Non-Significant Correlation of Vitamin D Deficiency and Five-Year Revisions Following Adult Spinal Deformity Surgery After Controlling for Osteoporosis: A National Database Analysis.

Adult spinal deformity (ASD) is a common condition, particularly prevalent among patients older than 65 years. 1 - 5 Corrective surgery may be considered for this patient population to improve quality of life by addressing the deformity, relieving pain, and mitigating neurological symptoms. 1 , 5 However, postoperative recovery is often challenging, with approximately one-third of patients experiencing complications, 6 and further surgery may be needed in the years that follow. 7 - 9

In recent years, hypovitaminosis D, or vitamin D deficiency, has emerged as a potential risk factor for adverse outcomes following spinal deformity surgery. It has been noted that a substantial percentage of patients undergoing elective spine surgery have vitamin D deficiency. 10 - 14 Vitamin D is crucial for bone formation, maintenance, and remodeling, as well as muscle function and musculoskeletal pain. 15 In addition, vitamin D plays an important role in wound healing, and among spine surgery patients, vitamin D deficiency may be associated with complications such as pseudarthrosis and impaired osseointegration of implanted device. 5

Current literature suggests that vitamin D deficiency is associated with poorer outcomes after spine surgery. 16 , 17 For example, a prospective study by Ravindra et al 10 found that vitamin D deficiency was linked to prolonged time to fusion and higher rates of nonunion following spinal fusion surgery. In addition, vitamin D deficiency has been associated with worse patient-reported disability and quality-of-life scores after elective spine procedures. 11 , 18 , 19 Based on these findings, some authors have recommended routine preoperative screening of vitamin D levels and supplementation as needed. 10 , 11 , 14 , 17

Osteoporosis is also common among adults undergoing spine surgery 20 , 21 and is an independent risk factor for adverse outcomes and revision surgery following ASD surgery. 6 , 8 , 22 - 26 Given the well-established relationship between vitamin D levels and bone mineral density, 27 - 29 a notable overlap is expected between ASD patients with vitamin D deficiency and those with osteoporosis. Thus, to accurately assess the independent correlation of vitamin D deficiency on spine surgery outcomes, it is likely important to control for osteoporosis status.

This study was performed to address the above-noted knowledge gap. Using a large, national database, this study aimed to clarify the interplay between vitamin D deficiency and osteoporosis as they relate to postoperative outcomes following ASD surgery.

Methods

Database and Cohort

A retrospective analysis was performed using the 2010 to Q1 2022 M161 PearlDiver Ortho Mariner Patient Claims Database (PearlDiver Technologies, Colorado Springs, CO). This commercially available database contains an extensive collection of over 161 million patient records in the United States. As data from this database are output in a deidentified and aggregated format, our institutional review board determined studies using this database to be exempt from review. With its vast repository of Health Insurance Portability and Accountability Act–compliant patient data, the PearlDiver database has gained increasing prominence in spine outcomes-based research. 30 - 39

International Classification of Diseases (ICD)-9 and ICD-10 codes were used to identify patients with a diagnosis of ASD (refer to Supplemental Table 1, http://links.lww.com/JG9/A461 ). Cases of spinal deformity surgery were queried using the Current Procedural Terminology codes 22206, 22207, 22212, 22214, 22800, 22802, and 22804. The following exclusion criteria were then applied: age <18 years, cases of infection or neoplasm, and missing 90-day follow-up health care data. In addition, patients with a diagnosis of connective tissue or rheumatologic disease, Paget disease of bone, multiple myeloma, hyperparathyroidism, cachexia, malabsorptive diseases such as inflammatory bowel disease or achalasia, or those who underwent previous bariatric surgery were excluded from the study. Patient age, sex, osteoporosis status, Charlson Comorbidity Index (CCI), insurance plan, and geographic region were extracted from the data set.

Vitamin D deficiency was then identified using ICD codes. Patients in the database were included in the vitamin D deficiency cohort if they had a recorded diagnosis of vitamin D deficiency between 730 days before spinal deformity surgery and up to 365 days after surgery. Using PearlDiver's exact match function, the non-vitamin D–deficient cohort and vitamin D–deficient cohort were matched 4:1 based on age, sex, and CCI. Subsequently, the index populations were rematched 4:1 based on age, sex, CCI, and osteoporosis status.

