Comorbidity between depressive symptoms and substance use in-patients hospitalized for non-psychiatric diseases

Epidemiological studies have shown a high prevalence and concurrence between depression and substance use. This is known as "dual diagnosis" and is associated with a worse prognosis for patients.

To establish the comorbidity between depressive symptoms and substance abuse in patients admitted with acute or chronic diseases to a public hospital.

A descriptive, cross-sectional study of prevalence which included 296 patients aged 18-65, to whom the PHQ-9 and ASSIST 3.0 scales were applied to determine the prevalence of depressive symptoms and substance abuse. Other clinical and sociodemographic variables were also taken into account.

50.7% were women with a median age of 41 and an interquartile range of 27 years. Moderate-to-severe depressive symptoms were found in 27.4% of the patients. Alcohol was the substance with the highest consumption in the previous 3 months with 53.7%, followed by cigarettes (47.6%), marijuana (26.7%) and cocaine (14.5%). A significant association was found between severe depressive symptoms PHQ-9 ≥ 20 and problematic use of alcohol, marijuana and cocaine (ASSIST score >26); alcohol (RP 27.30, 95% CI [2.37-314.16], P = 0.01); marijuana (RP 15.00, 95% CI [3.46-64.96], P = 0.001) and cocaine (RP 10.65, 95% CI [2.23-51.10], P = 0.01).

A high prevalence of depressive symptoms and substance use was found in patients hospitalised for non-psychiatric medical conditions, which worsens the prognosis of the underlying medical condition.

To provide better hospital care for patients, we need to give visibility to the problem of dual pathology. This could be achieved by conducting more related research in these clinical scenarios.