Elisabetta Patron

Association between depression and heart rate variability in patients after cardiac surgery: A pilot study☆

OBJECTIVE Depression is a risk factor for cardiovascular diseases. Reduced heart rate variability (HRV), which reflects altered autonomic nervous system activity, has been suggested as one of the mechanisms linking depression to cardiovascular diseases. However, the relationship between depression and HRV has not yet been investigated in patients undergone cardiac surgery. Therefore, the main aim of this study was to examine whether postoperative depression could be related to reduced HRV. METHODS Eleven patients with depression and 22 patients without depression, who had undergone cardiac surgery, were enrolled postoperatively. In all patients, HRV was derived from a four-minute blood volume pulse recording at rest. Analyses of covariance and partial correlations, while controlling for anxiety, were used to examine the associations between postoperative depression and each HRV parameter. RESULTS Compared to non-depressed patients, patients with depression showed significantly lower standard deviation of N-to-N intervals (SDNN) (p=.02), root mean square successive difference of N-to-N intervals (rMSSD) (p=.001), and high-frequency power (p=.002). Partial correlation analyses showed that depression was inversely related to SDNN (r=-.49, p=.005), rMSSD (r=-.58, p=.001), and high-frequency power (r=-.41, p=.02), whereas it was unrelated to other HRV parameters (ps>.09). CONCLUSIONS The current findings extend the depression-reduced HRV relationship to the patients after cardiac surgery. Also, our study suggests that postoperative depression is more likely to be associated with reduced vagal modulation on the heart than with excessive sympathetic activity.

Preexisting depressive symptoms are associated with long-term cognitive decline in patients after cardiac surgery.

OBJECTIVE To examine whether preoperative psychological dysfunctions rather than intraoperative factors may differentially predict short- and long-term postoperative cognitive decline (POCD) in patients after cardiac surgery. METHOD Forty-two patients completed a psychological evaluation, including the Trail Making Test Part A and B (TMT-A/B), the memory with 10/30-s interference, the phonemic verbal fluency and the Center for Epidemiological Studies of Depression (CES-D) scale for cognitive functions and depressive symptoms, respectively, before surgery, at discharge and at 18-month follow-up. RESULTS Ten (24%) and 11 (26%) patients showed POCD at discharge and at 18-month follow-up, respectively. The duration of cardiopulmonary bypass significantly predicted short-term POCD [odds ratio (OR)=1.04, P<.05], whereas preoperative psychological factors were unrelated to cognitive decline at discharge. Conversely, long-term cognitive decline after cardiac surgery was significantly predicted by preoperative scores in the CES-D (OR=1.26, P<.03) but not by intraoperative variables (all Ps >.23). CONCLUSIONS Our findings showed that preexisting depressive symptoms rather than perioperative risk factors are associated with cognitive decline 18 months after cardiac surgery. This study suggests that a preoperative psychological evaluation of depressive symptoms is essential to anticipate which patients are likely to show long-term cognitive decline after cardiac surgery.

Depression and reduced heart rate variability after cardiac surgery: The mediating role of emotion regulation

BACKGROUND Heart rate variability (HRV), as an index of autonomic nervous system (ANS) functioning, is reduced by depression after cardiac surgery, but the underlying mechanisms of this relationship are poorly understood. Poor emotion regulation as a core symptom of depression has also been associated with altered ANS functioning. The present study aimed to examine whether emotion dysregulation could be a mediator of the depression-reduced HRV relationship observed after cardiac surgery. METHODS Self-reported emotion regulation and four-minute HRV were measured in 25 depressed and 43 nondepressed patients after cardiac surgery. Mediation analysis was conducted to evaluate emotion regulation as a mediator of the depression-reduced HRV relationship. RESULTS Compared to nondepressed patients, those with depression showed lower standard deviation of normal-to-normal (NN) intervals (p<.05), root mean square successive difference of NN intervals (p<.004), and number of interval differences of successive NN intervals greater than 50ms (NN50) (p<.05). Increased low frequency (LF) in normalized units (n.u.) and reduced high frequency (HF) n.u. were also found in depressed compared to nondepressed patients (ps<.01). Mediation analysis revealed that suppression of emotion-expressive behavior partially mediated the effect of depression on LF n.u. and HF n.u. CONCLUSIONS Results confirmed previous findings showing that depression is associated with reduced HRV, especially a reduced vagal tone and a sympathovagal imbalance, after cardiac surgery. This study also provides preliminary evidence that increased trait levels of suppression of emotion-expressive behavior may mediate the depression-related sympathovagal imbalance after cardiac surgery.

