Physical and Emotional Predictors of Depression ... - SAGE Journals

Physical and Emotional Predictors of Depression After Radical Prostatectomy

American Journal of Men’s Health Volume 2 Number 2 June 2008 165-171 © 2008 Sage Publications 10.1177/1557988307312222 http://ajmh.sagepub.com hosted at http://online.sagepub.com

Bryan A. Weber, PhD, Beverly L. Roberts, PhD, Terry L. Mills, PhD, Neale R. Chumbler, PhD, and Chester B. Algood, MD Radical prostatectomy commonly results in urinary, sexual, and bowel dysfunction that bothers men and may lead to depressive symptomatology (hereafter depression) that occurs at a rate 4 times greater for men with prostate cancer than healthy counterparts. The purpose of this study was to assess depressive symptoms in men shortly after radical prostatectomy and to identify associated risk factors. Seventy-two men were interviewed 6 weeks after surgery. Measured were depression (Geriatric Depression Scale), self-efficacy (Stanford Inventory of Cancer Patient Adjustment), social support (Modified Inventory of

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arcinoma of the prostate is the leading cause of cancer in American men, accounting for 33% of all cancer cases diagnosed annually (American Cancer Society, 2007). Although cancers occur throughout the life span, according to the National Cancer Institute and the National Institute on Aging, the incidence and prevalence of prostate cancer increases with age (National Institute on Aging and National Cancer Institute, 2005; Robinson & Turner, 2003) and, indeed, prostate cancer is most prevalent after the age of 60 years (American Cancer Society, 2007). Although incidence declined for the early part of the 1990s (perhaps a rebound after an intense increase in prostate cancer awareness and screening efforts), recent estimates released by the American Cancer Society report a steady increase in overall prostate cancer incidence rates from 1995 to 2001. This rise may be due to the 40 million

From the University of Florida, Gainesville (BAW, BLR, TLM, NRC, CBA), and the VA HSR&D/RR&D Rehabilitation Outcomes Research Center, North Florida/South Georgia Veterans Health System (NRC), Gainesville, FL. Address correspondence to: Bryan A. Weber, PhD, UF College of Nursing, Box 100197, Gainesville, FL 32610-0197; e-mail: [email protected].

Socially Supportive Behaviors), physical and emotional factors (UCLA Prostate Cancer Index), and social function (SF-36 subscale). Results indicate that men with high self-efficacy and less sexual bother were 45% and 55% less likely to have depressive symptoms, respectively. Findings from this study add to the limited amount of information on the complex relationship between prostate cancer treatment and depression in men. Keywords: depression; prostate cancer; physical dysfunction and bother; radical prostatectomy; older men’s health

American men (baby boomers) reaching the age when prostate cancer emerges. Early detection and rapid advances in treatment, such as radical prostatectomy, have resulted in increased long-term survival rates as high as 99% (American Cancer Society, 2007). However, chronic treatment side effects for those undergoing surgery include urinary, bowel, and sexual dysfunction that vary in prevalence, severity, intensity, and duration, and are associated with bother, which refers to the degree of annoyance or discomfort associated with the physical dysfunction side effects. Physical dysfunction is mainly due to sphincter incompetence, altered anatomical structure, inflammation, and scar tissue from medical treatment (Dalkin, Wessells, & Cui, 2003; Resnick & Thompson, 2000). These treatment side effects cause discomfort, have social implications, and may result in a sense of shame, all of which may lower self-efficacy (i.e., the confidence in one’s ability to achieve a desired outcome) and quality of life, and increase depressive symptomatology (hereafter referred to as depression) that occurs at a rate 4 times greater for men with prostate cancer than healthy American men (Bandura, 1997; Bennett & Badger, 2005; Bhatnagar, Stewart, Huynh, Jorgensen, 165

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American Journal of Men’s Health / Vol. 2, No. 2, June 2008

