\documentclass[10pt]{article}

\usepackage{fullpage}
\usepackage{setspace}
\usepackage{parskip}
\usepackage{titlesec}
\usepackage[section]{placeins}
\usepackage{xcolor}
\usepackage{breakcites}
\usepackage{lineno}
\usepackage{hyphenat}





\PassOptionsToPackage{hyphens}{url}
\usepackage[colorlinks = true,
            linkcolor = blue,
            urlcolor  = blue,
            citecolor = blue,
            anchorcolor = blue]{hyperref}
\usepackage{etoolbox}
\makeatletter
\patchcmd\@combinedblfloats{\box\@outputbox}{\unvbox\@outputbox}{}{%
  \errmessage{\noexpand\@combinedblfloats could not be patched}%
}%
\makeatother


\usepackage{natbib}




\renewenvironment{abstract}
  {{\bfseries\noindent{\abstractname}\par\nobreak}\footnotesize}
  {\bigskip}

\titlespacing{\section}{0pt}{*3}{*1}
\titlespacing{\subsection}{0pt}{*2}{*0.5}
\titlespacing{\subsubsection}{0pt}{*1.5}{0pt}


\usepackage{authblk}


\usepackage{graphicx}
\usepackage[space]{grffile}
\usepackage{latexsym}
\usepackage{textcomp}
\usepackage{longtable}
\usepackage{tabulary}
\usepackage{booktabs,array,multirow}
\usepackage{amsfonts,amsmath,amssymb}
\providecommand\citet{\cite}
\providecommand\citep{\cite}
\providecommand\citealt{\cite}
% You can conditionalize code for latexml or normal latex using this.
\newif\iflatexml\latexmlfalse
\providecommand{\tightlist}{\setlength{\itemsep}{0pt}\setlength{\parskip}{0pt}}%

\AtBeginDocument{\DeclareGraphicsExtensions{.pdf,.PDF,.eps,.EPS,.png,.PNG,.tif,.TIF,.jpg,.JPG,.jpeg,.JPEG}}

\usepackage[utf8]{inputenc}
\usepackage[ngerman,english]{babel}



\usepackage{float}








\begin{document}

\title{Multiple vertebral fractures after suspension of denosumab. A series of
56 cases.}



\author[1]{Manuel Sosa-Henríquez}%
\author[2]{Oscar Torregrosa}%
\author[3]{Alejandro Déniz}%
\author[1]{Pedro Saavedra}%
\author[4]{Norberto Ortego}%
\author[5]{Ana Turrión}%
\author[6]{José Luis Pérz Castrillón}%
\author[7]{Manuel Díaz-Curiel}%
\author[8]{Carlos Gómez-Alonso}%
\author[9]{Guillermo Martínez}%
\author[10]{José Antonio Blázquez}%
\author[11]{José Manuel Olmos-Martínez}%
\author[12]{Íñigo Etxebarria}%
\author[13]{José Ramón Caeiro}%
\author[14]{Damián Mora-Peña}%
\affil[1]{University of Las Palmas de Gran Canaria}%
\affil[2]{Hospital General Universitario de Elche}%
\affil[3]{Hospital Universitario Insular de Gran Canaria}%
\affil[4]{Hospital Universitario San Cecilio}%
\affil[5]{Hospital Universitario de Salamanca}%
\affil[6]{Hospital Universitario Río Hortega}%
\affil[7]{Hospital Universitario Fundación Jiménez Díaz}%
\affil[8]{Hospital Universitario Central de Asturias}%
\affil[9]{Hospital Universitario 12 de Octubre}%
\affil[10]{Hospital General Universitario de Albacete}%
\affil[11]{Hospital Universitario Marqués de Valdecilla Servicio de Medicina Interna}%
\affil[12]{Hospital Alto Deba}%
\affil[13]{University Hospital of Santiago de Compostela}%
\affil[14]{Hospital Virgen de la Luz}%


\vspace{-1em}



  
  \date{May 23, 2024}


\begingroup
\let\center\flushleft
\let\endcenter\endflushleft
\maketitle
\endgroup





