Viral hepatitis is the inflammation of the liver caused by one of the five hepatotropic viruses, which are hepatitis A, hepatitis B, hepatitis C, hepatitis D and hepatitis E.
Besides these viruses, other viruses that can cause hepatitis are herpes simplex, Epstein-Barr virus, cytomegalovirus and virus causing yellow fever. However, the liver inflammation caused by these viruses is not termed as viral hepatitis The elderly are increasingly predisposed to the threat of developing viral hepatitis owing to the increase in life expectancy. Elderly people with viral hepatitis have high rates of mortality than their younger counterparts. Factors that contribute to viral hepatitis in the elderly are presence of co-morbid conditions, aging, environmental hepatotoxins and growing exposure to hepatotropic viruses.
AdvertisementAndres Carrion and colleagues published a paper in the American Journal of Gastroenterology regarding the increasing prevalence of viral hepatitis in the elderly.
The researchers stated in the paper, "The age-related decline of liver regeneration has been described in animal models in which the mitogenic capacity of hepatocytes is reduced with aging (up to 70% lower than in younger animals). This finding has also been recently corroborated in humans with significant reductions in liver regeneration noted in individuals older than 50 years compared with younger adults undergoing living donor liver transplantation."
Due to implementation of vaccination against hepatitis A virus (HAV) in children and adults, the prevalence of hepatitis A has declined considerably. However, the authors state that "The seroprevalence of anti-HAV immunoglobulin (Ig) G, a marker of prior infection with HAV, increases proportionally with age reflecting a cumulative risk of HAV infection throughout life."
It is noted that the severity of clinical cases of HAV in elderly people are reflected in high rates of mortality and hospitalization.
On the whole, the reasons for poor outcomes of HAV infection in the older population are multifactorial and related to high prevalence of co-morbid conditions, lowered regenerative capacity of liver and declining immune function especially cell-mediated immunity with increasing age.
The third National Health and Nutrition Examination Survey (NHANES III) revealed the prevalence of chronic hepatitis B virus (HBV) is 0.42% in the United States.
The paper also reported, "The NHANES (1999-2006) showed an overall seroprevalence of past/present HBV infection in the United States of 4.7%."
The clinical presentation of acute HBV infection is quite different in the elderly than the younger individuals. During an outbreak of acute hepatitis B infection, most of the affected elderly people were asymptomatic and only few of them presented with jaundice and symptoms such as nausea, vomiting and anorexia.
The paper revealed an important point-"The risk of progression to chronic hepatitis B is inversely related to age at the time of infection."
Immunization against HBV is advised for all elderly who are at the risk for infection especially in nursing and healthcare centers as these individuals are exposed to contamination with blood and other body fluids.
The prophylactic use of antiviral agents in HBV carriers irrespective of age is advised in case of initiation of immunosuppressive therapy. The commonly used drugs for short term treatment (≤12 months) are telbivudine and lamivudine and for long term treatment are entecavir and tenofovir.
The incidence of hepatitis C Virus (HCV) infection in the United States is declining, especially in the younger population.
In the elderly population, the possible risk factors for HCV infection are military services, tattoos, injection drug use, blood transfusions (prior to 1992), hemodialysis and employment as a health care worker. After making adjustments for alcohol intake, sex, diabetes, body mass index and HIV status, advancing age at the time of onset of infection is also an important factor associated with advanced hepatic fibrosis.
It is seen that older individuals have low acceptance of antiviral therapy, and low doses and discontinuation of antiviral therapy is quite common in elderly people as compared to younger generation.
The paper suggested, "Current practice guidelines recommend not withholding antiviral therapy based purely on advanced age but suggested that special attention should be paid to co-morbid conditions and tolerance for potential side effects."
The hepatitis E virus (HEV) is sporadic in USA while endemic and epidemic in Africa, Asia and Mexico.
Very limited data is available for HEV and exposure to HEV is rare. In elderly, it should be regarded as a potential etiology of acute hepatitis.
With increasing advancement in health care, an increase in elderly population is noticed across the globe. This elder population is exposed to high risk of acute and chronic liver complications and prevalence of high co-morbid conditions. Andres Carrion highlighted the need for broadening and revising the indications for immunization of the elderly against hepatitis A ands B to prevent these infections and protect the elderly against potential complications.
Viral Hepatitis in the Elderly; Andres Carrion et al; The American Journal of Gastroenterology 2012