It happens sometimes that certain health conditions show symptoms in a healthy person only when it’s too late for proper treatment. You may feel healthy, but your body isn’t actually so. This is where screening tests can make a huge difference. They help keep track of your health and rule out potential risks. Regular health check-ups and tests help doctors initiate timely treatment for a faster road to recovery.  

What are screening tests?

Screening tests are done to detect hidden diseases. It is a preventive measure taken to detect diseases before the body starts showing symptoms. It helps reduce the risk of complications and aids in improving treatment strategies.  Routine screening tests are not diagnostic. In other words, they do not confirm the presence or absence of disease. Screenings can become diagnostic if any abnormality is found during the check-up. 

What are the common screening tests?

Depending on your age, gender, and medical history, your doctor will decide the correct time and frequency of the tests. Generally, the following tests are recommended. 

Tests for both men and women

Lipid profile

Cholesterol is an essential molecule required by your body in certain quantities to perform regular functions. Most of the cholesterol and fats are transported in the bloodstream in the form of lipoproteins. These lipoproteins are present in two forms — low-density lipoprotein (LDL), which is bad cholesterol, and high-density lipoprotein (HDL), which is good cholesterol. 

Bad cholesterol is a risk factor for heart disease, stroke, and clogged arteries. Cholesterol tests are performed by sampling your blood and checking the total amount of cholesterol, LDL, HDL, and triglycerides. 

American Heart Association recommends screening for children (ideally from 9-11 years of age) and for adults from 17 years of age. Due to physiological changes in cholesterol levels during adolescence, routine screening is not recommended during this period. 

Since lipid profiling is not always possible in children and is not recommended by many health agencies, it is advisable to start lipid profile screening from 20 years of age and repeat the tests every five years. 

If you are in the high-risk category for cholesterol disorders, have a family history of cardiovascular disease, or suffer from other lifestyle diseases like diabetes, screenings can start earlier. 

Pre-diabetes and type-2 diabetes 

When you have diabetes, your blood sugar level increases. While fasting blood sugar level in the range of 80 to 100mg/dl in an adult is considered normal, fasting blood sugar level in the range of 100mg/dl to 125mg/dl is considered prediabetes. 

The screening tests for diabetes include random blood glucose (RBG), fasting plasma glucose (FPG), postprandial plasma glucose (PPG), 75g oral glucose tolerance test (OGTT), glycated hemoglobin (HbA1c), and glucose urine. Depending on your risk factors, age, and medical history, your doctor will recommend appropriate tests.

According to the American Diabetes Association, the following people are at high risk: 

• Anyone with a body mass index (BMI) of more than 25, regardless of their age.
• Individuals with comorbidities such as high blood pressure, high cholesterol levels, sedentary lifestyle, polycystic ovary syndrome (PCOS), and family history of diabetes.
• It is suggested that people older than 45 should get tested for diabetes or prediabetes every three years irrespective of weight.
• Women, who have had gestational diabetes, must get screened for diabetes every three years, irrespective of age.
• Anyone with prediabetes or hypertension must undergo screening tests every year.

Also read: Type 2 Diabetes: Causes, Diagnosis and Treatment

Hypertension

Hypertension is an increase in blood pressure. In adults, 120mmHg systolic (contraction of the heart muscle) and 80 mmHg diastolic (relaxation of the heart muscle) is considered normal blood pressure. It is expressed as 120/80mmHg. A blood pressure of < 130/85 mmHg is considered normal. Blood pressure between 131-139mmHg/85-89mmHg is prehypertension. A blood pressure of >140/90mmHg is considered hypertension and requires active intervention and lifestyle changes. If it’s allowed to go unchecked, it can lead to heart attack and stroke.  

If your blood pressure is between 120 to 139mmHg systolic and 80 to 89mmHg  diastolic, then it is prehypertension.

When your blood pressure is above 140/90mmHg, it is considered hypertension. It is a risk factor and can lead to many other diseases such as heart attack and stroke. 

Individuals above 18 with no risk factors can get tested once every two to five years, while people above 40 with or without risk factors can get tested every year. 

Individuals below 40 years of age, who either have hypertension or are in the high-risk category, need repeated assessments every year.

Also read: Hypertension: When Did You Last Check Your Blood Pressure?

Colorectal cancer

Colorectal, also known as bowel, rectal or colon cancer, is the second most common cancer. The British Medical Journal recommends screening for all people aged 50 and above. The following tests are recommended: 

• Stool test – Every year
• Sigmoidoscopy – Doctors examine the rectum and the lower part of the large intestine. This test should be done every five years
• Colonoscopy – Doctors examine rectum of the large intestine. This test should be done every 10 years

High risk individuals (with family history of colon cancer, history of polyps, or suspicion of cancer) should start screening early at the age of 40 or younger, depending on the risk score. In case a parent of an individual suffered from colon cancer, the screening should start 10-20 years before the age at which the parent was diagnosed with cancer.