Postoperative Outcomes

Ninety-day incidence of adverse events was then abstracted from the database based on ICD coding for each matched cohort consistent with prior methodology. 34 , 37 - 39 The specific adverse events examined included serious adverse events (noted if there was the occurrence of deep vein thrombosis, pulmonary embolism, surgical site infection, sepsis, pancreatitis, or cardiac events [cardiac arrest or myocardial infarction]), minor adverse event (noted if there was the occurrence of wound dehiscence, urinary tract infection, hematoma, pneumonia, acute kidney injury, or transfusion). Any adverse event was noted if there was the occurrence of either a serious or minor adverse event.

Five-year rate of revision surgery was assessed for each matched cohort. Revision procedures were identified based on Current Procedural Terminology codes (see Supplemental Table 1, http://links.lww.com/JG9/A461 ).

Statistical Analysis

Variables such as patient demographics, comorbidities, and osteoporosis status were compared between patients in the non-vitamin D–deficient and vitamin D–deficient cohorts. Univariate analyses were performed using an independent two-tailed Student t -test for age and CCI, and Pearson chi squared test for sex, plan, and region. Univariate analyses of patient factors were subsequently conducted for the matched cohorts.

Multivariate logistic regression was used to ascertain odds ratios (ORs) and 95% confidence intervals (95% CIs) of 90-day adverse events, initially controlling for age, sex, and CCI. The analyses were subsequently repeated with the addition of osteoporosis as a matching and a controlling variable.

Kaplan-Meier survival analysis was performed to determine 5-year rates of revision surgery between the matched cohorts, censoring those lost to follow-up or deceased. Cumulative 5-year subsequent surgical rates, at any level, were compared with the log-rank test, once without matching for osteoporosis and once with matching.

Statistical analyses were performed using the PearlDiver platform's internal software, with an alpha value set at 0.05 for reoperations. Bonferroni correction with an alpha value set at 0.00417 was applied for multivariable ORs. Figures were created using Microsoft Excel (Microsoft Corporation) and GraphPad Prism 9 (GraphPad Software).

Results

Study Population

A total of 18,165 patients met the inclusion criteria for this study before matching: 17,517 (96.43%) in the non-vitamin D–deficient cohort and 648 (3.57%) in the vitamin D–deficient cohort. The characteristics of the unmatched cohort are summarized in Table 1 .

After matching for age, sex, and CCI, the study included 2,370 patients in the non-vitamin D–deficient group and 605 in the vitamin D–deficient group. The vitamin D–deficient cohort had a higher proportion of patients with osteoporosis compared with the non-vitamin D–deficient cohort, as detailed in Table 2 .

On matching for age, sex, CCI, and osteoporosis, there were 2,155 patients in the non-vitamin D–deficient cohort and 557 in the vitamin D–deficient cohort. These results are presented in Table 3 . A flow diagram outlining patient inclusion, exclusion, and matching is shown in Figure 1 .

Ninety-Day Outcomes

Ninety-day outcomes without matching for osteoporosis are described in Table 4 . Univariate analysis demonstrated significantly higher rates of aggregated any adverse events (33.88% vs. 26.62%, P < 0.001) and minor adverse events (27.27% vs. 20.34%, P < 0.001), as well as wound dehiscence ( P < 0.001) and urinary tract infection ( P = 0.002) in the vitamin D–deficient cohort compared with the non-vitamin D–deficient cohort.

Multivariate logistic regression, adjusting for differences in age, sex, and comorbidity profiles, was subsequently applied (Table 4 and Figure 2 ). Patient groups with 10 or fewer individuals were censored for confidentiality. Compared with the non-vitamin D–deficient cohort, vitamin D deficiency was associated with increased odds of aggregated adverse events (OR 1.34, P = 0.0033) and minor adverse events (OR 1.39, P = 0.0023). Specifically, wound dehiscence was the only isolated 90-day adverse event with increased odds in the vitamin D–deficient cohort (OR 1.91, P = 0.0015).

The analysis was repeated for cohorts matched for osteoporosis (Table 5 and Figure 3 ). Multivariate logistic regression, adjusting for age, sex, comorbidities, and osteoporosis, was performed on the matched cohort. The vitamin D–deficient group exhibited significantly higher odds of postoperative aggregated adverse events (OR 1.35, P = 0.0038) and urinary tract infection (OR 1.56, P = 0.0032). No significant differences were observed between the cohorts for other adverse events.

