Lipids are essential for cell function and healthy metabolism however clinical analysis of a patient’s lipid profile also addresses one of the fundamental drivers of atherosclerotic cardiovascular disease responsible for 25 % of all deaths in Australia. Modification of abnormal serum lipid levels by lifestyle and pharmacologic intervention aims to achieve a healthy coronary circulation reducing new atheroma formation and stabilizing preexisting atheromatous plaques.

Heart disease affects one in six Australians with an AMI occurring every 10 minutes and accounts for one in four of all deaths, so primary and secondary prevention are very important considerations in relation to any patient presenting with heart disease or at risk of heart disease. Risk factors including family history, lipid abnormalities, diabetes mellitus, hypertension, smoking or those with elevated BMI all need consideration. Whilst there have been significant controversies regarding lipids management and the use of statins, the evidence for their use, particularly in secondary prevention of heart disease is clear.

Non-melanotic skin cancers and melanoma are the most common cancers affecting humans. At least two in three Australians will be diagnosed with skin cancer before the age of 70 years and the risk is higher for men than women. Whilst basal cell carcinomas and squamous cell carcinomas are more common they are not as lethal as melanomas which are referred to as Australia’s “national cancer”. Indeed in 2020 it is estimated that 16,200 will be diagnosed with melanoma, that is one new case every half hour and a death every five hours.

The western world faces a very significant obesity epidemic. In Australia, two-thirds of our population or 12.5 million are either overweight or obese and as a consequence may experience many medical sequelae including development of the metabolic syndrome, type 2 diabetes, cardiovascular disease, cerebrovascular disease, osteoarthritis and depression, contributing significantly to our health burden. In the first part of this series, we were joined by Joseph Proietto, Professor Emeritus at the University of Melbourne, the Department of Medicine at Austin Health and an endocrinologist specialising in diabetes and obesity to discuss why we become obese. Professor Proietto joins us again to guide us through a strategy of how to treat and manage obesity and direct our patients toward a healthy body mass index (BMI).

Up to two thirds of Australians are either overweight or obese as defined by body mass index (overweight: BMI 25-29.9, obese: BMI >30) with subsequent significant medical consequences including cardiovascular disease, type 2 diabetes, cerebrovascular disease (metabolic syndrome), osteoarthritis and depression. Becoming overweight and obese involves complex interactions between neurohormonal systems of the gut, neurobiology of the brain (particularly the hypothalamus) and leptin production from adipose sites coupled with an environment where there is an abundance of high glycaemic energy dense foods. Science demonstrates that the overarching controls of obesity are genetic (70%) rather than environmental (30%). Adoption studies relating to monozygotic twins demonstrate this. In view of the metabolic consequences of obesity, understanding why we get fat is extremely important to medical practitioners.

The spleen performs a large number of important functions including processing and removal of opsonized pathogens, cellular maintenance, immunoglobulin production and the removal of effete worn out red blood cell. When removed either through trauma or for therapeutic indications the risk of overwhelming post splenectomy infection (OPSI) increases significantly; up to 58 times the general population in the setting of trauma and up to 1,100 times increased risk when for thalassaemia.