Prevalence of comorbid depression and obesity in general practice

I read with great interest the article by Carey et al.¹ As a co-tutor of the master thesis related to a similar topic,² I would like to respond even at this late stage.

A cross-sectional study was carried out among 56 primary care patients, mean age 48.71 years ±10.78, 24 overweight women (BMI 25–<30 kg/m²) and 32 obese women (BMI ≤30 kg/m²), in the city of Niš (south east part of Serbia). The Patient Health Questionnaire (PHQ-9) was used to assess depression.³ A score of ≥10 on a 27-point scale was used to define clinically-relevant depressive symptoms. Body weight and height were measured to the nearest 0.1 kg and 0.1 cm, respectively, by using standardised equipment and body mass index (BMI) was calculated as weight (kg) divided by the square of height (m²).

The prevalence of depression in our study was similar among overweight and obese participants (48.4% and 51.6% respectively) and significantly higher compared to the prevalence of depression in the general population (between 16% and 34%). However, for only one-sixth (between 12% and 16%) of the participants, a diagnosis of depression has been confirmed. The most common symptoms of depression were overeating (74.6%) and loss of energy (69.3%). The average PHQ-9 score was 9.967 ± 4.79, represented mild form of depression. Univariate logistic regression analysis identified the duration of obesity as a risk factor for depression and every year duration of obesity increased the risk of depression for 7.7%.

We have to bear in mind the current social circumstances that have a strong influence on the prevalence of mental disease in the countries in transition. For example, depression is the leading cause of non-fatal disease burden in Serbia. In addition, mental illness is associated with stigma in these countries, so the symptoms of depression may often be overlooked and go untreated in the GP’s practice.

To conclude, PHQ-9 is a really useful screening tool for depression for all obese patients attending ambulatory care. Further studies should focus on various socioeconomic and cultural environments and barriers.