Change in behavioral functional capacity is associated with preexisting cognitive function rather than with cognitive decline in patients 1 year after cardiac surgery

OBJECTIVE The objective was to examine whether preexisting cognitive function rather than cognitive decline associated with intraoperative procedures may predict change in behavioral functional capacity in patients 1 year after cardiac surgery. METHOD Forty-five patients completed a cognitive evaluation, including the Trail Making Test part B (TMT-B) for attention and psychomotor speed, the Memory with 10-s interference for working memory, the Digit Span test for short-term memory and the Instrumental Activities of Daily Living (IADLs) questionnaire for behavioral functional capacity, before surgery and 1 year after cardiac surgery. RESULTS Sixteen patients (36%) exhibited cognitive decline after cardiac surgery. Preoperative scores on TMT-B significantly predicted change in behavioral functional capacity as measured by IADLs (beta = 0.371, P < .05), whereas the postoperative cognitive decline and intraoperative variables were unrelated to residualized change scores in IADLs (all Ps > .08). CONCLUSIONS Preexisting cognitive dysfunctions as assessed by TMT-B can be a marker of preoperative brain dysfunction, which, in turn, in addition to brain damage caused by cardiac surgery procedures, may further predispose patients to poor behavioral functional capacity and outcome 1 year after surgery. Impaired cognitive functions before surgery should be considered when evaluating the effects of cardiac surgery procedures on long-term behavioral functional status of patients.

Preoperative and Perioperative Predictors of Reactive and Persistent Depression After Cardiac Surgery: A Three-Month Follow-up Study

BACKGROUND Depression is commonly reported in patients after cardiac surgery and increases the risk of postoperative cardiac morbidity or mortality or both. Although preoperative depression has been implicated as the strongest predictor of depression after surgery, the characteristics thought to influence reactive or persistent depression have been poorly investigated in cardiac surgery patients. OBJECTIVE Therefore, the main aim of this study was to examine whether pre-existing depression rather than perioperative variables may predict postoperative reactive or persistent depression. METHODS Overall, 96 patients completed a psychologic evaluation, including the Center for Epidemiologic Studies of Depression scale and the State and Trait Anxiety Inventory for depression and anxiety, respectively, before surgery and at 3-month follow-up. RESULTS A total of 27 (28%) and 24 (25%) patients had depression preoperatively and at 3-month follow-up, respectively. Postoperative depression was predicted by preoperative scores in Center for Epidemiologic Studies of Depression scale (β = 0.29, p < 0.05) and European System for Cardiac Operative Risk Evaluation (β = 0.22, p < 0.04), but not by procedure-related variables (p > 0.75). Specifically, patients with reactive depression showed greater European System for Cardiac Operative Risk Evaluation than those without depression (p < 0.05), whereas patients with persistent depression had greater preoperative Center for Epidemiologic Studies of Depression scores than those whose depression improved after surgery (p < 0.01). CONCLUSIONS The severity of pre-existing depression and biomedical risk factors can be markers of depression-related risk 3 months after cardiac surgery in patients with persistent and reactive depression, respectively. An integrated psychologic and biomedical evaluation is essential to anticipate which patients are likely to show depression after cardiac surgery.

Preexisting cognitive status is associated with reduced behavioral functional capacity in patients 3 months after cardiac surgery: an extension study☆ , ☆☆

OBJECTIVE To examine whether preexisting cognitive status rather than short- and middle-term postoperative cognitive decline (POCD) may differentially account for behavioral functional capacity 3 months after cardiac surgery. METHOD Seventy-nine patients completed a psychological evaluation, including the Trail Making Test Part B, the memory with 10-s interference, the phonemic fluency and the Instrumental Activities of Daily Living (IADLs) questionnaire for cognitive functions and behavioral functional capacity, respectively, before surgery, at discharge and at 3-month follow-up. RESULTS Thirty-one (39%) and 22 (28%) patients showed POCD at discharge and at 3-month follow-up, respectively. Preoperative cognitive status was significantly associated with change in behavioral functional capacity 3 months after surgery (Ps<.003), whereas short- and middle-term POCD and intraoperative risk factors were unrelated to residualized change in IADLs scores (all Ps>.095). CONCLUSIONS Preexisting cognitive deficit, especially working memory deficit, rather than short- and middle-term POCD related to intraoperative risk factors is associated with poor behavioral functional capacity 3 months after cardiac surgery. The present study therefore suggests that a preoperative cognitive evaluation is essential to anticipate which patients are likely to show a decline in behavioral functional capacity after cardiac surgery.

