Lesson Notes By Weeks and Term v3 - Senior Secondary 2
Non- Communicable Diseases
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Non- Communicable Diseases
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Subject: Health Education
Class: Senior Secondary 2
Term: 1st Term
Week: 7
Theme: Communicable And Non- Communicable Diseases
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define the term non-communicable disease and distinguish from communicable disease. identify some types of non-communicable diseases state briefly signs, symptoms and management of each of the non-communicable diseases mentioned. state causes and preventive measures for non-communicable diseases
(e.g., salbutamol) for quick relief during an attack.
Controller inhalers: Corticosteroids for long-term management to reduce inflammation.
Avoiding triggers: Identifying and minimizing exposure to allergens and irritants.
Causes: Genetic predisposition, exposure to environmental triggers (allergens like dust mites, pollen, pet dander, mould), irritants (tobacco smoke, air pollution, chemical fumes), respiratory infections, cold air, exercise, stress.
Preventive Measures: Identifying and avoiding personal triggers, adherence to prescribed controller medication, avoiding smoking and exposure to secondhand smoke, managing indoor air quality. b. Chronic Obstructive Pulmonary Disease (COPD) (Includes Emphysema and Chronic Bronchitis)
Definition: A progressive lung disease that causes obstructed airflow from the lungs, making it difficult to breathe.
Signs/Symptoms: Persistent cough (often with mucus), shortness of breath (especially with physical activity), wheezing, chest tightness, frequent respiratory infections.
Management: Bronchodilators, steroids (oral or inhaled), oxygen therapy, pulmonary rehabilitation, smoking cessation.
Causes: Primarily long-term exposure to irritating gases or particulate matter, most often from cigarette smoke (including secondhand smoke). Other factors include exposure to air pollution, dusts, and chemicals, and rarely, a genetic condition called alpha-1 antitrypsin deficiency.
Preventive Measures: Avoiding smoking (most critical), reducing exposure to secondhand smoke and other air pollutants, using protective equipment in occupational settings with dust/chemical exposure. 2.3.
5. Sickle Cell Anaemia Definition: A genetic blood disorder prevalent in Nigeria where red blood cells are abnormally shaped (sickle-shaped) instead of round. These sickle cells can block blood flow, leading to pain crises and organ damage. Nigeria has the highest burden of sickle cell disease globally.
Signs/Symptoms: Chronic anaemia, recurrent painful crises (vaso-occlusive crises, often in bones, chest, abdomen), fatigue, jaundice (yellowing of skin/eyes), swelling of hands and feet (dactylitis in infants), increased susceptibility to infections, acute chest syndrome, stroke.
Management: Pain management (analgesics). Hydration. Antibiotics for infections. Blood transfusions. Hydroxyurea (a medication that helps reduce complications). Folic acid supplementation. Bone marrow transplant (curative but complex and rare).
Causes: Inherited genetic mutation. An individual must inherit two copies of the sickle cell gene (HbSS genotype), one from each parent, to have the disease. Carriers (HbAS) have sickle cell trait and are generally asymptomatic but can pass the gene to their children.
Preventive Measures: Genetic counselling and screening (genotype testing) for prospective parents before marriage to understand the risk of having a child with sickle cell anaemia. Prenatal diagnosis can also be done. It is not possible to prevent the disease in an individual who has inherited the genes, but its transmission can be prevented through informed reproductive choices. 2.3.
6. Deficiency Diseases Definition: Conditions resulting from an inadequate intake or absorption of one or more essential nutrients (vitamins, minerals, protein, calories).
Examples Relevant to Nigeria: Protein-Energy Malnutrition (PEM): Kwashiorkor: Primarily protein deficiency, often seen in children after weaning.
Signs/Symptoms: Swollen abdomen and feet (edema), skin lesions, reddish-brown hair, apathy, stunted growth.
Marasmus: Severe deficiency of overall energy (calories) and protein.
Signs/Symptoms: Severe wasting of muscle and fat, extreme thinness, stunted growth, prominent bones, "old man's face." Iron Deficiency Anaemia: Causes: Insufficient iron intake, chronic blood loss (e.g., hookworm infection common in rural Nigeria), poor absorption.
Signs/Symptoms: Fatigue, paleness, weakness, shortness of breath, dizziness.
