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Psychosocial Factors and Surgical Outcomes: An Evidence-Based Literature Review

Rosenberger, Patricia H. PhD; Jokl, Peter MD; Ickovics, Jeannette PhD

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Journal of the American Academy of Orthopaedic Surgeons: July 2006 - Volume 14 - Issue 7 - p 397-405
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Abstract

More than 42 million inpatient surgical procedures are performed in the United States annually, including more than 1 million orthopaedic procedures.1 As less invasive procedures have been developed and refined, the rate of ambulatory procedures has risen dramatically, replacing inpatient procedures.2 Additionally, patient expectations regarding surgical outcome have changed. Patients now expect quicker, less painful, and more complete recovery.

As surgical procedures have been developed and refined and have become commonplace, determining which factors predict rapid and successful surgical outcome has become a priority. Patient demographic factors (eg, sex, age) and clinical factors (eg, the nature and extent of injury), specific anatomic structures damaged, and the presence of comorbid health conditions have a demonstrated influence on surgical recovery time and return to full function.3–6 Even when these factors are taken into account, however, substantial variability exists in postoperative recovery time. For example, orthopaedic studies report that between 47% and 70% of patients with “successful” anterior cruciate ligament (ACL) reconstruction return to all sports activities at 4 years or later postoperatively.7,8 With most surgical procedures, a certain percentage of patients do not fully recover to their preinjury and/or presurgical condition, and no specific explanation, such as surgical complications or comorbid conditions, is found to limit the extent of recovery. Identifying factors that account for this source of variability is an important area of investigation.

Recently, psychosocial factors—the combination and interplay of psychological and social factors that potentially influence health, injury, illness, and disease—have been included in outcomes research. Significant psychosocial influences on surgical outcomes have been found with procedures such as knee arthroscopy,9,10 ACL reconstruction,11 knee replacement,12 hip fracture repair,13 and spine surgery.14 Recent reviews indicate that depression and anxiety are associated with worse outcomes following coronary artery bypass grafting surgery15 and that preoperative anxiety is associated with postoperative pain.15,16 However, Salmon17 noted that psychosocial factors (eg, distress) generally do not correlate strongly with indices of surgical outcomes (eg, analgesic use, length of hospital stay). Munafo and Stevenson16 reported that the relationship between anxiety and postoperative physical measures of recovery remains “unclear.”

The apparent inconsistency of results across surgical outcomes studies may be partially explained by the diversity of studies across a variety of research disciplines. The literature investigating the psychosocial influences of surgical outcome is characterized by differences in (1) psychosocial variables, (2) patient groups, (3) surgical procedures, and (4) outcome variables. The variety and heterogeneity across studies is inevitable given that specific medical problems requiring specific surgical procedures necessarily dictate certain clinical indices of recovery.

Although equivocal, the association between psychosocial factors and surgical recovery has demonstrated empirical support. A practical question remains, however: do psychosocial factors add predictive power when determining surgical outcomes, even after patient demographic and clinical factors have been considered? In other words, are psychosocial factors clinically important in that they contribute to the surgeon's understanding of the likelihood of a rapid and complete recovery, above and beyond the information already gained by reviewing patient and clinical factors?

Our primary objective in this systematic review was to determine whether psychosocial factors demonstrate effectiveness in predicting surgical recovery while controlling for clinical factors that already demonstrate predictive significance. We systematically reviewed the results of surgical outcomes studies published between 1990 and 2004. We reviewed studies that used specific statistical techniques across multiple types of surgical outcomes to clarify the role of psychosocial factors in the recovery process. Specifically, we sought to identify whether psychosocial factors influence physical outcomes across diverse surgical procedures and whether specific psychosocial factors emerge as strong predictors of outcome.

Overview of Studies Included in the Review

A search of MEDLINE and Psyc-INFO databases for surgical outcomes studies generated more than 1,000 citations, from which we selected articles that investigated the influence of psychosocial factors on a variety of objective clinical outcomes. The psychosocial factors were grouped into five general categories: mood, attitude, social support, coping mechanisms, and personality factors. The influence of these five categories of psychosocial factors were examined based on five types of surgical outcome: (1) pain and analgesic use, (2) surgical procedure and complications (eg, need for anesthesia, nausea, vomiting, physical complications), (3) length of hospital stay, (4) functional recovery (ie, ambulation, activities of daily living, return to work, return to social functioning), and (5) clinical and selfreport ratings of physical recovery (eg, clinical summary score, including several components of outcome; rating scale of physical complaints). These categories reflect common surgical outcomes across diverse surgical procedures and are relevant to orthopaedic procedures. Studies investigating outcomes such as postoperative quality of life and psychological adjustment were not included.

