Objective: Chronic disease comorbidities, on the rise in the U.S. and Virginia, represent a new challenge to the way medicine is practiced and prescribed. This descriptive study uses Virginia hospital discharge data to describe the prevalence and trends of chronic disease comorbidities present in the state's over-45 population during the years 2001 and 2004.Methods: Data collected by Virginia Health Information was utilized. Adults over the age of 45 years and who selected for race and location were included in this analysis, with an aggregate sample size of 813,336 (N=458,593 [2001]; N=364,743 [2004]). Pearson chi-square analyses determined significant sample population differences with respect to age, race, sex, location, number of diagnoses (up to 9) and number of chronic comorbid conditions (up to 7). Binary logistic regression predicted odds ratios (ORs) for these comorbid conditions across demographic variables. SPSS 13.0 was used for all analysis. Results: Chronic comorbidities and their component conditions increased in Virginia's inpatient population from 2001 to 2004. Chronic cardiovascular disease (CCV), chronic liver disease (CLV), chronic renal disease (CRN), chronic pulmonary disease (COP), and cerebrovascular degeneration (CCE) comorbidities all increased in diagnoses prevalence (0.3% -1.8%), while comorbid cancer (CCA) remained constant at 7.4% and comorbid diabetes (CDI) decreased 0.6%. Mean comorbid diagnoses increased with age. Demographic factors (race, sex, age and location) as well as certain constituent conditions were predictive of one or more comorbidities. Conclusions: In general, the findings of this report complement current chronic disease monitoring data for the Commonwealth of Virginia. While expected comorbidities did exist (e.g. obesity with diabetes), unpredicted findings such as the highly-comorbid "fluid and electrolyte disorders" or the highly-comorbid "deficiency anemias" were also noted.