Clinical Geriatrics

This is the seventh and final article in the series on cardiovascular issues in the older adult. The sixth article in the series, “Understanding Hypertension and its Treatment in Elders,” was published in the November 2011 issue of  Clinical Geriatrics and can be accessed online at www.clinicalgeriatrics.com/articles/Understanding-Hypertension-and-its-Treatment-Elders.

It is estimated that more than 5.7 million adults in the United States are living with heart failure (HF).¹ HF is a syndrome that primarily affects the elderly, with nearly 75% of HF cases diagnosed in individuals older than 65 years,² the most rapidly expanding population cohort in the United States.³

Data published in 1993 from the Framingham Heart Study demonstrated a positive correlation between age and HF prevalence, ranging from 8 cases per 1000 persons for both men and women aged 50 to 59 years to 66 cases per 1000 persons for men and 79 cases per 1000 persons for women among individuals in their eighth decade of life.⁴ These rates may be even higher today, with Curtis and associates⁵ reporting in 2008 that the overall prevalence of HF in Medicare beneficiaries 65 years and older increased from approximately 90 cases per 1000 persons in 1994 to 120 cases per 1000 persons in 2003. The annual incidence of HF in those 65 years and older is said to approach 10 cases per 1000 persons, but data are conflicting as to whether the true incidence of HF is also on the rise.⁶ Curtis and colleagues⁵ found the incidence of HF in this demographic actually declined slightly between 1994 and 2003, largely due to decreased rates among adults 75 years and older.

Although data regarding the incidence and prevalence of HF among elders may be inconsistent, the condition clearly remains a significant concern. Given that an estimated 20% of the US population will be 65 years and older by 2050,⁷ the societal impact of HF cannot be understated. This review highlights clinically relevant aspects in the comprehensive management of the elderly patient with HF.

Risk Factors for Heart Failure

Modifiable and nonmodifiable factors increase an individual’s risk of developing HF (Table 1), the end stage on a pathway that is similar among various cardiovascular ailments, including valvular heart disease, arrhythmias, ischemic heart disease, and systemic hypertension (HTN). Age is the strongest predictor of one’s risk of HF. This nonmodifiable risk factor is associated with many pathophysiological changes, such as arterial stiffening and myocardial fibrosis, known to contribute to the development of the HF phenotype.

Advancing age is associated with higher rates of HTN and coronary artery disease, the two most potent modifiable risk factors for the development of HF.⁸ The critical importance of HTN in the pathogenesis of HF cannot be underestimated. A patient whose blood pressure is ≥160/100 mm Hg has nearly double the lifetime risk of developing HF than one whose blood pressure is <140/90 mm Hg.⁶

The elderly are less capable of favorable arterial remodeling and less able to tolerate cardiovascular disease. As a result, they are significantly more likely than younger adults to develop HF following myocardial infarction.⁹

The Spectrum of Heart Failure

The clinical spectrum of HF is heterogeneous, and signs and symptoms vary greatly between patients. Symptoms such as fatigue, dyspnea, and exercise intolerance may be misattributed to natural aging, deconditioning, a pulmonary process, or another disease entity. It is critical for physicians to maintain a high index of suspicion for HF and to know the signs and symptoms of venous congestion and impaired tissue perfusion.

Systolic HF (SHF; or systolic cardiac dysfunction) and HF with preserved ejection fraction (HFpEF) present similarly and occur with similar frequency, although the prevalence of HFpEF overtakes that of SHF in the 70 years and older demographic.¹⁰ SHF occurs when the heart muscle contracts with too little force, causing less oxygen-rich blood to be pumped throughout the body. Patients who have HFpEF suffer from underlying venous congestion and dyspnea with exertion due to impaired left ventricular (LV) relaxation, which renders them unable to accommodate increased blood flow upon activity. Differentiating between SHF and HFpEF requires cardiac imaging.

Establishing a diagnosis of HFpEF is challenging, and multiple definitions of this syndrome have been proposed. Most simply, HFpEF is defined as a signs and symptoms of HF in a patient who has a normal left ventricular ejection fraction (LVEF) on echocardiography.¹¹ The European Society of Cardiology favors a more rigorous definition that includes signs and symptoms of HF; LVEF ≥50%; and invasive hemodynamic, echocardiographic, or natriuretic peptide evidence of elevated filling pressures.¹² Patients 75 years and older have the highest prevalence of HFpEF, and their overall prognosis is similar to that for same-age patients with SHF.¹⁰ When HFpEF occurs in octogenarians, the prognosis is quite poor, as demonstrated by a study that found more than two-thirds of patients in this age group died within 5 years of diagnosis.¹³ 

HTN is common in patients with HFpEF, affecting about 50% of this population.¹⁴ The outcomes of patients with concomitant HTN and HFpEF are no better than outcomes for patients with HFpEF stemming from other etiologies, such as valvular heart disease.¹⁵ Cognitive impairment and renal insufficiency are poor prognostic findings in HFpEF.

The modes of death differ in HFpEF compared with SHF and are often related to noncardiac etiologies, including cancer, renal failure, and infections.¹⁶ Although survival for SHF has improved, mortality curves associated with HFpEF remain unchanged. Irrespective of the type of HF, a multidisciplinary approach to the care of HF patients is critical to their overall survival.