Background Little is known about the effects of maintaining healthy sleep patterns on frailty transitions. Methods Based on 23,847 Chinese adults aged 30–79 in a prospective cohort study, we examined the associations between sleep patterns and frailty transitions. Healthy sleep patterns included sleep duration at 7 or 8 h/d, without insomnia disorder, and no snoring. Participants who persisted with a healthy sleep pattern in both surveys were defined as maintaining a healthy sleep pattern and scored one point. We used 27 phenotypes to construct a frailty index and defined three statuses: robust, prefrail, and frail. Frailty transitions were defined as the change of frailty status between the 2 surveys: improved, worsened, and remained. Log-binomial regression was used to calculate the prevalence ratio (PR) to assess the effect of sleep patterns on frailty transitions. Results During a median follow-up of 8.0 years among 23,847 adults, 45.5% of robust participants, and 10.8% of prefrail participants worsened their frailty status, while 18.6% of prefrail participants improved. Among robust participants at baseline, individuals who maintained sleep duration of 7 or 8 h/ds, without insomnia disorder, and no-snoring were less likely to worsen their frailty status; the corresponding PRs (95% CIs) were 0.92 (0.89–0.96), 0.76 (0.74–0.77), and 0.85 (0.82–0.88), respectively. Similar results were observed among prefrail participants maintaining healthy sleep patterns. Maintaining healthy sleep duration and without snoring, also raised the probability of improving the frailty status; the corresponding PRs were 1.09 (1.00–1.18) and 1.42 (1.31–1.54), respectively. Besides, a dose-response relationship was observed between constantly healthy sleep scores and the risk of frailty transitions (P for trend < 0.001). Conclusions Maintaining a comprehensive healthy sleep pattern was positively associated with a lower risk of worsening frailty status and a higher probability of improving frailty status among Chinese adults.

Background Epidemiological evidence on the relationship between fish consumption and chronic obstructive pulmonary disease (COPD) is limited, especially among Chinese. Objectives To explore the prospective association between fish consumption and COPD among a large population-based Chinese cohort. Methods The China Kadoorie Biobank (CKB) recruited over 0.5 million participants from ten geographically diverse regions across China from 2004 to 2008. Consumption frequency of fish at baseline was assessed by a validated food frequency questionnaire. 169,188 men and 252,238 women who had no prior COPD and other major chronic diseases at baseline were included in our analyses. Cox proportional hazard models were employed to estimate the hazard ratio (HR) and 95% confidence interval (CI) for fish consumption categories in relation to incident COPD. Results During a median follow-up of 11.1 years, 5542 incident COPD cases were documented. Fish consumption was inversely associated with COPD risk among women, with a 17% reduction in risk for participants who consumed fish ≥4 days/week compared with non-consumption (HR: 0.83; 95% CI: 0.70, 0.99; p for trend = 0.017), whereas we did not observe such a dose-response relationship among men (HR: 0.89; 95% CI: 0.76, 1.05; p for trend = 0.373). The joint analysis showed that COPD risk was 38% and 48% lower in men and women who consumed fish ≥4 days/week and had a healthy lifestyle (having ≥4 of the following healthy lifestyle factors: not smoking currently, never or rarely drinking alcohol, adequate physical activity, BMI 18.5-23.9 kg/m2, normal waist circumference, reasonable diet), compared with participants with fish consumption &lt;4 days/week and unhealthy lifestyle (≤1 factors). Conclusion Higher fish consumption was associated with lower COPD risk among Chinese women but not men. Such association was independent of lifestyle factors. Eating adequate fish with an overall healthy lifestyle might help to lower the risk of COPD.

Little is known about the effect of age at first childbirth on lung function. We aimed to investigate the association between age at first childbirth and lung function in Chinese women and further test whether this association is mediated by body mass index (BMI). Methods: This cross-sectional study is a partial survey of the China Kadoorie Biobank (CKB) which was conducted in Xinxiang City, Henan Province between 2004 and 2008. A total of 16,584 postmenopausal women aged 30-79 years were enrolled. Multiple linear and logistic regression were used to investigate the association between age at first childbirth and lung function and overweight/ obesity. The mediation analysis was performed using the PROCESS procedure for SPSS. Results: The mean (SD) age at first childbirth was 23.1 (2.7) years. Women with first childbirth aged ≤19 years and 20-22 years had lower lung function than women who gave first childbirth aged 23-25 years. Per 1-year increase in the age at first childbirth was associated with a 3.31 mL increase in FEV1 (95% CI = 1.27-5.35), 3.91 mL increase in FVC (95% CI = 1.63-6.18), 0.15% increase in FEV1, % predicted (95% CI = 0.05-0.24) and 0.14% increase in FVC, % predicted (95% CI = 0.05-0.22). There was no clear association between age at first childbirth and FEV1/FVC ratio. BMI played a contribution to the association between age at first childbirth and FEV1 and the proportion was 16.4% (indirect effect: β = 0.65, 95% CI = 0.46-0.89; total effect: β = 3.96, 95% CI = 1.92-5.99). Similarly, the proportion to FVC, FEV1, % predicted, and FVC, % predicted was 25.0%, 16.6%, and 25.0%, respectively. Conclusion: Early age at first childbirth was associated with lower lung function and BMI mediated the association. It is important to test lung function and popularize the knowledge of weight control in women who gave first childbirth at an early age.