypic changes in CD patients over the study period. CONCLUSIONS: The IBD incidence in Otago, New Zealand, is high compared to many other countries. Annual age-standardised incidence rates vary, highlighting the limitations of single-year incidence data.