Factors influencing the outcomes of patients with both coronary artery disease and diabetes enrolled in standard cardiac rehabilitation programs: a literature review

Benefits of cardiac rehabilitation following acute coronary syndrome for patients with and without diabetes: a systematic review and meta-analysis

Aim

The benefits of cardiac rehabilitation (CR) after acute coronary syndrome (ACS) are well established. However, the relative benefit of CR in those with comorbidities, including diabetes, is not well understood. This systematic review and meta-analysis examined the benefit of CR on exercise capacity and secondary outcomes in ACS patients with a co-diagnosis of diabetes compared to those without.

Methods

Five databases were searched in May 2021 for randomised controlled trials (RCTs) and observational studies reporting CR outcomes in ACS patients with and without diabetes. The primary outcome of this study was exercise capacity expressed as metabolic equivalents (METs) at the end of CR and ≥ 12-month follow-up. Secondary outcomes included health-related quality of life, cardiovascular- and diabetes-related outcomes, lifestyle-related outcomes, psychological wellbeing, and return to work. If relevant/possible, studies were pooled using random-effects meta-analysis.

Results

A total of 28 studies were included, of which 20 reported exercise capacity and 18 reported secondary outcomes. Overall, the studies were judged to have a high risk of bias. Meta-analysis of exercise capacity was undertaken based on 18 studies (no RCTs) including 15,288 patients, of whom 3369 had diabetes. This analysis showed a statistically significant smaller difference in the change in METs in ACS patients with diabetes (standardised mean difference (SMD) from baseline to end of CR: − 0.15 (95% CI: − 0.24 to − 0.06); SMD at the ≥ 12-month follow-up: − 0.16 (95% CI: − 0.23 to − 0.10, four studies)).

Conclusion

The benefit of CR on exercise capacity in ACS patients was lower in those with diabetes than in those without diabetes. Given the small magnitude of this difference and the substantial heterogeneity in the results of the study caused by diverse study designs and methodologies, further research is needed to confirm our findings. Future work should seek to eliminate bias in observational studies and evaluate CR based on comprehensive outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-022-02723-5.

What follow-up care and self-management support do patients with type 2 diabetes want after their first acute coronary event? A qualitative study

AIMS

Despite diabetes patients' efforts to control their disease, many of them are confronted with an acute coronary event. This may evoke depressive feelings and self-management may be complicated. According to the American Diabetes Association, the transition from hospital to home after an acute coronary event (ACE) is a high-risk time for diabetes patients; it should be improved. Before developing an intervention for diabetes patients with an ACE in the period after discharge from hospital, we want to gain a detailed understanding of patients' views, perceptions and feelings in this respect.

METHODS

Qualitative design. Two semi-structured focus groups were conducted with 14 T2DM patients (71% male, aged 61-77 years) with a recent ACE. One focus group with partners (67% male, aged 64-75 years) was held. All interviews were transcribed verbatim and analyzed by two independent researchers.

RESULTS

Patients believed that coping with an ACE differs between patients with and without T2DM. They had problems with physical exercise, sexuality and pharmacotherapy. Patients and partners were neither satisfied with the amount of information, especially on the combination of T2DM and ACE, nor with the support offered by healthcare professionals after discharge. Participants would appreciate tailored self-management support after discharge from hospital.

CONCLUSIONS

Patients with T2DM and their partners lack tailored support after a first ACE. Our findings underpin the ADA recommendations to improve the transition from hospital to home. The results of our study will help to determine the exact content of a self-management support program delivered at home to help this specific group of patients to cope with both conditions.

Tailored support for type 2 diabetes patients with an acute coronary event after discharge from hospital - design and development of a randomised controlled trial

BACKGROUND

Type 2 diabetes mellitus patients with an acute coronary event (ACE) experience decreased quality of life and increased distress. According to the American Diabetes Association, discharge from the hospital is a time of increased distress for all patients. Tailored support specific to diabetes is scarce in that period. We developed an intervention based on Bandura's Social Cognitive Theory, Leventhal's Common Sense Model, and results of focus groups. The aim of this study is to evaluate the effectiveness of the intervention to reduce distress in type 2 diabetes patients who experienced a first ACE.

METHODS

Randomised controlled trial. Two hundred patients are recruited in thirteen hospitals. A diabetes nurse visits the patients in the intervention group (n = 100) at home within three weeks after discharge from hospital, and again after two weeks and two months. The control group (n = 100) receives a consultation by telephone. The primary outcome is diabetes-related distress, measured with the Problem Areas in Diabetes (PAID) questionnaire. Secondary outcomes are well-being, health status, anxiety, depression, HbA1c, blood pressure and lipids. Mediating variables are self-management, self-efficacy and illness representations. Outcomes are measured with questionnaires directly after discharge from hospital and five months later. Biomedical variables are obtained from the records from the primary care physician and the hospital. Differences between groups in change over time are analysed according to the intention-to-treat principle. The Holm-Bonferroni correction is used to adjust for multiplicity.

DISCUSSION

Type 2 diabetes patients who experience a first ACE need tailored support after discharge from the hospital. This trial will provide evidence on the effectiveness of a supportive intervention in reducing distress in these patients.

TRIAL REGISTRATION

NCT01801631.

Oxidative stress and myocardial injury in the diabetic heart

Reactive oxygen or nitrogen species play an integral role in both myocardial injury and repair. This dichotomy is differentiated at the level of species type, amount and duration of free radical generated. Homeostatic mechanisms designed to prevent free radical generation in the first instance, scavenge, or enzymatically convert them to less toxic forms and water, playing crucial roles in the maintenance of cellular structure and function. The outcome between functional recovery and dysfunction is dependent upon the inherent ability of these homeostatic antioxidant defences to withstand acute free radical generation, in the order of seconds to minutes. Alternatively, pre-existent antioxidant capacity (from intracellular and extracellular sources) may regulate the degree of free radical generation. This converts reactive oxygen and nitrogen species to the role of second messenger involved in cell signalling. The adaptive capacity of the cell is altered by the balance between death or survival signal converging at the level of the mitochondria, with distinct pathophysiological consequences that extends the period of injury from hours to days and weeks. Hyperglycaemia, hyperlipidaemia and insulin resistance enhance oxidative stress in the diabetic myocardium that cannot adapt to ischaemia-reperfusion. Altered glucose flux, mitochondrial derangements and nitric oxide synthase uncoupling in the presence of decreased antioxidant defence and impaired prosurvival cell signalling may render the diabetic myocardium more vulnerable to injury, remodelling and heart failure.