Physical Activity and Liver Cancer Risk: A Systematic Review and Meta-analyses.

OBJECTIVE: Liver cancer is the second most common cause of death from cancer. Physical activity (PA) was found to be associated with lower risks of several types of cancer. However, the association between PA and the risk of liver cancer is still inconclusive. This systematic review and meta-analysis was aiming to summarize the association between PA and liver cancer risk. METHODS: Literatures related were identified by searching PubMed, EMBASE, and Chinese Biomedical literature database from 1965 to 2017 without language limitation. Meta-analyses were performed using random effect model. RESULTS: A total of 5 cohort studies involving 2 513 975 subjects were identified. The pooled relative risk of leisure-time PA with liver cancer risk was 0.92 [95% confidence interval (CI), 0.84-1.01]. There is no significant association between leisure-time PA and liver cancer risk. However, leisure-time PA significantly reduced liver cancer risk in never smokers. The pooled hazard ratio of daily total PA with liver cancer risk was 0.75 (95% CI, 0.66-0.86). CONCLUSIONS: Daily total PA significantly reduces liver cancer risk, whereas leisure-time PA significantly reduces liver cancer risk only in never smokers.

[Prevalence of chronic obstructive pulmonary disease in Ningxia Hui Autonomous Region of China].

OBJECTIVE: To investigate the prevalence of chronic obstructive pulmonary disease (COPD) and its current status of diagnosis and management in Ningxia Hui Autonomous Region of China. METHODS: Using multi-stage cluster random sampling, all residents 40 years of age or older in Dawukou, Yinchuan, Wuzhong, and Jingyuan were randomly selected and interviewed with a standardized questionnaire. Spirometry was performed in all eligible participants and COPD diagnosis was made according to the spirometric criteria. The categorical variables were described by the constituent ratio or prevalence and compared by χ(2) test. RESULTS: Among 4626 sampling subjects, 4055 participants completed the questionnaire and spirometry. The mean age was (56 ± 12) years. The overall prevalence of COPD was 8.9% (360/4055). The prevalence was significantly higher in males [13.0% (243/1869)] than in females [5.4% (117/2186)]. The prevalence of COPD was significantly higher in residents of Han nationality, rural residents and smokers (χ(2) = 4.10 - 94.65, P < 0.05 and P < 0.01). There was no significant difference in COPD prevalence among different regions of Ningxia; 8.7% (76/878), 8.1% (93/1142), 8.8% (90/1019) and 9.0% (101/1016) in Dawukou, Yinchuan, Wuzhong, and Jingyuan (χ(2) = 2.12, P > 0.05), respectively. Only 23.6% (85/360) of the COPD cases was diagnosed and only 23.3% (84/360) was treated. By lung function measurements, gradeII COPD accounted for 64.2% (231/360) of the cases. CONCLUSIONS: The prevalence of COPD in Ningxia was 8.9% (360/4055) in people 40 years of age or older. The current status of diagnosis and management of COPD in this region was far from satisfactory. It was necessary to strengthen the awareness of the importance of pulmonary function tests and early intervention of COPD.