Skin cancer

If you have a family history of skin cancer, are significantly exposed to the sun, and have a history of sunburn, you should always be on the lookout for abnormal moles, discoloration, and multiple moles.

Sexually-transmitted infections

A sexually active person should get tested for sexually transmitted infections (STIs). STIs are sometimes asymptomatic and early detection can help in faster treatment. The US Centers for Disease Control and Prevention (CDC) recommends the following tests:

• Everyone aged 13 to 64 must be tested for HIV at least once irrespective of whether they are sexually active or not. 
• Women who are sexually active and/ or have multiple sex partners should get tested for chlamydia and gonorrhea every year.
• All pregnant women should get tested for syphilis, HIV, and hepatitis B at the beginning of their pregnancy.
• Sexually active men should get tested for syphilis, chlamydia, and gonorrhea at least once a year. In case of multiple sex partners, the frequency should be at an interval of three to six months.
• Anyone who has had unsafe sex or shared needles needs to get tested for HIV once a year.

Eye screening

Eye examination involves tests conducted for vision and detection of eye diseases. The doctor uses various instruments, bright lights, and lenses to detect an eye condition. Depending on your age, health, and risk factors, the doctor recommends the frequency of an eye exam.  

Age	Eye exam frequency
20-30	Every 5-10 years
40-54	Every 2 years
55-64	Annually
65 and above	Every  1 or 2 years

• If you wear glasses or contact lenses, have a family history or suffer from chronic diseases such as diabetes, then it is advisable to have eye check-ups frequently. 
• Every adult aged 40 and above should get screened for glaucoma and cataract as the signs start showing. 
• In glaucoma, the ophthalmologists check for various parameters such as inner eye pressure, shape and color of the optic nerve, the field of vision, the thickness of the cornea, and angle where the iris and cornea meet. 
• For cataract, the ophthalmologist dilates the eye and checks the optic lens for cloudiness. If you are 60 and above, you must get the dilation test done every two years. 

Dental screening

Dental check-ups are mainly preventive dental care, where the dentist cleans your teeth, checks for cavities and gum diseases. The dentist also examines your face, neck and mouth for any other abnormalities. The dentist may suggest changes in your diet, oral hygiene, and lifestyle to ensure proper dental health. Most dentists recommend dental check-ups twice a year. However, the visits may vary according to your needs.

Tests for women

Pelvic exam

Regardless of sexual history, women who are 20 years of age and above should get a pelvic examination done annually. During the exam, gynecologists will inspect the reproductive organs visually and physically. The doctor will look for symptoms like redness, discharge, irritation, cysts, or sores to rule out any abnormalities, infections, and cancers.

Cervical cancer

Regardless of sexual history, women from the age of 20 should get a pap smear test done every three years to rule out cervical cancer. The examination requires the doctor to scrape off cells from the cervix to check for abnormalities and growth.

Breast cancer

Breast self-examination, along with other screening tools, is an effective way to check for any abnormal lumps and other symptoms related to breast cancer. It is recommended that every woman in the reproductive age group learn the technique and do a breast self-examination every month within the first few days after the start of menstruation. 

Women between the age of 20 to 40 years with a family history of breast cancer are at higher risk, so they must go for the tests. Screening tests include the doctor checking for abnormal growth. In case of family history, the doctor may recommend mammography, genetic testing, and counseling to determine the presence of any genes associated with breast cancer. 

Women between the age of 50 and 74 years should get a mammogram every two years. 

Various organizations recommend varying regimens for regular screening in women below 50 years of age with no apparent risk of developing breast cancer. However, most health agencies recommend that a well-informed decision should be taken by women after discussions with their physician since the procedure is not free from risks like overexposure to radiation, getting false positive, and increasing psychological stress. 

Bone density test

Women aged 65 years and above should ideally get screened for osteoporosis. After menopause, bone density decreases because of a drop in estrogen levels making the bones susceptible to fractures.

Also read: Osteoporosis: Causes, Symptoms and How to Manage It

Tests for men

Prostate cancer

According to the CDC, prostate cancer is common in men. Prostate-specific antigen (PSA) is a protein produced by the prostate cells and normally circulates in the blood. High levels of PSA are linked to prostate cancer even before symptoms begin to appear. If PSA levels are high, doctors recommend a prostate biopsy or digital rectal examination. However, men with lower levels of PSA have also been diagnosed with prostate cancer.

PSA levels may also rise in cases of prostatitis and urinary tract infections (UTIs).

According to the National Cancer Institute, there is no exact normal or abnormal level of PSA, but PSA levels less or equal to 4ng/ml is considered normal. 

According to doctors at Johns Hopkins, men who are 55 years of age and above should get regularly tested as the risk of prostate cancer increases.  

These are a few tests to keep your health in check and help detect underlying disorders and diseases. Prevention is better than cure, so don’t hesitate. Schedule your medical check-ups today. 

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