Knowing the risk factors of developing any particular disease helps to understand the odds of developing that disease. It is important, however, to remember that odds, no matter how favorable or unfavorable, are still just odds with the outcome for any particular event still unknown. Although the odds of developing lung cancer may be greater for one who smokes a pack of cigarettes a day than for one who does not, that does not guarantee any particular outcome for either individual.
There are risk factors that one can change and risk factors that one cannot. Risk factors that can be changed are commonly referred to as modifiable. One cannot modify the genes inherited from one’s parents, but one can use the knowledge of one’s family history to help make choices in life to reduce other risk factors contributing to the probability of developing a particular disease. Thus recommendations for various diagnostic tests for breast cancer, colon cancer, and heart disease vary depending on whether someone has a family his-tory for a particular condition. With that in mind, the risk factors for depression are as follows:
- Gender: Depression is two times more likely in females.
- Age: The peak age at onset is 20 to 40 years.
- Family history: A person has a one and a half to three times higher risk when he or she has a positive family history for mood disorders.
- Marital status: Separated and divorced persons report higher rates. Married males have lower rates than unmarried males, and married females have higher rates than unmarried females.
- Postpartum : There is an increased risk for the 6-month period after childbirth.
- Negative life events: A possible association exists. Early parental death: A possible association exists.
- Premorbid personality factors: A possible association exists.
- Comorbid psychiatric illnesses: A clear association exists.
- Comorbid medical illnesses, particularly cardiac disease: A clear association exists.
- Substance abuse or alcoholism history: A clear association exists.
- Socioeconomic status: A possible association exists.
- Sedentary lifestyle: A possible association exists.
- Childhood conduct and behavior problems: There is a 20% increase at the age of 21 years.
There are several risk factors of developing recurrent depression:
- Multiple prior episodes
- Incomplete recoveries from prior episodes
- A severe episode
- A chronic episode
- Bipolar or psychotic features
In depression, the risk factors that one can modify are very limited when compared with diseases such as heart disease; with heart disease one has opportunities for lowering cholesterol, blood pressure, and weight through various options, such as diet, exercise, smoking cessation, and prescription medications. It is often difficult, if not impossible, to change exposure to any of the risk factors for depression mentioned previously here, except for substance abuse and alcoholism, and yet the perceived level of control over developing depression is much greater than other diseases, another paradox of mental illness! Regarding the risk of recurrence, some control over risk factors can be taken by ensuring aggressive treatment with a competent clinician or team of clinicians and sticking to the treatment plan, with frequent follow-up visits to ensure that the symptoms are controlled effectively with all available therapies.