Prevalence and Risk Factors of Depression in Geriatric Patients with Dermatological Diseases

Although usually not a life-threatening condition, a skin disease can contribute to various degrees of psychosocial impairment and alter a patient's quality of life1-3. Many patients with skin disease are significantly distressed because the disease affects visible parts of the body4, 5 and/or because it causes intractable symptoms such as itching or pain. Some review articles suggest that depression is one of the most common psychological co-morbidity in patients with dermatologic disorders6-8.

In general, depression is a relatively common disorder in older patients, and often occurs in the context of a physical impairment9. In a study by Watkins et al.10, the severity of depression correlated significantly with that of medical comorbity. Likewise, depression adversely influences the outcome of comorbid health disorders in the elderly11. According to a large number of studies on the psychosocial impact of neurological and medical illnesses, increased rates of depression were found to be associated with conditions such as cardiovascular disease10, 12, stroke13, 14, Alzheimer's disease15, and Parkinsons disease16. However, little has been reported on the association between depression and dermatologic diseases in the geriatric population. Therefore, we have conducted a survey to investigate the hypothesis that geriatric patients with dermatological disease are at an increased risk for depression in Korea. We have also sought for non-dermatologic variables that might predict depression.

Psoriasis and vitiligo have long been recognized to be associated with potentially adverse effects on mental health. In addition, there has been studies that evaluated psychological influences of dematologic diseases on the issue of quality of life, measured with the Dermatology Life Quality Index21-23. The differences in study methodology (e.g., differences in patient recruitment and population characteristics) on depression and skin disease make a direct comparison among these studies difficult, but patients with psoriasis were found to be at an increased risk of depression. Kurd et al.24 reported that the adjusted hazard ratio for receiving a diagnosis of depression in patients with psoriasis, when compared with the respective control population, was 1.31 (95% confidence interval, 1.37~1.41).

To our knowledge, the analysis of a specific relationship between dermatological diseases and depression in the elderly population has not been previously reported. In our study, mild to severe depression was observed in 62.3% of patients. This is in agreement with a study by Esposito et al.25, which investigated the prevalence of depression in patients with whole age group with psoriasis and found 62% of patients to demonstrate depressive symptoms.

Although the prevalence of depression in our geriatric population with dermatological conditions was significantly higher than that of the general population, we have made some interesting observations. In the elderly population, it is well known that sociodemographic correlates of depression include female gender, divorced or separated marital status, low income and/or educational level, inadequate social support, and recent undesirable and unexpected life events26, 27. In this study, lower education level was indeed a risk factor for depression, although we were not able to identify other sociodemographic variables that independently predicted depression.

In a study of Korean geriatric population, Lee et al.28 reported that depression in the elderly was not associated with sociodemographic variables but, rather, was related to the presence of physical illness, stressful life events, and cognitive dysfunction. In other studies investigating the psychosocial burden of psoriasis and vitiligo, disease severity, disease extent, and visibility of the lesions were strong predictors of the psychological impairment22, 24, 29. The multiple regression analysis in this present study, however, found no significant differences between depressive and non-depressive groups when considering medical-history variables such as diagnosis, disease category, and disease duration.

The recruitment method of patients from our dermatological department was not without its limitations. Despite the high response rates, our patients may not represent the entire geriatric population with dermatologic conditions. First, the sample size was not large. Second, as a tertiary referral center, our clinic is visited by a greater number of patients with severe and/or intractable diseases than the norm, and this may have contributed to an over-representation of dermatologic patients under increased psychological burden. However, the analysis of disease categories in our study closely resembles known clinical pattern of skin diseases in the general geriatric population30, 31. This implies that our sampling could be considered representative of the general distribution of geriatric dermatological conditions. From this perspective, the potential selection bias appears to be minimal in this study.

Another limitation of the study design was in the self-administered nature of the survey. In contrast to questions of objective nature (i.e. demographic information such as age and gender), questions concerning disease characteristics were inherently liable to subjective interpretations and to potential misinterpretation by the patient. With the elderly population growing worldwide, geriatric depression is a major health concern that can be life threatening if not recognized in time and properly managed. This is a disease that significantly reduces quality of life and also is the single most important predictor of suicide27. In particular, physical health has a major impact on a person's mood and well-being, and geriatric skin disorders often represent a symptom or complication of an underlying systemic disease. According to Koenig and Blazer26, the rate of major depressive disorder in the hospitalized elderly patients is over 10 times the rate reported for the general population. In univariate analysis, our results were consistent with such studies in showing that physical health and certain systemic diseases correlated significantly with a higher GDS score. The concurrent disease included allergic rhinitis, angina, arrhythmia, asthma, benign prostate hyperplasia, cerebral vascular accident, congestive heart failure, dementia, dyslipidemia, gastritis, gastroesophageal reflux disease, gout, herniated nucleus pulposus, osteoarthritis, osteoporosis, rheumatoid arthritis, thyroid disease, tuberculosis, and varicose veins.

In the presence of a skin disorder, patients experience physiological changes that are induced by the mental stress, and these two factors feed each other in a vicious cycle. Most skin diseases in the elderly are chronic and recurring and incurs higher healthcare utilization costs. As a consequence, these patients may suffer from an increased rate of depression secondary to the psychological impact of the ongoing, long-term treatment. Thus, accurate and early diagnosis of depression is important because depression is a substantial morbidity which can be ameliorated with a variety of pharmacological and nonpharmacological interventions32, 33.

In conclusion, geriatric patients with dermatological diseases are at an increased risk of depression. The results of this study should draw the attention of any physician who manages elderly patients with dermatologic diseases, as appropriate screening for depression and provision of emotional support are likely to improve the prognosis for the patient. Further investigation into the relationship of dermatologic diseases and depression in the elderly should determine the mechanisms by which dermatological disease is associated with higher rates of depression as well as approaches to prevent adverse psychological outcomes in the elderly with skin disorders.

In this preliminary study, we did not actively manage the psychological aspects of those patients with high GDS scores. It is possible that more active interventions, such as antidepressants prescription and psychosocial support, would reduce stress and depression32, 33 and subsequently improve the prognosis of skin disease. Considering the increased rate of depression in this population, we hope to test the hypothesis above by performing an active psychological intervention in a future study.