& Kaplan, 2006; Korfage, Essink-Bot, Janssens, Schroder, & de Koning, 2006; Lev, 1997; Litwin, Sadetsky, Pasta, & Lubeck, 2004; Maddux & Meier, 1995; National Institute of Mental Health, 2005; Patrick et al., 2003; Stanford et al., 2000; Stevens et al., 1998). Several factors may complicate depression in this group. Men with prostate cancer are typically older men who have shrinking social networks necessary for emotional support (Arber, Davidson, & Ginn, 2003). Men with prostate cancer seem to have an aversion toward support groups that have helped other cancer patients cope with disease and treatment aftermath (Weber, Roberts, & McDougall, 2000; Weber et al., 2004). Moreover, seeking support for some men may be a sign of weakness, and discussing urinary, sexual, and bowel problems that are stigmatizing may detract from a man’s sense of masculinity and willingness to share these problems. Bandura’s self-efficacy theory (Bandura, 1997) suggests that these circumstances predispose a man to low self-efficacy that contributes to depression. Thus, the primary purpose of this study was to assess depression in men shortly after radical prostatectomy while they adjust to treatment side effects with little to no emotional support. A secondary purpose was to identify the risk factors that were predictive of depression.

Methods After institutional review board approval was obtained, 72 men, treated by radical prostatectomy, were approached during their follow-up appointment and recruited from urology clinics affiliated with large medical centers located in the midwest and southeast United States. Recruitment and data collection took place 6 weeks after surgery. This 6-week time point typically occurred within 3 months of the prostate cancer diagnosis. Inclusion criteria for the men were absence of psychiatric disorders as defined by the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV), 45 years or older, and English speaking. Only men with localized prostate cancer were eligible for radical prostatectomy and thus eligible for this study; thus, the effects of the stage of the disease on study outcomes was limited to those occurring for localized disease only. Demographic and outcome data were collected by telephone interview 6 weeks after surgery when men were most likely to experience the symptoms of unremitting urinary, sexual, and bowel dysfunction.

Outcome Measures Depressive symptoms were measured with the Geriatric Depression Scale–short form (GDS); (Yesavage et al., 1982). The 15-item instrument of depressive symptomatology discriminates between depressive symptoms and somatic complaints related to illness. The YES/NO response format is easy for participants to use, and the score is the sum of symptoms (ranging from 0 to 15), with higher scores indicating greater depression. According to the instrument’s developer (Yesavage et al., 1982), scores on the measure greater than 5 indicate the presence of depression, and this was the cut point used to determine the presence of depression in this study. In this study, the Cronbach’s alpha was .821. The validity of the GDS has been established in a wide variety of populations, including men in this study’s sample age group and ethnic characteristics (Ertan, Ertan, Kiziltan, & Uygucgil, 2005; Yesavage et al., 1982). Self-efficacy was assessed with the 38-item Stanford Inventory of Cancer Patient Adjustment (SICPA); (Telch, 1985). Items are rated on a Likerttype scale that ranges from 0 not at all confident to 10 completely confident. These ratings reflected participants’ belief in their capability in functioning with domain-specific problems related to prostate cancer that included medical treatment, communication, activity, personal management, affective state, and self-satisfaction. The ratings were summed (total scores range from 0 to 380; cut point 317), with higher scores indicating higher efficacy. In this study, the SICPA had a Cronbach’s alpha of .96. Social support was assessed using the 41-item Modified Inventory of Socially Supportive Behaviors (Krause & Markides, 1990). This inventory measured four dimensions of social support (tangible, integration, informational, and emotional). Tangible support involves offering assistance by way of monetary contribution, support in kind, labor, and time. Integration support involves the exchange for the purpose of affirmation, feedback, or social comparison. Informational support involves the provision of information to be used in coping with a stressful event or environmental problems. Emotional support involves empathy, caring, trust, and love. Study participants rated support from 0 never to 4 very often. Responses were summed (total scores range from 0 to 164; cut point 100), with higher scores indicating greater social support. In this study, the total scale had good internal consistency with a Cronbach’s alpha of .93.

Depression After Radical Prostatectomy / Weber et al.