In addition, the search was restricted to studies using regression analytic techniques that included both psychosocial variables and relevant clinical variables as covariates in the analyses. Rather than simply demonstrating the presence of a relationship, this analytic strategy determines whether psychosocial factors have an influence on surgical outcomes beyond, or more powerful than, the influence already accounted for by clinical factors, such as comorbidity or disease severity. Only psychosocial factors demonstrating significance values of P < 0.05 in the regressional analyses were considered significant predictors of outcome and are reported herein.

Because surgical outcomes studies using this rigorous statistical approach were limited, the search was not restricted to orthopaedic outcomes studies. No surgical outcomes studies using child or adolescent patient samples, mixed surgical samples, or oral surgical samples were included.

Twenty-nine studies11,18–45 met the criteria and were included in this literature review (Table 1). These 29 descriptive studies examined a variety of psychosocial influences on surgical recovery, with several studies including multiple psychosocial variables (Table 2). Of the surgical studies, 7 were orthopaedic, 12 cardiac, 4 gynecologic/urologic, 3 gastrointestinal, and 3 transplant (ie, cardiac, bone marrow). Sixteen studies (55%) were relatively small, with sample sizes <100.20,22–24,29,30,32,34,36,37,39–42,44 Several studies examined the influence of more than one psychosocial factor and evaluated factors across multiple surgical outcomes; they are included across all relevant psychosocial categories and all relevant outcomes. (See Appendices A-E for detailed information on sample size, type of surgery, psychosocial factor, outcome type, and measurement type [http://www.jaaos.org/cgi/content/full/14/7/397/DC1]). Orthopaedic studies are noted throughout.

Table 1
Table 1:
Methodologic Characteristics of Reviewed Surgery Studies11,18-45
Table 2
Table 2:
Psychosocial Variables Used to Predict Surgical Outcome

Mood Factors

Mood factors were represented by study variables that reflected and/or emphasized moods, feelings, and emotional responses to situations or events. Numerous measures were used to assess mood factors. Some assessed transient feelings (eg, momentary distress about surgery); others assessed chronic moods lasting weeks or months (eg, chronic stress, depression). In addition, although some measures assessed the presence of a specific feeling (eg, hostility, worry), others assessed general emotional distress (ie, simultaneously assessing several negative feelings) or the presence of a mood syndrome that included mood states, physical symptoms, and/or behavioral manifestations of a mood disturbance (eg, depression scale). Finally, some measures assessed the presence of specific types of emotional difficulties (eg, history of anxiety or depression).

Twenty studies11,18–30,32,39,40,42,44,45 investigated the predictive ability of the following mood variables: anxiety, stress, distress, worry, anger, hostility, depressed mood, general emotional state, and presence of emotional difficulties. (See Appendices A-E for a review of study results by psychosocial factor [http://www.jaaos.org/cgi/content/full/14/7/397/DC1]). Nineteen of 47 surgical outcomes were predicted by a mood factor (40%), which indicates that mood factors can play a substantial role in recovery across diverse patient populations and surgical procedures.

Anxiety

Preoperatively assessed anxiety was predictive of 5 of 13 surgical outcomes (38%) across diverse studies. Preoperative anxiety successfully predicted either clinical or selfreport ratings of outcome in three studies, including two orthopaedic (ie, lumbar spine) surgical studies18,19 and one cardiac surgery.11 Outcome assessments ranged from 3 days to 1 year postoperatively. Trait anxiety was predictive of the need for anesthesia in gynecologic patients20 and length of hospital stay in cholecystectomy patients.21

Stress

Preoperative somatic stress (ie, the number of reported physical symptoms of stress) was predictive of 1-year postoperative clinical ratings of recovery in one lumbar surgical study.19 Furthermore, preoperative distress was significantly associated with mortality in a study following cardiac transplant patients up to 56 months postoperatively.22 In two other stress studies, however, stress was not found to be predictive of surgical outcome.11,23

Worry

Although the influence of worry on surgical outcome was investigated in only one study of gynecologic surgery, it was predictive of three short-term surgical outcomes. Abbott and Abbott23 reported that gynecologic patients who worried more about postoperative effects had an increased need for anesthesia, higher pain 4 hours postoperatively, and higher incidence of postoperative vomiting.

Anger and Hostility

Similarly, preoperative anger, assessed in only one study, significantly predicted outcome. In their study of cardiac patients, Stengrevics et al24 reported that higher preoperative anger was predictive of length of hospital stay. It was not predictive of clinical recovery ratings completed at discharge, however. Two studies10,11 examined the influence of hostility on three surgical outcomes; results revealed that hostility was not predictive of any outcome.

