About 30% of COVID patients’s deaths in Japan’s 6th wave caused by other factors

The Yomiuri Shimbun

Among deaths related to COVID-19 in the ongoing sixth wave of novel coronavirus infections, about 30% were not directly caused by symptoms of the disease but by other factors such as worsening of preexisting conditions among elderly patients, according to analyses by some local governments.

The Health, Labor and Welfare Ministry requests that local governments report the number of deaths of all COVID-19 patients as “COVID-related deaths” regardless of their direct causes.

According to a Yomiuri Shimbun tally based on data compiled by local governments, the total number of COVID-related deaths in Japan since January was 7,885 as of Monday. This is 2.6 times the number in the fifth wave of infection that ran from August through October last year, which totaled 3,073.

In Okayama Prefecture, where 66 COVID patients had died in the sixth wave by the end of February, the prefectural government interviewed public health centers and analyzed the “direct cause of death” listed on death certificates filled out by medical institutions. The results showed that, while 68%, or 45 patients, died of coronavirus, 32%, or 21 patients, died of other factors, including aspiration pneumonia.

In the fourth wave of infections last spring, however, 90 patients’ deaths were directly attributed to COVID, while just one patient was listed as having died from other causes.

“Previously, COVID deaths were often caused by worsening pneumonia symptoms leading to breathing difficulties, but this is becoming less common in the sixth wave,” said an Okayama prefectural official. “On the other hand, the number of deaths caused by pre-existing illnesses, worsened due to deteriorating health conditions caused by the infection, is increasing rapidly.”

According to an analysis by the Chiba prefectural government, the number of COVID-related deaths not directly caused by the infection was 10%, or 24 cases, in the third wave, whereas it stands at 22%, or 39 cases, in the current sixth wave.

In Osaka Prefecture, 39% of COVID patients’ deaths, or 314 out of 799 cases in the sixth wave as of Feb. 26, were not directly caused by the symptoms of the disease.

In Kanagawa Prefecture as well, out of the 312 COVID patients’ deaths in hospitals in January and February, 100 patients, or 32%, died due to causes other than COVID symptoms.

Prof. Hiroyuki Kunishima of St. Marianna University School of Medicine, who specializes in infectious diseases, pointed out: “Although the omicron variant of the coronavirus spreading during the sixth wave is less likely to cause serious symptoms, the risk of death due to deteriorating physical strength increases if elderly people and people with preexisting illnesses, or those tending toward obesity, become infected.”

“We cannot let our guard down even if COVID symptoms are mild,” said a Kanagawa prefecture official. “In addition to administering oxygen to prevent pneumonia from progressing, it is increasingly important to monitor the health of patients at high risk to respond quickly in cases such as the worsening of their preexisting illnesses.”