Guest, M. Aaron

An emerging area of research extends work on couple functioning and physical health to gut health, a critical marker of general health and known to diminish with age. As a foray into this area, we conducted a pilot study to (1) determine the feasibility of remote data collection, including a fecal sample, from older adult couples, (2) examine within-couple concordance in gut microbiota composition, and (3) examine associations between relationship functioning and gut microbiota composition. Couples (N = 30) were recruited from the community. The participants’ demographic characteristics were as follows: M (SD) age = 66.6 (4.8), 53% female, 92% White, and 2% Hispanic. Two of the couples were same-sex. All 60 participants completed self-report measures and supplied a fecal sample for microbiome analysis. Microbial DNA was extracted from the samples, and the 16S rRNA gene V4 region was amplified and sequenced. The results indicated that individuals shared more similar gut microbial composition with their partners than with others in the sample, p < 0.0001. In addition, individuals with better relationship quality (greater relationship satisfaction and intimacy and less avoidant communication) had greater microbial diversity, p < 0.05, a sign of healthier gut microbiota. Further research with a larger and more diverse sample is warranted to elucidate mechanisms.

Abstract An emerging area of research extends work on couple functioning and physical health to gut health, a critical marker of general health and known to diminish with age. As a foray into this area, we conducted a pilot study to determine feasibility of data collection (questionnaires and a stool sample) among older adult couples. Participants were recruited from the community using a variety of methods including social media. Among 41 persons responding with interest across recruitment sources, 32 were contacted for screening. Inclusion criteria were: age 60+, marriage or cohabiting partnership, and English speaking/understanding. Exclusion criteria were a gastrointestinal disorder, receiving enteric nutrition, use of antibiotics (past month), cancer treatment (past 6 months), and a +COVID-19 diagnosis (past 2 months). Among 31 eligible couples, 30 consented. All 60 participants completed questionnaires and provided a stool sample using DNAgenotek’s OMR-200 collection kit, chosen for its ease and because samples can be stored at room temperature for 60 days. Sample characteristics were: M (SD) age = 66.57 (4.78); 53.3% female; 91.7% White; 1.7% Latinx; and 78.3% college-educated. 2 couples were same-sex. 43% reported at least one health condition and 25% reported use of a proton pump inhibitor (which can affect the gut microbiome), though none daily. Relational well-being was moderate-high on average per measures of dyadic adjustment and intimacy. Despite original plans to recruit couples in-person from a retirement community, remote operations were feasible via online assessment and study-coordinated shipping, a necessary yet fruitful shift due to the SARS-CoV-2 pandemic.