Acute coronary syndromes in elderly patients – differences in clinical presentation, ECG findings and access to medical care 

Background

Clinicians are becoming aware of the heterogeneity of clinical presentation, response to treatment as well as prognostication in elderly patients with acute coronary syndromes (ACS). This group of patients however remains undertreated especially in terms of aggressive interventional procedures for fear of adverse events and in the belief that the benefits are less important than in younger patients.
This article summarises the differences in risk factors, ECG findings and clinical presentations in elderly verses younger patients presenting with ACS.

I – The elderly present different risk factors and symptoms and take more time to seek care.

    1) Risk factors : more history of CAD, diabetes and hypertension, women and depression found in patients above 75 years of age.

Data from the Euro Heart Survey on ACS showed that patients under the age of 75 have a different risk profile than those older than 75 years of age. The younger patients presented more often with obesity, familial history of CAD and were smokers, whereas patients above 75 years of age more frequently had a history of coronary heart disease, diabetes and hypertension.  They were more often women [3] [4]. Importantly, depression is very common in the elderly, particularly in those living alone and this can condition may lead to noncompliance with the treatment regimen as well as cardiac rehabilitation [5].   

    2) Symptoms at presentation : less typical anginal chest pain, more heart failure in patients above 85 years of age.

The absence of typical anginal chest pain in patients with ACS may be associated with a misdiagnosis or a delayed diagnosis of myocardial infarction (MI). In fact, myocardial infarction goes three times more often unrecognised in patients > 85 years in comparison to younger subjects [5] [6] [7]. The NRMI registry showed that in patients older than 85 years, typical chest pain was present in only 40% of cases in comparison to 77% in patients < 65 years presenting with STEMI [8]. The GRACE Investigators also reported that in older patients the absence of typical chest pain was significantly more frequent than in younger patients. On presentation, the elderly complained much more frequently of dyspnea, diaphoresis, nausea, vomiting and syncope. In older patients, the worsening of heart failure is a common manifestation of ACS [5] [9]. In general, the presence of signs and symptoms of heart failure increases significantly -  from 20 to 40% in elderly patients with ACS as shown in other registries [1] [5] [10].

    3) Delay in seeking medical care : Older patients wait longer before seeking medical care

Delay to the initiation of definite medical care in patients with ACS can worsen the outcome. Old age, female gender and low socioeconomic status are among the major factors associated with the delay of seeking medical care [12]. Older patients had significantly longer time-lapses between the onset of symptoms and hospital admission (difference > 1.5 hours between younger than 65 and older than 75 years). This suggests that the elderly wait markedly longer before seeking medical care [4]. 

II – Cardiogist undertreat the elderly.

    1) Initial EGG, longer to receive and more often undetermined.

According to the guidelines, ECGs should be obtained in every patient with chest pain within the 10 minutes that follow presentation. The CRUSADE trial revealed a marked delay in obtaining the initial ECG in patients > 85 years as compared to younger patients [11]. The NRMI registry showed that non-diagnostic initial ECGs in elderly patients are twice as frequent as in younger patients [2] [8]. In patients with STEMI the typical chest pain coexisted with ST-segment elevation with decreasing frequency as the patients age increased and were present in 72% of patients =75years as compared to 90% of patients < 65 years. Similar observations were made in a group of NSTE ACS where typical chest pain and ST-segment depression were present in 83% of younger patients and in less than 68% of the older patients [4]. In addition, data from the EuroHeart ACS survey that included more than 10 000 patients demonstrated a significant increase of ACS of undetermined ECG in older patients (increase from 1.7 to 16%) [3]. 

    2. Differences in medical care and access to treatment : the elderly are less agressively treated.

Recent data from studies examining the implementation of guideline-recommended treatment strategies showed that the elderly, particularly, tend to be undertreated. Even after adjustment for their higher contraindications rate, the elderly remain less aggressively treated. In a large cohort of 169 079 Medicare beneficiaries  65 years referred for treatment of acute MI, the aspirin and reperfusion treatment were underused, in particular in women [13].

Also, according to PRAIS-UK study, heparin and statins are used less frequently in the elderly with ACS [14].

The problem is even more evident with regards to the use of early invasive strategy in ACS  [16] despite the fact that recent data support the implementation of early invasive strategy in patients with ACS, especially in groups with elevated cardiac biomarkers levels and ST-segment changes. Due to a high comorbidities rate, such as renal failure and generalised atherosclerosis, the elderly are often declined invasive treatment for fear of complications. A Large ACOS registry has shown that among the 1936 elderly patients (>75 years) with NSTEMI, the subgroup of younger patients with a lower risk profile is more often referred for early invasive treatment then those with a high risk, eg. cardiogenic shock, diabetes of renal failure.

This approach, however, leads to exclusion of patients who might have known a significantly higher risk reduction from an invasive approach. Invasive strategy is superior to medical therapy in terms of reduced in-hospital mortality (OR 0.55, 95% CI 0.35-0.86) and 1-year mortality (OR 0.56, 95% CI 0.38-0.81) [8] [17]. Elderly patients treated with PCI are considered a high-risk group. Even though patients older than 80 more often have multivessel coronary artery disease, severe target vessel calcifications, smaller vessel diameter and longer lesions, PCI can be performed safely with high procedural success rates (>97%) in this population [18].

III – The elderly, nevertheless, benefit from the trend towards a more frequent use of guidelines-recommended medications.

According to the World Health Organization 60 years of age is used to define the “elderly”, however most guidelines and clinical trials refer to the “elderly” as individuals older than 75 years. The Population of elderly patients is also underrepresented in clinical trials which serve as source of evidence-based data used subsequently for formulation of practice guidelines [1] [2].

Nevertheless there is increasing evidence supporting the use of guideline-recommended treatment strategies might already have started to change physicians’ approaches. The analysis of temporal trends in the treatment of 20 550 patients =65 years admitted with acute MI revealed improved quality of care and increased survival over the period of 1992-2001. At the same time the mean age of patients increased from 75.7 to 78.3 years, with a substantial number of patients over 85 years. Also a higher proportion of patients was taking aspirin, beta-blockers, statins and angiotensin-converting enzyme inhibitors before admission [19]. The data shows an encouraging trend towards more frequent use of guidelines-recommended medications.