What is type 1 diabetes?
Type 1 diabetes (T1D) is a chronic autoimmune disease in which the body's immune system mistakenly attacks and destroys the beta cells of the pancreas. These cells are responsible for producing insulin, a hormone needed for cells to absorb glucose and maintain normal blood sugar levels [1]. As a result of this destruction, known as insulitis, the body loses the ability to produce insulin, leading to elevated blood glucose levels [1].
The development of T1D is associated with genetic predisposition. Specific genes, including major histocompatibility complex (MHC) genes and non-MHC genes, play a key role in disease susceptibility [3, 6]. In particular, HLA class II molecules are major determinants of predisposition or protection [3]. Beta-cell antibodies can appear as early as the first year of life, signaling the onset of the autoimmune process [3]. Among known environmental factors capable of triggering the development of T1D, only congenital rubella is clearly associated [3].
Main symptoms of type 1 diabetes
Symptoms of T1D often develop rapidly and can be quite pronounced. They are caused by the body's inability to use glucose as an energy source due to insulin deficiency. Classic signs include:
- Polyuria: frequent and excessive urination, as the kidneys attempt to flush excess glucose out of the body.
- Polydipsia: extreme thirst caused by fluid loss from frequent urination.
- Polyphagia: increased appetite despite weight loss, as cells do not receive energy from glucose.
- Unexplained weight loss: the body begins breaking down fats and muscle for energy.
- Fatigue and weakness: due to a lack of energy in the cells.
- Blurred vision: high blood sugar levels can affect the lens of the eye.
The role of insulin in T1D treatment
Because the pancreas completely or almost completely stops producing insulin in type 1 diabetes, insulin replacement therapy is vital [1]. Insulin is administered externally (usually through injections or an insulin pump) to keep blood glucose levels within the normal range. This helps prevent acute complications, such as diabetic ketoacidosis, and reduces the risk of long-term complications, including damage to the kidneys, nerves, eyes, and cardiovascular system.
Autoimmune comorbidities associated with T1D
Type 1 diabetes is often accompanied by other autoimmune diseases, known as autoimmune polyglandular syndrome. Up to one-third of patients with T1D may face this condition [1]. Early detection of antibodies to these diseases and latent organ dysfunction is critical for timely intervention and prevention of full-scale illness [1].
The most common associated autoimmune pathologies include:
- Autoimmune thyroid diseases: From 15% to 30% of patients with T1D suffer from autoimmune Hashimoto's thyroiditis or Graves' disease [1]. In children and adolescents, this rate is 14–28% for Hashimoto's thyroiditis and 0.5–7% for Graves' disease [5]. These conditions can affect glycemic control, leading to inadequate blood sugar control (average glycated hemoglobin increase up to 7.9–9.2%) and an increased number of hypoglycemia episodes in subclinical hypothyroidism [5]. Screening for autoimmune thyroid diseases is recommended in T1D [8].
- Autoimmune gastritis and/or pernicious anemia: Diagnosed in 5-10% of patients [1].
- Celiac disease: Occurs in 4-9% of patients [1].
- Addison's disease: A rare but serious condition affecting the adrenal glands, occurring in 0.5% of patients [1].
- Vitiligo: A skin pigmentation disorder observed in 2-10% of patients [1].
These conditions are characterized by the presence of specific autoantibodies, such as anti-thyroperoxidase in Hashimoto's thyroiditis or anti-tissue transglutaminase in celiac disease [1].
Psychological aspects of living with T1D
Living with type 1 diabetes can be challenging not only physically but also psychologically. Studies show a high prevalence of depression and anxiety symptoms among children and adolescents with T1D. The combined prevalence of depressive symptoms is about 30.04% [2]. The level of these symptoms correlates with glycemic control and diabetes management [2]. The interplay between psychosocial factors and T1D is complex, so screening for psychosocial risk factors is recommended from the time of diagnosis [2].
Conclusion
Type 1 diabetes is a serious autoimmune disease that requires ongoing medical supervision and lifelong insulin therapy. Understanding its symptoms, genetic and environmental factors, as well as awareness of associated autoimmune diseases and psychological aspects, play a key role in effectively managing the condition. A comprehensive approach, including regular monitoring, timely diagnosis of comorbidities, and psychological support, helps improve patients' quality of life and prevent complications.
Sources
- Type 1 diabetes and autoimmune polyglandular syndrome: a clinical review. (Type 1 diabetes and autoimmune polyglandular syndrome: a clinical review.)
- Symptoms of depression and anxiety in youth with type 1 diabetes: A systematic review and meta-analysis. (Symptoms of depression and anxiety in youth with type 1 diabetes: A systematic review and meta-analysis.)
- Type 1A diabetes induced by infection and immunization. (Type 1A diabetes induced by infection and immunization.)
- Thyroid diseases - ally or enemy of type 1 diabetes in children and adolescents? (Thyroid diseases – ally or enemy of type 1 diabetes in children and adolescents?)
- Genetics of type 1 diabetes: similarities and differences between Asian and Caucasian populations. (Genetics of type 1 diabetes: similarities and differences between Asian and Caucasian populations.)
- Thyroid autoimmunity in Type 1 diabetes: systematic review and meta-analysis. (Thyroid autoimmunity in Type 1 diabetes: systematic review and meta-analysis.)
The information provided in this article is for reference purposes only and should not be used for self-diagnosis or self-treatment. Always consult a qualified healthcare professional for an accurate diagnosis and individualized treatment plan.