Myocardial Infarction and Acute Cholecystitis: An Application of Sequence Symmetry Analysis

• Published in: Epidemiology (Cambridge, Mass.) Mass.), 2000-07, Vol.11 (4), p.446-449
• Main Author: Cher, Daniel J.
• Format: Article
• Language: English
• Subjects: Acute cholecystitis; Acute Disease; Adult; Aged; Aged, 80 and over; Biological and medical sciences; Cardiology. Vascular system; Cholecystitis - epidemiology; Cholecystitis - etiology; Confounding Factors (Epidemiology); Congestive heart failure; Coronary heart disease; Data Collection; Databases, Factual; Epidemiologic Methods; Epidemiology; Female; Gallstones; Gastroenterology. Liver. Pancreas. Abdomen; Heart; Hospital admissions; Hospitalization; Humans; Incidence; Liver. Biliary tract. Portal circulation. Exocrine pancreas; Male; Mathematical sequences; Medical sciences; Middle Aged; Myocardial infarction; Myocardial Infarction - complications; Other diseases. Semiology; Patient Discharge; Predisposing factors; Ratios; Retrospective Studies; Risk Assessment; Time windows
• ISSN: 1044-3983; 1531-5487
• DOI: 10.1097/00001648-200007000-00014

Using a statewide hospital discharge database and a novel epidemiology method, sequence symmetry analysis (Epidemiology. 1996;7:478-84), I examined the relative risk for hospital admission for acute cholecystitis after admission for myocardial infarction. In sequence symmetry analysis, the ratio of the number of subjects in a fixed population who experienced two events in a "causal" vs "noncausal" temporal sequence estimates the incidence rate ratio (IRR). Of 514 patients admitted for both myocardial infarction and acute cholecystitis during a 3-year window period, 295 were admitted for myocardial infarction first and 219 for acute cholecystitis first, yielding a null sequence-adjusted IRR of 1.45 [95% confidence interval (CI) = 1.28-1.64]. A similar analysis for a known relation (myocardial infarction→congestive heart failure, N = 27,850) showed the expected association [adjusted IRR = 1.92 (95% CI = 1.88-1.95)], whereas an analysis for a relation hypothesized not to be strong (congestive heart failure→acute cholecystitis, N = 775) showed only a small association [adjusted IRR = 1.16 (95% CI = 1.05-1.28)]. Subgroup analysis revealed time courses that supported each relation as causal. Hospitalization for myocardial infarction may increase the risk for subsequent hospitalization for acute cholecystitis.