Preoperative biomedical risk and depressive symptoms are differently associated with reduced health-related quality of life in patients 1year after cardiac surgery

OBJECTIVE To examine whether preoperative biomedical risk and depressive symptoms were associated with physical and mental components of health-related quality of life (HRQoL) in patients 1year after cardiac surgery. METHOD Seventy-five patients completed a psychological evaluation, including the Center for Epidemiological Study of Depression scale, the 12-item Short-Form Physical Component Scale (SF-12-PCS) and Mental Component Scale (SF-12-MCS), the Instrumental Activities of Daily Living questionnaire for depressive symptoms and HRQoL, respectively, before surgery and at 1-year follow-up. RESULTS Preoperative depressive symptoms predicted the SF-12-PCS (beta=-.22, P<.05) and SF-12-MCS (beta=-.30, P<.04) scores in patients 1year after cardiac surgery, whereas the European System for Cardiac Operative Risk Evaluation was associated with SF-12-PCS (beta=-.28, P<.02), but not SF-12-MCS (beta=.01, P=.97) scores postoperatively. CONCLUSIONS The current findings showed that preoperative depressive symptoms are associated with poor physical and mental components of HRQoL, whereas high biomedical risk predicts reduced physical, but not mental, functioning in patients postoperatively. This study suggests that a preoperative assessment of depressive symptoms in addition to the evaluation of common biomedical risk factors is essential to anticipate which patients are likely to show poor HRQoL after cardiac surgery.

Depression is associated with increased vagal withdrawal during unpleasant emotional imagery after cardiac surgery

BACKGROUND The aim of this study was to examine the influence of depression on heart rate and heart rate variability (HRV) during emotional imagery in patients after cardiac surgery. METHODS Based on the scores of the Center for Epidemiological Studies of Depression (CES-D) scale, 28 patients after cardiac surgery were assigned either to the group with depression (CES-D scores ≥ 16; N = 14) or the one without depression (CES-D scores<16; N = 14). Each patient completed a rest period and an emotional imagery including pleasant, neutral and unpleasant scripts. Inter-beat intervals (IBIs) and HRV were measured during the entire protocol. RESULTS Compared to nondepressed patients, those with depression had greater reductions in high frequency expressed in normalized units (HF n.u.) during the imaging of the unpleasant script (p = .003, Cohens d = 1.34). Moreover, HF n.u. were lower during the imaging of the unpleasant script than the pleasant one in depressed patients only (p = .020, Cohens d = 0.55). CES-D scores were also inversely correlated with residualized changes in IBIs (r = -.38, p = .045) and HF n.u. (r = -.49, p = .008) from rest to the imaging of the unpleasant script. CONCLUSIONS The relationship between depression and increased vagal withdrawal during unpleasant emotional imagery extends to patients after cardiac surgery. The present study suggests that increased vagal withdrawal to negative emotions in patients after cardiac surgery may mediate the conferral of cardiac risk by depression.

Somatic-Affective, But Not Cognitive-Depressive Symptoms are Associated With Reduced Health–Related Quality of Life in Patients With Congestive Heart Failure

