Healthy dietary patterns in relation to multimorbidity among schoolteachers

Background: Dietary quality has been associated with the development of several chronic diseases. However, few studies have evaluated the association between dietary quality and the co-existence of two or more chronic conditions. Methods: We conducted a cross-sectional analysis among 10 781 schoolteachers (mean age 39.3 ± 9.4 years, 74.4% female) in China. Dietary quality was assessed by five dietary scores, including the Chinese Healthy Eating Index (CHEI), Dietary Approaches to Stop Hypertension (DASH), alternate Mediterranean Diet (aMED), healthful Plant-based Diet Index (hPDI), and Mediterranean-DASH Diet Intervention for Neurodegenerative Delay (MIND) diet. Multimorbidity was defined as the co-existence of two or more chronic conditions, including coronary heart disease, stroke, diabetes, hypertension, hyperlipidemia, cancer, depressive symptoms, and anxiety symptoms. Logistic regression models were used to evaluate the corresponding associations. Results: A total of 1892 (17.5%) participants were classified as having multimorbidity. Compared with participants in the lowest tertile, those in the highest tertile of dietary scores were associated with lower odds of multimorbidity (Odds Ratio [OR] = 0.67, 95% Confidence Interval [CI], 0.59-0.76 for CHEI; OR = 0.76, 95% CI, 0.66-0.87 for aMED; OR = 0.77, 95% CI, 0.68-0.87 for MIND; OR = 0.81, 95% CI, 0.71-0.92 for DASH; OR = 0.86, 95% CI, 0.76-0.98 for hPDI). The associations persisted across major subgroups by age, gender, income level, smoking status, and physical activity. In terms of specific chronic conditions, higher adherence to all five healthy dietary patterns was associated with lower odds of depressive symptoms and anxiety symptoms, whereas CHEI and DASH were associated with lower odds of cardiometabolic diseases. In particular, intake of fresh vegetables was inversely associated with multimorbidity, whereas sugar-sweetened beverages, sodium, and alcohol consumption demonstrated detrimental associations with multimorbidity. Conclusions: Our findings support the potential beneficial role of healthier dietary patterns in maintaining the overall health among Chinese schoolteachers.