Background: Data describing the effects of weight change across adulthood on asthma are important for the prevention of asthma. This study aimed to investigate the association between weight change from early to middle adulthood and risk of incident asthma. Methods: Using data from the National Health and Nutrition Examination Survey (NHANES), we performed a nationally retrospective cohort study of the U.S. general population. A total of 20,771 people aged 40–74 years with recalled weight at young and middle adulthood were included in the cohort. Four weight change groups were categorized: stable non-obesity, non-obesity to obesity, obesity to non-obesity, and stable obesity. Hazard ratios (HRs) and 95% confidence intervals (CIs) relating weight change to incident asthma over 10 years of follow-up were calculated using Cox models adjusting for covariates. Results: Compared with the stable non-obesity group, the HRs of incident asthma were 1.63 (95% CI = 1.29 to 2.07, P < 0.001) for the non-obesity to obesity group, 1.41 (95% CI = 0.97 to 2.05, P = 0.075) for stable obesity group, and 1.21 (95% CI = 0.41 to 3.62, P = 0.730) for the obesity to non-obesity group. In addition, participants who gained more than 20 kg from young to middle adulthood had a HR of 1.53 (95% CI = 1.15 to 2.03, P = 0.004), compared with those whose weight remained stable (weight change within 2.5 kg). Conclusions: Weight gain from early to middle adulthood was associated with higher risk of incident asthma as compared to those who maintained normal weight. Thus, maintaining normal weight throughout adulthood might be important for the primary prevention of adult-onset asthma.
Background: The effect of obesity in early adulthood and weight loss on incident hypertension in older age has not been well characterized. This study aimed to examine the association of weight loss from young adulthood to midlife with risk of incident hypertension later in life. Methods: We performed a retrospective cohort study using data from the National Health and Nutrition Examination Survey (NHANES). Five weight change groups were categorized: stable normal, weight loss, weight gain, maximum overweight and stable obese. The hazard ratios (HRs) and 95% confidence intervals (CIs) of the association between weight change and risk of hypertension in later life were estimated using Cox regression models. Results: Compared with participants who maintained normal weight, the stable obese, weight gain, maximum overweight and weight loss groups exhibited significantly higher risks of incident hypertension, with HR of 3.28 (95% CI = 2.71 to 3.96), 2.93 (95% CI = 2.62 to 3.28), 1.76 (95% CI = 1.55 to 2.00) and 1.97 (95% CI = 1.17 to 3.31), respectively. We also observed a lower risk among those in the weight loss group (HR = 0.60, 95% CI = 0.35 to 1.02) compared with those who were stable obese. Conclusions: Weight loss from early to middle adulthood was associated with lower risk of incident hypertension as compared to those who stayed obese and higher risk of incident hypertension as compared to those who maintained normal weight. Thus, maintaining normal weight throughout adulthood may be important for the primary prevention of hypertension.
1 January 2016 in Japanese Journal of Infectious Diseases
Hemorrhagic fever with renal syndrome (HFRS) is highly endemic in mainland China, where human cases account for 90% of the total global cases. Zibo City is one of the most seriously affected areas in Shandong Province, China. Therefore, there is an urgent need for monitoring and predicting HFRS incidence in Zibo to make the control of HFRS more effective. In this study, we constructed an autoregressive integrated moving average (ARIMA) model for monthly HFRS incidence in Zibo from 2004 to 2013. The ARIMA (3,1,1) × (2,1,1)12 model is reliable with a high validity, which can be used to predict the next year's HFRS incidence in Zibo. The forecast results suggest that the HFRS incidence in Zibo will experience a slight growth in the next year.
11 June 2020 in Journal of Epidemiology and Community Health
Background: China has been facing nationwide air pollution at unprecedented high levels primarily from fossil–fuel combustion in the past decade. However, few studies have been conducted on the adverse effect of severe air pollution on lung development in school-age children. Methods: Using wellness check and air pollution data from 2014 to 2017, we conducted a retrospective analysis of lung development in 21 616 school-age children from Shijiazhuang and Qingdao from North China with severe vs mild air pollution. Linear mixed effects model was performed to assess the effect of air pollution on forced vital capacity (FVC) growth. Results: Exposure to severe air pollution was associated with a dramatic reduction in annual FVC growth rate (−71.3 mL, p< 0.001). In addition, every 10 μg/m3 increase in annual PM2.5 level was associated with a reduction of annual FVC growth by 12.2 mL ( p< 0.001). Sex discrepancy (boys vs girls) in FVC growth was greater in Qingdao (35.4 mL/year, 95% CI: 26.0 to 44.7) than in Shijiazhuang (19.8 mL/year, 95% CI: 9.3 to 30.3) (p for interaction=0.063). Exposure to indoor coal- or wood-burning stove heating (−79.4 mL, p< 0.001) and secondhand smoke at home (−59.3 mL, p= 0.003) were inversely associated with FVC growth. Conclusion: Our study raised serious alarm over the threat of severe air pollution to lung development in school-age children. Sex discrepancy in lung development was reduced dramatically in heavily polluted area.