Physical and emotional factors were assessed with the UCLA Prostate Cancer Index developed to assess outcomes in the care of men with prostate cancer (Litwin et al., 1998). The scale consists of 15 disease-related items that assess impairment in urinary, bowel, and sexual function and the extent to which these functional impairments create bother (annoyance). Respondents rated impairments by reporting frequency (1 = urinary/bowel/sexual dysfunction occurs every day to 4 = not at all), control (1 = no control to 4 = total control), and number of incontinence briefs/pads used to control leakage (1 = three or more to 4 = none). Bother was degree of annoyance that urinary, bowel, or sexual dysfunction presented, and participants rated this on a 5-point Likert-type scale. For example, participants rated dripping urine or wetting pants from 0 no problem to 4 big problem. Men may experience urinary incontinence to varying degrees; however, incontinence may be more bothersome when it interferes with sexual activity than when it interferes with daily activities when specialized undergarments can be worn. The ratings are averaged into three function and three bother subscales (ranging from 0 to 100; cut point 50), one each for urinary, sexual, and bowel dysfunction. Higher scores indicate better function and less bother. In this study, the total scale had a Cronbach’s alpha of .95, with subscales ranging from .60 for bowel function to .83 for urinary function. Social function was assessed with 2 items (social function subscale) from the widely used SF-36 measure of quality of life (Ware, Snow, Kosinski, & Gandek, 1993). The two items were rated on a 1 to 5 scale that referred to the amount of time that physical or emotional problems interfered with normal social activities. Scores were recoded according to scoring procedures to a numeric scale that ranged from 0 to 100 (cut point 50), with higher scores indicating greater social functioning.

Statistical Analysis Statistical analyses were performed using SPSS software version 13, and statistical significance was assessed at an alpha of .05. Skewed data were transformed, and those data that were not fixed by transformation were dealt with according to techniques described by Rose, Koshman, Spreng, and Sheldon (1999), and Streiner (2002). They prescribed that scatter plots be produced to identify naturally occurring cut points in the data that can then be

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dichotomized into low versus high values (e.g., low versus high bother, self-efficacy, and social function). Cut points used in this study are described below for each measure that resulted in skewed data. Bivariate analyses were used to test the association among outcome variables. Binary logistic regression was used to assess the effects of physical and emotional factors on depression while controlling for covariates (age, self-efficacy, urinary function, urinary bother, sexual function, sexual bother, bowel function, bowel bother, social function, and social support). Variables were examined to determine if they were significant between those participants with high versus low depression. Those variables that were not significant were removed from the logistic regression analysis resulting in six independent variables in the logistic regression analysis. Sample size is a complex and controversial issue in logistic regression. According to Hosmer and Lemeshow (2000), the number of participants required for logistic regression analysis can vary significantly due in part to the mixture of dichotomous and continuous variables. The general rule of thumb is that 10 participants per independent variable are needed for adequate power in logistic regression analysis (Hosmer & Lemeshow, 2000; Peduzzi, Concato, Kemper, Holford, & Feinstein, 1996; Vittinghoff & McCulloch, 2006). However, Vittinghoff and McCulloch (2006) conducted a large simulation study to test the rule of thumb. They found that significant problems occurred with confidence intervals, type I error, and relative bias with two to four events per variable. However, these problems were avoided when there were 5 to 9 events per variable and were lowest when there were 10 to 16 events per variable. Thus, the sample size in this study exceeded the recommendations of the number of participants required. Thus, having met the rule of thumb, the Wald statistic was appropriately used and odds ratios (exp(B)) were estimated for each of the independent variables in the model.

Results Sample Complete data were available on 72 men in this study. Participants ranged in age from 47 to 74 years (Mage = 60, SD = 7). Fifty-two men (72%) were White, and 33 (46%) worked full time. In this sample, 25 men (35%) had at least a high school education or technical training, 23 (32%) had some

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college education, and 24 (33%) had a 4-year degree or higher.

Table 1. Logistic Coefficient for Depression Predictors (Physical) Wald ChiSquare

Psychosocial Factors Thirteen men (18%) had high depression with a cut point of 5 or more on the Geriatric Depression Scale. Thirty-four men (47%) had low cancer selfefficacy determined by scores 317 or lower on the Stanford Inventory of Cancer Patient Adjustment, and 20 men (27%) reported low social support with scores 100 or lower on the Modified Inventory of Socially Supportive Behaviors. Sixteen men (22%) had low social function with scores 50 or lower on the SF-36 social function subscale.

