BackgroundIt is well established that increased internet use is related to an increased risk of musculoskeletal pain among adolescents. The relationship between internet addiction (IA), a unique condition involving severe internet overuse, and musculoskeletal pain has, however, not been reported. This study aimed to investigate the association between IA and the risk of musculoskeletal pain among Chinese college students.MethodsA cross-sectional study was conducted among 4211 Chinese college freshmen. IA status was evaluated using the 20-item Young’s Internet Addiction Test (IAT). IA was defined as internet addiction score ≥50 points. Musculoskeletal pain was assessed using a self-reported questionnaire. Multiple logistic regression analysis was performed to determine association between IA categories (normal, mild, and moderate-to-severe) and musculoskeletal pain.ResultsAmong all participants; neck, shoulder, elbow, wrist/hand, and low back and waist pain was reported by 29.2, 33.9, 3.8, 7.9, and 27.9%, respectively. The prevalence of IA was 17.4%. After adjusting for potential confounders, the results showed significant differences in the risk of musculoskeletal pain among different IA categories. The odds ratios (ORs) and 95% confidence intervals (CI) for neck pain with IA categories were 1.000 (reference), 1.451 (1.221, 1.725), and 1.994 (1.608, 2.473), respectively (P for trends: < 0.001). For shoulder pain, these were 1.000 (reference), 1.520 (1.287, 1.795), and 2.057 (1.664, 2.542), respectively (P for trends: < 0.001). For elbow pain, ORs (95% CIs) were 1.000 (reference), 1.627 (1.016, 2.605), and 2.341 (1.382, 3.968), respectively (P for trends: 0.001). Those for wrist/hand pain were 1.000 (reference), 1.508 (1.104, 2.060), and 2.236 (1.561, 3.202), respectively (P for trends: < 0.001). For low back and waist pain with severe IA categories, these were 1.000 (reference), 1.635 (1.368, 1.955), and 2.261 (1.813, 2.819), respectively (P for trends: < 0.001).ConclusionThis cross-sectional study showed that severe IA was associated with a higher risk of musculoskeletal pain in Chinese college freshmen. In future research, it will be necessary to explore causality regarding this relationship using interventional studies.

Skipping breakfast has been suggested to increase the risk of depressive symptoms, but there is no information regarding young adults. We aimed to investigate the relationship between the frequency of breakfast consumption and the risk of depressive symptoms among Chinese college students. We investigated a cross-sectional (n = 1060) and one-year prospective (n = 757) relationship between the frequency of breakfast consumption and the risk of depressive symptoms. The frequency of breakfast consumption was categorized into "≤1 time/week", "2-5 times/week", or "≥6 times/week". Depressive symptoms were assessed using the 20-item Zung self-rating depression scale (SDS) with an SDS score of ≥50 to indicate moderate to severe depressive symptoms. In the cross-sectional analysis, the adjusted odds ratios (ORs) and 95% confidence intervals (CIs) of depressive symptoms related with the breakfast consumption categories were 1.00 (reference) for ≥6 times/week, 1.761 (95% CI: 1.131, 2.742) for 2-5 times/week, and 3.780 (95% CI: 1.719, 8.311) for ≤1 time/week (p for trend: <0.001) after adjusting for these potential confounders. Similarly, in the one-year prospective analysis, we found that 10.2% of participants was classified as having moderate to severe depressive symptoms. Multivariate logistic regressions analysis revealed a significant negative relationship between the frequency of breakfast consumption and the risk of depressive symptoms. The ORs (95% CI) for depressive symptoms with decreasing breakfast consumption frequency were 1.00 (reference) for ≥6 times/week, 2. 045 (1.198, 3.491) for 2-5 times/week, and 2.722 (0.941, 7.872) for ≤1 time/week (p for trend: 0.005). This one-year prospective cohort study showed that skipping breakfast is related to increased risk of depressive symptoms among Chinese college students. Future research using interventional or experimental studies is required to explore the causal relationship between the effects of breakfast consumption and depressive symptoms.

Depression is known to be correlated with increased risk for chronic obstructive pulmonary disease (COPD) in middle-aged and older adults, but there is scarce evidence regarding its association with lung function among healthy adults. Thus, we aimed to assess this association by measuring the lung function and depression severity in Chinese college students. This cross-sectional study was conducted among 3,891 college students aged 16-24 years. Lung function was assessed by measuring the forced vital capacity (FVC) using a spirometer, and depression severity was evaluated using the 20-item Zung self-rating depression scale (SDS), with SDS scores of ≥40 and ≥45 indicating mild and moderate-to-severe depression, respectively. After adjusting for potential confounders, the geometric means of the FVC levels for the normal, mild depression, and moderate-to-severe depression groups were 3,446.1 (95% confidence interval [CI]: 3,418.6-3,470.3), 3,415.2 (95% CI: 3,357.7-3,473.8), and 3,351.0 (95% CI: 3271.5-3432.3), respectively (P for trend: 0.031). These results indicated that depression severity was independently correlated with lung function decline in Chinese college students. Future prospective cohort or interventional studies are needed to confirm the negative association between depressive symptoms and lung function and investigate its causality.