Background Previous studies revealed inconsistent findings regarding the association between sleep duration and all-cause and disease-specific mortality. This study aimed to clarify the association of sleep duration with mortality using a large population-based prospective cohort study from the USA. Methods We used data from the National Health Interview Survey (2004–2014) linked to National Death Index records to 31 December 2015. A total of 284 754 participants aged ≥18 years were included. Self-reported sleep duration (average time slept in a 24-hour period) was categorised into seven groups: ≤4 hours, 5 hours, 6 hours, 7 hours (reference), 8 hours, 9 hours and ≥10 hours. Study outcomes included all-cause, cardiovascular disease-specific and cancer-specific mortality. Cox proportional hazards models were used to examine the association between sleep duration and mortality. Results During a median follow-up of 5.25 years, we identified 20 872 deaths, of which 4 129 were cardiovascular disease-related and 5 217 were cancer-related. Compared with 7 hours/day of sleep, both short and long sleep durations were associated with an increased risk of all-cause mortality (≤4 hours: HR=1.46, 95% CI=1.33–1.61; 5 hours: HR=1.22, 95% CI=1.13–1.32; 6 hours: HR=1.10, 95% CI=1.05–1.17; 8 hours: HR=1.22, 95% CI=1.17–1.28; 9 hours: HR=1.41, 95% CI=1.31–1.51; ≥10 hours: HR=2.00, 95% CI=1.88–2.13). Similar results were observed for cardiovascular disease-specific and cancer-specific mortality. Conclusions Our study indicates that both short (≤6 hours/day) and long (≥8 hours/day) sleep durations increase the risk of mortality compared with sleep of 7 hours/day. A normal sleep duration (about 7 hours) every day is recommended for health benefits.

Background Previous studies have shown inconsistent findings on the association between psychological distress and risk of mortality. This study aimed to address this inconsistent association using a large US population-based cohort. Methods This study used data from 1997 to 2009 US National Health Interview Survey, which were linked with National Death Index through 31 December 2011. Psychological distress was measured using Kessler-6 scale and was categorised into six groups based on scores as 0, 1–3, 4–6, 7–9, 10–12 and ≥13. Main outcomes were all-cause, cancer-specific and cardiovascular disease (CVD)-specific mortality. Analyses were completed in 2019. Cox proportional hazards models were used to determine the association between psychological distress and mortality. Results A total of 330 367 participants aged ≥18 years were included. During a mean follow-up of 8.2 years, 34 074 deaths occurred, including 8320 cancer-related and 8762 CVD-related deaths. There was a dose–response association between psychological distress and all-cause mortality. Compared with the 0 score category, adjusted HRs (95% CIs) for other categorical psychological distress scores, that is, 1–3, 4–6, 7–9, 10–12 and ≥13, were 1.09 (1.05 to 1.12), 1.22 (1.17 to 1.27), 1.38 (1.31 to 1.46), 1.49 (1.40 to 1.59) and 1.57 (1.47 to 1.68), respectively. Corresponding values for cancer-specific mortality were 1.06 (0.99 to 1.12), 1.13 (1.04 to 1.23), 1.27 (1.14 to 1.42), 1.38 (1.22 to 1.57) and 1.32 (1.15 to 1.51), respectively; those for CVD-specific mortality were 1.11 (1.05 to 1.18), 1.22 (1.12 to 1.32), 1.30 (1.17 to 1.45), 1.38 (1.20 to 1.58), and 1.46 (1.27 to 1.68), respectively. Conclusions We found a dose–response relationship between psychological distress and all-cause and cause-specific mortality, emphasising the need for early prevention strategies among individuals with potential psychological distress.

Youth violence is an important public health challenge around the world, yet the literature on this problem in low- and middle-income countries (LMICs) has been limited. The present study aims to examine the prevalence of adolescent physical fighting (defined as having been involved in at least one physical fight during the past 12 months) in selected LMICs, and its relations with potential risk factors. We included 6377 school-going adolescents aged 13–15 years from six Western Pacific (WP) countries that had recently conducted a Global School-based Student Health Survey. Information was gathered through a self-administered anonymous closed-ended questionnaire. The prevalence of adolescent physical fighting varied across countries, ranging from 34.5% in Kiribati to 63.3% in Samoa. The prevalence was higher in boys than in girls, and lower at age 15 than 13–14 years. Physical fighting was significantly associated (pooled odds ratios (ORs), 95% confidence intervals (CIs)) with smoking (1.78, 1.53–2.06), drinking (1.57, 1.33–1.85), drug use (1.72, 1.33–2.23), and missing school (1.72, 1.51–1.95). The association with physical fighting increased with increasing number of joint adverse behaviors (increased from 1.99 (1.73–2.29) for one risk behavior to 4.95 (4.03–6.07) for at least 3 risk behaviors, versus having none of the 4 risk behaviors). The high prevalence of physical fighting and the associations with risk behaviors emphasize the need for comprehensive prevention programs to reduce youth violence and associated risk behaviors.

Joint models are statistical tools for estimating the association between time-to-event and longitudinal outcomes. One challenge to the application of joint models is its computational complexity. Common estimation methods for joint models include a two-stage method, Bayesian and maximum-likelihood methods. In this work, we consider joint models of a time-to-event outcome and multiple longitudinal processes and develop a maximum-likelihood estimation method using the expectation–maximization algorithm. We assess the performance of the proposed method via simulations and apply the methodology to a data set to determine the association between longitudinal systolic and diastolic blood pressure measures and time to coronary artery disease.

INTRODUCTION: The clinical utility of metabolic dysfunction-associated steatotic liver disease (MASLD) in predicting subsequent subclinical cardiovascular damages in pediatric population remains poorly understood. METHODS: Data on 1,161 Chinese children aged 10–15 years were used to assess the longitudinal associations of MASLD with subsequent subclinical cardiovascular measures. RESULTS: Compared with relatively healthy children, children with MASLD had abnormal vascular and cardiac structures, along with reduced cardiac diastolic function at the 2-year follow-up. In addition, children with MASLD had a significantly increased risk of high carotid intima-media thickness and left ventricular hypertrophy. DISCUSSION: These findings support the clinical utility of MASLD in predicting the development of subclinical cardiovascular damages in childhood.