Screening for Depression using the PHQ-9 questionnaire: a study for Tunisian individuals consulting in the primary health care centers.

Introduction: Depression is considered a global public health problem especially in the developed countries, where depression is the leading cause of morbidity.

Objectives: To determine the point prevalence and the severity of depression in primary health care, to define the profile of patients suffering from depression and consulting in primary health care. To identify risk factors for depression, in particular chronic co-morbid conditions.

Methods: Our study was a descriptive and analytical cross-sectional study of 1000 patients aged over 18 years consulting in ten primary care structures. It took place during a period of six successive days from 8 to 13 April 2012. Depression was assessed by the 9-item-Patient Health Questionnaire (PHQ-9).

Results: In our sample, the average age was 42,4 years ranging from 18 to 89 years. Females were predominant with 66,6 %. According to the PHQ-9, the prevalence of major depressive episode (MDE) was 12,1 %. It was higher among women (13,5%) compared with men (9,3%) with an odds ratio of 1,5. The highest prevalence of MDE (19%) was noted in the age group of 45-54 years. The most prevalent clinical signs found in our population were sleep disorders (29,7%) and suicidal ideation (28,4%). Among patients with MDE, only 10% were followed up for depression. Major depressive disorder was significantly associated with comorbid chronic diseases (p < 0,001), especially diabetes (p = 0,043, OR = 2,1), musculoskeletal diseases (p = 0,028, OR = 2,1) and pulmonary diseases (p = 0,001 , OR = 5,5). Having one comorbid chronic condition multiplied the risk of having a MDE by 2,2. This risk was 3,2 for two or more comorbid chronic conditions.

Conclusion: Depression in primary care remains a largely underdiagnosed and undertreated condition. Patients with chronic disorders are particularly vulnerable.