Effects of overnight fasting on handgrip strength in inpatients

ABSTRACT Objective: To investigate the effects of overnight fasting on handgrip strength of adult inpatients. Methods: A prospective clinical study enrolling 221 adult patients. The endpoints were handgrip strength obtained by dynamometry in three time points (morning after an overnight fasting, after breakfast and after lunch) and the cumulative handgrip strength (mean of handgrip strength after breakfast and lunch) in the same day. The mean of three handgrip strength measures was considered to represent each time point. A cut-off for the mean overnight fasting handgrip strength at the 50th percentile (35.5kg for males and 27.7kg for females) was used for comparisons. We registered the age, sex, current and usual weight (kg), weight loss (kg), diagnosis of cancer, nutritional status, elderly frequency, digestive tract symptoms, type of oral diet, and the amount of dinner ingested the night before handgrip strength (zero intake, until 50%, <100% and 100%). Results: Handgrip strength evaluated after an overnight fasting (31.2±8.7kg) was lesser when compared with handgrip strength after breakfast (31.6±8.8kg; p=0.01), and with cumulative handgrip strength (31.7±8.8kg; p<0.001). Handgrip strength was greater in patients who ingested 100% (33.2±9.1kg versus 30.4±8.4kg; p=0.03) and above 50% of dinner (32.1±8.4kg versus 28.6±8.8kg; p=0.006). Multivariate analysis showed that ingesting below 50% of dinner, severe malnutrition, and elderly were independent factors for handgrip strength reduction after overnight fasting. Conclusion: The muscular function was impaired after an overnight fasting of adult patients hospitalized for medical treatment, especially for those with low ingestion, malnourished and elderly.

摘要
研究目的：探讨隔夜禁食对成年住院患者握力的影响。
研究方法：本研究为一项纳入221名成年患者的前瞻性临床研究。本研究的结局指标为同日三个时间点（隔夜禁食后晨起、早餐后及午餐后）通过握力计测定的握力，以及累积握力（早餐后与午餐后握力的平均值）；以三次握力测量的平均值作为各时间点的握力代表值。以隔夜禁食后平均握力的第50百分位数（男性35.5kg、女性27.7kg）作为截断值（cut-off）进行组间比较。本研究收集的资料包括：年龄、性别、当前体重与既往体重（单位：kg）、体重下降量（单位：kg）、癌症诊断史、营养状况、高龄状态、消化道症状、口服饮食类型，以及握力测量前一晚的晚餐摄入量（零摄入、≤50%、<100%及100%）。
研究结果：隔夜禁食后测定的握力为（31.2±8.7）kg，低于早餐后的握力（31.6±8.8）kg，差异具有统计学意义（p=0.01），同时也低于累积握力（31.7±8.8）kg，差异具有显著统计学意义（p<0.001）。晚餐摄入量为100%的患者握力为（33.2±9.1）kg，高于摄入量<100%患者的（30.4±8.4）kg，差异具有统计学意义（p=0.03）；晚餐摄入量>50%的患者握力为（32.1±8.4）kg，高于摄入量≤50%患者的（28.6±8.8）kg，差异具有显著统计学意义（p=0.006）。多因素分析结果显示，晚餐摄入量<50%、重度营养不良及高龄是成年住院患者隔夜禁食后握力下降的独立危险因素。
研究结论：成年住院患者隔夜禁食后肌肉功能受损，尤以晚餐摄入不足、营养不良及高龄患者为甚。