Depression

The influence of depression on surgical outcome was investigated in nine studies, predicting 8 of 14 surgical outcomes (57%). Depression was significantly associated with pain25 and return to work26 in two orthopaedic studies. In addition, depression was predictive of mortality after bone marrow transplantation27 as well as length of hospital stay,28 indices of functional recovery,29 and self-report of medical symptoms.30 The relationship between clinical depression and pain has been well-documented,46,47 supporting the idea that depressed mood is useful as a predictor of surgical outcome when assessing continued pain, long-term disability, and functional recovery.

General Emotional State

Several studies32,39,45 using general emotional measures (eg, degree of emotional reaction, mood disturbance, global mood dimensions) found no significant relationship with surgical outcomes. This strongly indicates that global measures of emotional functioning or general emotional state lack the necessary specificity to be predictors of surgical outcomes.

Mood Factors Summary

At least one mood variable predicted each category of surgical outcome included in this review, which indicates that negative mood states hinder different aspects of the recovery process across time. Although no clear and consistent relationship between specific moods and outcomes emerged, results indicate that (1) specific preoperative worries may be the best predictors of short-term surgical outcomes, (2) preoperative anxiety may best predict patient ratings of recovery, and (3) depression is most likely to predict long-term pain and functional disability. After accounting for clinical factors, however, general measures of mood disturbance lack predictive power.

Attitudinal Factors

Attitudinal factors were represented by measures that assessed beliefs, perceptions, attitudes, and expectancies. The variables included in the studies were the following: positive expectations about surgery and the recovery process, the belief in one's ability to successfully perform a specific behavior that promotes a positive health outcome (ie, selfefficacy), a sense of control over one's health and medical choices (ie, perceived control, internal locus of control), optimistic expectations about the future, and desire for active involvement in the recovery process.

Ten studies23,25,28,31–37 investigated the influence of attitudinal factors on 25 surgical outcomes, reporting 16 significant effects (64%). Attitudinal factors were strong predictors of outcome after accounting for patient and clinical factors and were associated with diverse aspects of surgical recovery, including perception of postoperative pain, need for analgesics, postoperative nausea and vomiting, need for anesthesia, length of hospital stay, functional recovery, and clinical and self-report ratings of recovery.

Positive Expectations

Four studies investigating the role of positive expectations reported an influence on surgical outcomes. In an orthopaedic study, Iversen et al25 found an unexpected association between high expectations of pain relief before lumbar surgery and increased pain 6 months postoperatively. The authors suggested that high expectations of pain relief may be unrealistic with this type of surgery and that patients should be better informed about pain preoperatively. Additionally, Iversen et al25 reported that positive expectations significantly predicted both functional recovery (ie, activities of daily living) and self-report ratings of improved function at 6 months postoperatively.

In contrast, Mahomed et al31 found that patient expectation of pain relief after total joint arthroplasty was associated with actual improvement in pain level and physical functioning. This suggests that positive (but not unrealistically high) expectations are associated with quicker recovery in orthopaedic patients. Finally, in a cardiac transplant study,32 positive patient expectations were associated with nurses' ratings of physical health 6 months postoperatively; in a urologic surgical study,33 patient expectations were associated with selfreports of improved well-being 3 months postoperatively.

Self-Efficacy

The ability of self-efficacy to predict surgical outcome was supported by two studies. Bastone and Kerns34 found that high self-efficacy regarding ability to cope with pain was related to decreased use of analgesics after cardiac surgery; it was not associated with ambulation, however. In another cardiac study, self-efficacy predicted both activities of daily living and return to social functioning at 6 months postoperatively.35

Patient-Perceived Control

Perceived control over one's health was associated with three of seven surgical outcomes. Surprisingly, in their study of gynecology patients, Abbott and Abbott23 reported that internal locus of control was a significant predictor of higher anesthesia use. They hypothesized that the patient with a higher internal locus of control (ie, the belief that one's behavior determines the rewards obtained in life) may have difficulty with general anesthesia, a procedure in which the patient lacks control. In turn, the patient may respond by requiring more anesthetic. In addition, the authors reported that a healthy locus of control was associated with vomiting 4 hours postoperatively. Patients with a higher internal locus of control had greater preoperative cardiovascular activity, and the authors suggested that the combination of cardiovascular activity and high internal locus of control in patients who have little control over immediate surgical procedures may contribute to the likelihood of postoperative vomiting.

In a cardiac surgical study, perceived control over recovery was associated with shorter lengths of hospital stay.36 Together, these two studies suggest that perceived control may be less helpful in situations in which patients lack control, but it may facilitate recovery when patients do have some control over their recovery process (eg, adherence to a rehabilitation program).

