Hi Depression is a medical disorder which is caused by certain neuro chemical changes in the brain. These changes affect our mood, behavior and thought process. Symptoms of depression are feeling sad most of the time, irritability, anxiety, lack of interest in things that you liked doing before, feeling hopeless and worthless, lack of energy and focus, disturbed sleep and appetite. In severe depression, people may have thoughts of harming themselves. Depression can remain undiagnosed for years. Depression is a treatable medical condition and can be effectively treated with medications and psychological therapy. Hope this helps. Feel free to contact me for further help. Thanks Regards Dr Ankita Mishra

Symptoms of depression vary from person to person a basic few would include sadness of mood for a major duration of the day, decreased interest in daily activities,  social withdrawal, negative thoughts or thoughts about suicide, feeling of helplessness worthlessness hopelessness, somatic complaints, sleep disturbances, irritability, etc etc. The cause can be genetic, psychological, or trauma induced, or sometimes without any reason. The diagnosis is done by a psychiatrist thru interview. And yes due to the stigma and not considering mental disorders as actual diseases can cause it to go undetected for years or maybe after death when the person commits suicide. Thats why its important to talk and visit a psychiatrist personally. Yes it can develop and get worsened over the years. Visit a psychiatrist personally for more queries.