Conditions That Are Associated With Obesity
Obesity as a condition has been recognized since ancient times, with Hippocrates noting that obesity is not merely a disease but also a precursor to other health conditions.Multiple organ systems can be involved in obesity associated conditions and the list is exhaustive.
What has lead to the obesity crisis in India?
Cardiovascular System
- Hypertension: There is a linear association of hypertension with increasing BMI. Hypertension can be ascribed to weight gain in 78% of men and 65% in women.
- Coronary artery disease( CAD): This condition is typically associated with diabetes, hypertension, dyslipidemia, and obstructive sleep apnea (OSA), which frequently accompany obesity. CAD encompasses events such as stable and unstable angina, myocardial infarction with resulting heart failure and arrhythmias, and sudden cardiac death.
- Heart failure: Obesity has been directly correlated with congestive heart failure with preserved ejection fraction (HFpEF). This is a specific subtype of heart failure where the left ventricle is unable to fill adequately but can pump out blood normally or near normally.
- Atrial fibrillation: Atrial fibrillation is the most common rhythm disturbance of the heart that is associated with heart failure, strokes, and life-threatening infarctions elsewhere in the body. There is a 5% increase in the risk of developing atrial fibrillation for each unit increase in BMI, particularly more than 30 kg/m2
- Stroke: An increased risk of stroke exists with increasing BMI, including early-onset ischemic stroke.
- Venous thromboembolism: Patients with obesity may have reduced mobility and also a tendency towards blood clotting which can lead to increased risk of blood clotting in the lower limb veins.Clotted blood in the lower limb veins can get detached and travel to the lungs and cause life threatening respiratory compromise.
Respiratory System
- Obstructive sleep apnea: OSA involves complete airway obstruction during sleep despite normal breathing efforts. This has widespread negative cardiovascular and metabolic effects for eg.insulin resistance, dyslipidemia, hypertension, and CAD.
- Obesity hypoventilation syndrome: Also called as Pickwickian syndrome it is characterized by an inability to breathe rapidly or deeply enough thereby retaining excessive carbon dioxide in the body.
Metabolic/ Endocrine disoders
- Type 2 diabetes: Type 2 diabetes is a well-established association and complication of obesity, with around 80% of patients with type 2 diabetes being obese. Diabetes is an independent risk factor for coronary artery disease.
- Dyslipidemia: Up to 70% of patients with obesity have comorbid dyslipidemia, which is seen as elevated low-density lipoproteins (LDL) and reduced levels of high-density lipoproteins (HDL).
- Metabolic syndrome: This constellation of clinical features includes truncal obesity, dyslipidemia, hypertension, and abnormal fasting glucose levels in the blood. This syndrome is a precursor for a number of metabolic disorders.
Nervous System
- Idiopathic intracranial hypertension: This condition is characterized by raised intracranial pressure, which manifests with headaches, nausea, vomiting, and visual changes such as blurring or double vision. The increased intracranial pressure results in pressure on the optic nerve and if sustained may result in vision loss. 90% of these cases occur in those who are obese.
- Stroke: Being overweight increases the risk of stroke by 22% and in the case of obesity that risk increases by 64%. The devastating consequences of stroke are well known in the general population.
Cardiovascular System
- Hypertension:There is a linear association of hypertension with increasing BMI.Hypertension can be ascribed to weight gain in 78% of men and 65% in women .
- Coronary artery disease( CAD):This condition is typically associated with diabetes, hypertension, dyslipidemia, and obstructive sleep apnea (OSA), which frequently accompany obesity. CAD encompasses events such as stable and unstable angina, myocardial infarction with resulting heart failure and arrhythmias , and sudden cardiac death.
- Heart failure: Obesity has been directly correlated with congestive heart failure with preserved ejection fraction (HFpEF). This is a specific subtype of heart failure where the left ventricle is unable to fill adequately but is able to pump out blood normally or near normally.
- Atrial fibrillation: Atrial fibrillation is the most common rhythm disturbance of the heart that is associated with heart failure, strokes and life-threatening infarctions elsewhere in the body.There is a 5% increase in the risk of developing atrial fibrillation for each unit increase in BMI, particularly more than 30 kg/m2
- Stroke: An increased risk of stroke exists with increasing BMI, including early-onset ischemic stroke.