Predictor Age Self-efficacy Urinary function Sexual function Bowel function Social function

Symptom Bother Fifty or lower was the cut point used on the UCLA Prostate Cancer Index to determine low versus high bother in terms of annoyance by the physical urinary, sexual, and bowel side effects of treatment. Fifty-two men (72%) reported high urinary bother, 47 men (65%) reported high sexual bother, and 16 men (22%) reported high bowel bother. When physical function outcomes were regressed on depression, men with high self-efficacy (odds ratio [OR] = –0.55, 95% confidence interval [CI95] 0.2930.884, p = .017) were 45% less likely to have depression than those with low self-efficacy (see Table 1). None of the physical function variables were significant predictors. When assessing emotional factors (see Table 2), men with high self-efficacy (OR = 0.495, CI95 0.301-0.926, p = .026) were 50% less likely to have depression. Moreover, men with less sexual bother (OR = 0.445, CI95 0.271-0.906, p = .023) were 55% less likely to have depression. Contrary to what was expected, men with less bowel bother were almost 2 times more likely to have depression, and urinary bother was not a significant predictor of depression despite the high frequency of urinary function problems.

exp(B)

.193 1.213 –.590 .555 –.180 .835 .539 1.714 .347 1.415 –.664 .515

CI95 .636 .293 .416 .128 .270 .193

– – – – – –

1.913 .884 3.929 2.267 6.388 2.062

0.503 4.726* 0.406 2.377 1.012 3.851

CI95 = 95% confidence interval. *p < .05.

Table 2. Logistic Coefficient for Depression Predictors (Emotional)

Physical Factors Fifty or lower was the cut point used on the UCLA Prostate Cancer Index to determine good versus poor physical function in the areas of urinary, sexual, and bowel function. Sixty-seven men (93%) had poor sexual function, 48 men (66%) had poor urinary function, and 9 men (13%) had poor bowel function.

B

Predictor Age Self-efficacy Urinary bother Sexual bother Bowel bother Social function

B .506 –.704 .315 –.810 .691 –1.050

exp(B) 1.659 0.495 1.370 0.445 1.995 0.350

Wald ChiSquare

CI95 .722 .301 .562 .271 .902 .224

– – – – – –

2.542 .926 1.910 .906 2.694 2.647

2.375 4.676* 0.896 5.948* 4.521* 6.336*

CI95 = 95% confidence interval. *p < .05.

Discussion The incidence of depression is higher in men after radical prostatectomy than in healthy men (Bandura, 1997; Maddux & Meier, 1995). This may in part be due to how depression is measured (Heisel, Flett, Duberstein, & Lyness, 2005). In this study, nearly one in five men had high depression (Brink et al., 1982; Sheikh & Yesavage, 1986; Yesavage et al., 1982). Several factors contribute to depression in this age group of men including small social networks to whom men can turn for emotional support, the stigma of urinary, sexual, and bowel side effects of treatment and the social isolation associated with these factors, and low prostate cancer self-efficacy (Arber et al., 2003; Bandura, 1997; Weber et al., 2004). This study assessed these factors and determined social function and self-efficacy significantly predicted depression, but the effect of urinary, sexual, and bowel dysfunction and the associated bother did not.


Urinary and sexual dysfunctions associated with prostate cancer treatment have a complex relationship with depression (“Depression and Erectile Dysfunction,” 2004; Korfage et al., 2005; Steers & Lee, 2001; Sugimori et al., 2005; Underwood, 2006; Watson, Currie, Curran, & Jarvis, 2000; Wong, Chan, Hong, Leung, & Woo, 2006). However, the vast majority of men with prostate cancer are older and urinary and sexual symptoms may not be new experiences due to chronic comorbid conditions. For these men, adapting to prostate cancer treatment side effects may be rapid or not even an issue depending on prior physical functioning. Additionally, sexual dysfunction is far more prevalent after radical prostatectomy than urinary or bowel dysfunction, but it is not as bothersome. This may be related to men dealing with urinary incontinence on a daily basis, whereas sexual dysfunction may not occur even daily. In the past, urinary incontinence resulted in embarrassment from foul odor, dampness of clothing, and clothing bulkiness associated with wearing incontinence pads. However, great strides have been made in incontinence protection and commercial advertising has normalized incontinence, thus reducing the social stigma associated with it. These physical side effects of treatment may not be the best predictors of depression at this time, and other more reliable factors such as selfefficacy and social function should be considered. As suggested by Bandura’s self-efficacy theory (Bandura, 1997), men who are challenged by unfamiliar situations, such as the side effects of radical prostatectomy, will have decreased confidence in their ability to achieve desired outcomes in prostate cancer survivorship. Those men with a low sense of confidence are less likely to attempt activities and behaviors required of the situations in which they find themselves, and this could lead to depression (Maddux & Meier, 1995). Thus, self-efficacy that was a predictor of depression in this study may be an important factor for early screening. Moreover, interventions designed to enhance self-efficacy during treatment recovery and cancer survivorship are important. Results from this study point toward the role that decreased social functioning plays in depression because those with low social functioning had greater depression than those who had high social functioning. This may be the result of several factors including a man’s stoic desire to “go it alone” after radical prostatectomy; a limited number and availability of those in which he can confide his concerns about his frustration and embarrassment over urinary, sexual, and bowel dysfunction; and conversely, his concern

