Associations of abdominal obesity-related dietary patterns with prediabetes and type 2 diabetes: exploring the mediating effects of body composition and altitude in Tibetan adults

Abstract Objectives: To investigate the association of dietary patterns (DP) with prediabetes and type 2 diabetes (T2D) among Tibetan adults, first to identify DP associated with abdominal obesity and examine their relationships with prediabetes and T2D. Additionally, the study aims to investigate the mediating effects of body fat distribution and altitude on the associations between these DP and the prevalence of prediabetes and T2D. Design: An open cohort among Tibetans. Setting: Community-based. Participants: The survey recruited 1003 participants registered for health check-ups from November to December 2018 and 1611 participants from December 2021 to May 2022. During the baseline and follow-up data collection, 1818 individuals participated in at least one of the two surveys, with 515 of them participating in both. Results: Two DP were identified by reduced rank regression. DP1 had high consumption of beef and mutton, non-caloric drink and offal and low intake in tubers and roots, salty snacks, onion and spring onion, fresh fruits, desserts and nuts and seeds; DP2 had high intake of whole grains, Tibetan cheese, light-coloured vegetables and pork and low intake of sugar-sweetened beverages, whole-fat dairy products and poultry. Individuals in the highest tertile of DP1 showed higher risks of prediabetes (OR 95 % CI) 1·35 (1·05, 1·73) and T2D 1·36 (1·05, 1·76). The highest tertile of DP2 exhibited an elevated risk of T2D 1·63 (1·11, 2·40) in full adjustment. Conclusion: Abdominal adiposity-related DP are positively associated with T2D. Promoting healthy eating should be considered to prevent T2D among Tibetan adults.