Impact of extreme heatwaves on mental health in India: Experts weigh in

Despite the southwest monsoon bringing relief from the heat, the memory of summer 2024 still haunts many in India. The country, in 2024, witnessed one of the longest and most intense heatwaves in its history. Temperatures exceeding 45 degrees Celsius have had a serious impact on the populace.

The heatwave in India was both--a physical and emotional health disaster. The severe temperatures exacerbate anxiety, sadness, and violence, putting vulnerable people at risk.

As India continued to face the challenges of extreme weather, it became critical to address the mental health implications to ensure the well-being of its citizens.

The heatwave has caused tremendous suffering and worry. Prolonged exposure to high temperatures, experts say, can cause a variety of psychological issues, including anxiety, depression, and anger. For many Indians, the stifling heat has become a major source of mental stress.

Concerns over mental health as the mercury soared

Speaking to mid-day.com, Dr Sonal Anand, a psychiatrist with Wockhardt Hospitals in Mumbai's Mira Road, said that not just in India but across the globe people are concerned about the impact of rising temperature on a person's health--including mental health.

"Because of this global temperature rise, people across the globe are concerned about how this increase in temperature is affecting the health--not just physical, mental also of all, especially children and elderly," Dr Anand added that despite ongoing research, "we haven't been able to prove it on the molecular level per se".

She added that some scientists do accept there is Summer Affective Disorder, also called SAD, like winter affective disorders and said that symptoms of it could be like that of depression.

There could be an exacerbation of those past psychological problems, especially depression, anxiety, sleeping problems, and appetite problems. These are all psychologically related to heat, said Dr Sonal.

Meanwhile, Dr Shaunak Ajinkya, Consultant psychiatrist at Kokilaben Dhirubhai Ambani hospital, said that extreme heat impairs cognitive function, leading to difficulties in concentration, decision-making and problem-solving.

"The physical discomfort from prolonged exposure to high temperatures can lead to heightened stress levels. Concerns about the increasing frequency of heatwaves can contribute to eco-anxiety and fears about environmental doom. A study done in the UK showed that nearly 60 per cent of the young people surveyed were "very worried" or "extremely worried" about climate change. More than 45 per cent of those questioned said feelings about the climate affected their daily lives," said Dr Ajinkya.

Elaborating on it, Dr Ajinkya said, "Studies have shown a correlation between heatwaves and higher rates of violent crime and aggression. Even just a one or two-degree Celsius increase in ambient temperatures can lead to a 3-5 per cent spike in assaults."

During heatwaves, people are less likely to engage in outdoor activities or social interactions due to the health risks associated with extreme heat. People change their daily routines to cope with the heat, which can disrupt normal activities and social connections. This leads to social isolation, which negatively impacts mental health, he said and added that studies have found a 2.2 per cent increase in mental health-related deaths for every 1-degress Celsius rise in the average temperature.

"Many psychiatric medications (like lithium, certain antidepressants or antipsychotics with high anticholinergic effects) impair the body's ability to regulate temperature or increase sensitivity to heat, which can lead to heat intolerance and dehydration, further impacting mental health," he noted.

Vulnerable populations

Certain groups are more vulnerable to the mental health impacts of the heatwave. When asked about it, Dr Ajinkya noted that elderly people, children and those with pre-existing mental health conditions are at greater risk.

"Elderly people, children and infants have a hard time regulating their body temperature which makes them more susceptible to heat stress. Chronic health conditions like cardiovascular and respiratory diseases can aggravate due to heat causing the elderly stress," he said.

Elaborating on how those with existing mental health conditions can be affected, he said, ": Individuals with mental health conditions may have less capacity to implement coping strategies during extreme heat, which can worsen symptoms of anxiety, depression, and suicidality. Some psychiatric medications (like lithium and certain antidepressants or antipsychotics with high anticholinergic effects) affect the body's ability to regulate temperature, increasing the risk of heat intolerance and dehydration."

Dr Anshu Kulkarni, who is based in Mumbai's Bandra, said that those who are exposed to extreme weather conditions constantly or come from low-income backgrounds are also susceptible to experiencing aggravation of mental health issues due to heatwave.

"Workers who are exposed to high temperatures are known to have more psychological distress. Communities where they do not have resources to sustain and are fighting the poverty line are the most vulnerable. Some susceptibility usually seen is either environmental or genetic," Dr Kulkarni said.

Heatwave's impact on brain function

When asked about how extreme climatic conditions affect brain function, both Dr. Ajinkya and Dr. Sonal said that brain functioning gets impacted due to physiological effects.

Dr Sonal explained that during extreme heat conditions, one experiences dehydration and there is a significant loss of potassium. One of the commonly known side effects of lower potassium levels, she noted, is delirious behaviour.

Apart from that being exposed to extremely hot weather could lead to heatstroke; Dr Ajinkya noted that the heatstroke is caused because of poor blood flow to the brain due to the hot weather.

He said, "High temperatures can affect the production and regulation of neurotransmitters like serotonin and dopamine, which are crucial for mood regulation and cognitive function. Serotonin keeps levels of aggression in check. Disruption in these neurotransmitters can lead to mood disorders and impaired cognitive performance. By 2090, it is estimated that climate change could be responsible for up to a 5 per cent increase in all crime categories globally."

Mitigating the mental health impacts of heat waves

Moreover, the healthcare system was under immense pressure, with hospitals overwhelmed by patients suffering from heat-related conditions. This has made it difficult for those experiencing mental health crises to access the care they need.

Dr Kulkarni noted that with weather changes, the number of admissions to mental health facilities also increased. She said that awareness about mental health is crucial in addressing the increased demand for mental health issues as well.

"If primary healthcare professionals like physicians can identify that someone's mental health is under duress due to weather and maybe if need be, refer people to mental health professionals, it will help the public. Secondly, I feel that at the individual level as well, if parents are aware, they will be able to inculcate in their progeny," she said.

She added that people could also practice things like five minutes of mindfulness can assist in dealing with the mental impact of heatwaves. She also said that NGOs who work with persons from low-income backgrounds can also connect them with mental healthcare providers.

Dr Sonal, like Dr Kulkarni, recommended practicing mindfulness and also practicing breathing techniques to lower irritability; the professional working with Wockhardt Hospital said that practicing yoga can help in lowering irritability.

Echoing similar thoughts to those of Dr Kulkarni, Dr Ajinkya said identifying high-risk patients and developing personalised care plans, including medication reviews and regular check-ins, are critical steps in keeping those struggling mentally well during excessive heat.

He suggested accessing telehealth services and helplines that offer crisis intervention to ensure an individual receives mental health support.

The experts said educating patients about hydration, cooling measures, and medication modifications is critical, as is training healthcare personnel to recognise and respond to heat-related mental health disorders.

Dr Ajinkya said that at the community level, building well-publicised cooling stations and organising volunteer wellness checks can help vulnerable people.

Both Dr Ajinkya and Dr Kulkarni said that if the development of green spaces is promoted, it can also help mitigate the urban heat.