The Trinity, Ulster and Department of Agriculture Cohort Study (TUDA)

Background:

Cardiovascular disease (CVD), osteoporosis and dementia are chronic diseases of ageing that impact adversely on the lives of those affected and have major health, social and economic consequences. A number of factors are considered to be implicated in these diseases, ranging from the more established factors to those that are less well recognised. Lifestyle factors such as diet, body weight, smoking, physical activity and years of education are acknowledged as risk factors for the development of these chronic diseases of aging. Emerging research suggests that elevated homocysteine and/or sub-optimal status of the metabolically related B-vitamins (folate, vitamin B12, B6 and riboflavin) may be associated with a higher risk of age-related disease. The interplay between relevant genetic and nutrient factors (gene-nutrient interactions) is considered to be highly relevant in the development (and prevention) of chronic diseases of ageing, however this relatively new area of research is as yet poorly understood. The collection of clinical, lifestyle, nutritional and genetic data on large numbers of patients would permit the investigation of those nutrients which interact with specific genes to increase the likelihood of a person developing chronic diseases of ageing.

Aim:

The aim of the TUDA study is to collect detailed clinical, lifestyle, dietary, genetic and biochemical data to investigate gene-nutrient interactions (particularly from the perspective of the B-vitamins and vitamin D/calcium) in the development of CVD, osteoporosis and dementia by studying older adults exhibiting the early stages of these common diseases, namely hypertension, low bone mineral density, and early memory loss, respectively.

Secondary aim (follow up TUDA investigation):

The aim of this longitudinal investigation is to re-assess clinical, nutritional, genetic and biochemical factors in relation to the progression of disease outcomes in TUDA study participants, in subsequent years after initial investigation.

Study design:

A total of 6000 non-institutionalised older Irish people aged over 60 years with early predictors of either dementia, stroke and osteoporosis (namely early memory loss, high blood pressure and low bone mineral density, respectively) recruited from three centres (St James's Hospital Dublin, Ulster University Coleraine and The Clinical Translational Research and Innovation Centre (C-TRIC), Londonderry) across Ireland. Non-fasting blood samples were collected from all subjects and routine blood biochemistry profiles and biomarkers of relevance to B vitamin and vitamin D status were measured. Supplement use was recorded and a targeted food frequency questionnaire was used to record dietary intakes of specific vitamins of interest (folate, B12, B6, riboflavin and D) from major food sources, particularly fortified foods. Physiological function tests including blood pressure, bone health (DXA scans) and cognitive function tests and anthropometric measures were also taken.