Congestive heart failure: Change in risk factors, comorbidity and age at the time of first hospitalization. Follow-up of a population cohort between 2011 and 2016 using real life data

Abstract

Introduction The current health information systems offer an opportunity to implement advanced methodology to generate evidence within the context of the healthcare activity. This evidence could complement that of the clinical trials, often challenged due to poor external validity. This use of real world data (RWD) has also its limitations, mainly due to selection bias, confusion, and the comprehensiveness and quality of the data itself. Congestive heart failure (CHF) is one of the most prevalent and lethal diseases in Europe. It is currently increasing in frequency and complexity and, due to the aging of the population, its characteristics at the onset are also changing. Our objectives are to describe the changes over time of patients with a first hospitalization by CHF regarding age, the risk factors associated to the disease and the comorbidity, including Charlson index. Methods (1) Subjects: persons of 40 years or older, with a first hospitalization by CHF in the public hospitals of the Basque Country (population 2,100,00). (2) Sources of data: business Intelligence Platform, which includes all the information collected in hospitals, primary care, emergency rooms, day-hospitals of the Basque Health Service. Also, mortality data and socioeconomic status (SES) data provided by the Basque Health Department. The variables we looked for were: age, sex, SES, risk factors, comorbidity. (3) Analysis: linear regression, temporal trends. Analyses were conducted using the R version 3.3.2. Results (1) Demographic factors: between 2011 and 2015, the incidence of the disease has increased in both men (from 2.87 to 3.06 cases/1000 persons/year) and women (2.55 to 2.85 cases/1000 persons/year). This trend, however, almost disappears after standardizing by age. In fact, the average age is also increasing in men (76.6 ± 10.9 in 2011 to 78.1 ± 8.0 in 2015) and in women (82.2 ± 9.2 to 83.2 ± 8.7). (2) Risk factors: according with the older age of the patients when they hospitalized for the first time, the prevalence of accompanying diseases and other risk factors is also increasing. During the 5 years covered by this study, a monotonic increase has been observed between 2011 and 2015 in the prevalence of: hyperlipidemia (from 42.8% to 50.2%), heart valve disorders (32.8% to 43.8%), chronic renal failure (25.6% to 31.3%), degenerative eye problems (23.8% to 29.8%), pulmonary heart disease (16.4% to 24.9%), malnutrition-obesity (18.0% to 23.4%). (3) Charlson index: comorbidity, as measured by the Charlson index, increased from 3.4 ± 2.1 to 3.7 ± 2.2 in men, and from 2.7 ± 1.8 to 2.9 ± 1.8 in women. Conclusions In agreement with the most recent studies, ours has also detected a change towards older and more complex CHF patients over the last five years. Another aspect to highlight is the opportunity offered by the RWD to monitor the process and to do clinical epidemiology. A limitation is the completeness and quality of the information registered. Another one, a possible tendency to comorbidity overdiagnosis, due to a higher intensity in the diagnostic effort.