A study comparing the COVID-19 mortality rate in the first and second waves of the coronavirus pandemic in India found that the mortality rate increased by nearly 40 percent in the second wave, which hit the country over April and May 2021.
The study, conducted by private hospital chain Max Healthcare across its nine hospitals in five northern states, analysed data from 14,398 patients admitted in the first wave versus 5,454 in the second wave. Specifically, the study was conducted based on data from hospitals in Delhi-NCR, Mohali, Dehradun, and Bhatinda.
It also said that the highest rate of mortality was among people younger than 45 years of age. The study, published in the MedRxiv journal, is yet to be peer-reviewed.
Max Healthcare group medical director Dr Sandeep Budhiraja was quoted as saying, “This is one of the largest studies from India on clinical profile of hospitalised COVID-19 patients. And, we have looked at various parameters such duration of hospitalisation, need for oxygen, treatments given, and laboratory markers.”
What did the study on COVID-19 mortality rate find?
The overall COVID-19 mortality rate jumped from 7.2 percent in the first wave to 10.5 percent in the second wave, the study stated. This increase was seen in both men (10.8 percent from 7.4 percent) and women (9.8 percent from 6.8 percent).
Younger patients saw the sharpest increase in mortality during the second wave. The figure rose from 1.3 percent in the first wave to 4.1 percent in the second wave.
Additionally, it was observed that the average duration of symptoms prior to admission — that is, the severity of the hospital was 7.3 days in the second wave versus 6.3 days in the first wave.
Demographic-wise, the mortality was high among both men and women in the age group under 45 years. In men it rose from 1.4 percent in the first wave to 4.7 percent in the second wave, whereas women showed a mortality rate of 2.8 percent, up from 1.0 percent in the first wave.
Sex differentials in other age group were not significant, News18 reported.
The trend of increased mortality was seen across all the other age groups too: 45-59 years (from 5 percent to 7.6 percent), 60-74 years ( from 12 percent to 13.8 percent), and in ≥ 75 years it was from 18.9 percent to 26.9 percent.
The higher mortality rates during the second wave were seen across various treatment modalities; whether the patients were on non-invasive ventilator (NIV) (from 40.8 percent in the first wave to 48.4 percent in the second wave); invasive ventilator (from 62.5 percent in the first wave to 68.4 percent in the second wave) and even for those who were not on any ventilator support and those who received convalescent plasma (from 21.3 percent in the first wave to 27.6 percent in the second wave).
Not only was the mortality rate higher in the second wave for patients in ICU — it increased from 19.8 percent to 25.1 percent, but steeply higher for those admitted in wards (from 0.5 percent in the first wave to 3.1 in the second wave).
Comorbidities were more commonly present in patients in second wave (59.7 percent) than in second wave (54.8 per cent). In particular, during the second wave, diabetes, hypertension and chronic kidney disease were significantly more common but not coronary artery disease.
On the other hand, despite the severity of infection in COVID-19 patients, the duration of hospitalisation reduced from nine to eight days, the study said.
“This is the average; duration of hospitalisation was much longer for severe cases. This is likely the result of another policy change by the government. Initially, patients were required to get two consecutive RT-PCR negative report before discharge; now it is no longer needed or encouraged,” Budhiraja was quoted as saying by Hindustan Times.
Why is the mortality rate likely to have risen?
The second wave of COVID-19 greatly tested and strained India’s healthcare system. Hospitals across the country, irrespective of whether they were in urban or rural areas, were struggling to cope with the volume of COVID-19 patients, a large proportion of which also required critical care.
At the peak of the second wave over the last week of April and first week of May, hospitals were sending out SOS messages on social media and were approaching high courts seeking a boost in their supply of medical oxygen.
A number of deaths in the wards were reported due to the unavailability or shortage of beds, as hospital admissions were getting delayed for as long as a day in the second wave.
Severe COVID-19 patients who needed oxygen support were also treated in the wards instead of the ICU.
Budhiraja was also quoted by The Times of India as saying, “There was a three-fold increase in deaths due to COVID-19 among the younger patients (>45 years) who required hospitalisation.
“The healthcare infrastructure was completely overwhelmed in the second wave. Many people couldn’t find a bed in time. This could have contributed to complications and even deaths.”
The study found that oxygen requirement rose by 74 percent in the second wave, which means nearly three of four hospitalised COVID-19 patients required oxygen support.
The surge of the highly-transmissible Delta strain of COVID-19 was a contributing factor to the rapid pace and wide-ranging extent of infections in the second wave. The mutant coronavirus, labelled as a ‘Variant of Concern’ by the World Health Organization, was first identified in India.
Lastly, secondary diseases and COVID-19 related complications like the black fungus disease also compounded the problem and added to the rate of mortality.
With inputs from agencies