Vitamin A Deficiency: Causes: Inadequate intake of Vitamin A-rich foods.
Signs/Symptoms: Night blindness (nyctalopia), dry eyes (xerophthalmia), impaired immunity.
Iodine Deficiency Disorders (IDD): Causes: Insufficient iodine intake, common in inland areas away from seafood sources.
Signs/Symptoms: Goitre (enlarged thyroid gland), cretinism (severe mental and physical retardation if deficiency occurs during fetal development). Rickets (in children) / Osteomalacia (in adults): Causes: Vitamin D deficiency and/or calcium deficiency.
Signs/Symptoms: Softening and weakening of bones, bone pain, bowed legs in children.
Management: Dietary supplementation with the deficient nutrient, therapeutic feeding (for severe malnutrition), education on balanced nutrition.
Causes: Inadequate dietary intake due to poverty, food insecurity, lack of knowledge, poor food preparation, malabsorption issues, increased nutrient requirements (e.g., pregnancy, lactation, rapid growth).
Preventive Measures: Promoting a balanced diet (eating from all food groups, e.g., using local staples like leafy vegetables, legumes, fortified flours). Food fortification programmes (e.g., iodization This section provides in-depth explanations of the core concepts related to Non-Communicable Diseases (NCDs), their types, signs, symptoms, management, causes, and prevention, with an emphasis on relevance to the Nigerian context. 2.
1. Definition of Non-Communicable Disease (NCD) Non-communicable diseases (NCDs), also known as chronic diseases, are medical conditions or diseases that are non-infectious and cannot be transmitted directly from one person to another. They are typically long-duration and result from a combination of genetic, physiological, environmental, and behavioural factors. Unlike communicable diseases, NCDs are not caused by pathogens like bacteria, viruses, fungi, or parasites. 2.
2. Distinction from Communicable Diseases The primary difference lies in their mode of transmission and aetiology (causes). | Feature | Non-Communicable Diseases (NCDs) | Communicable Diseases (CDs) | | :----------------- | :------------------------------------------------------ | :----------------------------------------------------------- | | Transmission | Not transmitted from person to person. | Transmitted from person to person, animal to person, or from the environment. | | Causes | Lifestyle, genetics, environment, metabolism, age. | Pathogens (bacteria, viruses, fungi, parasites). | | Duration | Typically chronic (long-lasting). | Can be acute (short-term) or chronic. | | Infectious | Non-infectious. | Infectious. | | Examples | Hypertension, Diabetes, Cancer, Sickle Cell Anaemia. | Malaria, Tuberculosis, HIV/AIDS, Cholera, COVID-19. | | Prevention Focus | Lifestyle modification, health screenings, genetic counselling. | Vaccination, hygiene, vector control, safe sex, antibiotics. |
Example: A person with hypertension (an NCD) cannot pass their high blood pressure to another person through contact. Its development is linked to factors like diet, exercise, and genetics. A person with Malaria (a CD) can transmit the disease to another person if an infected mosquito bites them, or if blood is transfused. Its development is linked to the Plasmodium parasite. 2.
3. Types of Non-Communicable Diseases (NCDs) This section details common NCDs, focusing on their specific signs, symptoms, management, causes, and preventive measures. 2.3.
1. Cardiovascular Diseases (CVDs) These are diseases of the heart and blood vessels. a. Hypertension (High Blood Pressure)
Definition: A condition where the blood pressure in the arteries is persistently elevated. It's often called the "silent killer" because it usually has no obvious symptoms.
Signs/Symptoms: Often asymptomatic. When severe, symptoms can include headaches, dizziness, blurred vision, nosebleeds (epistaxis), chest pain, shortness of breath.
Management: Lifestyle modifications: Regular exercise, healthy diet (low salt, high fruits/vegetables), maintaining a healthy weight, stress management, limiting alcohol, quitting smoking.
Medication: Antihypertensive drugs prescribed by a doctor (e.g., diuretics, beta-blockers, ACE inhibitors).
Causes: Genetic predisposition, obesity, high intake of salt, sedentary lifestyle, excessive alcohol consumption, stress, smoking, chronic kidney disease.