- Venous thromboembolism: Patients with obesity may have reduced mobility and also a tendency towards blood clotting which can lead to increased risk of blood clotting in the lower limb veins.Clotted blood in the lower limb veins can get detached and travel to the lungs and cause life threatening respiratory compromise.
Musculoskeltal system
- Osteoarthritis: The increased weight on the joints results in greater compressive forces and altered biomechanics. The knee is the most commonly affected joint being a weight-bearing joint. Surgical management of this is also associated with an increased risk for complications, including prolonged hospital stays, infection, and the necessity for further surgery.
- Patients with obesity are more prone to experiencing falls and fractures seen in both children and adults.
- In children with obesity Additionally, conditions such as slipped upper femoral epiphyses ( a hip condition in that occurs when the top of the thighbone slips out of place) , genu varus (bow legs)and genu valgus ( knock knees ) are commonly seen.
Cardiovascular System
- MASLD (Metabolic Dysfunction-Associated Steatotic Liver Disease) previously known as Non-alcoholic fatty liver disease(NAFLD) It is a chronic liver disease that affects more than 30% of the global population. It can be asymptomatic but can lead to inflammation, scarring, liver cancer, or the need for a liver transplant. People with diabetes, obesity, high blood pressure, and high cholesterol are at higher risk.
- Gallstones: The positive correlation between increasing BMI and the development of gallstones is well-recognized. The risk increases even within the healthy weight range, indicating a strong link between weight gain and gallstones.
- Gastroesophageal reflux disease: GERD is attributed to patients with obesity among other causes. As a result of acid reflux, patients with obesity are more likely to experience erosions, strictures, and pre-cancerous transformations, such as Barrett esophagus, as well as esophageal adenocarcinoma.
Kidney and Urinary Tract
The development of chronic kidney disease (CKD) is observed in patients with obesity, although the mechanism and risk factors remain contentious.
Reproductive System
Obesity can affect the reproductive function of a woman by one or more mechanisms such as impairment of ovulation, impairing the endometrium’s ability to receive an embryo, altered estrogen levels, creating an inflammatory state in the body, etc.
These disruptions can manifest as:
- Irregular menstrual cycles
- Polycystic ovary syndrome (PCOS) which is characterized by hyperandrogenism, irregular periods, and polycystic ovaries.
- Infertility
Sexual dysfunction: Obesity is also associated with sexual dysfunction in both women and men. Women with obesity often experience higher sexual dysfunction scores. In men, obesity is an independent risk factor for developing erectile dysfunction, with 80% of those experiencing erectile issues having a BMI of 25 or greater
Psychiatric Disorders
The incidence of depression is higher in patients with obesity, especially among young women. Additionally, an association between obesity and dementia has been observed; however, the mechanism remains poorly understood, and whether obesity constitutes an independent risk factor for dementia is uncertain.
Skin and soft tissues
Obesity affects the skin in several ways by reducing skin hydration, decreasing collagen deposition relative to skin surface area, increasing sebum and sweat production, and altering circulation and lymphatics. Moreover, obesity increases the risk of infections, delays wound healing and promotes the development of pressure sores. Additionally, elevated androgens and insulin resistance contribute to conditions such as hirsutism (excessive facial hair in a woman) and acanthosis nigricans (dark, velvety patches in body folds and creases)
Infections
Obesity is associated with higher rates of bacterial infections, post-surgical infections, and increased mortality from flu and COVID-19. Patients with obesity often require higher than typical doses of medications, which can lead to adverse outcomes
Neoplasms/ Cancer
The risk of cancer is higher among women with obesity compared to men, and obesity increases the likelihood of cancer-related mortality.
Several well-associated cancers include:
- Esophageal adenocarcinoma
- Gastric cancer
- Colorectal cancer
- Hepatocellular carcinoma
- Cholangiocarcinoma
- Pancreatic cancer
- Endometrial carcinoma
- Ovarian cancer
- Breast cancer
- Renal cell carcinoma
