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Reduced balance function has been observed during balance challenging conditions in the chronic obstructive pulmonary disease (COPD) population and is associated with an increased risk of falls. This study aimed to examine postural balance during quiet standing with eyes open and functional balance in a heterogeneous group of COPD and non-COPD (control) subjects, and to identify risk factors underlying balance impairment using a large panel of methods. In COPD and control subjects, who were mostly overweight and sedentary, postural and functional balance were assessed using center-of-pressure displacement in anterior-posterior (AP) and medio-lateral (ML) directions, and the Berg Balance Scale (BBS), respectively. COPD showed 23% greater AP sway velocity (p = 0.049). The presence of oxygen therapy, fat mass, reduced neurocognitive function, and the presence of (pre)diabetes explained 71% of the variation in postural balance in COPD. Transcutaneous oxygen saturation, a history of exacerbation, and gait speed explained 83% of the variation in functional balance in COPD. Neurocognitive dysfunction was the main risk factor for postural balance impairment in the control group. This suggests that specific phenotypes of COPD patients can be identified based on their type of balance impairment.

Background Small‐ and large‐intestinal perturbations have been described as prevalent extracardiac systemic manifestations in congestive heart failure (CHF), but alterations in protein digestion and absorption and plasma short‐chain fatty acid (SCFA) concentrations and the potential link with other systemic effects (muscle and cognitive health) have not been investigated in CHF. Methods We analyzed protein digestion and absorption with dual stable tracer method in 14 clinically stable, noncachectic CHF outpatients (mean left ventricular ejection fraction: 35.5% [95% CI, 30.9%–40.1%]) and 15 controls. Small‐intestinal non–carrier‐mediated permeability and active carrier‐mediated glucose transport were quantified by sugar permeability test. Plasma SCFA (acetate, propionate, butyrate, isovalerate, valerate) concentrations were measured as intestinal microbial metabolites. Muscle function was assessed by isokinetic dynamometry, cognition by a battery of tests, and well‐being by questionnaire. Results Protein digestion and absorption were impaired by 29.2% (P = .001) and active glucose transport by 38.4% (P = .010) in CHF. Non–carrier‐mediated permeability was not altered. Whereas plasma propionate, butyrate, and isovalerate concentrations were lower in CHF (P < .05), acetate and valerate concentrations did not differ. Overall, intestinal dysfunction was associated with impaired leg muscle quality, emotional distress, and cognitive dysfunction (P < .05). Conclusions We identified impaired protein digestion and absorption and altered SCFA concentrations as additional intestinal dysfunctions in CHF that are linked to reduced muscle and cognitive health and well‐being. More research is needed to implement strategies to improve intestinal function in CHF and to investigate the mechanisms underlying its link with other systemic manifestations.

The short-chain fatty acids (SCFAs) acetate, propionate, butyrate, isovalerate, and valerate are end products of intestinal bacterial fermentation and important mediators in the interplay between the intestine and peripheral organs. To unravel the transorgan fluxes and mass balance comparisons of SCFAs, we measured their net fluxes across several organs in a translational pig model. In multi-catheterized conscious pigs (n=12, 25.6 (95% CI [24.2, 26.9]) kg, 8-12 weeks old), SCFA fluxes across portal drained viscera (PDV), liver, kidneys, and hindquarter (muscle compartment) were measured after an overnight fast and in the postprandial state, 4 h after administration of a fiber-free, mixed meal. PDV was the main releasing compartment of acetate, propionate, butyrate, isovalerate, and valerate during fasting and in the postprandial state (all P=0.001). Splanchnic acetate release was high due to the absence of hepatic clearance. All other SCFAs were extensively taken up by the liver (all P<0.05). Even though only 7% [4, 10] (propionate), 42% [23, 60] (butyrate), 26% [12, 39] (isovalerate), and 3% [0.4, 5] (valerate) of PDV release were excreted from the splanchnic area in the fasted state, splanchnic release of all SCFAs was significant (all P≤0.01). Splanchnic propionate, butyrate, isovalerate and valerate release remained low but significant in the postprandial state (all P<0.01). We identified muscle and kidneys as main peripheral SCFA metabolizing organs, taking up the majority of all splanchnically released SCFAs in the fasted state and in the postprandial state. We conclude that the PDV is the main SCFA releasing and the liver the main SCFA metabolizing organ. Splanchnically released SCFAs appear to be important energy substrates to peripheral organs not only in the fasted but also in the postprandial state.

Purpose of review This review will discuss recent studies showing that patients with chronic wasting diseases suffer from a variety of small intestinal impairments which might negatively impact the colonic microbiota and overall well-being. New insights will be addressed as well as novel approaches to assess intestinal function. Recent findings Small intestinal dysfunction can enhance the amount and alter the composition of undigested food reaching the colon. As a result of reduced protein digestion and absorption, a large amount of undigested protein might reach the colon promoting the presence of pathogenic colonic bacteria and a switch from bacterial fiber fermentation to protein fermentation. While microbial metabolites of fiber fermentation, such as short-chain fatty acids (SCFA), are mainly considered beneficial for overall health, metabolites of protein fermentation, i.e. ammonia, branched SCFAs, hydrogen sulfide, polyamines, phenols, and indoles, can exert beneficial or deleterious effects on overall health. Substantial advances have been made in the assessment of small intestinal dysfunction in chronic diseases, but studies investigating the connection to colonic microbial metabolism are needed. A promising new stable isotope approach can enable the measurement of metabolite production by the colonic microbiota. Summary Several studies have been conducted to assess intestinal function in chronic diseases. Impairments in intestinal barrier function, sugar absorption, protein digestion, and absorption, as well as small intestinal bacterial overgrowth were observed and possibly might negatively impact colonic bacterial metabolism. We suggest that improving these perturbations will improve overall patient health.