Preventive Measures: Regular physical activity, a balanced diet low in processed foods and saturated fats, reduced salt intake (e.g., limiting canned foods, seasoning cubes, processed snacks common in Nigeria), maintaining a healthy body weight, avoiding smoking and excessive alcohol. b. Coronary Artery Disease (CAD) / Heart Attack Definition: CAD occurs when the blood vessels that supply blood to the heart (coronary arteries) become narrowed or blocked by plaque buildup (atherosclerosis). A heart attack (myocardial infarction) occurs when blood flow to a part of the heart is blocked, causing heart muscle damage.
Signs/Symptoms: Chest pain (angina, often described as tightness, pressure, or squeezing, radiating to the arm, shoulder, jaw, or back), shortness of breath, sweating, nausea, lightheadedness, extreme fatigue.
Management: Emergency care: Aspirin, nitrates.
Long-term: Medications (e.g., statins for cholesterol, beta-blockers), angioplasty (stent placement), coronary artery bypass grafting (CABG) surgery.
Lifestyle changes: Similar to hypertension prevention.
Causes: Atherosclerosis (plaque buildup in arteries), high blood cholesterol, hypertension, diabetes, smoking, obesity, lack of physical activity, family history.
Preventive Measures: Healthy diet (low in saturated/trans fats, cholesterol), regular exercise, maintaining healthy weight, managing blood pressure and diabetes, avoiding smoking. 2.3.
2. Diabetes Mellitus Definition: A chronic condition that occurs when the body either does not produce enough insulin (Type 1) or cannot effectively use the insulin it produces (Type 2). Insulin is a hormone that regulates blood sugar. Types (Focus on Type 2 for general prevention): Type 1 Diabetes: An autoimmune condition where the body's immune system destroys the insulin-producing cells in the pancreas. Usually family history.
Preventive Measures: Healthy diet (low in saturated/trans fats, cholesterol), regular exercise, maintaining healthy weight, managing blood pressure and diabetes, avoiding smoking. 2.3.
2. Diabetes Mellitus Definition: A chronic condition that occurs when the body either does not produce enough insulin (Type 1) or cannot effectively use the insulin it produces (Type 2). Insulin is a hormone that regulates blood sugar. Types (Focus on Type 2 for general prevention): Type 1 Diabetes: An autoimmune condition where the body's immune system destroys the insulin-producing cells in the pancreas. Usually diagnosed in children and young adults.
Type 2 Diabetes: The most common type. The body becomes resistant to insulin or doesn't make enough insulin. Often linked to lifestyle factors.
Gestational Diabetes: Develops during pregnancy.
Signs/Symptoms: Frequent urination (polyuria), increased thirst (polydipsia), increased hunger (polyphagia), unexplained weight loss, fatigue, blurred vision, slow-healing sores or frequent infections, tingling/numbness in hands/feet.
Management: Dietary control: Reduced intake of sugary drinks and refined carbohydrates (e.g., limiting fufu, garri, rice portions, and sugary snacks), balanced meals with emphasis on fibre-rich foods.
Regular exercise: Improves insulin sensitivity.
Medication: Oral hypoglycemic agents (for Type 2), insulin injections (for Type 1 and some Type 2). Blood glucose monitoring.
Causes: Genetic predisposition, obesity, sedentary lifestyle, poor diet (high in processed sugars and unhealthy fats), age. In Nigeria, changing dietary habits towards more processed foods and sugary drinks contributes to its rise. Preventive Measures (especially for Type 2): Maintaining a healthy body weight, regular physical activity, a balanced diet rich in whole grains, fruits, and vegetables, and low in processed foods, sugary drinks, and unhealthy fats. 2.3.
3. Cancers Definition: A group of diseases characterized by the uncontrolled growth and spread of abnormal cells. These cells can invade and destroy healthy tissues.
Common Types in Nigeria: Breast cancer, cervical cancer, prostate cancer, liver cancer, colorectal cancer.
Signs/Symptoms: Vary widely depending on the type and location of cancer. General signs can include unexplained weight loss, persistent fatigue, unusual lumps or swellings, changes in bowel or bladder habits, persistent cough or hoarseness, unexplained bleeding or discharge, skin changes (e.g., new mole or change in an existing mole).
Management: Surgery, chemotherapy, radiation therapy, targeted therapy, immunotherapy, hormone therapy. The choice of treatment depends on the type, stage, and location of the cancer.
Causes: Genetic predisposition: Family history of certain cancers.
