When people experience intense sadness for a long period of time is known as major depressive disorder.
Step-by-step explanation:
Sadness is a natural feeling that occurs when a loved one passes away or when a person is sick or something bad happens but if this sadness linger for a long period of time major depressive disorder takes place.
Symptoms that shows that you are suffering from major depressive disorder are as follows, the doctor will ask you certain question that whether the person feel sad most of the time in a day, whether the person is interested in various activities or not, whether the person is losing weight or not, whether the person is unable to sleep or not.
Factors that influence MDD are as follows, due to consumption of alcohol or drugs,if the person is suffering from cancer, if person is taking certain medicine or steroids.