\selectlanguage{english}
\begin{abstract}
Background: Denosumab is a monoclonal antibody approved for the
treat-ment of postmenopausal osteoporosis. The withdrawal of denosumab
produc-es an abrupt loss of bone mineral density and may cause multiple
vertebral fractures (MVF). Objective: To study the clinical, biochemical
and densitometric characteristics in a large series of postmenopausal
women who suffered MVF after deno-sumab withdrawal. Likewise, we try to
identify those factors related to the presence of a greater number of
vertebral fractures (VF). Patients and Methods: 56 patients (54 women)
who suffered MVF after re-ceiving denosumab at least for 3 consecutive
years and abruptly suspended it. A clinical examination was carried out.
Biochemical bone remodeling markers (BBRM) and bone densitometry at the
lumbar spine and proximal femur were measured. VF were diagnosed by MRI,
X-ray or both at dorsal and lumbar spine. Results: 56 patients presented
a total of 192 VF. 41 patients (73.2\%) had not previously suffered VF.
After discontinuation of the drug, a statistically signifi-cant increase
in the BBRM was observed. In the multivariate analysis, only the time
that denosumab was previously received was associated with the pres-ence
of a greater number of VF (p = 0.04). Conclusions: We present the series
with the largest number of patients col-lected to date. 56 patients
accumulated 192 new VF. After the suspension of denosumab and the
production of MVF, an increase in the serum values of the BBRM. The time
of denosumab use was the only parameter associated with a greater number
of fractures.%
\end{abstract}%



\sloppy


\textbf{Introduction}

Denosumab (DMAB), a monoclonal antibody against the receptor activator
of nuclear factor k-B ligand (RANKL), is a potent antiresorptive agent
commonly prescribed in patients with postmenopausal osteoporosis. DMAB
reduces bone resorption and improves bone mineral density (BMD) (1).The
FREEDOM trial found reduced risk of fragility fracture, a study that
lasted 10 years (2,3)

Unlike bisphosphonates, which have a residual effect on bone when
deposited therein (4), discontinuing DMAB treatment may produce a
rebound effect on markers of bone remodeling and a loss of bone mass to
the extreme that their values are even below the existing values before
starting treatment (5). Furthermore, since 2015, several case reports
and series were published describing multiple vertebral fractures (MVF)
in patients discontinuing DMAB, which are also characterized by being
painful. (6--9). Recently, 3 cases have been described of patients who
suffered a hip fracture after the suspension of denosumab (10) and also
repeated fractures in the same patient (11). The mechanism by which this
complication occurs is unknown, as is its exact incidence (11).

Most of the articles published to date describe isolated cases or series
with few patients. In this study, we present a series of 56 patients who
suffered multiple vertebral fractures after discontinuing DMAB as well
as a study of their clinical, analytical and densitometric
characteristics. This series includes the largest number of patients
published so far, with the aim of identifying prognostic factors for
higher risk patients and establish the most appropriate preventive
actions.

\textbf{Patients and Methods.}

The study was carried out in Spain, between April 1, 2019 and January
31, 2020, coordinated by the working group on osteoporosis and mineral
metabolism of the Spanish Society of Internal Medicine (SEMI). Patients
who had previously received a minimum of one year of DMAB treatment,
injecting at least 2 doses, having produced a minimum delay of 2 months
from the moment of injection, were included. Patients must have suffered
at least one fragility fracture after discontinuation of DMAB. This
fracture was verified by a lateral radiography of the thoracic and
lumbar spine, an MRI of the entire spine, or both. Genant's
classification (12) was applied to diagnose vertebral fracture. Those
patients with cancer, Paget's disease of bone or when the fracture was
traumatic were excluded. The collection of clinical data was carried out
with a questionnaire designed for this purpose.

