Chronic Disease Screening and Prevention

What is Screening?

• The primary goal of healthcare is to prevent disease or detect it early enough that interventions will be more effective.
• Preventing a disease is more important than treating it.

Levels of Prevention

• Primary prevention aims to remove or reduce disease risk factors (e.g., health education, vaccination, specific protection).
• Secondary prevention techniques promote early detection of disease or precursor states (e.g., routine screening).
• Tertiary prevention measures are aimed at limiting the impact of established disease (treat complications and limit disability).

Definition

• Screening is the application of a test to detect potential health disorder or disease in a population who has no overt sign or symptom of the disease in question.
• Screening is a form of secondary level of prevention and may be stratified, e.g., age or gender-specific.
• It is not considered diagnostic but meant to identify people who require further investigation to determine presence or absence of a disease.

Why Screening?

The main purpose of screening is to detect early evidence(s) of a disease in order to recommend preventive strategies or treatments that will provide better health outcomes than if the disease were diagnosed at a later stage.

According to WHO, a condition that is recommended for screening must fulfill the following criteria:

1. It should be an important health problem.
2. There should be a recognizable early latent or symptomatic stage.
3. The natural history of the condition, including the development from latent to declared disease, should be adequately understood.
4. There should be accepted treatment for the recognized disease.
5. There should be a suitable test or examination that has a high level of accuracy for the condition.
6. The test should be acceptable to the population.
7. There should be an agreed policy on whom to treat as a patient.
8. Facilities for diagnosis and treatment should be available.
9. The cost of screening (including diagnosis and treatment) should be economically balanced in relation to possible expenditure on medical care as a whole.
10. The screening should be a continuing process and not a once-and-for-all project.

• It should be suitable and acceptable.
• It should be readily available.
• It should be valid (distinguishes between disease and non-disease), i.e., highly sensitive and extremely specific.
• Screening should be cost-effective (inexpensive).
• Screening should be safe (low risk).
• It should be reliable (i.e., consistent results with repeated tests).
• It should be easy to administer.
• It should cause minimal discomfort.

• Recently, there has been an unprecedented rise in the prevalence, complications, and mortalities from chronic medical diseases in Nigeria and some other developing countries.
• In 2018, WHO reported the prevalence of Non-communicable diseases (NCDs) in Nigeria to stand at 29%, with cardiovascular diseases (hypertension, stroke, and coronary artery diseases) having the highest prevalence (11%).
• Also, according to WHO country profile in 2018, NCDs accounted for 29% of all recorded deaths in Nigeria, with cardiovascular diseases as the major primary cause.
• Primary prevention and screening for chronic diseases are considered as the best hope to curtail this vice.

Screening (18 – 64 years) Men
Screening Test	Age to start	Frequency
Blood pressure	> 18 years	Periodically
Height and Weight	> 18 years	Periodically
Cholesterol	35 to 65 years	Every 5 years
Fasting glucose	> 45 years Earlier if there are positive risk factors	Every 3 years
Digital rectal examination	> 40 years	Every year
Faecal occult blood	> 50 years	Every year
Sigmoidoscopy	> 50 years	Every 3 years
Colonoscopy	> 50 years	Every 5 years
Excessive Alcohol use	> 18 years	Periodically
PSA	> 50 years	Every year

Screening (18 – 64 years) Women
Screening Tool	Age to start	Frequency
Blood pressure	> 18 years	Periodically
Height and Weight	> 18 years	Periodically
Cholesterol	45 to 65 years	Every 5 years
Fasting glucose	45 years Earlier if there are positive risk factors	Every 3 years
Papanicolaou (Pap) test	Sexually active or previously sexually active with a cervix	Every 1 – 3 years
Clinical breast examination	> 40 years	Every year
Mammography	> 40 years	Every 1 - 2 years
Digital rectal examination	> 40 years	Every year
Faecal occult blood	> 50 years	Every year
Sigmoidoscopy	> 50 years	Every 3 years
Colonoscopy	> 50 years	Every 5 years
Osteoporosis	> 60 years in women at risk	Periodically
Excessive Alcohol use	> 18 years	Periodically

Screening (65 years and older) Men
Screening Tool	Age to start	Frequency
As for men aged 18 – 64years
Vision screening Refractive errors Macular degeneration Glaucoma Cataract	> 65 years	Periodically
Assessment of hearing impairment Presbycusis	> 65 years	Periodically

Screening 65years and Older Women
Screening Tool	Age to start	Frequency
As for Women aged 18 – 64years
Vision screening Refractive errors Macular degeneration Glaucoma Cataract	> 65 years	Periodically
Assessment of hearing impairment Presbycusis	> 65 years	Periodically
Papanicolaou (pap) test	Sexually active & who have a cervix. If previous tests were normal, discontinue at 65 years
Clinical breast examination	Discontinue at 70 years	No proven benefit
Mammogram	Discontinue at 70 years	No proven benefit

Routine Mammography

• Between 50 – 69 years: Results in 25% reduction in mortality.
• 40 – 49 years: No clear benefit.
• 70 – 75 years: Conflicting evidence on benefit.
• > 75 years: No clear benefit.

Pap Smear

• 70% decrease in mortality.
• ACOG: Every 1 – 3 years from age of 18 years.
• AAFP: At least every 3 years in sexually active or previously sexually active women with a cervix.
• Some others: Every 1-3 years starting 3 years after the first sexual exposure or age 21 years.
• Upper age limit is controversial, but after 65 years only 0.18% decrease in mortality.

