[Characteristics of daytime napping and its correlation with chronic diseases in Chinese adults].

Objective: To describe the prevalence of daytime nap habit in participants of the China Kadoorie Biobank (CKB) study, across 10 study regions and explore its correlation with prevalence of major chronic diseases. Methods: Participants with a self-reported pre-diagnosis of any cancer at baseline survey were excluded. Logistic regression models were used to analyze the differences in study regions and age distribution of the prevalence daytime nap habit, and its correlation with the prevalence of diabetes, hypertension, coronary heart disease (CHD), stroke, chronic obstructive pulmonary disease (COPD), and chronic liver diseases. Results: Among 510 145 participants, 39.9% had daytime nap habit in summer and 20.8% had daytime nap habit all the year round. Urban-rural differences were observed in the prevalence of summer nap habit and perennial nap habit. Daytime nap in summer was common in rural areas and Suzhou, with prevalence ranged from 32.9% to 73.3%. Haikou and Liuzhou had higher prevalence of perennial nap (60.4% and 63.3%). The proportion of people with daytime nap habit all the year round increased with age (P for trend <0.001), the proportion was highest in those aged 70- years (31.9%). Daytime nap habit in summer was positively correlated with the prevalence of diabetes, hypertension, CHD and chronic liver disease with OR of 1.10 (95%CI: 1.07-1.14), 1.03 (95%CI:1.02-1.05), 1.07 (95%CI: 1.02-1.12) and 1.07 (95%CI:1.00-1.14), respectively. Daytime nap habit all the year round was positively correlated with the prevalence of diabetes, hypertension, CHD, stroke, COPD and chronic liver disease with OR of 1.33 (95%CI: 1.29-1.37), 1.11 (95%CI: 1.09-1.13), 1.39 (95%CI: 1.33-1.45), 1.33 (95%CI: 1.26-1.41), 1.12 (95%CI: 1.08-1.16) and 1.27 (95%CI:1.18-1.37) respectively. Conclusion: There were regional and age differences in prevalence of daytime nap habit among CKB participants. Daytime nap habit, especially daytime nap habit all the year round, was positively correlated with the prevalence of major chronic diseases.

[Spicy food consumption and risk of lip, oral cavity and pharynx cancers: a prospective cohort study of Chinese adults].

Objective: To explore the association of spicy food consumption and risk of lip, oral cavity, and pharynx cancers (LOCPs) in Chinese adults. Methods: Based on the baseline survey and long-term follow-up of the China Kadoorie Biobank (CKB) study, Cox proportional hazard regression models were used to estimate hazard ratios (HR) and 95% confidence intervals (95%CI) for associations between spicy food consumption and LOCPs incidence. Results: Of the 510 145 participants included at baseline, 30.1% reported daily spicy food consumption. During a mean follow-up of 10.8 (2.0) years, we documented 767 LOCPs cases. Multivariate adjusted analyses showed that the risk of LOCPs incidence decreased with the frequency of spicy food intake (trend P=0.003), with HR of 0.69 (95%CI:0.54-0.88) for daily spicy food consumers, compared with never or occasional consumers. Participants who preferred moderate pungency degrees had the lowest risk of LOCPs, with a 33%[0.67(95%CI:0.52-0.87)] reduced risk compared to those who consumed spicy food less than once per week. The later the starting age, the lower the risk (trend P=0.004). Those who started eating spicy food after 18 years old had the lowest risk of LOCPs incidence, with adjusted HR (95%CI) of 0.70(0.54-0.92). Conclusions: Spicy food intake might be associated with a decreased risk of LOCPs incidence. Such association was independent of healthy lifestyles. Advocating moderate-pungency spicy food consumption and healthy lifestyles might help prevent LOCPs.