The basic connection between obsessive-compulsive disorder (OCD) and anxiety is that both are classified as anxiety disorders. In most people, uncomfortable sensations like nervousness, tenseness or dread pass after a certain amount of time. For people with anxiety disorders, these feelings become persistent and can make social situations or everyday tasks difficult. In people who suffer from OCD, thoughts that most people wouldn't linger over, like a fear of germs, become habitual and debilitating. OCD and anxiety are similar in that anxiety-creating thoughts become persistent and cause excessive worry or compulsive behavior.
Anxiety disorder is an umbrella term that includes panic disorder, in which panic attacks occur, and phobias. "Anxiety" usually refers to generalized anxiety disorder. People who suffer from generalized anxiety disorder might worry excessively about the health of their heart, their breathing, or their kids' safety, for example. Concentration can become difficult, the muscles become tense, and difficulty sleeping might occur, among other things.
OCD refers to obsessive thoughts and compulsive actions. Examples of obsessive thoughts include checking and rechecking whether the stove is off, if the door is locked, or whether one's hands are clean enough. Sufferers develop compulsive behaviors like excessive hand-washing, and rituals like checking door locks over and over.
Because OCD and anxiety both occur on the anxiety disorder spectrum or scale, different ideas have arisen to explain them at the same time. Early pscyhoanalysts looked for the source of OCD and anxiety in childhood experiences. Today, psychologists tend to explain OCD and anxiety by one of two views, or a combination. Those views are that OCD and anxiety arise from either a biological origin, usually in the brain, or by a learning mechanism that reinforces anxiety-causing thoughts.
Those who support the learning method suppose that increased attention to anxious thoughts also raises the attention people pay to anxiety-inducing events. For example, someone who thinks of all the bad things that could happen in a social situation before it happens, and then broods on the event after it is over, could be more likely to develop social anxiety. Similarly, repeatedly thinking of the diseases germs can cause, and then washing one's hands to relieve the stress, is likely to reinforce both the thoughts and the behavior. Others look for the role certain parts of the brain and brain chemicals play in OCD and anxiety.
Treatment of OCD and anxiety is somewhat similar. Drugs may be prescribed; some anti-depressants can help people suffering from either disorder. Cognitive-behavioral therapy, useful for both disorders, is intended to help sufferers change their thoughts and attitudes without focusing too much on the cause. It basically consists of helping people with OCD and anxiety learn to control their responses to stressful thoughts, which allows them more freedom in their actions.