Obesity is the accumulation of excessive body fat, and has become a significant problem in affluent and developing countries. The World Health Organisation (WHO) adopted the Body Mass Index (BMI) as a means of measuring the total body fat.
With this index, obesity is defined when the BMI is equal to or greater than 30kg/m^2. Besides the measure of the total body fat, the pattern of distribution is a considerable factor.
Central obesity is associated with cardiovascular diseases than subcutaneous fat which is deposited mainly around the hips and buttocks. This reflects in the Waist: Hip ratio (WHR) which is the ratio of the hip circumference to waist circumference.
Current Evidence linking Obesity and Mortality:
Studies such as the Framingham heart study and Fontaine et al found a reduction in life expectancy in the obese. Evidently, the percentage of fat assessed by the BMI and the distribution of fat in the body are used in predicting mortality.
High hip fat distribution assessed by hip circumference has a negative predictive effect on myocardial infarction unlike high waist fat distribution.
Morbidities related to Obesity:
A study found that overweight or obesity was the main predictor of type 2 Diabetes mellitus (DM).
The risk of developing DM is higher in those with BMI>23kg/m^2. In Malawi, the prevalence of DM in adults aged 25-64 years is estimated at 5.6%.
There is a strong association between obesity and hypertension. BMI is positively associated with hypertension at midlife as there is a risk of hypertension with weight gain.
It is also evidence that there is an increased risk of coronary artery disease in obesity. Heart failure was found to be 2-fold in the obese than in the non-obese. It also appears that having a higher BMI improves survival in patients with congestive heart failure.
In 1998, Gary et al explained the association between obesity and dyslipidaemia to be directly proportional, and appears to be the basis for the features seen in metabolic syndrome.
Obesity is linked to obstructive sleep apnea, increased neck circumference, and asthma.
Ischaemic and haemorrhagic stroke occurrence increases with obesity in men. In women, ischaemic stroke does increase but not haemorrhagic stroke. Recently, central obesity is considered important in predicting stroke mortality.
There is also an increased risk of gastroesophageal reflux disease, cholelithiasis (gallstones), esophageal cancer, and erosive esophagitis with obesity.
In men, central obesity is associated with impotence and infertility, while polycystic ovary syndrome, gestational diabetes, and macrosomia(large babies) are reproductive complications of obesity in women.
Obesity is implicated in osteoarthritis, cancer, psychosocial problems, and can prevent certain medical and surgical procedures.
Obesity and other risk factors of non-communicable diseases have become more challenging not only in affluent societies but in developing regions like Malawi. Clinicians are to look out for these complications in obese patients and emphasize the benefits of weight loss.
Written by Victor Maduwuba, 4th year medical student, Nigeria
Photo by Godaddy stock images
Segula D. (2014). Complications of obesity in adults: a short review of the literature. Malawi medical journal: The Journal of Medical Association of Malawi, 26(1), 20–24.