Author information
1
1Asian Liver Center, Department of Surgery, Stanford University School of Medicine, 780 Welch Road, CJ130D, Palo Alto, CA 94304 USA.
2
2Division of Gastroenterology and Hepatology, Department of Medicine, Stanford University Medical Center, Palo Alto, CA USA.
3
San Jose Gastroenterology, San Jose, CA USA.
4
Palo Alto Medical Foundation, Mountain View, CA USA.
5
Chinese Hospital, San Francisco, CA USA.
6
6Stanford Prevention Research Center, Department of Medicine and Stanford Cancer Institute, Stanford University School of Medicine, Palo Alto, CA USA.
Abstract
BACKGROUND:
In the United States, the highest burden of chronic hepatitis B (CHB) and CHB-related liver cancer is in the state of California, primarily in the San Francisco (SF) Bay and Los Angeles (LA) areas. The aim of this study was to estimate county-specific hepatitis B surface antigen (HBsAg) prevalence and quantify CHB cases by age, race/ethnicity, nativity, and disease activity status.
METHODS:
Twelve counties in SF Bay Area and three large counties in LA area were included for this analysis. Race/ethnicity-specific prevalence of HBsAg for each county and the state of California as a whole, was estimated by including prevalence data from the National Health and Nutrition Examination Survey and various studies that estimated HBsAg prevalence in US and foreign-born Asian Pacific Islanders, Hispanic, and Black populations. In addition, clinical data of 2000 consecutive CHB patients (collected between 2009 and 2014) from a large clinical consortium in the SF Bay area were used to calculate the age-specific disease burden.
RESULTS:
Of the 15 counties analyzed, SF had the highest HBsAg prevalence (1.78%), followed by Santa Clara (1.63%) and Alameda (1.45%). The majority of CHB cases were estimated to be in LA County (83,770), followed by Santa Clara (31,273), and Alameda (23,764). Among the CHB cases, 12.7% is active HBeAg positive, 24.2% is active HBeAg negative, and 10.6% has cirrhosis.
CONCLUSION:
This study confirms and quantifies the current burden of CHB in high endemic counties in the state of California using population-level estimates combined with clinical data including those from the community.