Anorexia Nervosa and Its Impact on Kidneys

Introduction

Anorexia nervosa refers to an eating disorder that affects kidneys in various ways. Anorexia nervosa is associated with various conditions like dysfunctions of the renal, metabolic, endocrine, and gastrointestinal systems. Anorexia nervosa causes various disorders like kidney disorders, mineral disorders, and physical disorders. Kidney disease may progress to renal failure. Kidney disease is the most common complication of anorexia nervosa.

What Is Anorexia Nervosa?

Anorexia nervosa is a psychiatric disorder characterized by restricted food intake. It is an eating disorder in which the individual has low body weight due to restricted food intake. An individual with this disorder has an overpowering desire to remain thin. It is a psychiatric disorder because individuals imagine themselves as overweight despite their low body weight. The term anorexia refers to loss of appetite, and nervosa refers to the functional and non-organic nature of this disorder.

Individuals with this disorder deny that they are underweight. They frequently weigh, eat small amounts of food, and eat only certain foods. Some exercise, induce vomiting, or use laxatives to maintain low weight and control body shape. The reason for this disorder remains unknown but may be associated with psychological, sociocultural, and developmental risk factors.

What Are the Signs and Symptoms Associated With Anorexia Nervosa?

Anorexia nervosa is associated with signs and symptoms that exhibit starvation. The signs and symptoms may be physical, affective, cognitive, behavioral, and perceptual. The signs and symptoms include the following:

Physical Symptoms

• Low body mass index.

• Amenorrhea occurs due to prolonged weight loss.

• Fear of weight gain.

• Hair thinning, dry hair, and skin.

• Rapid and continuous weight loss.

• Bradycardia (slow heart rate) or tachycardia (increased heart rate).

• Chronic fatigue.

• Carotenosis (orange discoloration of the skin).

• Infertility.

• Halitosis (bad breath).

• Hypotension or orthostatic hypotension.

• Muscle tension, aches, and pain.

• Insomnia.

• Abdominal distension.

Cognitive Symptoms

• Obsession with calories and amount of food.

• Admiring thinner people.

• Preoccupation with food, calories, or cooking.

• Depression.

• Thoughts of being fat.

• Impaired theory of mind.

• Difficulty in thinking and problem-solving.

• Inflexible thinking.

• Poor self-esteem.

• Hypercriticism and perfectionism.

Affective Symptoms

• Depression.

• Ashamed of one’s own body.

• Anxiety disorders.

• Rapid mood swings.

• Emotional dysregulation.

• Alexithymia (difficulty in identifying emotions).

Behavioral Symptoms

• Food or energy restrictions despite the underweight or a healthy weight.

• Food rituals like refusing to eat food and cutting food into tiny pieces.

• Purging with laxatives, ipecac syrup, diet pills, or diuretics.

• Excessive exercise, micro exercises like persistent movements for smaller fingers or toes.

• Self-harming or self-loathing.

• Avoiding friends and family and becoming withdrawn and secretive.

Perceptual Symptoms

• Perception of overweight, despite the underweight.

• Intolerance to cold and the persistent feeling of being cold.

• Altered representation of the body.

• Altered interoception.

Anorexia nervosa is associated with comorbidities like obsessive-compulsive disorder (OCD), obsessive-compulsive personality disorder (OCPD), depression, alcoholism, anxiety disorders, attention deficit hyperactivity disorder (ADHD), and body dysmorphic disorder. Depression is the common comorbidity of anorexia nervosa, resulting in the worst outcome.

What Are the Complications Associated With Anorexia Nervosa?

Anorexia nervosa is an eating disorder marked by self-starvation, weight loss, and malnutrition. As the illness progresses, various complications develop.

• Kidney diseases are the common complications associated with anorexia nervosa. It causes electrolyte abnormalities.

• It causes cardiac problems that result in changes in the functioning of the heart. Complications like myocardial atrophy, mitral valve prolapse, and pericardial effusion may develop due to progressive weight loss. Sinus bradycardia, reversible sinus node dysfunction, and orthostatic hypotension are also observed in anorexia nervosa.

• As a result of progressive weight loss, gastrointestinal complications like gastroparesis and constipation can occur. Superior mesenteric artery syndrome (a gastrovascular disorder) may occur due to weight loss-induced mesenteric pad of fat atrophy. Diarrhea occurs due to small-bowel atrophy. Liver diseases and functional bowel disorders are also common.

• Pulmonary complications occur due to the weakening of the pharyngeal muscles. Complications like spontaneous pneumothorax, pneumomediastinum, and aspiration pneumonia are observed.

• Malnutrition causes leukopenia and anemia.

• Endocrine abnormalities like amenorrhea, low leptin levels, and hypoglycemia can occur.

• Bone loss, muscle loss, and brain atrophy are common complications of anorexia nervosa.

• Dermatological complications like xerosis, dry and fissured skin, acrocyanosis, and lanugo hair are observed.

How Does Anorexia Nervosa Cause Kidney Disease?

Anorexia nervosa causes kidney disease, including electrolyte abnormalities. Anorexia nervosa is characterized by starvation which leads to hypokalemia. Hypokalemia may be caused by deficient potassium intake, habitual vomiting, or abuse of diuretics or laxatives. Starvation causes a decrease in insulin levels and an increase in glucagon levels. Insulin promotes potassium transport from the extracellular compartment to the intracellular compartment, lowering serum potassium levels. This mechanism provides energy to the starving cells. Hypokalemia induces various changes in kidney function and impairs tubular transport, resulting in tubulointerstitial diseases and cyst formation. Renal calcifications, chronic dehydration, and rhabdomyolysis are also due to hypokalemia.

Chronic hypokalemia causes renal ischemia, tubulointerstitial damage, renal tubular fibrosis, cyst formation, and atrophy. Renal ischemia causes glomerular shrinkage and collapse. Kidney ischemia causes chronic kidney injury, irreversible fibrosis, and sclerosis in the kidneys. It may progress to renal failure and even end-stage renal disease.

How Is Anorexia Nervosa-Induced Kidney Disease Managed?

The treatment methods to manage anorexia nervosa and kidney disease are complex. Anorexia nervosa is managed with psychotherapy, nutrition counseling, medication, group or family therapy, and hospitalization.

• Psychotherapy is a type of counseling that is given to change the thinking and behavior of the individual.

• Cognitive behavioral therapy and nutrition counseling help in improving eating behavior.

• Medications such as Olanzapine can help in weight gain.

• Anorexia nervosa-induced kidney diseases require dialysis for maintenance therapy. Cessation of purging and volume depletion are managed to treat kidney diseases.

• Hydration with oral or intravenous saline infusions helps in treating volume depletion.

• Dialysis is done to balance electrolytes and fluid levels and remove toxins.

• A renal transplant is required in end-stage kidney diseases.

Conclusion

Anorexia nervosa is a psychiatric disorder that causes complications throughout the body due to starvation and malnutrition. Renal complications are common in anorexia nervosa, and dialysis is performed as maintenance therapy to maintain kidney function. A complex treatment approach is required to manage anorexia nervosa, renal complications, and other complications. Early intervention is required to prevent anorexia nervosa and the worsening of the complications. A psychological approach is essential to help the individual overcome mental illness.