Effects of tiered cardiac rehabilitation on CRP, TNF-α, and physical endurance in older adults with coronary heart disease

Abstract

Coronary heart disease (CHD) is a highly prevalent disease in the elderly population, with atherosclerosis as its pathology, which can also be viewed as a chronic inflammatory response of the organism. Regular moderate-intensity exercise can direct the immune response toward an anti-inflammatory state, which is beneficial for improving the health and exercise tolerance. In cardiac rehabilitation, attention to the management of inflammatory factors as well as the improvement of exercise endurance is beneficial for the rehabilitation of elderly patients with coronary artery disease. This study investigates the impact of tiered cardiac rehabilitation programs on levels of C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-α), and the capacity for physical exertion in older CHD patients. From March 2020 to April 2022, 94 elderly patients with CHD visiting our institution were recruited and randomly allocated into either a control group or an observation group, each comprising 47 participants. The standard care group participated in traditional rehabilitation exercises, whereas the experimental group received customized, tiered, cardiac rehabilitation interventions. We assessed the variations in CRP and tumor necrosis factor alpha (TNF-α) levels, along with exercise capacity, before and after treatment in both groups. The result shows that significant reductions in CRP and TNF-α levels were seen in the experimental group after 4 and 12 weeks, compared to the standard care group. Analysis showed clear trends in CRP and TNF-α changes over the interventions, with the experimental group showing better results. CRP levels decreased consistently, while TNF-α levels stayed stable. The experimental group also showed improvements in physical endurance measures compared to the control group. Interleukin 6 (IL-6) and fibrinogen (Fib) in the observation group decreased compared with the control group (P < 0.01). After 12 weeks of treatment, CRP and TNF-α showed significant negative correlation with exercise endurance index - 6 min walking test (6 MWT), anaerobic threshold (AT), maximum oxygen consumption (VO_2max), and exercise duration (ED); significant positive correlation between cardiac rehabilitation grade and exercise endurance index (6 MWT, AT, VO_2max and ED); and both groups experienced cardiovascular adverse events and exercise muscle injury. The analysis shows that the graded nursing of cardiac rehabilitation can effectively reduce the levels of CRP, TNF-α, IL-6, and Fib in elderly patients with CHD and significantly improve the exercise endurance of patients with good safety.

Keywords: CRP; coronary heart disease; elderly; exercise tolerance; stratified cardiac rehabilitation.

Graphical abstract

Figure 1

Changes in CRP and TNF-α levels for the two patient groups. Note: In the figure blue indicates the control group, red indicates the observation group, ns is not statistically significant, ** indicates P < 0.001, T0 indicates before treatment, T4w is at 4 weeks of treatment, and T12w is at 12 weeks of treatment. (a) Change in CRP levels and (b) change in TNF-α levels.

Figure 2

Changes in IL-6 and Fib levels between the two groups. Note: In the figure, blue indicates the control group, red indicates the observation group, ns means not statistically significant, ns indicates P > 0.05, * indicates P < 0.01, ** indicates P < 0.001, T0 is before treatment, and T12w is for 12 weeks of treatment. (a) Changes in IL-6 levels and (b) Changes in Fib levels.

Figure 3

Comparison of changes in indicators related to exercise tolerance between the two groups. Note: In the figure, blue indicates the control group, red indicates the observation group, ns indicates that the comparison between groups is not statistically significant, ns indicates P > 0.05, * indicates P < 0.01, ** indicates P < 0.001, and straight lines and dotted lines indicate the change trend among the three time points of the two groups. (a) 6MWT, (b) AT, (c) VO_2max, and (d) ED.