Chronic conditions and lack of symptoms highly impact the level of adherence.  Chronic conditions such as high blood pressure, hyperlipidemia, diabetes, osteoporosis, and depression are common illnesses in which there are few or no symptoms which remind individuals to take their medication.  When patients do not perceive that their illness is chronic or requires preventative treatment, adherence is generally poor.  Adherence is generally greater for medications that provide symptom relief, as opposed to those used for treatment of a generally asymptomatic condition.