Original ArticleAcute admissions to medical departments in Denmark: Diagnoses and patient characteristics
Introduction
Acute medical patients comprise a high proportion of hospitalized patients, and they often present with complex problems and multiple chronic conditions [1], [2]. Despite extensive research on individual diseases, population-based knowledge about reasons for acute medical admissions remains limited [3], [4], [5].
Two European studies have reported that cardiovascular diseases are the leading causes for admissions to departments of internal medicine [3], [4]. However, both studies lacked detailed information on comorbidity, age, and gender according to diagnostic groups. The non-specific diagnoses from the Z-chapter of the International Classification of Diseases 10th edition (ICD-10) have been found to have a surprisingly high prevalence among acute admissions [6], [7], [8]. This reflects failure to classify the patients in specific diagnostic groups or failure to meet the patients' diagnostic or consultative needs.
Currently, services provided by inpatient medical departments face the challenge of demographic change. As the population ages, the prevalence of multiple chronic conditions is increasing [1], [9]. Knowledge about reasons for acute medical admissions and associated comorbidity levels, age, and gender is important both for physicians in departments of internal medicine and acute medical admission units and for healthcare planners.
We therefore conducted a population-based observational study of patients with acute admissions to inpatient medical departments in Denmark during 2010. We examined the primary diagnostic groups, Charlson Comorbidity Index (CCI) scores, age, and gender. In addition, we determined the source of admission, the length of hospital stay, and the distribution of individual conditions in the CCI, according to the primary diagnostic groups.
Section snippets
Study setting
We conducted this population-based observational study in Denmark using the Danish National Registry of Patients (DNRP), a national healthcare registry covering all hospitals [10]. Every Danish citizen is assigned a unique personal identification number at birth or immigration (CPR number), with embedded information on birth date and sex. These identifiers permit unambiguous individual-level linkage among all Danish population-based registries.
The Danish population (5,535,000 million people as
Gender and age
We identified 264,265 patients admitted acutely to the 178 medical departments in Denmark in 2010. While the overall study population included 51.3% females (Table 1), gender distribution varied among the diagnostic groups, for example with male predominance in mental disorders (59.0%) and cardiovascular diseases (55.3%), and female predominance in diseases of the musculoskeletal system and connective tissue disorders (57.8%) and hematological diseases (57.4%) (Table 2).
The median age of the
Key findings
In this population-based observational study, we found that two-thirds of the patients admitted acutely to the medical departments had one of the following four main reasons for admission: cardiovascular diseases, non-specific Z-diagnoses, infectious diseases, and non-specific R-diagnoses. The finding of high proportion of patients with non-specific diagnoses, particularly in patients with chronic diseases, is striking. In addition, we found considerable disparity in age, gender and chronic
Learning points
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In this large nationwide study describing the main reasons for acute admission to medical departments we found a strikingly high proportion of patients with non-specific diagnoses, particularly in patients with chronic diseases.
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Complications to chronic diseases are probably a common reason for admission, as we found a considerable overlap between the patients' chronic diseases and reason for admission.
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There were a considerable disparity in age, gender and chronic disease distribution according
Financial support
The study was supported by the Clinical Epidemiological Research Foundation, Denmark, and the Aarhus University Research Foundation, Denmark.
Contributors
BV-H, AHR, HTS, and CFC contributed to the study conception, design, and the interpretation of data. BV-H, AHR, HTS, and CFC were responsible for the acquisition of data. BV-H analyzed and drafted the manuscript. All authors critically revised the manuscript and approved the final version.
Conflict of interest statement
We wish to confirm that there are no known conflicts of interest associated with this publication and there has been no significant financial support for this work that could have influenced its outcome.
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