Dear Doctor: I’m a 56-year-old man. I have been out of breath lately and have had some mild chest pains. My doctor wants me to have a stress test. Is it really necessary? What will it entail?

Dear Reader: The purpose of a stress test is to see how someone’s heart behaves when it’s being asked to work hard. These types of tests have a number of uses. For instance, they can help assess general cardiac health; identify and evaluate various types of heart disease or arrhythmias; and help to gauge the success of medications or treatments for cardiac-related ailments.

For people living with heart disease or recovering from a cardiac event, a stress test can help pinpoint the type and intensity of exercise that is safe. A stress test can also be used to confirm whether certain symptoms, which can have a variety of causes, are heart-related. This includes the shortness of breath and chest discomfort that you have described.

The most common stress tests involve walking on a treadmill or riding a stationary bicycle. While the person exercises, a variety of devices measure and monitor blood pressure, heart rate, oxygen saturation and the electrical activity of the heart. Some stress tests, which evaluate lung function, will measure oxygen use. The activity level of a stress test begins low and slow, then gradually increases. The idea is that, as the heart is asked to work harder and harder, underlying problems may be revealed. This can include the onset of physical symptoms such as dizziness, unusual breathlessness or chest pain, or abnormal changes to the electrical activity of the heart.

When you schedule a stress test, you’ll be asked to stop eating or drinking for a set period of time before the test begins, generally a few hours. You will also be instructed not to smoke and to abstain from alcohol and caffeine. Your doctor will ask you what medications and supplements you take on a regular basis, and will let you know if any of them need to be paused. If you have asthma and use an inhaler, be sure to let your doctor know, and bring the inhaler with you.

Electrodes to capture the electrical activity of your heart are taped to various parts of your chest, and a blood pressure cuff is attached to your arm. A pulse oximeter, to measure blood-oxygen saturation, may be clipped to a finger. During the active portion of the test, usually 10 to 15 minutes, you will exercise at an increasingly higher rate, until you reach a target goal. If symptoms develop at any point, the test is cut short. These can include chest pain, dizziness, shortness of breath and abnormal changes to blood pressure or electrical activity. It’s important to let the tech administering the test know if you feel discomfort at any time. Monitoring may continue after the test is complete to see how the heart and body recover.

Within the next few days, your doctor will review the test results with you. If coronary disease is suspected, either treatment or additional testing may be recommended.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10880 Wilshire Blvd., Suite 1450, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: Everyone talks about girls getting the HPV vaccine. But what about boys? Isn’t it just as important for boys to be vaccinated as well?

Dear Reader: You’re referring to the vaccination for human papillomavirus, or HPV. And you’re correct that the vaccination is important for both girls and boys. HPV is the most common sexually transmitted infection in the United States, and it can lead to several types of cancer later in life. About 80 million people in the U.S. are currently infected with some type of the virus. About 14 million more, mostly teens and young adults, become infected every year.

HPV refers to a group of more than 200 related viruses. Of these, more than 40 are spread through direct sexual contact. The majority of HPV infections clear up on their own, often in about two years. The rest, however, can linger. They can lead to health problems that range from mild to life-threatening. Some cause genital warts and are considered to be low-risk. Others can cause cancers in different parts of the body. In women, certain types of HPV can cause cancer of the cervix, vulva and vagina. In fact, most cases of cervical cancer are associated with HPV. In men, the viruses can cause penile cancer. They can also lead to anal cancer, and to cancers of the mouth and throat, each of which can occur in either gender. Men can also be carriers of the types of HPV that put women at risk.

The first HPV vaccine won approval from the Food and Drug Administration in 2006. Today, an updated vaccine protects against nine strains of HPV. It has been extensively tested and found to be safe. Side effects can include swelling, pain or bruising at the injection site. Some people report temporary headache, dizziness, fever or nausea. There is no evidence that the vaccine causes any long-term side effects. When administered before an individual becomes sexually active, the vaccine has been found to be highly effective in preventing the infections it targets.

The HPV vaccine is recommended for all children and adults from ages 9 through 26. The CDC recommends a two-dose schedule of the vaccine for children younger than 15. The second dose is given six to 12 months after the first. For teens and young adults who haven’t been vaccinated before the age of 15, three doses administered over six months is recommended. Although use of the HPV vaccine has been approved for people older than 26, it’s important to talk to your health care provider to see whether it will be beneficial.

For anyone on the fence, consider this: HPV infections cause an estimated 35,000 cases of cancer in men and women each year. But since the advent of the vaccine, infections in teen girls that lead to genital warts and most HPV cancers have dropped 86%. Young adult women have seen a decline of 71%. And among vaccinated women, HPV-related precancers linked to cervical cancer have dropped 40%. As the data show, the HPV vaccine saves lives.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10880 Wilshire Blvd., Suite 1450, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: I tripped while I was out running a few months ago and got pretty banged up, including a knock to the head. My wife worried about a concussion and wanted me to see a doctor. How do you know if you have a concussion?

Dear Reader: A concussion is a type of brain injury that can occur when a force is powerful enough to cause the head, along with the brain inside of it, to shake quickly back and forth. This can result from the type of direct impact you experienced when you fell during your run. It may also be caused by an indirect force that’s powerful enough to make the head whip back and forth, as can happen during a tackle or when you’re rear-ended in your car at high speed.

Your brain is basically a passenger within your skull. When something causes your head to stop short or suddenly change direction, your brain continues moving. It bounces and twists and bumps into the interior surfaces of the skull. A concussion results in a chemical change within the brain, along with bruises, tears or injury to the soft and fragile tissues. Because it’s not life-threatening, concussion is typically referred to as a mild traumatic brain injury, or TBI. However, the effects can be serious.

When you have a concussion, symptoms may show up right away, or they can develop over a period of hours or days. Immediately after a concussion, a person may appear dazed or bewildered. They may not immediately be aware of what happened, and it’s possible they won’t recall the moments leading up to the injury. Some people become clumsy, and they may have trouble understanding and following directions. Physical symptoms can include headache, feeling nauseated, vomiting, a feeling of pressure within the skull, blurred or double vision, ringing in the ears and problems with balance and coordination. Some people may develop a sensitivity to external stimuli, including light and sound. The person may report feeling slow or groggy or just generally not OK. A brief loss of consciousness immediately after impact is possible.

Someone with a suspected concussion should seek medical care. You’ll be asked for details about the accident, as well as any symptoms. It’s important to also share information about any medications and supplements, as some can increase risk of bleeding. Diagnosis includes a neurological exam that checks vision, hearing, strength, balance and coordination. Cognitive tests are used to evaluate memory, recall and concentration. It’s possible that someone would be asked to stay overnight in a hospital for observation. In some cases, brain imaging tests may be considered.

In 2018, the U.S. Food and Drug Administration approved a blood test to evaluate concussion. It measures levels of two protein biomarkers that the brain releases into the blood within 12 hours of a head injury. It’s not a diagnostic test for concussion, but it does help predict which patients will have injuries that will be visible in a brain scan.

With 3.8 million reported concussions per year, this is a common injury. It’s also a potentially serious one. It’s important, so we’ll say it again: If you suspect a concussion, seek medical care.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10880 Wilshire Blvd., Suite 1450, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)