Optimistic Outlook and Involvement in Recovery

The influence of an optimistic outlook on life was supported by one cardiac study investigating recovery status several months postoperatively.37 In another study of cardiac patients, desire for involvement (ie, the attitude or desire to be an active participant in one's health care) was associated with two of three surgical outcomes: greater ambulation and shorter length of hospital stay.36

The ability of attitudinal factors to predict surgical outcome was clearly demonstrated in the studies investigating their potential influence. Positive attitudinal factors successfully predicted improved surgical outcomes even after accounting for clinical factors. Positive expectations and self-efficacy demonstrated the strongest relationship with various surgical outcomes. Positive expectations were significantly related to diverse surgical outcomes. Similarly, self-efficacy influenced surgical outcome in three of four outcomes investigated. The utility of these variables was demonstrated across different surgical samples and areas of surgical outcome. In addition, both optimism and desire for involvement were predictors of improved surgical outcomes.

Attitudinal Factors Summary

Attitudinal factors were associated with at least one outcome across all outcome categories, indicating the general usefulness of attitudinal factors as predictors of recovery. However, they demonstrated the strongest association with multiple areas of functional recovery, indicating that attitudinal measures are particularly effective in predicting faster return to performing activities of daily living.

Social Support

Social support is the availability of people who are able to provide assistance or help in the patient's social environment, reflecting both the quality and quantity of social relationships. Diverse aspects of this general concept were assessed, including perceived emotional and practical support, social isolation, extent of social network, and frequency of social contact.

Eleven studies11,22,26,28,30,34,38–41,45 investigated the predictive ability of social support and activity (or social isolation) on 16 diverse surgical outcomes. Social support was predictive of four outcomes (25%). Of the studies reporting these outcomes, two assessed patient self-reports of outcome several months postoperatively,11,38 and two determined follow-up mortality rates.22,39

Three orthopaedic studies examined the influence of social support on functional recovery, but notably, none demonstrated a significant relationship.26,40,41 In a study of ACL reconstruction patients, Brewer et al40 at 6 months postoperatively could not demonstrate a relationship between a social support scale, which assessed satisfaction with support and help received from others, and the ability to perform a oneleg hop. Sharma et al41 developed a social support item determining the number of people available postoperatively for support (ie, spouse, relatives, friends); this measure of social support was not associated with an increased ability to perform daily activities 3 months postoperatively in a sample of patients undergoing knee replacement surgery. In a study of lumbar surgery patients,26 a measure of work-related social support was not associated with the ability to return to work or to perform activities of daily living 2 years postoperatively.

Social support seems to be most related to long-term physical outcome and/or survival. All significant effects were reported in cardiac patients. In cardiac studies, social isolation or lack of social support has been linked to the development and progression of coronary heart disease,48,49 indicating that positive support may have a long-term general health benefit. Social support is less influential on short-term surgical outcomes and for patients who are undergoing less invasive procedures.

Coping Factors

Coping factors include measures that assess patient strategies for managing the demands of injury or disease, surgery, and recovery. Among these factors are coping styles, such as active, passive, avoidant, and problem-solving. Five studies18–20,22,42 investigated the influence of coping on four surgical outcomes, with two studies22,42 reporting a significant effect.

In a study of patients undergoing coronary artery bypass grafting surgery, Agren et al42 examined the influence of two coping styles on functional recovery: minimizing versus accepting. After controlling for age and clinical severity, patients who minimized symptoms were more likely to be working full time 1 year after surgery compared with patients who accepted their symptoms. Chacko et al22 determined that ratings of pretransplant coping were predictive of survival time. In contrast, two orthopaedic studies of lumbar surgery patients investigating the influence of vigilant and avoidant coping styles18 and active and passive pain coping strategies19 were not associated with self-report or clinical ratings of recovery.

The relationship between coping styles and health has been studied extensively, with most studies investigating the influence of coping on psychological adjustment. Relatively few studies have examined the influence of coping on physical health,50 and fewer still have examined its influence on surgical outcomes. A recent review on coping and health outcomes indicates that coping strategies are differentially associated across health outcomes.51 However, coping appeared to be related more to psychological health than to physical health outcomes. Although the results of this literature review indicate that coping may be associated with positive surgical outcomes, more research is needed on the relationship between coping and physical health.