Five-Year Reoperations

For the cumulative incidence of reoperations within 5 years of the index procedure, the vitamin D–deficient cohort had a significantly higher 5-year revision surgery rate compared with the non-vitamin D–deficient cohort (39.3% vs. 31.7%, P = 0.006) when osteoporosis was not included as a matching variable (Figure 4 ).

However, when the cohorts were additionally matched for osteoporosis, Kaplan-Meier analysis showed no notable difference in 5-year revision surgery rates (Figure 5 ).

Discussion

This study evaluated 90-day and 5-year outcomes following ASD surgery in patients with and without a diagnosis of vitamin D deficiency. Overall, the 90-day perioperative adverse outcomes were similar between the cohorts regardless of whether osteoporosis was included as a matching/controlling variable. However, the greater 5-year revision rate associated with vitamin D deficiency became washed out when controlling for osteoporosis.

Vitamin D plays a fundamental role in bone remodeling by promoting the absorption of dietary calcium. A deficiency in vitamin D leads to increased parathyroid hormone release, which in turn results in decreased bone mineral density and, ultimately, osteoporosis. 40 Consequently, it is not surprising that a large proportion of patients undergoing spinal deformity surgery with vitamin D deficiency also have osteoporosis. This suggests that it is important to disentangle the independent effects of these conditions on surgical outcomes.

Several prior investigations have explored the relationship between vitamin D deficiency and spine surgery outcomes, but their results have been mixed. For instance, a prospective observational study by Ravindra et al. involving 133 patients found that vitamin D deficiency was associated with a markedly longer time to fusion and was an independent predictor of nonunion. 10 Similarly, Xu et al, 11 in a retrospective cohort study of 360 lumbar spine surgery patients, reported that vitamin D deficiency was linked to poorer patient outcome scores during the short-term recovery period. However, a retrospective chart review of 150 patients by Donnally et al 41 found no association between vitamin D levels and postoperative pseudarthrosis, revision surgery, or implant complications following lumbar spinal fusion. Importantly, none of these studies accounted for the confounding effect of osteoporosis, which is often concurrent with vitamin D deficiency. As a result, the lack of adjustment for osteoporosis may have influenced their conclusions.

In this study, we compared 90-day and 5-year outcomes following ASD surgery in patients with and without vitamin D deficiency and then assessed how the results changed when osteoporosis was included as a matching variable. Univariate analysis of the non–osteoporosis–matched cohorts revealed that the vitamin D deficiency group had a higher proportion of patients with osteoporosis, which is consistent with the known relationship between the two conditions. 27 - 29 , 42 The initial evaluation of 90-day outcomes demonstrated that vitamin D deficiency was associated with higher odds of experiencing aggregated adverse events, minor adverse events, and wound dehiscence. When osteoporosis was included as a matching/controlling variable, subsequent multivariate analysis revealed a similar higher rate of aggregate adverse events in the vitamin D–deficient cohort, with urinary tract infections showing increased odds in this group. These findings are supported by the known role Vitamin D plays in wound healing and immune defense mechanisms. 43 - 45 Nevertheless, in both instances, most isolated adverse events showed no notable difference between the two cohorts. These finding suggest overall similar in short term perioperative adverse events following ASD surgery in those with vitamin D deficiency compared with those without.

Analysis of 5-year cumulative survival to revision surgery revealed that the vitamin D–deficient cohort had a higher revision surgery rate at 5 years when osteoporosis was not accounted for. However, this difference washed away when the cohorts were additionally matched for osteoporosis, suggesting that the elevated revision surgery rate is more likely attributable to osteoporosis rather than vitamin D deficiency. These findings are consistent with existing literature that supports this notion. For instance, Gupta et al. reported that among 399 ASD surgery patients, a markedly higher proportion of those with osteoporosis required revision surgery compared with those without osteoporosis (40.5% vs. 28.0%). 25 In addition, a systematic review by Filley et al. identified osteoporosis as a notable risk factor for mechanical complications following lumbar fusion, 26 potentially contributing to increased rates of revision surgery.