\emph{Bone densitometry:}

All patients had at least two dual X-ray absorptiometry (DXA) exams: one
before or at the time of DMAB initiation and one after VF occurrence.
Exams were carried out with different machines for different patients,
but the same for each patient, allowing us to compare both exams.
T-scores were calculated using normal values for the Spanish population.
For biochemical determinations, fasting blood was drawn. The biochemical
parameters: creatinine, total proteins, calcium and phosphorus were
measured using standardized colorimetric methods.
Immunochemiluminescence was used to determine the biochemical parameters
of bone remodeling: P1NP, beta-crosslaps and osteocalcin.

\textbf{} \selectlanguage{english}VF diagnosis was confirmed by MRI assessed by a radiologist,
except in four patients in which it was based on shape changes in X-ray
exams as compared to recent previous images.

The study was carried out following the rules of the Declaration of
Helsinki (13), the protocol approved by the Insular University Hospital
of Gran Canaria Clinical Trials Committee. All patients were informed of
the study objectives and gave their informed written consent.

\textbf{Statistical analysis} \emph{Univariate analysis.} Categorical
variables are expressed as frequencies and percentages and continuous as
mean and standard deviation (SD). Paired means were compared using the
Wilcoxon test for paired data.\emph{Poisson models.} The effect of each
factor (\emph{X} ) on the number of vertebral fractures after DMAB
(\emph{nVF} ) was analyzed by means of the Poisson model:
\(\text{nVFPoisson}\left(\mu\right)\), being:

\begin{equation}
\log\left(\mu\right)=\alpha+\beta X\nonumber \\
 \end{equation}

Where \(\mu\) is the expected number of vertebral fractures,
which may depend on the \emph{X} factor. When \(X\) is a
binary variable indicating presence or absence of a character its values
were coded as 1 (presence) and 0 (absence). From this model it follows:

\begin{equation}
\frac{\mu\left(X=t+1\right)}{\mu\left(X=t\right)}=exp\left(\beta\right)\nonumber \\
 \end{equation}

Where \(\mu\left(X=t\right)\) corresponds to the expected number of vertebral
fractures when the factor \emph{X} is in level \emph{t} . Therefore,
\(\exp\left(\beta\right)\) correspond to the proportion of variation of the
expected number of vertebral fractures for each unit that varies
\emph{X.}

Statistical significance was set at p \textless{} 0.05. Data were
analyzed using the R package, version 3.6.1 (R Development Core Team,
2019).

\textbf{Results}

Table 1 shows the baseline characteristics of our study patients. A
total of 56 patients were included, of which 54 were women (96.4\%). The
mean age was 68.1 \selectlanguage{ngerman}± 8.2 years. The most frequently observed concomitant
diseases were arterial hypertension (32.1\%), dyslipidemia (32.1\%) and
hypothyroidism (16.1\%). Most of the patients had not previously
suffered vertebral fractures (73.2\%) and their risk of fracture
calculated at 10 years using the FRAX risk assessment tool after having
suffered multiple vertebral fractures was 11\% for major fractures (95\%
CI 6.1\% -16\%) and 3.9\% for hip fractures (1.2\% -6.6\%). Patients had
been taking DMAB for a median of 30.5 months (95\% CI: 24-43.5 months)
and had injected a median of 6 doses (95\% CI: 4-8 doses). 56 patients
accumulated 192 new vertebral fractures.

Table 3 shows the reasons why DMAB was discontinued. Medical
prescription was the main cause of suspending treatment, which occurred
in 62.7\% of cases.

Table 4 shows the biochemical values studied, including the biochemical
markers of bone remodeling, obtained before and after DMAB suspension
and the appearance of multiple vertebral fractures. Values of calcium,
phosphorus, total proteins, vitamin D (25 hydroxycholecalciferol) and
PTH do not change substantially, but the biochemical markers of bone
remodeling increase significantly, both beta-crosslaps, P1NP and
osteocalcin (p \textless{}0.006 in all cases). The greatest increase
occurs in the beta-crosslaps, from 0.071 to 0.520 ng/mL median, a
14-fold increase in baseline values. Osteocalcin values almost tripled
while those of P1NP quadrupled.

Finally, Table 5 shows the logistic regression analysis to study the
possible association between the various clinical, analytical and
densitometric parameters and the number of vertebral fractures. The
length of time of previous DMAB use is the only parameter that was
associated in a statistically significant way (p= 0.04).

