Use of quantile regression to investigate changes in the body mass index distribution of Chinese adults aged 18-60 years: a longitudinal study.

BACKGROUND: Traditional linear regression analyses have detected increasing trends in the incidence of overweight/obesity among both genders in China. However, these previous regression analyses were limited in their ability to capture cross-distribution variations among effects. The objective of our study was to analyze the change in the body mass index (BMI) distribution of adults and investigated the relationships between the key covariates and the BMI distribution. METHODS: We used longitudinal data from the China Health and Nutrition Surveys (CHNS) in 1991, 1993, 1997, 2000, 2004, 2006, 2009, and 2011, with at least two waves of data collection. In total, 17,819 participants aged 18-60 years (N = 8587 men and 9232 women) were included in the final analysis with 48,900 observations. The lambda-mu-sigma (LMS) method was used to describe changes in the BMI distribution. Separate sex-stratified longitudinal quantile regression (QR) analyses were used to investigate changes in the BMI distribution over time. RESULTS: The main characteristics of the BMI changes in both genders were that the curves shifted to the right and the distributions became wider. All of the BMI percentile curves tended to increase from 1991 to 2011, where the levels increased more in the higher percentiles. The QR analyses showed that these patterns remain consistent after adjusting for individual and community level factors. Physical activity (PA) had a negative association with BMI for both genders in all percentiles. Income and energy intake were associated with positive changes in male BMI in the upper percentile. Sedentary time had a positive association with female BMI in the middle percentile. Compared with less educated women, women with senior school education at 75(th) percentile had 0.951 kg/m(2) lower BMIs. CONCLUSIONS: This longitudinal quantile regression suggests that effects of different covariates worked differently across the BMI distribution. Since social and economic characteristics in China have underlined the significant disparities in many aspects, national strategies to tackle overweight/obesity should be tailored as appropriate for various segments.

The association between physical activity and sleep in adult ADHD patients with stimulant medication use.

Background: Adults with attention-deficit/hyperactivity disorder (ADHD) may experience sleep problems doubly suffering from the disease and side effects of stimulant medications. Physical activity (PA) is known to produce numerous beneficial effects in adults. However, it was not well-characterized whether PA would still be effective in this situation. The main objective of the current study was to examine the relationship between PA and sleep among adult ADHD patients who were using stimulant medications and quantify the form of this association. Methods: Adult ADHD participants with stimulant medications use condition from the National Health and Nutrition Examination Survey (NHANES) database between January 1, 2013, and March 2020 (prepandemic) were included in the cross-sectional analysis. Weighted logistic regression was performed to assess the relationship between PA level and sleep. A restricted cubic spline model was used to relax the linear relationship assumptions and investigate the associations between the risk of trouble sleeping and time spent engaging in moderate-to-vigorous PA per week. Results: A total of 162 eligible adult ADHD participants who reported using stimulant medicines were included. Participants who adhered to the general recommendation of guidelines in the US of 150 min per week of moderate-to-vigorous PA had a significant lower risk of complaining of trouble sleeping (OR: 0.26, 95% CI: 0.10-0.67, p = 0.006), and this association was seen in men (OR: 0.23, 95% CI: 0.09-0.56, p = 0.002), but was not seen in women (OR: 0.71, 95% CI: 0.27-1.88, p = 0.500). Restricted cubic spline analysis showed that the incidence of trouble sleeping gradually decreased after at least 105 min of moderate-intensity PA per week in participants (OR: 1.02, 95% CI: 0.92-1.14). A significant difference appeared after 341 min (OR: 0.87, 95% CI: 0.76-0.99), and the curve leveled after 1,250 min (OR: 0.60, 95% CI: 0.46-0.79). Conclusion: Our findings observed associations between PA and sleep condition in the adult ADHD patients with stimulant medication use population. Moderate-to-vigorous PA may be beneficial to sleep in adults with ADHD who were using stimulants and thus should be recommended as part of a healthy lifestyle. Gender difference should be considered as an important factor for further studies to examine these associations and explore potential mechanisms.

Risk Factors Affecting Muscle Mass Decline in Maintenance Hemodialysis Patients.

