Table 3.
Sensitivity analyses of the risk of tuberculosis (TB) and herpes zoster in comparison groups
| Compared groups | Events number | Drug‐free group as reference | Nonstatin users as reference | ||
|---|---|---|---|---|---|
| Adjusted HR (95% CI)a | P value | Adjusted HR (95% CI)a | P value | ||
| Sensitivity analyses for the primary outcome (TB) | |||||
| Drug‐discontinuation date as an additional end point | |||||
| Drug‐free (n = 22 316) | 426 | 1 | 0.830 (0.516–1.337) | .445 | |
| Statin users (n = 17 696) | 38 | 0.602 (0.430–0.842) | .003 | 0.500 (0.285–0.878) | .016 |
| Nonstatin users (n = 5327) | 18 | 1.204 (0.748–1.939) | .445 | 1 | |
| Adjustment for lipid profiles monitoring frequencyb | |||||
| Drug‐free (n = 22 316) | 426 | 1 | 1.179 (0.809–1.718) | .390 | |
| Statin users (n = 17 696) | 81 | 0.558 (0.429–0.725) | <.001 | 0.658 (0.436–0.993) | .046 |
| Nonstatin users (n = 5327) | 32 | 0.848 (0.582–1.235) | .390 | 1 | |
| Adjustment for use of comedications at baselinec | |||||
| Drug‐free (n = 22 316) | 426 | 1 | 1.199 (0.832–1.728) | .331 | |
| Statin users (n = 17 696) | 81 | 0.551 (0.431–0.705) | <.001 | 0.661 (0.438–0.997) | .049 |
| Nonstatin users (n = 5327) | 32 | 0.834 (0.579–1.202) | .331 | 1 | |
| Sensitivity analyses for secondary outcome (herpes zoster) | |||||
| Drug‐discontinuation date as an additional end point | |||||
| Drug‐free (n = 22 639) | 1209 | 1 | 1.061 (0.773–1.456) | .716 | |
| Statin users (n = 17 433) | 284 | 1.288 (1.129–1.469) | <.001 | 1.366 (0.980–1.904) | .066 |
| Nonstatin users (n = 5267) | 40 | 0.943 (0.687–1.294) | .716 | 1 | |
| Accounting for all herpes zoster events (before and after TB) | |||||
| Drug‐free (n = 22 639) | 1224 | 1 | 1.024 (0.847–1.239) | .806 | |
| Statin users (n = 17 433) | 651 | 1.202 (1.089–1.327) | <.001 | 1.231 (1.012–1.499) | .038 |
| Nonstatin users (n = 5267) | 119 | 0.976 (0.807–1.181) | .806 | 1 | |
CI indicates confidence intervals; HR, hazard ratio.
In the Cox model with time‐dependent covariates, person‐years of statin users and nonstatin users were coded as drug‐free before initiation of lipid lowering agents and then recoded as statin users or nonstatin users after drug initiation. The adjusted cofactors in the models were those listed in the footnote b of Table 2.
The lipid profiles monitoring frequency at baseline referred to the sum of numbers of monitoring lipid profiles (including total cholesterol, high‐density lipoprotein, and triglyceride) within the first post‐treatment 6 months in statin users and nonstatin users, and within the initial 6 months after diabetes diagnosis in drug‐free group.
The additional comedication entered into the model were sulfonylurea, insulin, dipeptidyl peptidase‐4 inhibitor and systemic steroid use at baseline.