Depression and Metabolic Syndrome: A Narrative Review.

We reviewed the literature to investigate the relationship between depression and metabolic syndrome. Major depressive disorder is characterized by a low mood or a loss of interest for longer than two weeks. Metabolic syndrome describes multiple metabolic risk factors including obesity, insulin resistance, dyslipidemia, and hypertension. We divided our findings into environmental, genetic, epigenetic, and biological pathway links between depression and the different aspects of metabolic syndrome. We found various sources linking obesity and metabolic syndrome genetically, environmentally, biological pathway-wise, and, while not fully explored, epigenetically. Diabetes and depression were also found to be linked environmentally with both conditions increasing the risk of the other. Depression was also shown to be linked to cardiovascular complications as it increased the risk of occurrence of such complications in healthy people. These findings have led us to believe that there is a link between depression and metabolic syndrome on various levels, especially obesity.