Relationship(s) between obesity and inflammatory bowel diseases: possible intertwined pathogenic mechanisms

Abstract

The inflammatory bowel diseases, Crohn's and ulcerative colitis have increased in incidence and prevalence from the mideighteen to the late nineteen centuries. From then to the current twenty-first century there has been a more rapid expansion of these disease to areas previously experiencing low rates. This latter expansion coincides with the current obesity pandemic which also began toward the end of the last century. Although the two diseases have radically different frequencies, there are interesting links between them. Four areas link the diseases. On an epidemiological level, IBD tends to follow a northsouth gradient raising the importance of vitamin D in protection. Obesity has very weak relationship with latitude, but both diseases follow adult lactase distributions colliding in this plane. Is it possible that obesity (a low vitamin D condition with questionable response to supplements) reduces effects in IBD? On a pathogenic level, pro-inflammatory processes mark both IBD and obesity. The similarity raises the question of whether obesity could facilitate the development of IBD. Features of the metabolic syndrome occur in both, with or without obesity in IBD. The fourth interaction between the two diseases is the apparent effect of obesity on the course of IBD. There are suggestions that obesity may reduce the efficacy of biologic agents. Yet there is some suggestion also that obesity may reduce the need for hospitalization and surgery. The apparent co-expansion of both obesity and IBD suggests similar environmental changes may be involved in the promotion of both.

What Was First, Obesity or Inflammatory Bowel Disease? What Does the Gut Microbiota Have to Do with It?

“…Moreover, obesity has been shown to have an adverse effect on biological therapy. The literature mainly presents such connections for infliximab and adalimumab [ 56 ]. Due to increased body weight, there is a faster optimization of the patients’ infliximab levels and therefore a higher dose regimen may be necessary [ 57 ].…”

“…In addition, bacterial lipopolysaccharide (LPS) may trigger a signal to induce low-grade inflammation that contributes to diabetes, obesity and the metabolic syndrome [ 83 ]. In both IBD and obesity, there is an increase in Proteobacteria, Ruminococcus gnavus and a decrease in Clostridium (leptum) and Faecalibacterium prausnitzii [ 56 ].…”

Characterization of the serum levels of Meteorin-like in patients with inflammatory bowel disease and its association with inflammatory cytokines

“…Recent epidemiological studies have also shown that incidence of IBD is rising in parallel with obesity prevalence [ 4 , 5 ]. Moreover, the rate of hospitalization and surgery are more frequent among IBD patients with obesity [ 6 ]. Scientific studies have suggested that, genetics, gut microbiome, and the immune system may play critical roles in IBD, however, this has not completely understood yet [ 7 ].…”

Characterization of the Serum Levels of Meteorin-like in Patients with Inflammatory Bowel Disease and its Association with Inflammatory Cytokines

“…Recent epidemiological studies have also shown that increasing rate of IBD is parallel with the obesity prevalence [4,5]. Moreover, hospitalization and surgery are more frequent among IBD patients with obesity [6]. Although it is not fully understood yet, scienti c studies have suggested that, genetics, gut microbiome, and the immune system may play critical roles in IBD [7].…”