PUTRA-Adol study: protocol for an observational follow-up study to assess the tracking of dietary patterns linked to cardiometabolic risk factors and its prospective relationship with non-alcoholic fatty liver disease, carotid intima-medial thickness and mental well-being during adolescence in Malaysia

INTRODUCTION: Growing evidence suggesting that dietary intakes of adolescents are generally of poor quality but not adequately assessed in relation to the early manifestation of non-communicable diseases. This study aimed; (1) to examine tracking of an empirical dietary pattern (DP) linked to cardiometabolic risk factors and, (2) to assess prospective relationships between a DP characterised by high intakes of dietary energy density (DED) and added sugar, and cardiometabolic risk factors, non-alcoholic fatty liver disease (NAFLD), carotid intima-medial thickness (CIMT) and mental well-being during adolescence.

METHODS AND ANALYSIS: The PUTRA-Adol is a prospective follow-up study that builds up from 933 Malaysian adolescents who were initially recruited from three southern states in Peninsular Malaysia in 2016 (aged 13 years then). Two sessions are planned; the first session will involve the collection of socio-economy, physical activity, dietary intakes, mental well-being, body image, risk taking behaviour, sun exposure, family functioning and menstrual (in women) information. The second session of data collection will be focused on direct assessments such as venesection for blood biochemistry, anthropometry and ultrasonography imaging of liver and bilateral carotid arteries. Z-scores for an empirical DP will be identified at 16 years using reduced rank regression. Multilevel modelling will be conducted to assess the tracking of DP and prospective analysis between the DP, cardiometabolic health, NAFLD, CIMT and mental well-being.

ETHICS AND DISSEMINATION: Ethical approval for the conduct of this follow-up study was obtained from the Universiti Putra Malaysia's Ethics Committee for Research Involving Human Subjects (JKEUPM) (Reference number: JKEUPM-2019-267). The findings from this study will be disseminated in conferences and peer-reviewed journals.

DISCUSSION: The findings gathered from this study will provide evidence on prospective relationships between DPs, cardiometabolic risk factors, NAFLD, early atherosclerosis and mental well-being and that it may be mediated particularly DED and added sugar during adolescence.