回顾性队列研究

示意意见 · 非真实审稿意见

The authors defined exposure from the date of first prescription, but the follow-up time appears to begin at cohort entry, which may predate the index date. This immortal time — during which the outcome cannot occur — inflates the time at risk in the exposed group and biases the hazard ratio toward a protective effect.

预防策略：在方法节明确说明"暴露起点（index date）= 首次满足暴露定义的时间点，随访计时起点 = index date"。在方法节单独一段说明 immortal time 的处理方式，并在数据标准化阶段用 SQL/R 代码核查每例患者的 index date ≤ 随访起点。流行病学观察性研究报告规范（STROBE） 研究对象流程图（基于常规收集健康数据时参照 常规收集健康数据观察性研究报告规范（RECORD））中的时间轴标注应与方法节文字一致。

示意意见 · 非真实审稿意见

After propensity score matching, the authors claim the two groups are comparable, but no standardized mean differences (SMD) are reported for individual covariates. It is unclear whether residual imbalance remains after matching, especially for key confounders such as disease severity.

预防策略：在表 1 中为每个协变量报告配对前后的 SMD，并以 Love plot 作为附件直观展示。若某关键变量 SMD 配对后仍 >0.1，在方法节说明原因（如该变量分布极端偏斜）和补充分析。IPTW 替代分析作为敏感性结果在附件中提供，正文引用 "consistent with primary PSM analysis"。

示意意见 · 非真实审稿意见

The primary outcome is cardiovascular mortality. However, all-cause mortality is a competing event that was not accounted for. Standard Cox regression in this setting may overestimate the cumulative incidence of the primary outcome, particularly in older populations with high competing event rates.

预防策略：在结局定义部分列出所有潜在竞争事件（如全因死亡、出院后失访），并说明主分析是否采用竞争风险模型（Fine-Gray 或 cause-specific Cox）。若使用标准 Cox，在讨论局限性中说明在本研究人群中竞争事件率低（提供数字支撑），或在敏感性分析中追加竞争风险模型结果对比。