In this study, the overall depression risk score, as well as several individual subscores, were higher among participants with diabetes and an ulcer than among participants with diabetes and a foot at risk for ulceration. The severity of the symptoms of depression increased the chance of presence of ulceration by a factor of six, indicating an association between depression and ulceration, as observed in previous studies.3-6
Additionally, gender was identified as a risk factor for ulceration. Several studies indicate a higher prevalence of lower limb complications in male patients. A prospective population-based study15 involving 279 persons with diabetes and 577 controls identified an association between diabetic neuropathy and male gender. A prospective study16 with 132 patients with diabetes showed the prevalence of foot lesions was higher in men. In a prospective study17 conducted among 2,610 patients with type 2 diabetes, researchers documented a higher rate of diabetic neuropathy in male patients. A recent retrospective study4 among 496 patients also showed that male gender was a significant predictor for ulceration.
Williams et al6 demonstrated patients with type 2 diabetes and depression present a risk two times higher for having a foot ulcer than persons with diabetes who are not depressed. Winkley et al18 showed depressive disorder in patients with their first diabetic foot ulcer was associated with a mortality risk two times higher than in patients who were not depressed. Contrary to previously published research,6-18 the current study showed a significant difference in depression scores between patients with diabetes and an ulcer when compared to patients with foot at risk.
A systematic review19 showed some factors seem to be correlated to depression in patients with diabetes: difficulty of acceptance and adaptation to the disease and dealing with the changes imposed on routines of daily life. The functional limitations and other effects of foot problems in persons with diabetes would result in even more lifestyle changes. The occurrence of ulcers in the diabetic foot can have a considerable psychological impact on these patients’ lives. A cross-sectional study20 involving 14 patients with diabetic foot versus a control group with 24 diabetic patients without any foot problems identified a large impact on physical role, physical functioning, and mobility scores among patients with an ulcer. A qualitative study21 of 47 patients with a diabetic foot showed the presence of four psychological conditions: living a restricted life, existing in social isolation, experiencing discredited definitions of self, and becoming a burden. In the current study, analysis of the BDI items also provides some understanding about the symptoms associated with depression in these patients.
Depressive symptoms in patients with clinical comorbidity, such as diabetes mellitus, are common. In a recent systematic review of 31 studies,22 depression was associated with chronic diseases such as diabetes, congestive heart failure, coronary artery disease, osteoarthritis, arthritis rheumatoid, asthma, and chronic obstructive pulmonary disease. At times, somatic symptoms are confused with those of the disease itself, making it useful to differentiate the symptomatic pattern of depression from the characteristics of the disease causing the depression.13,23,24 In this study, somatic complaints such as appetite loss and weight loss were more common in patients with foot ulcers and can be attributed to the underlying disease, medication use, treatment, or complications from diabetes.
Some cognitive-affective symptoms noted in the BDI scale were relevant to the group of patients with an ulcer, such as social isolation, punishment feelings, self-accusation, and pessimism. Because ulcers frequently are associated with pain, mobility restrictions, and decreased independence, along with unpleasant appearance and odor that can contribute to refraining from social interaction, social isolation is a risk. In a cross-sectional study25 of 50 patients with diabetes and foot ulcers, 64% had symptoms of moderate depression — predominantly, sadness, distorted body image, self-depreciation, decreased libido, and social isolation. Cordova and Scott26 presented a conceptualization of intimacy as a behavioral phenomenon from a theoretical study; they noted that by constantly avoiding social contexts, an individual will have fewer chances to experience positive reinforcement (attention, approval, manifestations of fondness and tenderness), further diminishing his repertoire of social skills.
The current study results suggest some aspects deserve special attention. The feeling of punishment can surface due to the loss of positive reinforcement that occurs when the patient with an ulcer has to abandon activities considered enjoyable at the same time he/she is told to implement activities potentially seen as disagreeable or unpleasant. These situations can be perceived by the patients as damage, loss, or punishment. The feeling of self-accusation also can emerge in this context because in any given moment, the failure to practice foot self-care behavior can trigger a negative consequence such as ulceration and/or amputation.
A cross-sectional study27 of 316 patients with diabetes yielded the hypothesis that individuals with the disease could be more pessimistic than their counterparts without diabetes mellitus, leading to feelings of hopelessness toward the future, including their own health. This lack of confidence, associated with the difficulty in confronting adverse situations, contributes to these individuals’ renouncing the pursuit of their objectives, overlooking treatment, and consequently fostering the potential development of the complications of diabetes.
The current study found patients with severe depression were six times more likely to present with an ulcer as patients with minimal scores of depression in accordance with the findings of Williams et al,6 who described depression as a risk factor that increased the chance of ulceration.
The rates of ulceration and amputation in patients with diabetic foot suggest the complications frequently occur because of lack of self-care effectiveness and of involvement in high-risk activities.7 However, this lack of self-care was not noted in the current study, because patients, whether at risk for or who already had a foot ulcer, reported adequate foot self-care.
The high rate of adequate self-care behavior documented in this study may be specific to this study population, because all receive on-going education about self-care practices. Bell et al10 showed patients with diabetes who received education for foot care are more encouraged to practice the necessary self-care behaviors.
Inadequate self-care is frequently associated with the presence of depression. A prospective study28 evaluated depression symptoms and healthcare in 168 patients with type 2 diabetes and found elevated levels of depression were associated with poor participation in education programs, inadequate diet, and poor medication. A prospective study29 of 208 patients with type 2 diabetes showed the negative influence of depression over self-care practices such as diet, physical exercise, and foot care. The current study found no evidence of this association; patients with an ulcer, despite evidence of depressive symptoms, performed adequate self-care.
Gonzalez et al29 first published that depressive symptoms predicted nonadherence to self-care among patients with type 2 diabetes, but subsequently found the association between depression and ulceration was independent of the occurrence of self-care,5 underscoring the controversial nature of this issue. On the other hand, such findings strengthen the need for diabetic foot ulcer management within a context that takes into consideration not only physiopathological, but also psychosocial and behavioral aspects.
One of the strong points of the current study is the comparison of depression and self-care between patients at risk for and patients who already had a foot ulcer. Both groups were affected by the lower extremity complications of diabetes, such as alterations in protective sensibility and associated plantar callus and foot deformities such as hammertoes and claw toes.