ObjectiveTo investigate the influence of demographic and socioeconomic factors on the COVID-19 case-fatality rate (CFR) globally.DesignPublicly available register-based ecological study.SettingTwo hundred and nine countries/territories in the world.ParticipantsAggregated data including 10 445 656 confirmed COVID-19 cases.Primary and secondary outcome measuresCOVID-19 CFR and crude cause-specific death rate were calculated using country-level data from the Our World in Data website.ResultsThe average of country/territory-specific COVID-19 CFR is about 2%–3% worldwide and higher than previously reported at 0.7%–1.3%. A doubling in size of a population is associated with a 0.48% (95% CI 0.25% to 0.70%) increase in COVID-19 CFR, and a doubling in the proportion of female smokers is associated with a 0.55% (95% CI 0.09% to 1.02%) increase in COVID-19 CFR. The open testing policies are associated with a 2.23% (95% CI 0.21% to 4.25%) decrease in CFR. The strictness of anti-COVID-19 measures was not statistically significantly associated with CFR overall, but the higher Stringency Index was associated with higher CFR in higher-income countries with active testing policies (regression coefficient beta=0.14, 95% CI 0.01 to 0.27). Inverse associations were found between cardiovascular disease death rate and diabetes prevalence and CFR.ConclusionThe association between population size and COVID-19 CFR may imply the healthcare strain and lower treatment efficiency in countries with large populations. The observed association between smoking in women and COVID-19 CFR might be due to the finding that the proportion of female smokers reflected broadly the income level of a country. When testing is warranted and healthcare resources are sufficient, strict quarantine and/or lockdown measures might result in excess deaths in underprivileged populations. Spatial dependence and temporal trends in the data should be taken into account in global joint strategy and/or policy making against the COVID-19 pandemic.

BackgroundThe association between ages and psychological impact of natural disasters has not been well characterized. A population-based study was conducted 15 months after the 2008 Sichuan earthquake to assess whether elderly survivors were more likely to develop posttraumatic stress disorder (PTSD) and general psychiatric morbidity.MethodsA population-based survey of 327 survivors (152 elders, 175 younger adults) was conducted in severely affected areas by the earthquake, using a multi-stage systematic sampling design.ResultsCompared with the younger adult survivors, the elderly were more likely to have symptoms of PTSD (22.5% vs. 8.0%, p = 0.001) and general psychiatric morbidity (42.0% vs. 25.4%, p = 0.003). Risk factors, such as being elderly, having been in serious danger, having lost family members, and having felt guilt concerning one's death or injury were significantly associated with developing PTSD; being elderly, having family members or friends seriously injured, and having felt guilt concerning one's death or injury were significantly associated with developing general psychiatric morbidity. Utilization of mental health services is strongly associated with the decreased risk for developing both of the symptoms.ConclusionCompared with the younger adults, the elderly survivors were more likely to develop PTSD and general psychiatric morbidity. More mental health services should be distributed to the elderly and groups at particular risk, to ensure their smooth mental health reconstruction after the earthquake.

In the United States, about 25% of infant formula sold is based on soy protein, which is an important source of estrogenic isoflavones in the human food supply. Nevertheless, few studies report isoflavone levels in infants. We did a partly cross-sectional and partly longitudinal pilot study to examine children's exposure to isoflavones from different feeding methods. A total of 166 full-term infants between birth and 1 year of age were recruited into soy formula, cow milk formula, or breast milk regimens according to their feeding histories. A total of 381 urine, 361 saliva, and 88 blood samples were collected at 382 visits. We used automated online solid-phase extraction coupled to high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) for measuring three isoflavones (daidzein, genistein, and equol) in urine, and used similar LC/MS/MS techniques for saliva and blood spots. Concentrations of daidzein and genistein were undetectable in most blood or saliva samples from children fed breast milk or cow milk formula. The proportion of non-detectable values was somewhat lower in urine than in the other matrices. Concentrations of equol were detectable only in a few urine samples. For both daidzein and genistein, urine contained the highest median concentrations, followed by blood and then saliva. Urinary concentrations of genistein and daidzein were about 500 times higher in the soy formula-fed infants than in the cow milk formula-fed infants. The correlations between matrices for either analyte were strikingly lower than the correlation between the two analytes in any single matrix. We did not find significant correlations between isoflavone concentrations and the levels of certain hormones in children fed soy formula. Our results, based on much larger numbers of infants, strongly confirm previous reports, but whether phytoestrogens in soy formula are biologically active in infants is still an open question. We plan further longitudinal studies focusing on physical and developmental findings reflecting the effects of estrogen exposure.