\textbf{Discussion}

Our study included a total of 56 patients and constitutes the largest
number of cases collected in a single series. Previous studies presented
a smaller number of cases. González-Rodríguez et al (7) collected 60
spontaneous vertebral fractures in 15 women with breast cancer who were
undergoing treatment with aromatase inhibitors and in whom denosumab was
discontinued. Fernández Fernández et al (14) described 49 vertebral
fractures in 10 women and Florez et al (15) published a series of 7
women who had a median of 5 vertebral fractures. Another study collected
the first 3 cases of hip fracture produced after abrupt DMAB
discontinuation in the absence of other causes (10). Several systematic
reviews have confirmed the magnitude of the problem (6,16-18). In this
series, we publish the first two cases described in men.

The actual number of cases is probably much higher. The Spanish Agency
for Medicines and Health Products (AEMPS), which collects adverse
effects of drugs, described in 2019 a total of 64 patients with multiple
vertebral fractures that were increased in a subsequent statement in
2020, 213 patients with multiple vertebral fractures and 50 hip
fractures. There are several reasons that might explain why the
magnitude of the problem is not preceived. We would mention: a) it is a
complication not yet sufficiently known by the medical community in
general, b) they are fractures that occur in patients who have
osteoporosis, therefore, they can be attributed to the disease rather
than to the suspension of the drug, c) given that the drug is
administered every 6 months, it is possible to forget it, especially
when the questioning is directed at drugs that are taken orally, and d)
for scientific journals, the publication of new cases do not provide
anything noteworthy. So, in recent years, the number of publications on
the matter has decreased, while the number of fractures has not.

The mean age of our series was 68.1 years, somewhat older than those
described in other series, such as that of Barcelona, where the median
age was 65 years (15), and that of Madrid with a mean of 66.4 years (14
). In the González-Rodríguez series (7), the mean age was lower, 62.3
years, but they were other types of patients, women with breast cancer
and not postmenopausal osteoporosis. In a systematic review in which 24
cases were collected, the mean age was 64.1 years (6).

Our patients had received a median of 6 doses, with DMAB having been
used a median of 30.5 months. These results coincide with those
published in other series and reports of individual cases
(6--8,10,14--16,19--23). In a ``real world'' study, the risk of fracture
when discontinuing DMAB treatment has been calculated to increase
markedly when the third injection is given (16). The time it takes for
fractures to occur after the last dose of DMAB showed a median of 11
months in our study, which represents a 5-month delay, since the drug is
administered every six months, although in one case it occurred after
the delay of a month and a half. In different reported cases, this
period ranges from 2 to 13 months (6,8,14,15).

Probably the appearance of fractures will depend on two factors, the
severity of the disease and the withdrawal of the drug. The severity of
the disease could be determined through the FRAX or by the presence of
previous fractures. The 10-year risk of fracture calculated by the FRAX
tool showed a median of 11\% for major fracture and 3.9\% for hip
fracture. Although there is a debate on the optimal threshold to perform
a therapeutic intervention (24--26), the high risk of fracture has been
established at 20\% for the major fracture and 3\% for the hip fracture
(27). In our study, the fracture risk at 10 years showed a median of
11\% for the major fracture and 3.9\% for the hip fracture. FRAX has
rarely been estimated in the publications of other cases.

The other factor involved is the discontinuation of the drug. One of the
reasons DMAB was discontinued came about after reported improvement in
treatment with BMD, leading to the misconception that osteoporosis was
cured. Following this line, the idea of the ``treat to target'' was
developed according to which, when reaching a certain T-score value, the
drug could be suspended, without verifying the results of this
suspension (28--30).This led to the discontinuation of DMAB due to
medical recommendation in 41.1\% of cases. Closely related to this idea
is the concept of therapeutic holidays wrongly applied to DMAB (31,32).
On the other hand, given that the association between the use of
denosumab and osteonecrosis of the jaws has been described (33--35), the
suspension of denosumab was carried out by the dentist's indication in
21.5\% of the patients. Our results coincide with those reported in
other series (7,8,22).