DRE (Digital Rectal Examination)

• Low sensitivity.
• Less than 10% of rectal carcinoma lie within the reach of the examining finger.
• Less than 33% of prostatic carcinoma occur in areas accessible to palpation.
• Prostatic carcinoma large enough to be palpated are usually advanced and less amenable to treatment.

Colonoscopy

• Not cost-effective.
• Useful only in patients with risk factors.

Excessive Alcohol Use

• Occurs in 10% of the USA population.
• AUDIT (Alcohol Use Disorder Identification Test).
• Screen at first visit.

PSA (Prostate-Specific Antigen)

• Concerns over its specificity for clinically significant carcinoma.
• False positive in BPH and Prostatitis.
• 25 – 38% of asymptomatic men found positive.
• American Cancer Society recommends yearly screening.
• AAFP uncertain about its benefit, recommends vigilance.

• Risk factors can be modifiable or unmodifiable.
• Chronic diseases tend to share a number of modifiable risk factors.
• Modifiable risk factors can be classified into two:
1. Behavioral risk factors:
   • Tobacco smoking
   • Alcohol use
   • Unhealthy diet
   • Physical inactivity
2. Biological risk factors:
   • Overweight
   • Obesity
   • High blood pressure
   • Elevated blood glucose
   • Abnormal blood lipids

According to Nigeria's prevention policy and strategies of NCDs, there are four notable modifiable risk factors for common chronic medical illnesses:

• Tobacco use and exposure to secondhand smoke
• Harmful alcohol use
• Unhealthy diet
• Physical inactivity

Lifestyle Modification

One of the major ways to prevent chronic diseases is to live healthily.

Diets:

• Plant-based, whole-grain food diet, less sugar, less refined carbohydrates.
• Beans, rice, maize, sorghum, etc., are better than animal-based meals like fish, meat, milk, butter.
• Fish, especially dried ones, are better than meat. White meat is better than red meat.
• Increase intake of fruits, vegetables, legumes, whole grains, and nuts.
• Increase intake of dietary fibers (vegetables and fruits).
• Follow the "five courses of vegetable and fruit per day" rule.
• Frequency: 3 times daily. Avoid extra meals and snacks, especially if there is a need to shed weight.
• Timing: Breakfast - before 12 noon, Lunch between 12 and 4 pm, Dinner before 7 pm. You need to still be active for 2-3 hours after your last meal before you go to bed.
• Quantity: Moderate quantity. Largest - breakfast, smaller - lunch, smallest - dinner.

Tobacco and Alcohol Use

• Stop tobacco use (smoke or non-smoke form).
• Avoid passive smoking.
• Cut down or stop alcohol use.
• There is no completely safe level of alcohol consumption, but limiting oneself within the guideline lowers the risk of harm caused by alcohol.
• The recommended limits for a healthy man and woman are 3-4 units per day and 2-3 units per day, respectively.

Activity/Exercise

• Be active. Avoid a sedentary lifestyle.
• Try and do some things for yourself: wash the car, wash your clothes, clear the garden, mow your lawn, cook the meal.
• Incorporate activities that will require you to move around into your work plan every day.
• Park your car far away from where you are going to enable you to trek some distance.
• Use the staircase instead of the lift.
• Exercise: planned and scheduled activities.
• Exercise is medicine.
• For normal cardiovascular function, aim for 150 mins/week of moderate exercise.
• To lose weight, you need moderate to severe exercises of 1-2 hours per day for 5-6 days per week.
• Grading of exercise (Talk test):
  • Mild: Can comfortably talk, singing during the exercise.
  • Moderate: Can talk but pause in between to breathe.
  • Severe: Unable to talk at all during the exercise.
• Forms of exercise: brisk walking, jogging, running, table tennis, lawn tennis, football, etc.
• Competitive sports, e.g., football, table tennis, help to maintain the habit.
• Involvement of spouse also helps to maintain the habit.

Sleep

• Adults need 7-8 hours of sleep per night.
• Insufficient sleep is associated with heart disease, diabetes, hypertension, obesity, and depression. Strategies for improving sleep initiation and maintenance:
• Consistency in bed and rising time.
• Maintenance of an appropriate sleep environment: quietness, lights out, good bedding, etc.
• Avoid screens (phone/TV) and other disturbances.
• Avoid large meals or extensive exercise before bed.

Stress

• Stress is a state of mental or emotional strain or tension from adverse or very demanding circumstances.
• It is difficult to avoid sometimes.
• Tips on management of stress:
• Be a good time manager and make effective use of your time.
• Avoid procrastination.
• Look for better, faster, and easier ways of doing your job. Take advantage of technology.
• Delegation of duties: What do I want to be done? Is there anybody that can do it under me? Will there be a significant difference when done by another person?
• Time for relaxation: Plan for holiday, take your siesta if possible, try as much as possible not to carry office work home, avoid carrying thoughts of the activities of the day to bed.
• Prayer for Help of God.

Love

• Spend good time with your family and friends.
• Forgive and avoid bitterness.
• Make up your mind to be happy.
• Try and get along with as many people as possible.

Treat the Biological Risk Factors

• Treat obesity and overweight (lifestyle modification mainly).
• Treat high blood pressure (lifestyle modification ± antihypertensive).
• Treat diabetes (lifestyle modification ± antidiabetic agents).
• Treat dyslipidemia (lifestyle modification ± lipid-lowering agents).