2.3 | Procedures
The day of concomitant diagnosis of liver cirrhosis and diabetes was
defined as the comorbid date. Persons who underwent insulin therapy for
at least 28 days after the comorbid date were defined as insulin users,
and those who never took insulin during the whole study period were
defined as insulin nonusers. We defined the first date of insulin use as
the index date. Variables considered as potential confounders in this
study included age, sex, age at the diagnosis of diabetes, the duration
of diabetes, antihypertensive and antidiabetic medications, statins, and
aspirin. Comorbidities status before the index date included HCV
(ICD-9-CM codes 070.41, 070.44, 070.51, 070.54, 070.70, 070.71, and
V02.62) and HBV infections (ICD-9-CM codes 070.2, 070.3, and V02.61). We
also calculated the Charlson comorbidity index (CCI) [15] and
Diabetes Complication Severity Index (DCSI) scores [16] to assess
the severity of diabetes.