Julia Uhanova

OBJECTIVE: To determine whether rates of physician visits for ambulatory care sensitive (ACS) conditions are lower for people of low-socioeconomic status than of high-socioeconomic status in an urban population with universal health care coverage. DATA SOURCES/STUDY SETTING: Physician claims and hospital discharge abstracts from fiscal years 1998 to 2001 for urban residents of Manitoba, Canada. The 1996 Canadian Census public use database provided neighborhood household income information. The study included all continuously enrolled urban residents in the Manitoba Health Services Insurance Plan. STUDY DESIGN: Twelve ACS conditions definable using 3-digit ICD-9-CM codes permitted cross-sectional and longitudinal comparison of ambulatory visits and hospitalizations. Neighborhood household income data provided a measure of socioeconomic status. DATA COLLECTION/EXTRACTION METHODS: Files were extracted from administrative data housed at the Manitoba Centre for Health Policy. PRINCIPAL FINDINGS: All conditions showed a socioeconomic gradient with residents of the lowest income neighborhoods having both more visits and more hospitalizations than their counterparts in higher income areas. Six of nine conditions with a sufficient N showed individuals living in the lowest income neighborhoods to have significantly more ambulatory visits before hospitalization for an ACS condition than did those in the most affluent neighborhoods. Many conditions showed a gradient in rate of hospitalization even after controlling for the number of ambulatory care visits. CONCLUSIONS: In the Canadian universal health care plan, the poor have reasonable access to ambulatory care for ACS conditions. Ambulatory care may be more effective in preventing hospitalizations among relatively affluent individuals than among the less well off.

Hepatitis B virus (HBV) infections continue to occur in adult hemodialysis units. A possible contributing factor is the presence of occult HBV (serum hepatitis B surface antigen [HBsAg] negative but HBV DNA positive). Two hundred forty-one adult hemodialysis patients were screened for occult HBV. HBV DNA testing was performed by real-time polymerase chain reaction (PCR) with 2 independent primer sets (core promoter and surface). Two (0.8%) of the 241 patients were HBsAg positive. Of the remaining 239 HBsAg-negative patients, 9 (3.8%) were HBV DNA positive. Viral loads in these individuals were low (10(2)-10(4) viral copies/mL). Seven of the 9 (78%) were nt 587 mutation (sG145R mutant) positive. Demographic, biochemical, and HBV serological testing did not help to identify those with occult HBV. In conclusion, the prevalence of occult HBV in adult hemodialysis patients in this North American urban center is approximately 4 to 5 times higher than standard HBsAg testing would suggest. The majority of these infections are associated with low viral loads and a high prevalence of the sG145R mutant. Finally, the demographic, biochemical, and/or serological features of HBV DNA-positive subjects do not distinguish these individuals from the remainder of the dialysis patient population.

INTRODUCTION AND OBJECTIVES: Hepatocellular liver injury is characterized by elevations in serum alanine (ALT) and aspartate (AST) aminotransferases while cholestasis is associated with elevated serum alkaline phosphatase (ALP) levels. When both sets of enzymes are elevated, distinguishing between the two patterns of liver disease can be difficult. The aim of this study was to document the predicted ranges of serum ALP values in patients with hepatocellular liver injury and ALT or AST values in patients with cholestasis. MATERIALS AND METHODS: Liver enzyme levels were documented in adult patients with various types and degrees of hepatocellular (non-alcoholic fatty liver disease, hepatitis B and C, alcohol and autoimmune hepatitis) and cholestatic (primary biliary cholangitis and primary sclerosing cholangitis) disease. RESULTS: In 5167 hepatocellular disease patients with ALT (or AST) values that were normal, 1-5×, 5-10× or >10× elevated, median (95% CI) serum ALP levels were 0.64 (0.62-0.66), 0.72 (0.71-0.73), 0.80 (0.77-0.82) and 1.15 (1.0-1.22) fold elevated respectively. In 252 cholestatic patients with ALP values that were normal, 1-5× or >5× elevated, serum ALT (or AST) values were 1.13 (0.93-1.63), 2.47 (2.13-2.70) and 4.57 (3.27-5.63) fold elevated respectively. In 56 patients with concurrent diseases, ALP levels were beyond predicted values for their hepatitis in 38 (68%) and ALT (or AST) values beyond predicted values for their cholestatic disorder in 24 (43%). CONCLUSIONS: These data provide health care providers with predicted ranges of liver enzymes in patients with hepatocellular or cholestatic liver disease and may thereby help to identify patients with concurrent forms of liver disease.