BACKGROUND Depression has been associated with poor health-related quality of life (HRQoL) in patients with congestive heart failure (CHF). However, to date, whether somatic-affective and cognitive-depressive symptoms differently contribute to poor HRQoL and behavioral functional capacity in patients with CHF has yet to be investigated. OBJECTIVE To examine the differential influence of somatic-affective vs cognitive-depressive symptoms on HRQoL and behavioral functional capacity in CHF patients. METHOD Overall, 55 patients with CHF completed a psychologic evaluation, including the Minnesota Living with Heart Failure Questionnaire, the Beck Depression Inventory-II, and the Beck Anxiety Inventory for HRQoL, depressive, and anxiety symptoms, respectively. The patients completed the Instrumental Activities of Daily Living Questionnaire and the 6-minute walk test for behavioral functional capacity. Hierarchical regression analyses were used to predict HRQoL and behavioral functional capacity from Beck Depression Inventory-II and Beck Anxiety Inventory scores. RESULTS Somatic-affective depressive symptoms were associated with physical (β = 0.37, p = 0.005) and emotional (β = 0.39, p = 0.008) Minnesota Living with Heart Failure Questionnaire subscale scores. Likewise, somatic-affective depressive symptoms predicted Instrumental Activities of Daily Livings Scores (β = 0.43, p = 0.004) and distance ambulated during the 6-minute walk test (β = -0.36, p = 0.029). By contrast, cognitive-depressive symptoms and anxiety were unrelated to HRQoL and behavioral functional capacity (all p > 0.05). CONCLUSIONS These findings showed that somatic-affective depressive symptoms, but not cognitive-depressive symptoms and anxiety, are associated with poor HRQoL and behavioral functional capacity independent of age, clinical functional status, and medical comorbidities. This study suggests that patients with CHF with somatic-affective rather than cognitive-depressive symptoms or anxiety may be at greater risk of poor HRQoL and behavioral functional capacity.

Are patient- or procedure-related factors relevant to middle-term cognitive decline after cardiac surgery? This is the question.

Postoperative cognitive decline (POCD) is a frequent complication after cardiac surgery.1 Cognitive decline at discharge from the hospital, namely, short-term POCD, is mainly due to procedure-related factors, such as cerebral hypoperfusion and microembolization associated with the duration of cardiopulmonary bypass (CPB).2 Conversely, long-term (≥1 year) POCD is more likely to be ascribed to patientrather than procedurerelated factors, such as low educational level, pre-existing cerebrovascular disease, cognitive impairment or depression.1,3 Among these factors, it has been shown that pre-existing cognitive impairment plays a key role in long-term cognitive decline after surgery. Indeed, 20 to 46% of patients awaiting cardiac surgery have preoperative cognitive deficits,4 which may account for the high incidence of POCD. Despite the importance of procedureand patientrelated factors for shortand long-term POCD, respectively, the influence of such factors on cognitive decline at middle-term follow-up (i.e., three months after cardiac surgery) has been poorly investigated. The latter period of time is particularly interesting given that there is evidence that it is influenced by both patientand procedure-related factors.2,5 Importantly, the three-month follow-up is also critical for postsurgical recovery given that it has been indicated as the first time interval for post-convalescent assessment relevant to postoperative cognitive outcome.6 Therefore, after local ethics committee approval, we examined the influence of such factors on cognitive decline at middle-term follow-up in 79 patients who were admitted for firsttime elective cardiac surgery with CPB and gave their informed written consent (for the characteristics of the sample, see Ref. 7). Differently from our previous study focusing on decline in behavioral functional capacity,7 the present study aimed to examine whether preexisting cognitive status and the duration of CPB would be differentially associated with middle-term POCD. Using the 1-SD criterion, we found that 22 (28%) patients showed cognitive decline at three-month follow-up (for the descriptive statistics of each cognitive performance, see Ref. 7). Hierarchical logistic regression revealed that pre-existing cognitive status, as evaluated by a composite cognitive index (CI; the greater the CI, the better the cognitive performance),7 but not the duration of CPB, was associated with POCD three months after cardiac surgery. Specifically, for a one-unit decrease in CI, the odds of exhibiting middleterm POCD increased by 88% (Table 1). As the second step, a multivariate analysis of variance yielded an overall difference between the groups (with POCD, without POCD) in preoperative cognitive scores, Wilks λ = 0.70, F(3, 75) = 10.95, p<0.001, ηp = .31: patients with POCD had a worse performance in each cognitive test than those without POCD. Among the cognitive domains assessed, the greatest difference between the groups was observed for preoperative phonemic fluency (p<0.001, ηp = .25). Overall, these novel findings add to our previous study reporting the association between pre-existing cognitive deficit and poor behavioral functional capacity Are patientor procedure-related factors relevant to middle-term cognitive decline after cardiac surgery? This is the question