The deleterious effect of DMAB suppression is determined by the sudden
increase in remodeling that can lead to a deterioration in bone strength
and facilitate the appearance of fractures. This fact had been
previously described, although an increase in fractures had not been
observed. After discontinuing DMAB, beta-crosslaps increase
significantly, from a median of 0.071 ng/mL to 0.520 ng/mL (p
\textless{}0.001). To a lesser extent, but also significantly, the
markers of bone formation increase, the P1NP that goes from 25.3 ng/mL
to 101.2 ng/mL, p = 0.006 and osteocalcin from 10.7 ng/mL to 28.1 ng/mL.
This indicates an increase in all bone remodeling in which osteoclastic
activity clearly predominates, as has also been described in other
series (20,36,37). We have not observed changes in serum levels of
creatinine, calcium, phosphorus, total protein, vitamin D, measured as
25-hydroxyvitamin D, or in PTH.

Finally, we carried out a logistic regression analysis to try to
identify which factors could be associated with the presence of a
greater number of fractures, obtaining a statistically significant
association with the time in which denosumab was previously used (p=
0.04).

Among the limitations of our study is the sample size, which is due to
the difficulty in identifying these patients. On the other hand, since
there is no control group, we have not been able to establish what the
clinical, analytical or densitometric factors could be associated with
the appearance of fractures. The strength of the study is determined by
the high number of fractures associated with a full number of
complementary tests.

To sum up, we present a series of 56 patients in which the abrupt
discontinuation of DMAB caused a total of 192 vertebral fractures, the
increase in bone removal probably being manifested through a
considerable increase in biochemical markers of bone remodeling,
especially those of resorption, which causes this effect.

\textbf{Bibliography}

1. Tsourdi E, Rachner TD, Rauner M, Hamann C, Hofbauer LC. Denosumab for
bone diseases: Translating bone biology into targeted therapy. Eur J
Endocrinol. 2011;165(6):833--40.

2. Cummings SR, Martin JS, McClung MR, Siris ES, Eastell R, Reid IR, et
al. Denosumab for prevention of fractures in postmenopausal women with
osteoporosis. N Engl J Med. 2009;361:756--65.

3. Ferrari S, Adachi JD, Lippuner K, Zapalowski C, Miller PD, Reginster
JY, et al. Further reductions in nonvertebral fracture rate with
long-term denosumab treatment in the FREEDOM open-label extension and
influence of hip bone mineral density after 3~years. Osteoporos Int.
2015;26(12):2763--71.

4. Black DM, Reid IR, Cauley JA, Cosman F, Leung PC, Lakatos P, et al.
The effect of 6 versus 9 years of zoledronic acid treatment in
osteoporosis: A randomized second extension to the HORIZON-pivotal
fracture trial (PFT). J Bone Miner Res. 2015;30(5):934--44.

5. Popp AW, Varathan N, Buffat H, Senn C, Perrelet R, Lippuner K. Bone
Mineral Density Changes After 1 Year of Denosumab Discontinuation in
Postmenopausal Women with Long-Term Denosumab Treatment for
Osteoporosis. Calcif Tissue Int. 2018;103(1):50--4.

6. Anastasilakis AD, Polyzos SA, Makras P, Aubry-Rozier B, Kaouri S,
Lamy O. Clinical Features of 24 Patients With Rebound-Associated
Vertebral Fractures After Denosumab Discontinuation: Systematic Review
and Additional Cases. J Bone Miner Res. 2017;32(6):1291--6.

7. Gonzalez-Rodriguez E, Aubry-Rozier B, Stoll D, Zaman K, Lamy O. Sixty
spontaneous vertebral fractures after denosumab discontinuation in 15
women with early-stage breast cancer under aromatase inhibitors. Breast
Cancer Res Treat. 2020;179(1):153--9.

8. Lamy O, Gonzalez-Rodriguez E, Stoll D, Hans D, Aubry-Rozier B. Severe
rebound-associated vertebral fractures after denosumab discontinuation:
9 clinical cases report. J Clin Endocrinol Metab. 2017;102(2):354--8.

