Low incidence of hospitalization with gallbladder disease among blacks in the United States.

Low rates of gallbladder disease among blacks have been reported but not systematically studied. The authors investigated the rate of hospitalization with a diagnosis of gallbladder disease in the follow-up in 1982-1984 of the first National Health and Nutrition Examination Survey, a population-based study conducted across the United States in 1971-1975. Based on hospital discharge diagnoses of gallbladder disease, 368 cases were identified for the period 1971-1984 among 10,551 persons, aged 25-74 years, who denied gallbladder disease at the baseline examination. The crude incidence of gallbladder disease per 1,000 person-years was 2.59 for white men, 1.45 for black men, 4.09 for white women, and 2.35 for black women. Controlling for obesity, parity, ethanol consumption, use of diuretics, use of oral contraceptives, and two indicators of socioeconomic status, the authors found that the hazard rate of hospitalization with gallbladder disease increased with age for white women and decreased for black women. The hazard ratio for black women compared with white women at 30 years of age was 0.71 with a 95% confidence interval of 0.52-0.96, but at age 70, it was 0.18 with a 95% confidence interval of 0.09-0.37. For women, obesity and parity were important risk factors for gallbladder disease (p less than or equal to 0.001), and the use of diuretics was marginally associated (p = 0.08). Black men compared with white men had a hazard rate of gallbladder disease of 0.53 with a 95% confidence interval of 0.24-1.16. For men, increasing age was related to gallbladder disease (p less than 0.001), and obesity was weakly related (p = 0.06). The black/white hazard ratios decreased further when controlling for socioeconomic status, persisted if the study population was limited to those hospitalized during follow-up, and increased slightly for cases with an acute complication of gallbladder disease. Thus, differential access to medical care may not explain the lower rate among blacks.