What Causes Diabetes Mellitus Write Its Symptoms

Diabetes mellitus is a chronic metabolic disorder that has reached epidemic proportions globally. It is characterized by elevated blood glucose levels, either due to insufficient insulin production by the pancreas (Type 1 diabetes) or the body’s ineffective use of insulin (Type 2 diabetes), along with gestational diabetes that occurs during pregnancy. The consequences of uncontrolled diabetes are far-reaching, affecting multiple organ systems and leading to serious complications such as cardiovascular disease, kidney failure, nerve damage, and vision impairment.

The importance of understanding the causes and symptoms of diabetes cannot be overstated. Early recognition of the symptoms can prompt timely medical intervention, which is vital for slowing down the progression of the disease and reducing the risk of associated complications. Moreover, awareness of the causative factors allows individuals to take preventive measures, especially those at high risk. With the rising prevalence of diabetes, it is essential for healthcare providers, patients, and the general public to have in-depth knowledge about this condition to better manage and combat it.

Types of Diabetes Mellitus

Type 1 Diabetes

Type 1 diabetes, formerly known as juvenile diabetes, typically emerges in childhood or adolescence, although it can occur at any age. It is an autoimmune disease where the body’s immune system mistakenly attacks and destroys the insulin-producing beta cells in the pancreas. The exact trigger for this autoimmune response remains unclear, but genetic and environmental factors are believed to play a role. Viral infections, such as enteroviruses, in genetically susceptible individuals may initiate the immune attack. Once these beta cells are damaged, the pancreas loses its ability to produce sufficient insulin, leading to hyperglycemia. Insulin injections are essential for survival in patients with Type 1 diabetes as their bodies can no longer make enough of this crucial hormone on their own.

Type 2 Diabetes

Type 2 diabetes is the most common form, accounting for around 90% of all diabetes cases. It often develops gradually over years, usually in adulthood, although an increasing number of adolescents and young adults are being diagnosed. In Type 2 diabetes, the body becomes resistant to the action of insulin, meaning that cells do not respond properly to insulin signals to take up glucose from the bloodstream. As a result, the pancreas tries to compensate by producing more insulin. However, over time, the pancreas may not be able to maintain this increased production, and blood glucose levels rise. Obesity, sedentary lifestyle, poor diet high in refined carbohydrates and saturated fats, and genetic factors are major contributors to the development of Type 2 diabetes.

Gestational Diabetes

Gestational diabetes occurs during pregnancy, usually in the second or third trimester. Hormonal changes during pregnancy, such as increased levels of placental hormones like human placental lactogen and progesterone, can interfere with the normal action of insulin, leading to insulin resistance. Most women with gestational diabetes return to normal blood glucose levels after childbirth. However, they are at a higher risk of developing Type 2 diabetes later in life, emphasizing the need for continued monitoring and lifestyle modifications.

Causes of Diabetes Mellitus

Genetic Factors

Genetics play a significant role in diabetes susceptibility. In Type 1 diabetes, multiple genes have been identified that are associated with an increased risk of developing the autoimmune attack on the pancreas. For example, certain variants in the HLA (human leukocyte antigen) genes are linked to a higher likelihood of Type 1 diabetes. In Type 2 diabetes, family history is a strong predictor. If a first-degree relative has Type 2 diabetes, an individual’s risk is substantially elevated. Genes related to insulin secretion, insulin action, and glucose metabolism are among those implicated, such as the TCF7L2 gene, mutations or variants of which are associated with impaired insulin secretion and increased risk of Type 2 diabetes.

Lifestyle Factors

Diet: A diet rich in processed foods, sugary beverages, and high-calorie, low-nutrient items contributes to weight gain and insulin resistance, a precursor to Type 2 diabetes. Consuming large amounts of refined carbohydrates leads to rapid spikes in blood sugar, overloading the body’s insulin response mechanism. For instance, regular intake of soda, which contains high amounts of added sugars, can disrupt normal glucose regulation over time.

Physical Inactivity: Sedentary lifestyles, with long hours of sitting at work or in front of screens, are linked to decreased muscle mass and reduced insulin sensitivity. When muscles are not regularly engaged in physical activity, they take up less glucose from the bloodstream, forcing the pancreas to work harder to maintain normal blood sugar levels. Lack of exercise also contributes to weight gain, further exacerbating the risk of diabetes.

Obesity: Excess body fat, especially abdominal fat, is a major risk factor for Type 2 diabetes. Adipose tissue releases hormones and cytokines that can interfere with insulin signaling and promote inflammation, leading to insulin resistance. As body mass index (BMI) increases above the normal range (18.5 – 24.9), the risk of developing diabetes rises exponentially.

Medical Conditions and Medications

Polycystic Ovary Syndrome (PCOS): Women with PCOS often have hormonal imbalances, including elevated levels of androgens. This condition is associated with insulin resistance, and many women with PCOS are at an increased risk of developing Type 2 diabetes. The underlying mechanisms involve disruptions in the normal signaling pathways related to insulin action and glucose metabolism within the ovaries and other tissues.

