Funds have already been obtained to complete 3500 ultrasound scans of the liver to obtain parameters for non-alcoholic fatty liver disease (NALFD) at the 17+ clinic and also to complete assays for biomarkers for NAFLD, including ALT, AST, GGT, total bilirubin, fasting glucose, total cholesterol, HDLc, LDLc, triglycerides, apolipoprotein A1 (ApoA1), fasting insulin, alpha 2 macroglobin and haptoglobin, on bloods taken at both the 15+ (N=3500) and the 17+ clinics (N=3500) [DA Lawlor PI MRC grant]. Funds to do conventional and tissue Doppler echocardiography (and obtain detailed measures of cardiac structure and function) [GRACE; BHF funded PI A Hughes], to measure carotid IMT, heart rate variability [BHF grant PI J Deanfield], & central and 24-hour blood pressure [ELBA; Wellcome Trust PI A Hughes] in the 17+ clinic have also been secured. In previous proposals we (DA Lawlor & A Fraser) requested and were given permission to examine early life determinants of NAFLD and the relationship between NAFLD and insulin resistance (objectives 1 and 2 below). Here we request permission to complete additional analyses concerned with the association of NAFLD with vascular outcomes in ALSPAC (objectives 3 & 4 below). We intend to submit a project grant to the BHF to fund a statistician/epidemiologist to complete all of the objectives listed below.

In adults there is increasing evidence linking NAFLD to increased cardiovascular morbidity (CVD) and mortality but the nature of this association, i.e. whether common causes such as obesity, physical inactivity and insulin resistance explain this association or whether NAFLD is a risk factor for CVD above and beyond other risk factors remains unclear (Targher, Diabetologia; 2008). In adolescents there is evidence that NAFLD is increasing in prevalence in Europe and other developed countries, and that NAFLD is associated with carotid IMT (Demircioglu, J Pediatr Gastroenterol Nutr; 2008 and Pacifico, Pediatr Res; 2008), dyslipidemia, hypertension, and insulin resistance (Schwimmer, Circulation; 2008 and Loomba. Hepatology; 2009). However, the current state of art regarding the association of NAFLD with vascular measures in adolescents is based largely on clinical studies, with relatively small sample sizes and that use cross-sectional or retrospective case control study designs. Therefore there is an important need for determining the relation of NAFLD with cardiovascular measures in large population based prospective studies of adolescents. It has also been argued that studying NAFLD in pediatric populations will lead to better understanding of disease mechanisms due to the absence of years of lifestyle exacerbating factors, comorbidities and attempted therapies present in adult populations (Karpen, Hepatology; 2008).

The specific onbjectives of the grant application to the BHF are:

1. To examine associations of maternal intrauterine charateristics, change in adiposity from birth to age 15, diet from infancy to age 15 and objectively assessed physical activity from 9 to 15 with ultrasound determined NAFLD at age 17+, and with biomarker determined NAFLD at ages 15+ and 17+.

2. To examine the interrelationships between dyslipidemia, insulin resistance and NAFLD in adolescence.

3. To examine the cross sectional associations of ultrasound and biomarker diagnosed NAFLD with vascular measurements from the 17+ clinic. These would include blood pressure (including 24-hour blood pressure on a sub-sample), carotid IMT, heart rate variability and measures of cardiac structure and functioned obtained from conventional and tissue Doppler echocardiography.

4. To study the prospective association of biomarker diagnosed NAFLD (at 15+) (the outcome of our MRC grant G0801456) with vascular measures at 17+ (as detailed in objective 3 above).

5. To evaluate and compare the performance of different biomarker prediction models of NAFLD (models including only commonly used, inexpensive assays and those including more expensive less commonly preformed measures) as predictors of variation in vascular measures at 17+.

As noted above, objectives 1and 2 already have Executive approval from a previous proposal from Debbie Lawlor. Objectives 3-5 are new to this proposal