If you’re one of the more than 14.8 million American adults who experiences major depression, you may feel so bad that you can’t get out of bed, be around the people you love or participate in activities that you usually enjoy. Actually, there are more than 50 different symptoms of major depression, ranging from the well-known—crying and sadness—to those you might never associate with depression, such as anger, workaholism and back pain.

Depression is a disease that affects every aspect of a person’s life, not just mood, says Johns Hopkins expert Andrew Angelino, M.D., Chair of Psychiatry at Howard County General Hospital. The World Health Organization predicts that by 2020, depression will be the second-leading cause of disability in the world, just behind cardiovascular disease.

People who are depressed are far more likely to have other chronic medical conditions, including cardiovascular disease, back problems, arthritis, diabetes, and high blood pressure, and to have worse outcomes. Untreated depression can even affect your immune response to some vaccines.

Depression is not just debilitating; it can be deadly. An estimated one out of five people with depression will attempt suicide at some point.

Causes and Risk Factors

Depression is not a mood you can just get over. It is a disease in which the brain ceases to register pleasurable activities, says Angelino. Indeed, MRI studies with depressed people have found changes in the parts of the brain that play a significant role in depression.

Women are about twice as likely as men to be diagnosed with depression. You’re also more likely to develop depression if you are between ages 45 and 64, nonwhite, or divorced, and if you never graduated high school, can’t work or are unemployed, and don’t have health insurance. Other risks for depression include factors such as these:

• Experiencing stressful events in your life, such as losing your job, having problems in your marriage, major health problems, and/or financial challenges.
• Having a bad childhood, such as one involving abuse, poor relationships with your parents, and/or your parents own marital problems.
• Certain personality traits, such as getting extremely upset when you’re stressed.
• A family history of depression, which can increase your own risk three or four times.

Depression is far more common than you might think, with nearly one out of 10 adults depressed at any time, about half of them severely.

Symptoms and Diagnosis

Symptoms of depression vary widely but can be divided into three main categories:

• Emotional and cognitive (thinking) symptoms include a depressed mood, lack of interest or motivation in things you typically enjoy, problems making decisions, irritability, excessive worrying, memory problems and excessive guilt.
• Physical symptoms include fatigue, sleep problems (such as waking too early, problems falling or staying asleep, sleeping too much), changes in appetite, weight loss or gain, aches and pains, headaches, heart palpitations, and burning or tingling sensations.
• Behavioral symptoms include crying uncontrollably, having angry outbursts, withdrawing from friends and family, becoming a workaholic, abusing alcohol or drugs, cutting or otherwise hurting yourself, and, in the worst cases, considering or attempting suicide.

Depression can be classified as:

• Major depressive disorder (MDD), which includes depressed mood and/or reduced interest and pleasure in life, considered “core” symptoms, and other symptoms that significantly affect daily life.
• Dysthymia, (dis-THI-me-a), a milder form of depression that can progress to MDD.
• Postpartum depression, which occurs within weeks of giving birth.
• Psychotic depression, which comes with delusions and/or hallucinations.
• Seasonal affective depression, which occurs as the days get shorter and improves with spring.

#TomorrowsDiscoveries: How the Brain Processes Incentives and Rewards | Vikram S. Chib, Ph.D.

- Watch on YouTube

Johns Hopkins researcher Vikram S. Chib studies the way incentives and rewards work in the brain and how this can lead to breakthroughs in depression treatment.

Definitions

Cardiovascular (car-dee-oh-vas-cue-ler) disease: Problems of the heart or blood vessels, often caused by atherosclerosis—the build-up of fat deposits in artery walls—and by high blood pressure, which can weaken blood vessels, encourage atherosclerosis and make arteries stiff. Heart valve disorders, heart failure and off-beat heart rhythms (called arrhythmias) are also types of cardiovascular disease.

Cognitive behavioral therapy (CBT): Two different psychotherapies—cognitive therapy and behavioral therapy— in one. Cognitive therapy can help you improve your mood by changing unhelpful thinking patterns. Behavioral therapy helps you identify and solve unhealthy habits. When used in conjunction with each another, these therapies have been shown to improve problems such as depression, anxiety, bipolar disorder, insomnia and eating disorders.

Heart palpitations (pal-peh-tay-shuns): The feeling that your heart is thumping, racing, flip-flopping or skipping beats. Strong emotions, caffeine, nicotine, vigorous exercise, medical conditions (such as low blood sugar or dehydration) and some medications may cause heart palpitations. Call 911 if you also have chest pain, shortness of breath or unusual sweating, or feel dizzy or faint.

Immune response: How your immune system recognizes and defends itself against bacteria, viruses, toxins and other harmful substances. A response can include anything from coughing and sneezing to an increase in white blood cells, which attack foreign substances.

Interpersonal therapy (IPT): A treatment often used for depression that lifts mood by teaching you how to relate with others in a healthier way. A therapist will help you identify troubling emotions and their triggers, express emotions in a more productive way and examine past relationships that may have contributed to your current mental health issues.

Lean protein: Meats and other protein-rich foods low in saturated fat. These include boneless skinless chicken and turkey, extra-lean ground beef, beans, fat-free yogurt, seafood, tofu, tempeh and lean cuts of red meat, such as round steaks and roasts, top loin and top sirloin. Choosing these can help control cholesterol.

Omega-3 fatty acids (oh-may-ga three fah-tee a-sids): Healthy polyunsaturated fats that the body uses to build brain-cell membranes. They’re considered essential fats because our body needs them but can’t make them on its own; we must take them in through food or supplements. A diet rich in omega-3s—found in fatty fish, like salmon, tuna and mackerel, as well as in walnuts, flaxseed and canola oil—and low in saturated fats may help protect against heart disease, stroke, cancer and inflammatory bowel disease.

Whole grains: Grains such as whole wheat, brown rice and barley still have their fiber-rich outer shell, called the bran, and inner germ. It provides vitamins, minerals and good fats. Choosing whole grain side dishes, cereals, breads and more may lower the risk for heart disease, type 2 diabetes and cancer and improve digestion, too.