This study has several limitations. Owing to the use of an administrative claims database, detailed clinical information regarding factors that may influence the effect of vitamin D deficiency—such as specific serum vitamin D levels, patient lifestyle factors such as sun exposure and dietary habits, and nuances in management decisions between the patient and surgeon—cannot be fully captured. In addition, administrative codes may lack the granularity needed to account for deformity and patient-specific pathologies that could influence outcomes. Moreover, the study is subject to inherent limitations of retrospective analyses using administrative databases, including the risk of selection bias and inaccuracies stemming from coding errors. 46 - 48

Conclusion

To our knowledge, this study is the largest to date to compare short-term adverse events and 5-year revision surgery rates in patients undergoing ASD surgery with and without vitamin D deficiency. Subgroup analyses adjusting for osteoporosis revealed similar short-term adverse event rates, regardless of whether osteoporosis was included as a matching/controlling variable. However, the difference in 5-year revision surgery rates disappeared when osteoporosis was included, suggesting that osteoporosis primarily drives this association. These findings underscore the importance of accounting for osteoporosis when evaluating surgical outcomes in patients with concurrent vitamin D deficiency.

Supplementary Material

SUPPLEMENTARY MATERIAL

Footnotes

Mr. Jayaram: Received funding from the National Institute on Aging of the National Institutes of Health. The research content is the authors' responsibility and does not represent the official views of the National Institutes of Health under Award Number T35AG049685.

Dr. Bouloussa or an immediate family member has Shareholder for DeBogy molecular. Dr. Grauer or an immediate family member is a member of a speakers' bureau or has made paid presentations on behalf of North American Spine Society Past Board Member; North American Spine Society Journal Editor-in-chief; Journal of the American Academy of Orthopaedic Surgeons Deputy Editor. None of the following authors or any immediate family member has received anything of value from or has stock or stock options held in a commercial company or institution related directly or indirectly to the subject of this article: Mr. Jayaram, Mr. Jonnalagadda, Dr. Surucu, and Ms. Maloy.

Our institutional review board (IRB) found studies utilizing the current dataset to be exempt from review.

Contributor Information

Rahul H. Jayaram, Email: rahul.jayaram@yale.edu.

Serkan Surucu, Email: serkansurucu@outlook.com.

Anshu Jonnalagadda, Email: anshu.jonnalagadda@yale.edu.

Gwyneth C. Maloy, Email: gwyneth.maloy@yale.edu.

Houssam Bouloussa, Email: houssam.bouloussa@uhkc.org.

References

1. Diebo BG, Shah NV, Boachie-Adjei O, et al. : Adult spinal deformity. Lancet 2019;394:160-172.

2. Acaroğlu RE, Dede Ö, Pellisé F, et al. : Adult spinal deformity: A very heterogeneous population of patients with different needs. Acta Orthop Traumatol Turc 2016;50:57-62.

3. Kim HJ, Yang JH, Chang DG, et al. : Adult spinal deformity: Current concepts and decision-making strategies for management. Asian Spine J 2020;14:886-897.

4. Berreta RS, Zhang H, Alsoof D, et al. : Adult spinal deformity correction in patients with parkinson disease: Assessment of surgical complications, reoperation, and cost. World Neurosurg 2023;178:e331-e338.

5. Ames CP, Scheer JK, Lafage V, et al. : Adult spinal deformity: Epidemiology, health impact, evaluation, and management. Spine Deform 2016;4:310-322.

6. Akıntürk N, Zileli M, Yaman O: Complications of adult spinal deformity surgery: A literature review. J Craniovertebr Junction Spine 2022;13:17-26.

7. Kelly MP, Lenke LG, Bridwell KH, Agarwal R, Godzik J, Koester L: Fate of the adult revision spinal deformity patient: A single institution experience. Spine (Phila Pa 1976) 2013;38:E1196-E1200.

8. Puvanesarajah V, Shen FH, Cancienne JM, et al. : Risk factors for revision surgery following primary adult spinal deformity surgery in patients 65 years and older. J Neurosurg Spine 2016;25:486-493.

9. Pichelmann MA, Lenke LG, Bridwell KH, Good CR, O'Leary PT, Sides BA: Revision rates following primary adult spinal deformity surgery: Six hundred forty-three consecutive patients followed-up to twenty-two years postoperative. Spine (Phila Pa 1976) 2010;35:219-226.