Objective: There is a high prevalence of sarcopenia in maintenance hemodialysis (MHD) patients, which is known to be associated with increased mortality. This study is aimed at analyzing the risk factors affecting muscle mass decline in MHD patients. Methods: This retrospective study included MHD patients who underwent two body composition assessments in October 2013 and November 2017. Depending on whether there was muscle loss or not, the patients were divided into a normal muscle mass (NMM) group and a muscle mass decline (MMD) group. According to the muscle mass decline rate, patients in the MMD group were further classified into a low-rate group and a high-rate group. Biochemical variables, serum vitamin concentrations, anthropometric data, SGA, muscle mass, handgrip, and daily steps were assessed. Risk factors for muscle mass decline were screened by multivariate logistic analysis and linear regression analysis. Results: Of the 72 MHD patients included in this study, 33 were male and 39 were female with a mean age of 56.80 ± 10.86 years and a mean dialysis duration of 7.50 ± 5.20 years. Age (P = .014) and serum 25(OH)D (P = .040) were found to be associated with a higher risk of muscle mass decline after adjusting for gender, dialysis vintage, albumin, and hs-CRP (P = .040). Further analysis found that dialysis vintage (ß = 0.285, P = .030), 25(OH)D (ß = -0.351, P = .007), and log NT-proBNP (ß = 0.312, P = .020) were risk factors associated with the muscle mass decline rate in MHD patients. Conclusion: Age and serum 25(OH)D were associated with a higher risk of muscle mass decline, while 25(OH)D, dialysis vintage, and NT-proBNP were associated with the muscle mass decline rate in MHD patients.

Emotional prosody recognition in children with high-functioning autism under the influence of emotional intensity: Based on the perspective of emotional dimension theory.

This paper investigated the ability of Mandarin-speaking children with high-functioning autism (HFA) to recognize the four categories of emotional prosody, namely, happiness, anger, sadness and fear, in moderate- and high-intensity emotional conditions using auditory discrimination tasks. Thirty-four children with HFA between 5 and 7 years of age and 34 typically developing (TD) controls participated in this study. In moderate-intensity conditions, children with HFA scored lower than TD children in the recognition of the four categories of emotional prosody, indicating an overall impairment. With an increase in the intensity of emotion, children with HFA showed improved accuracy for anger, decreased accuracy for happiness, but no change in accuracy for either sadness or fear. An analysis of error patterns demonstrated that unlike TD children, children with HFA were inclined to mistake happiness for anger, with the two categories differing in valence, and this inclination deepened as the intensity increased. In discriminating between sadness and fear, which have a slight arousal difference, both groups showed difficulty in moderate-intensity conditions. In high-intensity conditions, TD children were inclined to perceive stimuli as exhibiting fear, which demonstrates comparatively high arousal; thus, they were more accurate for fear, while HFA children were not sensitive to increases in arousal, showing no noticeable effect. These findings indicated that children with HFA have a mechanism distinct from that of TD children in emotional prosody recognition, exhibiting various degrees of impairment in this regard.

Discourse production of mandarin-speaking children with high-functioning autism: The effect of mental and action verbs' semantic-pragmatic features.

The present study investigated the syntactic and pragmatic performance of children with high-functioning autism (HFA) during a discourse production task with mental verbs. Children with HFA and typically developing (TD) children were matched by chronological age, verbal IQ (VIQ) and full-scale IQ (FIQ). We found that children with HFA tended to select a nominal object given a mental verb with either a nominal or clausal object. They committed few syntactic errors but generated syntactic stereotypes with mental verbs. However, this behavior was not observed with action verbs. Thus, children with HFA were specifically impaired in the argument structures of mental verbs. In pragmatic performance, children with HFA produced significantly fewer clauses or sentences with lower syntactic complexity for mental verbs than TD controls. This result might be due to the semantic-pragmatic impairment of children with HFA in the use of mental verbs. This study concludes that children with HFA were able to acquire the syntactic frames of mental verbs but were nevertheless impaired in the acquisition of pragmatic information inherent in those verbs.