Little is known about the associations between chrononutrition and sleep behaviours with glycaemic responses. Hence, this study aimed to examine the associations between chrononutrition, sleep behaviours and glycaemic outcomes among adults with prediabetes. This was a cross-sectional study within a prospective longitudinal study in Malaysia. Data on chrononutrition, sleep behaviours and sleep quality were collected using the Malay translated Chrononutrition Profile Questionnaire, Munich Chronotype Questionnaire and Pittsburgh Sleep Quality Index Questionnaire respectively. Anthropometric measurements, body composition assessments and glycaemic measurements were obtained for all participants. Regression models were conducted to explore the associations between chrononutrition, sleep behaviours and glycaemic outcomes. A total of 142 participants with mean age of 54 ± 17 years were recruited. Consuming the first meal after 10.00 am was associated with lower odds of elevated glycaemic outcome (HbA1c ≥ 5.7%) (OR: 0.300, 95% CI: 0.107, 0.841), while having the last meal after 8.00 pm was associated with higher odds of HbA1c ≥ 5.7% (OR: 2.650, 95% CI: 1.125, 6.241). Furthermore, fasting blood glucose was positively associated with extended sleep time (β: 0.101; 95% CI: 0.001, 0.201), while higher 2-h postprandial glucose level was significantly associated with poorer sleep quality (β: 0.093; 95% CI: 0.001, 0.186). These findings demonstrate a positive association between chrononutrition, characterized by delayed meal times, and elevated HbA1c levels in individuals with prediabetes. Furthermore, extended sleep time and poor sleep quality are associated with adverse glycaemic outcomes. These results imply that postponing meal and sleep times may exacerbate glycaemic control. Therefore, further longitudinal and interventional studies are warranted to validate these findings and support the dietary guidelines. Clinicaltrial.gov trial registration: NCT05163964.