10. Ravindra VM, Godzik J, Dailey AT, et al. : Vitamin D levels and 1-Year fusion outcomes in elective spine surgery: A prospective observational study. Spine (Phila Pa 1976) 2015;40:1536-1541.

11. Xu HW, Shen B, Hu T, Zhao WD, Wu DS, Wang SJ: Preoperative vitamin D status and its effects on short-term clinical outcomes in lumbar spine surgery. J Orthop Sci 2020;25:787-792.

12. Stoker GE, Buchowski JM, Bridwell KH, Lenke LG, Riew KD, Zebala LP: Preoperative vitamin D status of adults undergoing surgical spinal fusion. Spine (Phila Pa 1976) 2013;38:507-515.

13. Zolfaghari F, Faridmoayer A, Soleymani B, Taji M, Mahabadi M: A survey of vitamin D status in patients with degenerative diseases of the spine. Asian Spine J 2016;10:834-842.

14. Lindley EM, Perry J, Patel M, et al. : Vitamin D hypovitaminosis and efficacy of supplementation in spine surgery patients. Curr Orthopaedic Pract 2019;30:250-253.

15. Rodriguez WJ, Gromelski J: Vitamin d status and spine surgery outcomes. ISRN Orthop 2013;2013:471695.

16. Mayo BC, Massel DH, Yacob A, et al. : A review of vitamin D in spinal surgery: Deficiency screening, treatment, and outcomes. Int J Spine Surg 2020;14:447-454.

17. Kerezoudis P, Rinaldo L, Drazin D, et al. : Association between vitamin D deficiency and outcomes following spinal fusion surgery: A systematic review. World Neurosurg 2016;95:71-76.

18. Kim TH, Yoon JY, Lee BH, et al. : Changes in vitamin D status after surgery in female patients with lumbar spinal stenosis and its clinical significance. Spine (Phila Pa 1976) 2012;37:E1326-E1330.

19. Khalooeifard R, Rahmani J, Tavanaei R, et al. : The effect of vitamin D deficiency on outcomes of patients undergoing elective spinal fusion surgery: A systematic review and meta-analysis. Int J Spine Surg 2022;16:53-60.

20. Gupta A, Cha T, Schwab J, et al. : Osteoporosis is under recognized and undertreated in adult spinal deformity patients. J Spine Surg 2021;7:1-7.

21. Chin DK, Park JY, Yoon YS, et al. : Prevalence of osteoporosis in patients requiring spine surgery: Incidence and significance of osteoporosis in spine disease. Osteoporos Int 2007;18:1219-1224.

22. Varshneya K, Bhattacharjya A, Jokhai RT, et al. : The impact of osteoporosis on adult deformity surgery outcomes in medicare patients. Eur Spine J 2022;31:88-94.

23. Lechtholz-Zey EA, Gettleman BS, Ayad M, et al. : The effect of osteoporosis on complications and reoperation rates after surgical management of adult thoracolumbar spinal deformity: A systematic review and meta analysis. Glob Spine J 2024;14:2420-2439.

24. Baroudi M Daher M Maheshwari K, et al. Surgical management of adult spinal deformity patients with osteoporosis. J Clin Med. 2024;13:7173.

25. Gupta A, Cha T, Schwab J, et al. : Osteoporosis increases the likelihood of revision surgery following a long spinal fusion for adult spinal deformity. Spine J 2021;21:134-140.

26. Filley A, Baldwin A, Ben-Natan AR, et al. : The influence of osteoporosis on mechanical complications in lumbar fusion surgery: A systematic review. N Am Spine Soc J 2024;18:100327.

27. Metzger MF, Kanim LE, Zhao L, Robinson ST, Delamarter RB: The relationship between serum vitamin D levels and spinal fusion success: A quantitative analysis. Spine (Phila Pa 1976) 2015;40:E458-E468.

28. Lips P, Hosking D, Lippuner K, et al. : The prevalence of vitamin D inadequacy amongst women with osteoporosis: An international epidemiological investigation. J Intern Med 2006;260:245-254.

29. Sadat-Ali M, Al Elq AH, Al-Turki HA, Al-Mulhim FA, Al-Ali AK: Influence of vitamin D levels on bone mineral density and osteoporosis. Ann Saudi Med 2011;31:602-608.