9. Tripto-Shkolnik L, Rouach V, Marcus Y, Rotman-Pikielny P, Benbassat
C, Vered I. Vertebral Fractures Following Denosumab Discontinuation in
Patients with Prolonged Exposure to Bisphosphonates. Calcif Tissue Int.
2018;103(1):44--9.

10. Sosa Henríquez M, Gómez de Tejada Romero MJ, Escudero-Socorro M,
Torregrosa Suau O. Hip fractures following denosumab discontinuation:
three clinical cases reports. J R Soc Med. 2019;112(11):472--5.

11. Niimi R, Kono T, Nishihara A, Hasegawa M, Kono T, Sudo A. Second
rebound-associated vertebral fractures after denosumab discontinuation.
Arch Osteoporos. 2020;15(1):10--2.

12. Genant HK, Wu CY, van Kuijk C, Nevitt MC. Vertebral fracture
assessment using a semiquantitative technique. J Bone Miner Res.
1993;8(9):1137--48.

13. World Medical Association. World Medical Association Declaration of
Helsinki. Ethical Principles for Medical Research Involving Human
Subjects. JAMA. 2013;310(20):2013--6.

14. Fernández Fernández E, Benavent Núñez D, Bonilla Hernán G, Monjo
Henry I, García Carazo S, Bernad Pineda M, et al. Fracturas vertebrales
múltiples tras la suspensión de tratamiento con denosumab: serie de diez
casos. Reumatol Clínica. 2019;

15. Florez H, Ramírez J, Monegal A, Guañabens N, Peris P. Spontaneous
vertebral fractures after denosumab discontinuation: A case collection
and review of the literature. Semin Arthritis Rheum.
2019;49(2):197--203.

16. Tripto-Shkolnik L, Fund N, Rouach V, Chodick G, Shalev V, Goldshtein
I. Fracture incidence after denosumab discontinuation: Real-world data
from a large healthcare provider. Bone. 2020;130:115150.

17. Iranikhah M, Deas C, Murphy P, Freeman MK. Effects of Denosumab
After Treatment Discontinuation\selectlanguage{english} : A Review of the Literature. Consult
Pharm. 2018;33(3):142--51.

18. Tsourdi E, Langdahl B, Cohen-Solal M, Aubry-Rozier B, Eriksen EF,
Guanabens N, et al. Discontinuation of Denosumab therapy for
osteoporosis: A systematic review and position statement by ECTS. Bone.
2017;105:11--7.

19. Aubry-Rozier B, Gonzalez-Rodriguez E, Stoll D, Lamy O. Severe
spontaneous vertebral fractures after denosumab discontinuation: three
case reports. Osteoporos Int. 2016;27(5):1923--5.

20. Anastasilakis AD, Makras P. Multiple clinical vertebral fractures
following denosumab discontinuation. Osteoporos Int.
2016;27(5):1929--30.

21. Rao SD, Qiu S, Dhaliwal R, Bhadada SK. Letter to the editor: Severe
rebound-associated vertebral fractures after denosumab discontinuation.
J Clin Endocrinol Metab. 2017;102(6):2111.

22. Tripto-Shkolnik L, Rouach V, Marcus Y, Rotman-Pikielny P, Benbassat
C, Vered I. Vertebral Fractures Following Denosumab Discontinuation in
Patients with Prolonged Exposure to Bisphosphonates. Calcif Tissue Int.
2018;103(1):44--9.

23. Niimi R, Kono T, Nishihara A, Hasegawa M, Kono T, Sudo A.
Rebound-associated vertebral fractures after discontinuation of
denosumab for the treatment of maxillitis. Osteoporos Int.
2018;29(3):769--72.

24. Diez-Perez A.The debate over the FRAX scale. Rev Osteoporos Metab
Miner. 2010;2(1):5--6.

25. Kanis JA, Harvey N, Cooper C, Johansson H, Oden A, McCloskey E, et
al. A systematic review of intervention thresholds based on FRAX: A
report prepared for the National Osteoporosis Guideline Group and the
International Osteoporosis Foundation. Arch Osteoporos. 2016;11,25.

