TO say COVID-19 has turned every country on its head, causing unprecedented public health, economic and societal pressure, is a colossal understatement. With no known therapies or preventive vaccine, the novel SARS-CoV-2 strain is responsible globally to date for over 450 000 deaths, more than 8 million infections and a global economic and social shutdown.
The development of a safe and effective vaccine against SARS-CoV-2, while being undertaken at breakneck speed, remains elusive.
The lack of an effective preventive vaccine highlights the importance of understanding what modifiable lifestyle factors predispose an individual to the development of severe COVID-19, including the requirement for mechanical ventilation and death. Recent analyses of adults under the age of 60 years hospitalised with COVID-19 in the US, France and many other countries clearly indicate individuals with severe obesity with a BMI over 35kg/m2 have a significantly greater risk (over 7 times that of individuals with a BMI less than 25kg/m2) of needing mechanical ventilation, with almost 50% of hospitalised patients with COVID-19 having obesity (here, and here). In a recent study in the US of patients with COVID-19 that required ICU admission, obesity was a significant clinical factor associated with severe COVID-19 in younger individuals (under 40 years of age). Moreover, it appears men are more susceptible to severe COVID-19 than women. Whether this gender difference is due to genetic, hormonal or behavioural factors remains unclear.
The many known underlying pathological effects of obesity may increase the risk of developing severe COVID-19. These include effects on the cardiorespiratory and immune systems and appear independent of the adverse effects of diabetes. Of relevance to COVID-19 are the effects of obesity on:
- development of a pro-inflammatory state;
- reduced respiratory reserve, including central and peripheral obstructive sleep apnoea and obesity-related hypoventilation syndrome;
- impairment of immune function secondary to nutritional micro- and macronutrient deficiencies and imbalances; and
- lack of adequate physical activity and sleep (here, and here).
In keeping with potential nutritional deficits and imbalances in individuals with obesity, a recent intriguing report suggested that vitamin D deficiency may be a possible modifiable risk factor and that vitamin D supplementation may prevent or ameliorate severe COVID-19, although the authors’ conflict of interest statement should be noted. This report is consistent with the known role of vitamin D as an anti-inflammatory agent. It also emphasises the importance of families in experiencing more outdoor activities together in natural settings; adequate and safe sunshine exposure through the effects of UV B light exposure on vitamin D pre-hormones in the skin may be the easiest and most reliable source of vitamin D for children and adults alike, depending on season, latitude and skin pigmentation.
Recent alarming reports have appeared of younger individuals (under 50 years of age) being severely affected by COVID-19-induced thrombotic strokes and COVID-19 affecting young children with a Kawasaki-like pro-inflammatory illness called paediatric multisystem inflammatory syndrome (PMIS). The influences of modifiable lifestyle factors on these rare non-respiratory manifestations of severe COVID-19 remain to be determined.
The obesity and COVID-19 link is troubling given that up to two-thirds of the adult population and a quarter to a third of children and adolescents fall into the overweight or obese range. Obesity also disproportionately affects many families from ethnic minorities and socially disadvantaged communities, who are generally ill-equipped to deal with the health and economic challenges of severe obesity, let alone COVID-19. This is a particularly highlighted in the US where the African-American population is disproportionately affected by COVID-19 (here, and here). Because the COVID-19 caseload in Australia has been small by comparison to the US and Europe, this ethnic and social disparity in COVID-19 infection, morbidity and mortality in Australia has not been apparent. This does not preclude all Australian families at high risk of obesity and diabetes, from all our nation’s many diverse ethnic backgrounds, to prioritise their family’s health and well-being.
In response to the need for improving safe opportunities for physical activity during the COVID-19 pandemic, the UK government recently announced 2 billion pounds of funding for expanding cycling and walking infrastructure. Anectodally, more urban Australian families during the COVID-19 pandemic appear motivated to cycle and walk. Initiated by Dr Ben Beck from the School of Public Health at Monash University, several medical, public health and transport researchers and relevant health organisations have written to the federal and all state governments in Australia calling for them to urgently expand funding for walking and cycling infrastructure for improved mental and physical health and wellbeing for all Australians. The recent appearance of pop-up cycle paths in several Australian cities has heeded this call for safer cycling opportunities.
As practising paediatric and adult endocrinologists dealing on a daily basis with children and their families with severe to extreme obesity, it seems apparent and urgent to us that the next 12-24 months represent a golden opportunity for starting a nation-wide public health campaign to improve family nutrition, physical activity and mindful living.
Such a campaign would help motivate families to make whole of family lifestyle changes so children, parents and grandparents alike can move to a healthier weight and live a more active purposeful life with improved social connection. Such family lifestyle changes are likely to also have a major positive impact on improving mental health, which is a major barrier to personal and family healthy behavioural change.
The motivation to make change in a family often falls on the mother, but in light of an increased risk of severe COVID-19 in males, it underscores the imperative that adult males within a family start taking greater responsibility to support their partner’s efforts for healthy family change and social connection. Improved strategies for supporting males of all ages to improve their self-care and thus support their family’s health are required. Greater public attention and support for this important public health priority is growing through organisations such as Beyond Blue, R U OK?, the Banksia Project and Spanner in the Works (delivered by the Australian Men’s Shed Association and Healthy Male).
We call upon all individuals and especially parents, with the support of your health professional team, to take on this 2020 Family Health Challenge. Then all Australian families can start a more positive family life journey together for a healthier weight, better mental and physical wellbeing, and better health and connection to their community, while also reducing their risk of severe COVID-19.
Associate Professor Gary Leong is Senior Staff Specialist in paediatric endocrinology and diabetes at the Nepean Blue Mountains Family Metabolic Health and Paediatric Diabetes Services, Nepean Hospital and the Nepean Charles Perkins Centre Research Hub. He writes under the pseudonym Dr Koala.
Dr Kathryn Williams is a Conjoint Senior Lecturer at the University of Sydney and the Clinical Lead and Manager for the Nepean Family Metabolic Health Service, a tertiary, public, whole of lifespan obesity service in the Nepean-Blue Mountains Local Health District. She is a staff specialist in endocrinology at Nepean Hospital.
The statements or opinions expressed in this article reflect the views of the authors and do not represent the official policy of the AMA, the MJA or InSight+ unless so stated.