Lifestyle factors: Tobacco use (smoking, chewing), harmful use of alcohol, unhealthy diet (low fruits/vegetables, high processed meats), obesity, physical inactivity.
Environmental factors: Exposure to carcinogens (e.g., asbestos, radiation), air pollution.
Infections: Human Papillomavirus (HPV) for cervical cancer, Hepatitis B virus (HBV) for liver cancer, Human Immunodeficiency Virus (HIV) for Kaposi's sarcoma.
Age: Risk generally increases with age.
Preventive Measures: Healthy lifestyle (avoiding tobacco, moderate alcohol intake, balanced diet, regular exercise, maintaining healthy weight). Vaccinations (e.g., HPV vaccine for cervical cancer, HBV vaccine for liver cancer). Regular screenings and early detection (e.g., mammograms for breast cancer, Pap tests for cervical cancer, prostate-specific antigen (PSA) test for prostate cancer). Avoiding excessive sun exposure. Minimizing exposure to environmental and occupational carcinogens. 2.3.
4. Chronic Respiratory Diseases These affect the airways and other structures of the lungs. a.
Asthma Definition: A chronic inflammatory disease of the airways that causes periodic attacks of wheezing, shortness of breath, chest tightness, and coughing.
Signs/Symptoms: Wheezing (a whistling sound during breathing), shortness of breath (dyspnea), chest tightness, coughing (especially at night or early morning, or after exercise).
Management: Reliever inhalers: Bronchodilators (e.g., salbutamol) for quick relief during an attack.
Controller inhalers: Corticosteroids for long-term management to reduce inflammation.
Avoiding triggers: Identifying and minimizing exposure to allergens and irritants.
Causes: Genetic predisposition, exposure to environmental triggers (allergens like dust mites, pollen, pet dander, mould), irritants (tobacco smoke, air pollution, chemical fumes), respiratory infections, cold air, exercise, stress.
Preventive Measures: Identifying and avoiding personal triggers, adherence to prescribed controller medication, avoiding smoking and exposure to secondhand smoke, managing indoor air quality. b. Chronic Obstructive Pulmonary Disease (COPD) (Includes Emphysema and adults): Causes: Vitamin D deficiency and/or calcium deficiency.
Signs/Symptoms: Softening and weakening of bones, bone pain, bowed legs in children.
Management: Dietary supplementation with the deficient nutrient, therapeutic feeding (for severe malnutrition), education on balanced nutrition.
Causes: Inadequate dietary intake due to poverty, food insecurity, lack of knowledge, poor food preparation, malabsorption issues, increased nutrient requirements (e.g., pregnancy, lactation, rapid growth).
Preventive Measures: Promoting a balanced diet (eating from all food groups, e.g., using local staples like leafy vegetables, legumes, fortified flours). Food fortification programmes (e.g., iodization of salt, Vitamin A fortification of sugar/flour). Nutritional education for mothers and caregivers. Addressing underlying causes like poverty and food insecurity. 2.3.
7. Mental Health Disorders (Briefly covered as they are NCDs with increasing recognition)
Definition: Conditions that affect thinking, feeling, mood, or behaviour. They can be occasional or long-lasting (chronic).
Examples: Depression, anxiety disorders, schizophrenia, bipolar disorder.
Signs/Symptoms: Persistent sadness, loss of interest/pleasure, changes in sleep or appetite, fatigue, difficulty concentrating, excessive worry, social withdrawal, hallucinations, delusions (vary greatly by disorder).
Management: Psychotherapy (counselling), medication (antidepressants, anxiolytics, antipsychotics), support groups, lifestyle changes (exercise, mindfulness).
Causes: Genetic predisposition, biological factors (brain chemistry), psychological factors (trauma, stress), environmental factors.
Preventive Measures: Stress management techniques, building resilience, fostering supportive social networks, seeking help early for mental distress, promoting mental health awareness and reducing stigma. 2.
4. General Causes of NCDs These are overarching factors contributing to most NCDs.
Behavioural Risk Factors: Tobacco use: Smoking, secondhand smoke, chewing tobacco.
Harmful use of alcohol: Excessive consumption.
Unhealthy diet: High intake of salt, sugar, unhealthy fats; low intake of fruits, vegetables, and whole grains.
Physical inactivity: Sedentary lifestyle.