Cushing’s Syndrome: This endocrine disorder results from excessive production of cortisol, a stress hormone. High cortisol levels lead to increased blood sugar levels by promoting gluconeogenesis (the production of glucose from non-carbohydrate sources) in the liver and reducing the sensitivity of tissues to insulin. Over time, this can cause diabetes mellitus.

Certain Medications: Some drugs, such as steroids used for treating inflammatory conditions like asthma or rheumatoid arthritis, can disrupt glucose metabolism and increase the risk of diabetes. These medications may affect insulin secretion, insulin action, or both, leading to elevated blood glucose levels during their use and potentially triggering diabetes in susceptible individuals.

Symptoms of Diabetes Mellitus

Classic Symptoms

Polyuria: One of the hallmark symptoms of diabetes is increased urination. High blood glucose levels spill over into the urine, drawing water with it due to osmotic pressure. This leads to more frequent trips to the bathroom, sometimes disrupting sleep at night. For example, a person with uncontrolled diabetes may notice having to urinate every hour or two, compared to the normal frequency of several times a day.

Polydipsia: As a result of losing excess water through urine, patients experience intense thirst and drink large amounts of fluids to quench it. The body tries to compensate for the fluid loss caused by polyuria, leading to an unquenchable thirst. This can involve consuming several liters of water or other beverages daily, far more than the average person’s intake.

Polyphagia: Despite eating more than usual, individuals with diabetes may still feel hungry. The cells are not getting enough glucose due to insulin problems (either lack of insulin or resistance to it), so the body sends signals to the brain that it needs more food to obtain energy. This can lead to overeating and weight gain in some cases, especially in the early stages of Type 2 diabetes before significant metabolic derangements occur.

Other Common Symptoms

Fatigue: High blood sugar levels and the body’s inability to properly utilize glucose for energy production lead to feelings of tiredness and lack of energy. Cells are starved of the energy they need, even though there is an abundance of glucose in the bloodstream. This fatigue can be persistent, affecting daily activities and productivity, making it difficult for patients to perform routine tasks without feeling exhausted.

Blurred Vision: Fluctuating blood sugar levels can cause changes in the shape of the lens in the eye, leading to blurred vision. In the short term, this may be reversible once blood sugar is controlled, but chronic hyperglycemia can damage the blood vessels in the retina over time, resulting in diabetic retinopathy, a serious eye condition that can lead to vision loss if untreated.

Slow Wound Healing: Diabetes affects the body’s microcirculation and immune function. Poor blood flow to the extremities and reduced ability of the immune system to fight infections mean that cuts, bruises, and other wounds take longer to heal. Even minor injuries like a small cut on the foot can become chronic ulcers, which are at high risk of infection and can lead to more severe complications such as amputation in severe cases.

Less Obvious Symptoms

Tingling or Numbness in Extremities: Diabetic neuropathy, nerve damage caused by prolonged high blood sugar, often presents as a tingling or numb sensation in the hands and feet. This occurs as the nerves are damaged by hyperglycemia-induced oxidative stress and impaired blood supply. Initially, it may be mild, like a pins-and-needles feeling, but can progress to more severe pain and loss of sensation, increasing the risk of accidental injuries as patients may not be aware of pressure or injury to the affected areas.

Recurrent Infections: High blood sugar provides a fertile environment for bacteria and fungi to thrive. Women may experience frequent urinary tract infections or vaginal yeast infections, while both men and women are at an increased risk of skin infections. These infections tend to recur more often than in those without diabetes and may be more difficult to treat due to the underlying metabolic abnormalities and compromised immune function.

Dry Skin and Itching: Diabetes can cause dryness and itching of the skin, especially on the legs and feet. The combination of poor circulation and nerve damage can disrupt the normal function of the skin’s sweat glands and sensory nerves, leading to dry, itchy skin. Scratching to relieve the itch can further damage the skin, increasing the risk of infections.

Diagnosis and Monitoring

Accurate diagnosis of diabetes mellitus involves several tests. The most common is the fasting plasma glucose test, where blood is drawn after an overnight fast. A level of 126 mg/dL or higher on two separate occasions indicates diabetes. The oral glucose tolerance test is used, especially for diagnosing gestational diabetes, where the patient drinks a glucose solution and blood sugar levels are measured at intervals. Another key test is the measurement of HbA1c (glycated hemoglobin), which reflects average blood sugar levels over the past 2 – 3 months. An HbA1c level of 6.5% or higher is diagnostic of diabetes.

Once diagnosed, regular monitoring of blood sugar levels is crucial. Patients with Type 1 diabetes often check their blood glucose multiple times a day using a glucometer to adjust insulin doses. Those with Type 2 diabetes may monitor less frequently, depending on the severity of their condition and treatment plan. Additionally, routine check-ups for kidney function (through tests like creatinine and urine albumin), eye examinations for retinopathy, and nerve function tests to detect neuropathy are essential to catch and manage potential complications early.

Conclusion