Читать книгу Urban Ecology and Global Climate Change - Группа авторов - Страница 54

It has been reported that overweight and obesity are the causes of more number of deaths worldwide than underweight. Studies investigating the cause for the increase in frequency of obesity have identified a strong correlation between obesity and urbanisation and also between obesity and physical activity and chronic diseases (Dey and Senapati 2021a). This is so because obesity facilitates the incidence of cardiometabolic syndromes including insulin resistance, dyslipidaemia, and hypertension which together leads to chronic CVD, stroke, some types of cancer, and type II diabetes (Table 2.1). According to WHO, obesity and life‐threatening excessive accumulation of BF is a major requisite risk factor and largest contributor in the aetiology of cardiometabolic syndrome and disorders.

The association of obesity and cardiometabolic syndrome is known to increase the risk of type 2 diabetes mellitus by fivefold and CVD by threefold. The impact of obesity‐linked cardiometabolic risk is so adverse that various present studies aim to establish more specific and optimal cut‐off values for anthropometric indicators of obesity to prevent the burden of healthcare on the economy (Figure 2.8) (Macek et al. 2020).

Figure 2.8 The most prevalent shared risk factors between obesity, cancer, and cardiometabolic syndrome. CMS, cardiometabolic syndrome.

Major obesity complications relate to the pathology of disrupted metabolic homeostasis regulated primarily by several adipokines and cytokines such as leptin, adiponectin, tumour‐necrosis‐factor (TNF)‐α, and interleukin (IL)‐6. Obesity complications disrupt the normal adipose physiology in both men and women differently. It causes non‐alcoholic fatty liver disease (NAFLD) which is the most common chronic liver disorder and many cardiometabolic disorders including high fasting triglycerides; low ‘good’ HDL cholesterol, high levels of C‐reactive protein in the blood, a marker of chronic inflammation and elevated blood pressure. The coexistence of two or more of the cardiometabolic syndromes facilitated by obesity doubles the risk of CVD and heart attack and stroke and increases the risk of diabetes fivefold in a period of 5–10 years (Virani et al. 2020).

The rise of progressive urbanisation and related globalisation of unhealthy, sedentary, and stressful lifestyles result in overweight, which has potential adverse health consequences such as CVD including CHD, atrial fibrillation, venous thromboembolism, and congestive heart failure. The urban setting and fast‐moving face of life in the cities have led to an increasing trend in fast food consumption and out‐of‐home eating lifestyle. It ultimately culminates in a lower diet quality with lower micronutrient balance, high calorie, and fat intake. These impair the fat metabolism, homeostasis of glucose and insulin, oxidative stress, sleep disorders, and lipid and lipoprotein disorders which are together also termed as cardiometabolic disorders (Bahadoran et al. 2016). The association of obesity and related cardiometabolic disorders was initially highly prevalent in the United States, Europe where the implementation of urbanisation and industrialisation first began. The trend of two‐ to threefold increase in the prevalence of overweight and obesity was reported in developing countries of the Middle East and southwest Asia between the late nineteenth century and continues till date. Incidence studies of CVD highlight that between the age of 20 and 79 years, overweight and obesity correlated with the early development of major cardiometabolic disorder stress followed by CVD and resulted in higher mortality with obesity. Half of the world's population with metabolic healthy obesity develop metabolic syndrome and poses increased threat of CVD compared with those with a healthy normal weight. Therefore, the presence of metabolically healthy obesity is also a high‐risk state rendering greater cardiovascular risk age, BMI, and obesity are also risk factors for stroke, venous thromboembolism risk, and hypertension in patients. Metabolic syndrome related to obesity is also linked to other issues caused by obesity which include sleep issues, obstructive sleep apnea, and breathing troubles including asthma (Drager et al. 2013). In this regard, the latest research is focused on the development of compositions and compounds which are cardio‐protective and anti‐cardiac in nature (Kundu et al. 2019a). Research in this area is a key to lower the burden of CVD in the society (Kundu et al. 2019b).