BACKGROUND: This study examines how the prevalence of depression and anxiety symptoms differ by socioeconomic status and explores their associations with diabetes in rural southwest China. METHODS: Data were collected from a cross-sectional health interview and examination survey of 5,005 adults aged ≥ 35 years in rural southwest China. Height, weight, waist circumference, and fasting blood glucose measurement were taken. Depression and anxiety symptoms were assessed using Zung's Self-rating Depression Scale (SDS) and Self-Rating Anxiety Scale (SAS), respectively. An individual socioeconomic position (SEP) index was constructed using principal component analysis. RESULTS: The overall prevalence of depression, anxiety, comorbid depression and anxiety symptoms, and diabetes was 5.4%, 12.8%, 4.0%, and 9.6%, respectively. Females had higher prevalence of depression (7.3% vs. 3.4%, P <
0.01), anxiety (17.4% vs. 8.1%, P <
0.01), and comorbid depression and anxiety symptoms (5.8% vs. 2.3%, P <
0.01) than males. Han ethnicity participants had a higher prevalence of depression, anxiety, and comorbid depression and anxiety symptoms than ethnic minority participants (P <
0.01). Individuals with a lower education level and lower SEP were more likely to experience depression, anxiety, and comorbid depression and anxiety symptoms (P <
0.01), while individuals with good access to medical services were more likely to exhibit depression symptoms and comorbid depression and anxiety symptoms (P <
0.05). Multivariable logistic regression analysis found that individuals with depression symptoms (OR = 1.78, 95% CI: 1.25 to 2.53), anxiety symptoms (OR = 1.66, 95% CI: 1.30 to 2.16), and comorbid depression and anxiety symptoms (OR = 1.61, 95% CI: 1.07 to 2.44) all had a greater probability of having diabetes (P <
0.01)
depression symptoms had the strongest association with diabetes prevalence (P <
0.01). CONCLUSIONS: There are significant socioeconomic differences in the prevalence of depression and anxiety in rural southwest China, and both depression and anxiety symptoms have strong associations with diabetes. Future diabetes prevention and management strategies should focus on individuals with depression, anxiety, and comorbid depression and anxiety symptoms.