In 2013, American estimates indicated that there were 5.1 million people suffering from heart failure (HF). Worldwide, it is estimates that 23 million people are suffering from HF. The methodologies used to determine the prevalence of HF is based upon the known signs and symptoms of HF. The prevalence of HF and LV dysfunction has been known to increase with age. Specifically, the prevalence of HF for men aged 50-59 years is 8 per 1000 increased to 66 per 1000 for men ages 80-89 years. For women, there was an increase from 8 to 79 incidents per 1000 between the same age ranges. Further, there is a higher prevalence of HF in African American populations than white populations. There has also been an increase in the prevalence of heart failure over time, with studies indicating that there has been a 1/1000 and 0.9/1000 increase for men and women respectively between 1989 and 1999. The aging population is a significant contributor to this figure. Further, advance in early intervention for hypertension and valvular and coronary disease is resulting in later development of heart failure. By the year 2040, in the United States, it is expected that there will be 772,000 new cases of heart failure. These trends need to interpreted cautiously as there are many other factors such as new diagnostic methodology, increased awareness and changes to the prevalence of comorbidities that may affect the validity of the trends. Heart failure in hospitalised patients is often due to coexistent diseases.
PRESERVED SYSTOLIC FUNCTION
It is now thought that heart failure will often occur with normal LV systolic function, and presumably diastolic dysfunction. Diastolic dysfunction is thought to occur in 40-60% of patients with heart failure. The incidence of heart failure increases with age. The incidence rise more rapidly in women than in men, which sees the incidence double over each successive decade of life. Due to the balance between increase in risk with age and decrease in life expectancy with older age, it is expected that the lifetime risk of developing heart failure for individuals above 40 years of age is 20%. Older adults trends regarding age-adjusted heart failure incidence is unclear as 4 current studies have obtained inconsistent conclusions. More research in this area therefore needs to be conducted.