Images in clinical medicine. Osteomalacia

The handgrip strength threshold of 16 kg discriminates successful rehabilitation: A prospective short-term study of 258 women with hip fracture

AIM

In 2019 the European Working Group on Sarcopenia in Older People (EWGSOP) indicated weakness as the key characteristic of sarcopenia and released the threshold of 16 kg for handgrip strength to define weakness in women. We aimed to externally validate the 16 kg cut-off point for predicting functional recovery in 258 women with subacute hip fracture admitted to our rehabilitation ward.

METHODS

We assessed handgrip strength by a hand-grip Jamar dynamometer at admission to inpatient rehabilitation and functional ability in activities of daily living by the Barthel index at the end of the rehabilitation course. Successful rehabilitation was defined with a Barthel index score ≥85 and highest possible recovery with a Barthel index effectiveness = 100 %.

RESULTS

A handgrip strength ≥16 kg significantly predicted both successful rehabilitation (χ2 = 23.5, P < 0.001) and highest possible recovery (χ2 = 31.05, P < 0.001). For the women with a handgrip strength ≥16 kg, the odds ratios to gain successful rehabilitation and highest possible recovery were 2.68 (95 % CI from 1.19 to 6.04; P = 0.018) and 2.81 (95 % CI from 1.47 to 5.37; P = 0.002), after adjustment for Barthel index scores before rehabilitation, age, hip-fracture type (either medial or lateral), cognitive impairment and 25-hydroxyvitamin D levels.

CONCLUSION

Our results provide an external validation of the 16 kg handgrip strength threshold recently released to discriminate functional outcomes: it significantly predicted the short-term ability to perform activities of daily living after hip fracture in women.

Classes of vitamin D status and functional outcome after hip fracture: a prospective, short-term study of 1350 inpatients

BACKGROUND

Vitamin D depletion is associated with unfavourable outcomes after hip fracture. However, the classes of vitamin D status currently in use, which are defined according to serum calcifediol levels, have not been validated for their predictive capability of the functional recovery.

AIM

To investigate the association between serum calcifediol categorized into 4 classes and the functional recovery after hip fracture.

DESIGN

Prospective, short-term observational study.

SETTING

Rehabilitation hospital in Italy.

POPULATION

We evaluated 1350 of 1412 inpatients with hip fracture.

METHODS

Serum calcifediol was measured by an immunoenzymatic assay 14.7±4.4 (mean±SD) days after surgery and categorized into 4 classes: I class <12 ng/mL; II class 12-20 ng/mL; III class 21-29 ng/mL; IV class ≥30ng/mL. The functional outcome was assessed by using the Barthel Index.

RESULTS

We found a significant difference in Barthel index scores at the end of inpatient rehabilitation across the 4 classes of vitamin D status: χ2 (3, N.=1350) 27.2; P<0.001. The difference persisted after adjustment for 8 covariates (P=0.004). By comparing pairs of classes, we found that Barthel index scores were lower in the 829 patients of the I class than in the 275 of the II (P=0.005) who had in turn Barthel index scores lower than the 132 patients of the III class (P=0.038). Conversely, no significant differences emerged between the patients of the III class and the 114 patients of the IV class (P=0.421). The results did not materially change when Barthel Index effectiveness was substituted for Barthel Index scores as the outcome measure.

CONCLUSIONS

Calcifediol levels below 12ng/mL were associated with a worse recovery than those between 12 and 20ng/mL that were in turn associated with a worse recovery than those between 21 and 29 ng/mL. Conversely, no significant differences were found between the patients with calcifediol between 21 and 29ng/mL and those with calcifediol ≥30 ng/mL.

CLINICAL REHABILITATION IMPACT

Despite caution due to the observational design, our study suggests that vitamin D depletion should be treated after hip fracture to optimize the functional outcome, with a target level for serum calcifediol of 21-29ng/mL and no further advantages associated with calcifediol levels of 30ng/mL or higher.