30. Gouzoulis MJ, Seddio AE, Rancu A, et al. : Trends in management of odontoid fractures 2010-2021. N Am Spine Soc J 2024;20:100553.

31. Gouzoulis MJ, Jabbouri SS, Seddio AE, et al. : Rate and risk factors for inpatient falls following single-level posterior lumbar fusion: A national registry study. N Am Spine Soc J 2024;20:100549.

32. Jayaram RH, Oghenesume OP, Day W, Kammien AJ, Grauer JN: Emergency department use within 90 days after single-level posterior cervical foraminotomy. Orthopedics 2025;48:51-56.

33. Dhodapkar MM, Halperin SJ, Seddio AE, Dahodwala T, Rubio DR, Grauer JN: Utilization and timing of surgical intervention for central cord syndrome in the United States. Eur Spine J 2024;33:3645-3651.

34. Gouzoulis MJ, Seddio AE, Winter AD, et al. : Robotic-assisted versus navigation-assisted posterior lumbar fusion: A national database study. Spine (Phila Pa 1976) 2024;49:1483-1487.

35. Kim LY, Halperin SJ, Grauer JN: Surgical site infection following isolated lumbar discectomy increases odds of revision lumbar surgery within first 6 months, but not beyond. Spine J 2024;24:1459-1466.

36. Kim L, Grauer JN: Anterior cervical decompression and fusion at one and two levels: Trends and factors associated with structural allograft versus synthetic cages. N Am Spine Soc J 2024;17:100310.

37. Kammien AJ, Zhu JR, Gillinov SM, Gouzoulis MJ, Grauer JN: Adverse events after posterior lumbar fusion are not sufficiently characterized with 30-day follow-up: A database study. J Am Acad Orthop Surg 2022;30:528-533.

38. Seddio AE, Katsnelson BM, Smith-Voudouris J, et al. : Inflammatory bowel disease is associated with greater odds of complications following posterior lumbar fusion and further amplified for patients exposed to monoclonal antibody biologics. N Am Spine Soc J 2024;20:100574.

39. Seddio AE, Gouzoulis MJ, Vasudevan RS, et al. : Semaglutide utilization associated with reduced 90-day postoperative complications following single-level posterior lumbar fusion for patients with type II diabetes. Spine J 2025;25:485-493.

40. Bhattarai HK, Shrestha S, Rokka K, Shakya R: Vitamin D, calcium, parathyroid hormone, and sex steroids in bone health and effects of aging. J Osteoporos 2020;2020:9324505.

41. Donnally CJ, III, Sheu JI, Bondar KJ, et al. : Is there a correlation between preoperative or postoperative vitamin D levels with pseudarthrosis, hardware failure, and revisions after lumbar spine fusion? World Neurosurg 2019;130:e431-e437.

42. De Martinis M, Allegra A, Sirufo MM, et al. : Vitamin D deficiency, osteoporosis and effect on autoimmune diseases and hematopoiesis: A review. Int J Mol Sci 2021;22:8855.

43. Siregar FD, Hidayat W: The role of vitamin D on the wound healing process: A case series. Int Med Case Rep J 2023;16:227-232.

44. Smith K, Hewlings S: Correlation between vitamin D levels and hard-to-heal wounds: A systematic review. J Wound Care 2020;29:S24-S30.

45. Gombart AF: The vitamin D-antimicrobial peptide pathway and its role in protection against infection. Future Microbiol 2009;4:1151-1165.

46. Rancu AL, Gouzoulis MJ, Winter AD, Katsnelson BM, Ansah-Twum JK, Grauer JN: Opioid prescribing trends following lumbar discectomy. J Am Acad Orthop Surg 2024;33:1054-1059.

47. Kammien AJ, Galivanche AR, Gouzoulis MJ, Moore HG, Mercier MR, Grauer JN: Emergency department visits within 90 days of single-level anterior cervical discectomy and fusion. N Am Spine Soc J 2022;10:100122.

48. Sabatino MJ, Burroughs PJ, Moore HG, Grauer JN: Spine coding transition from ICD-9 to ICD-10: Not taking advantage of the specificity of a more granular system. N Am Spine Soc J 2020;4:100035.

Associated Data

Supplementary Materials

SUPPLEMENTARY MATERIAL