Personality Factors

Five studies, including one orthopaedic study, examined the influence of six personality variables on surgical outcome: neuroticism, extroversion, self-esteem, motivation, ego strength, and inadequacy. Only one personality variable was associated with surgical outcome. In a study investigating the role of personality variables in predicting outcome for women undergoing urologic surgery, a relationship between neuroticism and patient self-report of unsuccessful surgical outcomes for urinary incontinence30 was found 1 year postoperatively. The results of these studies indicate that global personality measures are not strong predictors of physical recovery after taking into account clinical factors. Although specific personality traits may have an impact on certain indices of health, their ability to predict surgical outcomes is limited. Other psychosocial factors appear to play a more important role in the variability of patient recovery.

Orthopaedic Studies

Seven orthopaedic studies were included in this literature review.18,19,25,26,40,41,52 The results of these studies were consistent with the results of the total sample of studies. Specifically, five studies18,19,25,26,40 investigated the influence of mood factors on 10 surgical outcomes. Four of the orthopaedic outcomes were predicted by three negative moods: stress, anxiety, and depression.18,19,25,26 Although only one orthopaedic study investigated attitudinal factors, positive expectations were associated with all three outcomes: pain, functional recovery, and self-report ratings of recovery.25 These studies support the influence of mood and attitudinal factors on recovery after orthopaedic surgery.

In contrast, three orthopaedic studies26,40,41 investigated the ability of social support to predict recovery outcomes based on five functional recovery and self-report ratings. Social support was not associated with any of these outcomes. However, a recent study of patients undergoing hip replacement52 indicates that negative support may be more strongly related to recovery than positive support. Specifically, the absence of negative support (eg, adverse pressure or criticism from significant others) was more strongly related to improvement in both self-reported and clinically rated knee pain than was the presence of positive support. Thus, although positive support may not facilitate recovery after orthopaedic surgery, negative support hinders it.

Negative results were reported in two orthopaedic studies investigating the influence of coping strategies18,19 and in one study investigating a personality variable,41 suggesting that mood and attitudinal factors are the most important psychosocial factors for orthopaedic surgeons to consider.

For the orthopaedic surgeon, patient and clinical factors, such as age and extent of injury, will form the basis of predicting the length of time until full recovery. However, psychosocial factors also have a role in promoting physical recovery after surgery. The literature indicates that psychosocial factors are important preoperative considerations. Key questions for the surgeon to consider are summarized in Table 3.

Table 3
Table 3:
Questions to Consider During Presurgical Assessment of Psychosocial Factors

Mood factors may play an important role: patients who are worried, anxious, or depressed preoperatively are likely to report slower recovery postoperatively. Therefore, it may be helpful to assess patient moods associated with (1) the injury or illness leading to surgery, (2) planned surgical procedures, and (3) the anticipation of the recovery process.

Attitudinal factors also are important to assess. Although the patient with positive expectations may have a smoother recovery, unrealistically high expectations may be detrimental. Several factors are important in estimating recovery time: preoperative discussion regarding patient expectations of postoperative pain and discomfort and the perceived threshold for managing such pain and discomfort, level of patient desire to fully and actively participate in the rehabilitation process, and patient confidence in his or her own ability to do what is necessary to promote rapid recovery.

Negative social support and coping strategies also are likely to influence surgical outcomes but may be less clinically important for the time-pressed surgeon to assess preoperatively. Consideration of these factors may become more important postoperatively, especially for the patient undergoing major orthopaedic surgery that requires longer recovery times.

Summary

To improve patient care, it is critical to determine the factors that promote faster and more complete physical recovery from surgery. Patient demographic and clinical factors are primary influences on surgical outcome and are clinically important to consider when estimating recovery time. But even when these factors are taken into consideration, there remains a substantial variability in recovery time across patients for most surgeries. Physicians should be aware of the additional factors that influence recovery and the circumstances in which those factors may become important predictors of outcome.

Based on a systematic review of 29 studies investigating psychosocial influences on surgical outcomes, psychosocial factors are predictive of surgical outcome after controlling for clinical factors (eg, age, sex, comorbidity). In particular, mood and attitudinal factors are associated with diverse surgical outcomes, including need for anesthesia, length of hospital stay, functional recovery, and patient selfreport ratings of recovery. In addition, mood and attitudinal factors have a wide-ranging effect on outcome, predicting a variety of both positive and negative surgical outcomes across a wide range of surgical procedures. Although fewer studies investigated their influence, coping factors also show promise as a predictor of clinical outcome. Social support was somewhat predictive of outcome, whereas personality factors were least predictive. The orthopaedic surgeon may want the patient to go through appropriate screening (eg, Minnesota Multiphasic Personality Inventory, psychiatric evaluation) as part of the preoperative planning.

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Citation numbers printed in bold type indicate references published within the past 5 years.

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