Are self-reported gastrointestinal symptoms among older adults associated with increased intestinal permeability and psychological distress?

Abstract

Background: Despite the substantial number of older adults suffering from gastrointestinal (GI) symptoms little is known regarding the character of these complaints and whether they are associated with an altered intestinal barrier function and psychological distress. Our aim was to explore the relationship between self-reported gut health, intestinal permeability and psychological distress among older adults.

Methods: Three study populations were included: 1) older adults with GI symptoms (n = 24), 2) a group of older adults representing the general elderly population in Sweden (n = 22) and 3) senior orienteering athletes as a potential model of healthy ageing (n = 27). Questionnaire data on gut-health, psychological distress and level of physical activity were collected. Intestinal permeability was measured by quantifying zonulin in plasma. The level of systemic and local inflammation was monitored by measuring C-reactive protein (CRP), hydrogen peroxide in plasma and calprotectin in stool samples. The relationship between biomarkers and questionnaire data in the different study populations was illustrated using a Principal Component Analysis (PCA).

Results: Older adults with GI symptoms displayed significantly higher levels of both zonulin and psychological distress than both general older adults and senior orienteering athletes. The PCA analysis revealed a separation between senior orienteering athletes and older adults with GI symptoms and showed an association between GI symptoms, psychological distress and zonulin.

Conclusions: Older adults with GI symptoms express increased plasma levels of zonulin, which might reflect an augmented intestinal permeability. In addition, this group suffer from higher psychological distress compared to general older adults and senior orienteering athletes. This relationship was further confirmed by a PCA plot, which illustrated an association between GI symptoms, psychological distress and intestinal permeability.

Keywords: Gastrointestinal symptoms; Intestinal barrier function; Older adults; Psychological distress.

Fig. 1

Intestinal permeability as reflected by plasma zonulin levels in the different groups of older adults. The group of older adults with GI symptoms (n = 22) had significantly higher plasma zonulin levels than and general older adults (n = 21) but not senior orienteering athletes (n = 27). No significant difference was observed between senior orienteering athletes and general older adults. **p < 0.01, *p < 0.05

Fig. 2

Depression and anxiety assessed by HADS in the three different populations of older adults. a) The group experiencing GI symptoms (n = 24) revealed significantly higher depression scores on the HADS scale than the other two groups. A trend towards a significant difference was observed between the senior orienteering athletes (n = 27) and general older adults (n = 22). b) Anxiety score was significantly higher in older adults with GI symptoms compared to the senior orienteering athletes. A significantly lower score was seen in senior orienteering athletes when compared to general older adults, with the latter showing no difference compared to group experiencing GI symptoms. *p < 0.05; **p < 0.01; ***p < 0.001, ns = non-significant

Fig. 3

Principal component analysis displaying the relationship between all investigated biomarkers, HADS domains and GSRS domains in the 3 study populations. Both zonulin and HADS appear associated with the GSRS domains unlike ROS, CRP and calprotectin. The ellipsoid markings cover 95% of the total populations