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Findings (continued)

What Are the Most Common Reasons for Hospitalization for Various Age Groups?

  • Depression is one of the top 10 conditions for children and adolescents 1 to 17 years of age and adults 18-44.
  • For the group 18 to 44 years of age, 9 of the top 10 reasons for hospitalization pertain to pregnancy and delivery. When these conditions are excluded, 4 of the top 10 conditions relate to mental illness or substance abuse.
  • For all age groups 45 and older, hardening of the arteries, heart attack, and congestive heart failure are among the top 10 reasons for hospitalization.
  • Some conditions, such as pneumonia, appear in the top 10 for several age groups.
  • Some conditions are unique to particular age groups. Hip fracture and septicemia (blood infection) are among the top 10 conditions only for patients ages 80 or older.

Table 4. Most Common Reasons for Hospitalization by Age Group

Top 10 diagnoses* by age group Years
<1 1-17 18-44 45-64 65-79 80+
Number of discharges (in thousands)
Infants born in the hospital 3,844          
Acute bronchitis 110          
Other perinatal conditions 57          
Hemolytic jaundice and perinatal jaundice 34          
Other viral infections 29          
Prematurity (short gestation) and low birthweight 23          
Urinary tract infection 21         127
Other upper respiratory infections 20 42        
Fluid and electrolyte disorders 24 65       135
Pneumonia 57 138 133 203 374 353
Appendicitis   67        
Epilepsy   47        
Intestinal infection   38        
Noninfectious gastroenteritis   38        
Asthma   161 112      
Depression (affective disorder)   57 307      
Intervertebral disc disorders and other back problems   38 190      
Schizophrenia and related disorders     171      
Substance-related mental disorders     147      
Alcohol-related mental disorders     142      
Benign neoplasm of the uterus     130      
Gall bladder (bilary tract) disease     146 136    
Nonspecific chest pain     111 246    
Degenerative joint disease of spine (spondylosis)       194    
Diabetes mellitus with complications       133    
Chronic obstructive lung disease
(emphysema or chronic bronchitis)
      151 269  
Complication of device, implant or graft       145 182  
Hardening of the arteries of the heart
(coronary atherosclerosis)
      535 636 189
Heart attack (acute myocardial infarction)       247 300 156
Congestive heart failure       180 426 374
Osteoarthritis         250  
Rehabilitation care         183  
Stroke (acute cerebrovascular disease)         269 214
Irregular heartbeat (cardiac dysrhythmia)         258 152
Hip fracture           205
Blood infection (septicemia)           136

* Excludes pregnancy-related conditions.

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Do Patients in the Hospital Have Medical Problems in Addition to the Main Reason for Admission?

  • Comorbidities2 are coexisting medical problems that are listed as secondary diagnoses (not principal diagnoses, or the main reason for admission). Comorbidities can make a hospital stay more expensive and complicated. Conditions are designated as comorbidities if they are not directly related to the principal diagnosis and are likely to have originated prior to the hospital stay.
  • About 54 percent of hospitalized patients have at least one comorbidity.
  • Patients can have more than one comorbidity; about 1/3 of patients have two or more.

Select Figure 7 (15 KB), Comorbidities Among Hospitalized Patients.


What Are the Most Common Comorbdities?

  • About 1 in 5 patients has hypertension in addition to the principal diagnosis.
  • The second most common comorbidity—fluid and electrolyte disorders—is associated with many conditions and may be a marker for the severity of the principal diagnosis.

Table 5. Top 10 Comorbidities

Top 10 comorbidities Total number of cases with each comorbidity (in thousands) Percent of all discharges
1. Hypertension 7,231 20.4
2. Fluid and electrolyte disorders 4.798 13.6
3. Chronic obstructive lung disease (emphysema or chronic bronchitis) 3.843 10.9
4. Diabetes mellitus 3,375 9.5
5. Irregular heartbeat (cardiac dysrhythmia) 2,398 6.8
6. Anemias 2,164 6.1
7. Solid tumor without metastasis 2,021 5.7
8. Congestive heart failure 1,880 5.3
9. Hypothyroidism 1,375 3.9
10. Hardening of the arteries (peripheral vascular disease) 1,045 3.0

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