Metabolic Risk Factors: These often result from behavioural risk factors. Raised blood pressure (Hypertension). Overweight and Obesity. Raised blood glucose (Hyperglycemia). Raised cholesterol (Dyslipidemia).
Environmental Factors: Air pollution (indoor from biomass fuels, outdoor from industrial emissions/vehicles), exposure to occupational hazards (chemicals, dust).
Genetic Predisposition: Family history increases susceptibility to many NCDs (e.g., diabetes, certain cancers, hypertension, sickle cell).
Age: The risk of many NCDs generally increases with age. 2.
5. General Preventive Measures for NCDs These are broad strategies applicable to most NCDs.
Promoting Healthy Lifestyles: Healthy diet: Emphasize local, nutritious foods (e.g., whole grains, fruits like garden eggs and pawpaw, vegetables like ugu and scent leaf, lean protein). Reduce intake of processed foods, sugary drinks, and excessive salt/fats.
Regular physical activity: Encourage activities like walking, jogging, dancing, farming, or sports.
Tobacco cessation: Implement and enforce policies against tobacco use, provide support for quitting.
Moderate alcohol consumption: Discourage harmful use of alcohol.
Regular Health Screenings: Early detection of risk factors (e.g., blood pressure checks, blood sugar tests, cholesterol levels) and early diagnosis of diseases (e.g., cancer screenings).
Early Diagnosis and Treatment: Ensuring access to timely and appropriate healthcare to manage NCDs and prevent complications.
Environmental Health Promotion: Reducing exposure to air pollution, ensuring access to clean water and sanitation.
Public Health Awareness Campaigns: Educating the public about NCD risks, symptoms, and preventive measures using culturally appropriate messages (e.g., radio jingles in local languages, community outreaches).
Genetic Counselling:** For hereditary diseases like sickle cell anaemia.
This topic has profound relevance to the daily lives of Nigerian students and their communities. Understanding NCDs extends beyond the classroom, impacting individual health choices and broader societal well-being.
Community Health Advocacy and Awareness: Application: Students can become advocates for NCD prevention in their families and local communities. For example, they can educate elderly relatives on the importance of regular blood pressure checks (for hypertension) or advise neighbours on reducing excessive salt/sugar intake in local meals (to prevent diabetes and hypertension). They can participate in or initiate school-based health campaigns using posters or drama to raise awareness about NCDs like cervical cancer prevention through HPV vaccination or the importance of genotype testing before marriage for sickle cell anaemia.
Nigerian Context: Many rural and semi-urban communities in Nigeria still rely on traditional medicine or are unaware of NCD risks. Educated students can bridge this knowledge gap, promoting early screening and health-seeking behaviours, especially considering the prevalence of NCDs like diabetes and hypertension among adults and sickle cell anaemia across diverse demographics. Economic Impact on Families and Healthcare: Application: Students can analyze how NCDs financially burden Nigerian families and the national healthcare system. For instance, a family with a member suffering from uncontrolled diabetes or cancer might face significant out-of-pocket expenses for medication, hospital visits, and dietary changes, potentially leading to poverty or diversion of funds from education or other essential needs. This understanding can motivate students to prioritize preventive health, recognizing the long-term economic benefits of a healthy lifestyle.
Nigerian Context: With limited universal health coverage and many Nigerians relying on personal funds for healthcare, NCDs can be catastrophic. Students can appreciate how preventive measures like healthy eating (using local, affordable nutritious foods) and physical activity (which is free) are economically viable alternatives to expensive treatments.
Cultural Practices and Dietary Shifts: Application: The lesson can integrate discussions on how changing cultural practices and dietary habits in Nigeria contribute to NCDs. For example, the shift from traditional, fibre-rich diets (e.g., local soups with vegetables, whole grains like millet and guinea corn) to more processed foods, fast food, and sugary drinks, particularly in urban areas, can be linked to the rise of obesity, diabetes, and cardiovascular diseases. Students can critically evaluate their own and their community's dietary patterns and suggest healthier cultural adaptations that retain heritage while promoting health.
Nigerian Context: Many Nigerian traditional foods are inherently healthy, but modernization has introduced less healthy options. Students can be encouraged to champion a return to healthier traditional diets and active lifestyles (e.g., farming, walking long distances) that were once common but are now being replaced by sedentary habits and processed foods.