Age-adjusted COVID-19 mortality in state capitals in different regions of Brazil

The sharp growth in COVID-19 cases and deaths has created a heavy overburden on Brazil’s health system, especially in the cities of Manaus (Amazonas State), Rio de Janeiro, and São Paulo. The description of the pandemic’s impact has been based on absolute numbers and crude mortality rates, failing to consider the age distribution patterns in different regions of the country. This study aims to compare the crude mortality rates from COVID-19 with age-standardized rates in the state capitals and Federal District. Information on deaths was accessed in the Information System on Influenza Surveillance (SIVEP-Gripe), and the population denominators were based on the estimate provided by the Brazilian Ministry of Health. Calculation of the age-standardized rates used the estimated age structure of the Brazilian population in 2020. The results show that the highest crude rates were in Manaus (253.6/100,000) and Rio de Janeiro (253.2/100,000). Age standardization led to a major increase in the North of Brazil. The highest age-adjusted rate was in Manaus (412.5/100,000), where 33% of COVID-19 deaths occurred in individuals under 60 years of age. Mortality in Manaus over 70 years of age was double that of Rio de Janeiro and triple that of São Paulo. The use of age-adjusted mortality rates eliminates interpretative biases, clearly exposing the even greater weight of COVID-19 in the North of Brazil.

新冠确诊病例与死亡人数的急剧增长给巴西医疗系统造成了沉重负担，尤以马瑙斯（亚马孙州）、里约热内卢与圣保罗三座城市为甚。此前针对本次大流行影响的描述多基于绝对数与粗死亡率（crude mortality rates），未考虑巴西国内不同地区的年龄分布特征。本研究旨在对比巴西各州首府及联邦特区的新冠粗死亡率与年龄标化死亡率（age-standardized rates）。研究所需的死亡数据源自流感监测信息系统（Information System on Influenza Surveillance, SIVEP-Gripe），人口分母数据采用巴西卫生部发布的人口估算值。年龄标化死亡率的计算以2020年巴西人口年龄结构估算值为基准。结果显示，粗死亡率最高的地区为马瑙斯（253.6/10万）与里约热内卢（253.2/10万）。经年龄标化后，巴西北部地区的死亡率出现显著升高。年龄标化后死亡率最高的地区仍为马瑙斯（412.5/10万），该地区33%的新冠死亡病例发生于60岁以下人群。马瑙斯70岁以上人群的新冠死亡率为里约热内卢的2倍、圣保罗的3倍。采用年龄标化死亡率可消除解读偏倚，清晰揭示出新冠疫情在巴北部地区的负担更为沉重。