In this cross-sectional study, anxiety and depression appeared in 31.1% and 36.5% of patients with hypertension, respectively. Anxiety was associated with female, secondary education or less, comorbid HLP, and lack of LPA, and the results indicated that a synergistic interaction exists between comorbid HLP and secondary education or less. Depression was associated with manual labor, comorbid HLP, and lack of LPA, and the results indicated that a synergistic interaction exists between a manual labor career and lack of LPA.
In our study, the prevalence of depression in patients with hypertension was slightly higher than the pooled prevalence of 29.8% that was previously reported in a meta-analysis using the same scale (15). This difference was mainly due to the overestimation of depression rates when analyzing patients with hypertension in a hospital setting. The pooled rate of depression in patients with hypertension in a hospital setting was higher than the rate of depression in hypertension patients in the community (27.2% vs 26.3%, however not all studies used the same assessment). The prevalence of anxiety was ranged from 8.9–55.3%, as determined by different anxiety measures (16). Differences may also result from using different threshold scores for anxiety, and different patient’s ages. However, there is no reported pooled prevalence of anxiety in patients with hypertension.
Hypertension, DM, and HLP are the three most common major chronic conditions that can lead to severe vascular events and deaths. The prevalence of concurrent hypertension and hypercholesterolemia was 6.3% in 2011–2012 and has increased significantly in the past 12 years (31). Emotional distress may occur in response to the disease manifestation, complications, progression, impact on self-image, and the need for continuous non-pharmacological and pharmacological treatment (32). People diagnosed with chronic disease can have a lower quality of life, develop somatic symptoms, and experience role impairment, all of which may lead patients to develop feelings of distress. Anxiety is a common psychological problem in the general adult population, and it is not specifically related to hypertension, as other chronic illness is also associated with an increased incidence of anxiety or severity of anxiety symptoms (33). Taking into consideration the findings of this study, we suggest that the presence of a second chronic disease, especially HLP, may affect the ability of hypertension patients to control their emotions, and can lead to an increased risk of anxiety in hypertension patients.
It is well established that LPA is a critical component of a healthy lifestyle and that it plays an important role in the prevention of chronic diseases, including hypertension and HLP (34). A high prevalence of anxiety disorder (17.0%) and depression disorder (39.1%) were found in a sample of chronic disease patients from three Southeast Asian countries, of these patients, 39.0% engaged in low physical activity (35). People with chronic conditions are more likely to have anxiety or depressive disorders than the general population and are also more likely to partake in low levels of LPA. Physical activity has benefits for physical health, as well as for the treatment of depression. In this study, insufficient LPA is one of the risk factors that increased the incidence of both anxiety and depression in patients with hypertension, which is consistent with previous studies (36, 37).
In this study, we found that patients with lower levels of education were at a higher risk for anxiety in combination with hypertension. Additional studies have also uncovered this relationship between lower education and anxiety (38). Patients with a lower level of education may find it more difficult to get adequate information to control the illness and promote a healthy lifestyle. We also found that patients with hypertension that performed manual labor were at a higher risk for depression. Manual work is typically characterized by repetitive work, manual handling and prolonged static postures, and the need to work for a long time, with insufficient time for recovery. Workers in manual jobs are more likely to suffer from musculoskeletal disorders, which are also commonly associated with depressive symptoms (39).
Our study found that working a manual job and not partaking in sufficient LPA could increase the risk of depression among patients with hypertension independently. Moreover, the two factors also had a clear interaction on depression in patients with hypertension. When patients with hypertension worked a manual job and did not partake in LPA, the risk of depression was 7.164 times that of those who worked in non-manual jobs and partook in sufficient amounts of LPA. 68.0% of the results could be attributed to the interaction between labor style and leisure-time physical activity. Whereas the health effects of LPA are considered to be beneficial, the physical activity paradox suggests there are contrasting health effects for occupational physical activity and LPA (40), which could lead to the observed synergistic effect between manual labor and lack of LPA. A previous study revealed that both male and female manual workers may be less likely to engage in LPA (41), and both physical inactivity and sedentary lifestyle appear to be significantly related to symptoms of depression (36).
Our study has several limitations. Due to the cross-sectional design of this study, we cannot conclude the causal relationship between these two risk factors and depression among patients with hypertension. Secondly, although LPA was one of the potential risk factors in our initial design, LPA measurement guidelines are not detailed enough and need further structuring.