Higher Burnout Is Associated With Poorer Physical Recovery,Worse Quality Of Life And Lower HRV After ACS

[Objective]Coronary heart disease has become one of the most main causes to death and disability in the global world. Lots of studies and epidemiological surveys showed that the chronic stress play an important role in the occurrence, progress and prognosis of coronary heart disease. Anxiety and depression, two common negative affective responses, have been proved to be the risk factors that predict adverse outcomes of coronary heart disease. Burnout is another negative affective response, however, rare studies implied the association between burnout and adverse outcomes of coronary heart disease. The aim of this study is to detect the effect of burnout on the recovery after acute coronary syndrome(ACS), including the recovery of physical capacity, quality of life and heart rate variability (HRV).[Method]1. The participants were patients with their first ACS and admitted to the Cardiology Department of the First Affiliated Hospital of Kunming Medical University during March2012to March2014. All the participants signed the informed consent.2. Participants’basic data, including Demographic characteristics, tobacco and alcohol addiction, past medical history, family history of heart disease, clinical manifestations and disease diagnosis were collected during their admission.3. Burnout was assessed by the general burnout subscale of Copenhagen Burnout Inventory (CBI) during hospitalization. Based on the upper quartile(P75) of general burnout score, all patients were divided into two groups:high burnout group (burnout score≥P75) and low burnout group (burnout score<P75).4. Participants were followed up after one month of their discharge. Burnout level was assessed by the same subscale. Based on the changing of burnout score, the participants were divided into four subgroups:The patients whose burnout scores were still more than or equal to P75were defined as sustained high burnout subgroup. The patients whose burnout scores were still less than P75were defined as sustained low burnout subgroup. Those whose scores rise from<P75to≥P75were defined as burnout raise group. And those whose scores reduce from≥P75to<P75were defined as burnout reduce group.5. At their first follow-up, all participants were asked to do a physical capacity test, whose name is Short Physical Performance Battery(SPPB). Medical Outcome Study Short Form-8(SF-8) and Seattle Angina Questionnaire(SAQ) were used to evaluate the quality of life. The heart rate variability (HRV) was analyzed by24-hour holter monitoring.6, Statistical analyses were performed by SPSS19.0software package. Student’s t-test or one-way ANOVA for continuous variables and the chi-square test for categorical factors were applied to compare difference between the high burnout group and low burnout group, and among above mentioned4subgroups as well. P value of<0.05was considered to be significant. Multiple stepwise linear regression models were developed to determine the association between burnout and SPPB score, quality of life, and HRV parameters respectively, controlling for confounding factors, i.e. age, sex, education, ACS types, smoking, drinking, history of hypertension and diabetes, and family history of coronary disease, etc. Variables with a p value<0.10were included, and p value>0.20were excluded from these models.[Results]1. Nighty-four participants were enrolled in this study, and3subjects quitted. The rest91subjects completed their follow-up eventually. P75of general burnout scores before patients" discharge was58.33. Based on P75, all patients were divided into high burnout group(n=26) and low burnout group(n=65). After one month of discharge,17subjects sustained high burnout, and58kept low burnout. Nine subjects had an increasing burnout score from low to high, and7subjects had a decreasing score from high to low.2. The SPPB score, SF-8score and SAQ score of high burnout group were significantly lower than those of low burnout group (p<0.05), The stepwise multiple linear regression models showed a negative relationship between burnout level and physical capacity and quality of life respectively. The higher of the burnout level, the lower the physical score and quality of life.3. The SDNN, Ln(ULF), Ln(VLF) and Ln(TP) of HRV parameters of high burnout group were significantly lower than those of low burnout group (p<0.05), The stepwise multiple linear regression models showed a negative relationship between burnout level and HRV parameters respectively. The higher of the burnout level, the lower the HRV parameters.4. Comparing with sustained low burnout group, burnout raise group presented lower SPPB scores, lower physical health scores of SF-8, and lower Anginal Stability(AS), Anginal Frequency (AF),Treatment Satisfaction(TS) and Disease Perception(DP) of SAQ. The difference was statistically significant (p<0.05).5.The D-value of burnout score (the score after one month minus the score during hospitalization) was correlated negatively with SPPB scores, SF-8scores, Physical Limitation,(PL),AS,TS and DP of SAQ. The higher the burnout level, the poorer the physical capacity and quality of life.[Conclusion]1. Both subjective and objective assessment showed the ACS patients with high burnout level experience worse physical recovery.2. ACS patients with high burnout level experience worse quality of life, including lower self evaluation of physical recovery, higher frequency and unstable angina, lower treatment satisfaction and disease perception.3. ACS patients with high burnout level have lower HRV, including SDNN, a time domain parameter, and comprehensive frequency domain index.