Prevalence and associated risk factors for hypovitaminosis D in patients scheduled for primary total hip arthroplasty in Germany.

BACKGROUND

Hypovitaminosis D is widespread in orthopaedic patients and may influence outcomes following joint arthroplasty. However, data specifically addressing vitamin D status in patients undergoing primary total hip arthroplasty (THA) remain limited. This study aimed to determine the prevalence of hypovitaminosis D and identify associated risk factors in a large German THA cohort.

METHODS

In this prospective single-centre study, 679 consecutive patients scheduled for primary THA due to osteoarthritis were evaluated over a 12-month period. Preoperative serum 25-hydroxyvitamin D (25[OH]D), parathyroid hormone, and calcium levels were measured. Vitamin D status was categorised as deficiency (⩽19 ng/mL), insufficiency (20-29 ng/mL), or sufficiency (⩾30 ng/mL). Associations between vitamin D status and demographic, clinical, and seasonal variables were analysed using χ2 tests, ANOVA, and multivariable linear and logistic regression models.

RESULTS

The mean serum 25(OH)D level was 26.0 ± 13.2 ng/mL, and hypovitaminosis D was present in 66,3% of patients (33.9% deficiency, 32.4% insufficiency). Season of sampling showed no significant influence on vitamin D levels. In multivariable analysis, preoperative vitamin D supplementation was the strongest positive predictor of higher 25(OH)D levels (B = +16.1 ng/mL; p < 0.001), while higher BMI category (B = -1.64 ng/mL per category; p < 0.001) and male sex (B = -2.45 ng/mL; p = 0.010) were independently associated with lower levels. Logistic regression confirmed reduced odds of vitamin D sufficiency among men (OR 0.59; p = 0.007) and with increasing BMI category (OR 0.74; p = 0.002). Vitamin D status was not associated with smoking, comorbidity burden, season, or functional scores (WOMAC, EuroQol).

CONCLUSIONS

Hypovitaminosis D is highly prevalent in German patients undergoing primary THA, independent of season. Obesity and male sex are significant risk factors, whereas supplementation is strongly protective. Routine preoperative assessment and targeted optimisation of vitamin D levels, particularly in high-risk subgroups, may represent a simple, cost-effective component of arthroplasty prehabilitation. Further research is needed to determine whether correcting vitamin D deficiency translates to improved postoperative outcomes.