Response to Wakasugi et al.
We thank Wakasugi et al., for their insights(1) regarding the rates of hip fracture among dialysis patients in Japan. Both theirs and our study highlights the substantial burden of fracture among dialysis patients relative to the general population, even after accounting for differences in case mix. The potential differences in the fracture rates reported by Wakasugi et al(2) compared to ours may be explained by a variety of factors, including differences in the study design and data collection.
In the DOPPS, information on hospital admissions is collected through data abstraction from the patient medical record by a study coordinator, who is typically a nurse. The validity of this approach is supported by the fact that clinical outcomes collected in the DOPPS have been comparable to those reported by national registries(3). Data collection by Wakasugi et al. were based on patient recall (patient questionnaire), which may have contributed to the differences in fracture rates.
Differences in the time period included for calculation may have also contributed, since even hip fracture rates in the Japanese general population varied substantially in reports from different time periods (4,5).
Given the significant clinical burden associated with fractures in this frail population, additional studies examining fracture incidence and burden in Japanese dialysis patients may be warranted.
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