Background
Among patients with multiple chronic conditions, there is increasing appreciation of the complex interrelatedness of diseases.
Previous studies have focused on the prevalence and economic burden associated with multiple chronic conditions, much less
is known about the mortality rate associated with specific combinations of multiple diseases.
Objective
Measure the mortality rate in combinations of 11 chronic conditions.
Design
Cohort study of veteran health care users.
Participants
Veterans between 55 and 64 years that used Veterans Health Administration health care services between October 1999 and September
2000.
Measurements
Patients were identified as having one or more of the following: COPD, diabetes, hypertension, rheumatoid arthritis, osteoarthritis,
asthma, depression, ischemic heart disease, dementia, stroke, and cancer. Mutually exclusive combinations of disease based
on these conditions were created, and 5-year mortality rates were determined.
Results
There were 741,847 persons included. The number in each group by a count of conditions was: none = 217,944 (29.34%); 1 = 221,111
(29.8%); 2 = 175,228 (23.6%); 3 = 86,447 (11.7%); and 4+ = 41,117 (5.5%). The 5-year mortality rate by the number of conditions
was: none = 4.1%; 1 = 6.0%; 2 = 7.8%; 3 = 11.2%; 4+ = 16.7%. Among combinations with the same number of conditions, there
was significant variability in mortality rates.
Conclusions
Patients with multiple chronic conditions have higher mortality rates. Because there was significant variation in mortality
across clusters with the same number of conditions, when studying patients with multiple coexisting illnesses, it is important
to understand not only that several conditions may be present but that specific conditions can differentially impact the risk
of mortality.
KEY WORDS chronic conditions - coexistant conditions - mortality - veterans