Prevention of the perfect storm through lifestyle medicine |

Lifestyle medicine, the medical approach that uses evidence-based behavioural interventions to prevent, treat and manage chronic diseases, may be the best prevention against severe outcomes of COVID-19 and other diseases, says an expert.

Speaking at the recent 10^th Malaysian Hybrid Conference on Healthy Ageing 2022, Dr Sivaneswaran Poobalasingam, founder and president of the Malaysian Society of Lifestyle Medicine (MSLM), said the presence of noncommunicable diseases (NCDs) such as hypertension, diabetes and obesity led to poorer outcomes in COVID-19 patients. Compared to patients without any comorbidities, patients with diabetes had a two-fold increased risk of severe disease and three-fold increased risk for mortality upon hospitalization. [Prim Care Diabetes 2020;14:558–563] Similarly, those who were obese were more likely to contract COVID-19, and once infected, more likely to be hospitalized, and subsequently more likely to have severe disease. [Obes Rev 2020;21:e13128]

One of the ways to maintain a good immune system is by having a healthy balance of gut microflora, said Sivaneswaran. He said this balance is necessary to preserve the immune function of one’s body. He added that most lifestyle diseases can be prevented, managed, and even reversed. One of the ways to achieve this is through lifestyle medicine. “Lifestyle medicine is an evidence-based approach to preventing, treating, and even reversing diseases by replacing unhealthy behaviours with positive ones; for example, eating healthfully, being physically active, managing stress levels, avoiding risky substance abuse, adequate sleep and having a strong support system.”

Healthy eating	Focus on the regular consumption of vegetables and fruits. A Mediterranean-type diet reduces the risk of chronic diseases and increases immune function. These diets contain foods that are high in fibre and antioxidants and are anti-inflammatory in nature.
Regular exercise	Regular exercise that can be maintained on a daily basis such as walking, gardening and bodyweight exercises can reduce inflammation, improve immune function and decrease the risk and severity of respiratory infection. [Exerc Sport Sci Rev 2009;37(4):157–164]
Managing stress levels	Stress activates neuroendocrine and sympathetic pathways via the hypothalamus-pituitary adrenal axis and medullary adrenal sympathetic system. The end result of stress is the production of cortisol, adrenaline and noradrenaline. At the same time, the parasympathetic nervous system is inhibited. Stress decreases serotonin, dopamine, and gamma-aminobutyric acid (GABA) secretion by the body. Stress also induces gut dysbiosis and increases oxidative stress and inflammation. This cascades into impaired immune function, abdominal obesity, insulin resistance and abnormal lipid levels. Practising mindfulness is an effective way to manage stress. Mindfulness is the psychological process of bringing one’s attention to the internal and external experience occurring in the present moment which can be developed through the practice of yoga or meditation, among others.
Sufficient sleep	People who do not get enough quality sleep are more likely to fall sick after exposure to a virus. Lack of sleep will also affect the speed of recovery from an illness, and is linked closely to chronic stress and a predisposition towards metabolic disorders.
Social connectivity/Strong support network	Having a strong social connection with friends and family is linked to improved longevity and physiological parameters such as heart rate. This is due to the activation of the parasympathetic nervous system. [Available at https://news.harvard.edu/gazette/story/2017/04/over-nearly-80-years-harvard-study-has-been-showing-how-to-live-a-healthy-and-happy-life/ Accessed on 13 April 2022]
Prevention or cessation of substance abuse	Addictive substance use can increase the risk for many cancers and heart disease. Positive behaviours that improve health must include cessation of tobacco use and limiting the intake of alcohol.

What is the perfect storm?
Sivaneswaran said the immune system is made up of two components, the innate immunity and the adaptive immunity. “Now, when we have a dysfunctional immune response, what happens is that the innate immunity, the component that comes into play when a person is exposed to an infection, is unable to inhibit viral replication and eliminate infected cells. This can lead to an accelerated inflammatory response, which may lead to a cytokine storm.

He added when a person with a pre-existing NCD develops COVID-19, it can set the stage for what is known as the “perfect storm.” An uncontrolled COVID-19 infection can trigger a cytokine storm, which is the overproduction of pro-inflammatory cytokines and chemokines. These include tumour necrosis factor-α, interleukin (IL)-1β and IL-6. Consequentially, these molecules wreak havoc on the body and cause multiorgan damage, plus coagulation abnormalities that may lead to thromboembolic events and even death.

The evidence for lifestyle medicine
Sivaneswaran alluded to the situation in Okinawa, Japan, where its population consumed a predominantly plant-based diet with over half their daily caloric intake coming from sweet potatoes. They were also physically active, socially well-connected and had low levels of stress. As a result, they have long life expectancy and low mortality from cardiovascular diseases and certain types of cancers. Even during the COVID-19 pandemic, their death rate was 0.08 percent, which is one-sixteenth that of Tokyo at 1.3 percent. [Available at https://doi.org/10.1038/s41430-022-01082-w Accessed on 13 April 2022]

Further evidence supporting lifestyle medicine can be seen from a study of almost 200 patients with established cardiovascular disease (CVD) who were interested in transitioning to plant-based nutrition as an adjunct to usual cardiovascular care. At the end of a 4-year follow up, major cardiac events judged to be recurrent disease totalled only one stroke in the adherent cardiovascular participants—a recurrent event rate of .6%, while thirteen of 21 (62%) non-adherent participants experienced adverse events. . [J Fam Pract 2014;63(7):356–364b]

In closing, Sivaneswaran said the current global response to COVID-19 has been to treat it as a vertical disease rather than addressing its interaction with NCD and poverty. Given the interaction between COVID-19 and NCD, he said it was imperative to address the underlying drivers of the NCD pandemic that are fuelling COVID-19 mortality. Lifestyle medicine is one such intervention that will help to address the drivers of the NCD pandemic and help to enhance immune function, which in turn will attenuate the effects of the COVID-19 and future pandemics.