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that discussion with family and friends may lead to embarrassment and shame over urinary, sexual, and bowel dysfunction (Hedestig, Sandman, Tomic, & Widmark, 2005; Weber et al., 2004). Inasmuch as physical dysfunction was not a predictor of depression in this study, it may be the emotional reaction to the physical dysfunction that contributes to depression the most.

Limitations and Implications The small sample size limits generalizability of the findings. Self-efficacy is domain specific, and the assessment of self-efficacy with the Stanford Inventory of Cancer Patient Adjustment may not have adequately assessed the urinary, sexual, and bowel symptoms in men in this study. The measure was not specific to prostate cancer and did not address the effect of urinary and bowel dysfunction on self-efficacy. Moreover, only one item was used to assess self-efficacy associated with sexual dysfunction but the complexity of the concept requires that it be assessed in more than one way. The majority of men in this sample had low depression that may have reduced the predictability of physical and emotional factors. Future research should include a sample with greater heterogeneity that better approximates the incidence of depression in the population of men with prostate cancer. This study adds to the limited amount of scientific information on predictors of depression in men after radical prostatectomy. Additional research is needed to assess the effects of shame, embarrassment, and stigma associated with the physical dysfunction that side effects of radical prostatectomy have on depression in these men. In light of this study’s findings that prostate cancer and its treatment challenge a man’s confidence in meeting associated challenges, reliable measures of prostate cancer–specific self-efficacy are needed that accurately assess a man’s confidence in meeting the challenges of the disease and its treatment. Thus, the Stanford Inventory of Cancer Patient Adjustment that was used in this study could be tailored to assess self-efficacy for circumstances unique to this population (e.g., urinary, sexual, and bowel dysfunction). Clinicians can begin to base their practice on this evidence in support of comprehensive screening, discharge, and follow-up planning. It is important to determine who is at greatest risk for low social functioning and low self-efficacy that appears to contribute to depressive symptoms after radical prostatectomy.

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Thus, assessment should include discussion of activities and social function prior to and after prostate cancer and its treatment. Informed with this information, health care providers can develop personalized interventions for the management of urinary incontinence that may interfere with social, work, or leisure activities such as visiting with friends, travel, or playing golf, among others. Because men are not likely to be aware of available incontinence management products, samples of adult briefs, pads, penile clamps, and condom catheters can be demonstrated and provided. Furthermore, suggestions can be made for controlling urinary incontinence odor such as increasing water intake to reduce urine concentration, use of a perineal skin cleansing agent/deodorizer, or altering diet to avoid foods that produce foul-smelling urine, such as asparagus. Thus, men can continue social, work, and leisure activities at or near the same level as they enjoyed prior to diagnosis and treatment for prostate cancer. Finally, it is important to assess alterations to physical function after treatment for prostate cancer. Discussions can then focus on available options that facilitate the return of partial or total physical function. Included should be providing samples of medications or educational materials and frank discussion on therapeutic devices such as vacuum pumps and penile prostheses.

Acknowledgments Funding support provided by the National Cancer Institute (R03CA96204). Also, this material is the result of work supported with resources and the use of facilities at the VA HSR&D/RR&D Rehabilitation Outcomes Research Center.

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