Understanding delayed effects on health of COVID-19 & lockdown

The year is 2045 and Balu, who is 25-years-old, has begun to talk and behave strangely. It is apparent, fairly soon, that he has a major mental illness. He is taken to a psychiatrist, a diagnosis of schizophrenia is made, and an antipsychotic drug is prescribed. Balu will need to continue antipsychotic treatment for months to years, and possibly for life. This is bad news for the family because, just a year earlier, his mother, aged 50 years, was found to have diabetes and high blood pressure, and his father, aged 60 years, suffered a stroke.

Could all of this bad news have arisen from a single black swan event, the COVID-19 pandemic that swept across the world during 2020, and the lockdown that was declared during the pandemic? The answer, surprisingly, is yes.

Almost everybody knows that COVID-19 is a serious respiratory disease that is characterised by fever, cough, difficulty in breathing, and other symptoms. Almost everybody knows that, during the lockdown, people are anxious, restless, irritable, and uneasy, and that some may worry themselves into depression. However, few people realise that COVID-19 and the lockdown can result in delayed harms to health, some of which may arise even decades later.

Delayed medical consequences

Starting with something that's rather obvious, lockdown means no going out, no exercise, a lot of watching TV and snacking, eating some more, and gaining weight. Weight gained is notoriously hard to lose; we only have to look around us, or consider personal experience, to realise how true this is. In persons who gain, say, 4-5 kg or more, the weight gain would be associated with an increased risk of a large number of health problems, including diabetes, high blood pressure, heart disease, stroke, osteoarthritis of the knee joints, Alzheimer's disease, and different types of cancer.

Because the adverse health outcomes occur years to decades later, and because these health disorders are also a result of several other contributory causes, few would realize how weight gain during COVID-19 lockdown might have added to the risk.

Delayed mental health consequences

There is more than half a century of hard research that demonstrates that stress of any nature increases the risk of major and minor mental illness; the risk of mental illness is greater when people find it hard to adjust to the stress. The risk of mental illness is increased not just in the immediate future but even years after the stress has passed. In a way, this is like imprinting a vulnerability into neuronal circuits.

This means that the adaptative demands necessitated by the COVID-19 pandemic and the lockdown may result in a surge in new cases of major and minor mental illness in the coming months and also in the coming years. It goes without saying that there is a risk of worsening or relapse in persons with existing mental illness. The stress can also tip vulnerable persons into alcohol and illicit substance abuse.

As a side note, many patients with existing mental illness may be unable to get their medicines during the lockdown; this is especially true among those, in poorer segments of society, who depend on the free medicines dispensed by hospitals that are now closed. Patients who are unable to continue their medicines are at high risk of relapse.

Persons who develop COVID-19 and require intensive (ICU) care, and especially those who require ventilatory support and later recover, would have been in fear of death. These patients are at high risk of developing a condition called posttraumatic stress disorder (PTSD), a condition that was first described in military veterans who had survived combat.

Last but not the least

Last but not least, viral infections during pregnancy have long been known to increase adverse pregnancy outcomes. An infection during early pregnancy may cause anything from spontaneous abortion to a malformed baby. An infection late in pregnancy can increase the risk of neurodevelopmental disorders such as attention-deficit hyperactivity disorder, autism, or intellectual disability. An infection late in pregnancy can even increase the risk of schizophrenia in the child, decades later, such as during early adult life.

It is too early to say whether the COVID-19 virus can cause all of these, but it would be optimistic to believe that the virus would have no harmful effects, either. As of now, a small body of evidence suggests that the virus is indeed transmitted from mother to child, possibly across the placenta, which implies that all of the risks listed above are possible.

Parting note: How large are the risks?

Readers may reasonably ask how large these risks are. The risk of PTSD may be as high as 10 to 50 per cent in the months after discharge from the ICU; the more stressful the events in the ICU, the higher the risk. At the other extreme, there is only a few percentage points increase in the risk of medical complications, years to decades ahead, or of neurodevelopmental or other complications related to pregnancy exposure to the disease, again years to decades ahead.

This is like saying that there is a 95 per cent or greater chance that, for example, the baby will be born normal and will remain normal all through adult life. So, at an individual level, these risks are low. However, at a population level the risk is substantial. What does this mean?

COVID-19 is associated with death in only two to five per cent of cases. So there is a 95 per cent chance, or greater, of surviving the disease; this is very good. However, for the population, a two to five per cent death rate is unacceptably high, which is why the government panicked the country into a lockdown. In like manner, a few percentage points increase in delayed-onset of medical or psychiatric illness is of serious concern for public health, and the healthcare system will need to be prepared for it.

(Dr Chittaranjan Andrade is Dean, National Institute of Mental Health and Neurosciences, Bengaluru)

The views expressed above are the author’s own. They do not necessarily reflect the views of DH.