Recognition of depression in patients who smoke

Depression is a common illness in family practice and is frequently missed by busy practitioners. Recent studies have suggested a relationship between smoking and depression in the general population. The purpose of this study is to determine whether a patient's smoking is related to the physician's recognition of a patient's depression. If so, smoking may serve as a cue used by physicians to recognize depression in their clinical decision-making process.

Adult patients presenting to the University of Oklahoma Family Practice Residency Clinic were screened for depression using the short form of the Beck Depression Inventory (BDI). After each patient visit, upper level residents or fellows completed response cards on which they recorded their assessment of the likelihood of a depression, their familiarity with the patient, and whether they had any knowledge of a depression history.

The prevalence of depression as measured by the BDI among smokers (n = 232) and nonsmokers (n = 472) was 24.1% and 15.3%, respectively, a significant difference (P less than .001). Physicians identified depression at a significantly higher rate (75.0%) among depressed smokers than among depressed nonsmokers (48.6%) (P less than .0001). Smokers were 2.06 times as likely to be labeled depressed when controlling for the presence of a current depression, physician knowledge of a depression history, and physician familiarity with the patient (P less than .0001, 95% CI = 1.44,2.94).

Smoking may serve as a cue for the clinician in the recognition of depression. Further research is needed to determine how smoking or a related factor may be used by physicians to correctly identify depression.