Summary

Higher cutaneous melanin reduces vitamin D3 production. This may increase fracture risk. We found that cutaneous melanin density was associated with prevalent and short-term, but not long-term, incident fracture risk in older Caucasian adults. Melanin density either acts as a surrogate marker or its relationship with fracture changes with time.

Introduction

Higher cutaneous melanin reduces vitamin D3 production. This may impact lifetime vitamin D status and increase fracture risk. This study aimed to describe the relationship between spectrophotometrically determined constitutive melanin density, prevalent and incident fractures in a cohort of exclusively older Caucasian adults.

Methods

1072 community-dwelling adults aged 50–80 years had constitutive melanin density quantified using spectrophotometry. Participants were followed up at 2.5 (n = 879), 5 (n = 767), and 10 (n = 571) years after the baseline assessment. Prevalence and number of symptomatic fractures were assessed by questionnaire.

Results

Higher melanin density was independently associated with greater prevalence of any fracture (RR 1.08, p = 0.03), vertebral fracture (RR 1.41, p = 0.04) and major fracture (RR 1.12, p = 0.04) and the number of fractures (RR 1.09, p = 0.04) and vertebral fractures (RR 1.47, p = 0.04) in cross-sectional analysis. At the 2.5-year follow-up, higher melanin density was associated with incident fractures (RR 1.42, p = 0.01) and major fractures (RR 1.81, p = 0.01) and the number of incident fractures (RR 1.39, p = 0.02) and major fractures (RR 2.14, p = 0.01). The relationship between melanin density and incident fracture attenuated as the duration of follow-up increased and was not significant at the 5- or 10-year follow-up.

Conclusions

Constitutive melanin density was associated with prevalent and short-term, but not long-term, incident fracture risk in older Caucasian adults. This suggests melanin density either acts as a surrogate marker for an unmeasured fracture risk factor or the relationship between melanin density and fracture changes with time.

中文翻译：

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本构黑色素密度与高加索成年人的普遍和短期但不是长期的骨折风险有关。

概要

较高的皮肤黑色素会减少维生素D3的产生。这可能会增加骨折风险。我们发现，皮肤的黑色素密度与高加索成年人的普遍和短期而非长期的骨折风险有关。黑色素密度要么作为替代指标，要么与骨折随时间的变化有关。

介绍

较高的皮肤黑色素会减少维生素D3的产生。这可能会影响一生的维生素D状况并增加骨折风险。这项研究旨在描述分光光度法测定的本构年仅成年人的队列中黑色素密度，普遍性骨折和意外骨折之间的关系。

方法

使用分光光度法对1072位年龄在50-80岁之间的社区成年人进行了测定，其组成型黑色素密度得以定量。 在基线评估后的2.  5年（n = 879），5年（n  = 767）和10年（n = 571）对参与者进行了随访。通过问卷调查评估症状性骨折的发生率和数量。

结果

黑色素密度越高，与任何骨折（RR 1.08，p  = 0.03），椎骨骨折（RR 1.41，p  = 0.04）和大骨折（RR 1.12，p  = 0.04）和骨折数量（RR 1.09）的发生率越高，都独立相关。（p  = 0.04）和椎骨骨折（RR 1.47，p  = 0.04）。在2.5年的随访中，较高的黑色素密度与事件性骨折（RR 1.42，p  = 0.01）和主要骨折（RR 1.81，p  = 0.01）和事件性骨折数量（RR 1.39，p  = 0.02）相关。和主要骨折（RR 2.14 ，p = 0.01）。随着随访时间的延长，黑色素密度与事件性骨折之间的关系减弱，而在5年或10年的随访中并不显着。

结论

本构黑色素密度与高加索成年人的普遍和短期但不是长期的骨折风险有关。这表明黑色素密度或者是无法测量的骨折危险因素的替代标志，或者黑色素密度与骨折随时间的变化之间的关系。