Identifying the relation between food groups and biological ageing: a data-driven approach.

BACKGROUND: Heterogeneity in ageing rates drives the need for research into lifestyle secrets of successful agers. Biological age, predicted by epigenetic clocks, has been shown to be a more reliable measure of ageing than chronological age. Dietary habits are known to affect the ageing process. However, much remains to be learnt about specific dietary habits that may directly affect the biological process of ageing. OBJECTIVE: To identify food groups that are directly related to biological ageing, using Copula Graphical Models. METHODS: We performed a preregistered analysis of 3,990 postmenopausal women from the Women's Health Initiative, based in North America. Biological age acceleration was calculated by the epigenetic clock PhenoAge using whole-blood DNA methylation. Copula Graphical Modelling, a powerful data-driven exploratory tool, was used to examine relations between food groups and biological ageing whilst adjusting for an extensive amount of confounders. Two food group-age acceleration networks were established: one based on the MyPyramid food grouping system and another based on item-level food group data. RESULTS: Intake of eggs, organ meat, sausages, cheese, legumes, starchy vegetables, added sugar and lunch meat was associated with biological age acceleration, whereas intake of peaches/nectarines/plums, poultry, nuts, discretionary oil and solid fat was associated with decelerated ageing. CONCLUSION: We identified several associations between specific food groups and biological ageing. These findings pave the way for subsequent studies to ascertain causality and magnitude of these relationships, thereby improving the understanding of biological mechanisms underlying the interplay between food groups and biological ageing.

Translation and validation of the Dutch Spine Oncology Study Group Outcomes Questionnaire (SOSGOQ2.0) to evaluate health-related quality of life in patients with symptomatic spinal metastases.

BACKGROUND: The primary goal of palliative treatment of spinal metastases is to maintain or improve health-related quality of life (HRQOL). We translated and validated a Dutch version of The Spine Oncology Study Group Outcome Questionnaire (SOSGOQ2.0), a valid and reliable 20-item questionnaire to evaluate HRQOL in patients with spinal metastases. METHODS: After cross-cultural translation and adaptation, the questionnaire was pre-tested in fifteen patients referred for spine surgery and/or radiotherapy. This resulted in a final questionnaire that was sent to patients for assessment of internal consistency, construct (i.e., convergent and divergent) validity, discriminative power and test-retest reliability. RESULTS: Overall, 147 patients (mean age 65.6 years, SD = 10.4) completed the questionnaire after a median time of 45.4 months (IQR = 18.9-72.9) after spine surgery and/or radiotherapy. Internal consistency was good for the Physical function, Pain, and Mental health domains (α = 0.87, 0.86, 0.72), but not for Social function (α = 0.04). Good convergent validity was demonstrated except for Social function (rs = 0.37 95%CI = 0.21-0.51). Discriminative power between patients with ECOG performance scores of 0-1 and 2-4 was found on all domains and Neurological function items. Test-retest reliability was acceptable for Physical function, Pain and Mental health (ICC = 0.89 95%CI = 0.81-0.94, ICC = 0.88 95%CI = 0.78-0.93, ICC = 0.68 95%CI = 0.48-0.81), whereas ICC = 0.45 (95%CI = 0.17-0.66) for Social function was below threshold. After removing item 20 from the Social function domain, internal consistency improved, and convergent validity and test-retest reliability were good. CONCLUSION: The Dutch version of the SOSGOQ2.0 questionnaire is a reliable and valid tool to measure HRQOL in patients with spinal metastases. Item 20 was removed to retain psychometric properties.

Discovering the direct relations between nutrients and epigenetic ageing.

BACKGROUND: Along with the ageing of society, the absolute prevalence of age-related diseases is expected to rise, leading to a substantial burden on healthcare systems and society. Thus, there is an urgent need to promote healthy ageing. As opposed to chronological age, biological age was introduced to accurately represent the ageing process, as it considers physiological deterioration that is linked to morbidity and mortality risk. Furthermore, biological age responds to various factors, including nutritional factors, which have the potential to mitigate the risk of age-related diseases. As a result, a promising biomarker of biological age known as the epigenetic clock has emerged as a suitable measure to investigate the direct relations between nutritional factors and ageing, thereby identifying potential intervention targets to improve healthy ageing. METHODS: In this study, we analysed data from 3,969 postmenopausal women from the Women's Health Initiative to identify nutrients that are associated with the rate of ageing by using an accurate measure of biological age called the PhenoAge epigenetic clock. We used Copula Graphical Models, a data-driven exploratory analysis tool, to identify direct relationships between nutrient intake and age-acceleration, while correcting for every variable in the dataset. RESULTS: We revealed that increased dietary intakes of coumestrol, beta-carotene and arachidic acid were associated with decelerated epigenetic ageing. In contrast, increased intakes of added sugar, gondoic acid, behenic acid, arachidonic acid, vitamin A and ash were associated with accelerated epigenetic ageing in postmenopausal women. CONCLUSION: Our study discovered direct relations between nutrients and epigenetic ageing, revealing promising areas for follow-up studies to determine the magnitude and causality of our estimated diet-epigenetic relationships.