26. Kanis JA, McCloskey E V., Johansson H, Oden A, Strom O, Borgstrom F.
Development and use of FRAX(r) in osteoporosis. Osteoporos Int.
2010;21(Suppl 2):407--13.

27. Tosteson ANA, Iii LJM, Dawson-hughes B, Baim S, Favus J, Khosla S,
et al. Cost-effective Osteoporosis Treatment Thresholds: The United
States Perspective From the National Osteoporosis Foundation Guide
Committee. Osteoporos Int. 2009;19(4):437--47.

28. Lewiecki EM, Cummings SR, Cosman F. Treat-to-target for
osteoporosis: Is now the time? J Clin Endocrinol Metab.
2013;98(3):946--53.

29. Garber AJ. Treat-to-target trials: Uses, interpretation and review
of concepts. Diabetes, Obes Metab. 2014;16(3):193--205.

30. Nogues X, Nolla JM, Casado E, Jodar E, Munoz-Torres M, Quesada-Gomez
JM, et al. Spanish consensus on treat to target for osteoporosis.
Osteoporos Int. 2018;29(2):489--99.

31. McClung MR. Cancel the denosumab holiday. Osteoporos Int.
2016;27(5):1677--82.

32. Sosa Henriquez M, Gomez de Tejada Romero MJ, Malouf Sierra J.
Clinical case to debate: therapeutic holidays: yes or no? Rev Osteoporos
Metab Miner. 2014;6(2):63--9.

33. Khan AA, Morrison A, Hanley DA, Felsenberg D, McCauley LK, O'Ryan F,
et al. Diagnosis and management of osteonecrosis of the jaw: A
systematic review and international consensus. J Bone Miner Res.
2015;30(1):3--23.

34. Ramirez L, Lopez-Pintor RM, Casanas E, Arriba L de, Hernandez G. New
Non-Bisphosphonate Drugs that Produce Osteonecrosis of the Jaws. Oral
Health Prev Dent. 2015;13(5):385--93.

35. Sosa-Henriquez M, Gomez de Tejada-Romero MJ, Bagan-Sebastian JV,
Diaz-Curiel M, Diez-Perez A, Jodar-Gimeno E, et al. Osteonecrosis of the
jaw. Rev Osteoporos Metab Miner. 2009;1(1):53-61.

36. Zanchetta MB, Boailchuk J, Massari F, Silveira F, Bogado C,
Zanchetta JR, et al. Discontinuation of denosumab and associated
fracture incidence: Analysis from the Fracture Reduction Evaluation of
Denosumab in Osteoporosis Every 6 Months (FREEDOM) Trial. J Bone Miner
Res. 2013;28(12):805--7.

37. Eastell R, Christiansen C, Grauer A, Kutilek S, Libanati C, McClung
MR, et al. Effects of denosumab on bone turnover markers in
postmenopausal osteoporosis. J Bone Miner Res. 2011;26(3):530--7.

\textbf{Table 1. Characteristics of the population studied}\selectlanguage{english}
\begin{longtable}[]{@{}ll@{}}
\toprule
& \selectlanguage{ngerman}\textbf{Media ± SD}\tabularnewline
\midrule
\endhead
Number & 56\tabularnewline
Age (years) & 68.1 \selectlanguage{ngerman}± 8.2\tabularnewline
Weight (kg) & 60.7 \selectlanguage{ngerman}± 12.3\tabularnewline
Height (m) & 1.6 \selectlanguage{ngerman}± 0.1\tabularnewline
BMI (Kg/m\textsuperscript{2}) & 25.1 \selectlanguage{ngerman}± 4.6\tabularnewline
& \textbf{Number (\%)}\tabularnewline
Sex female & 54 (96.4)\tabularnewline
Diabetes mellitus & 3 (5.4)\tabularnewline
Arterial hypertension & 18 (32.1)\tabularnewline
Dyslipemia & 18 (32.1)\tabularnewline
Hypothyroidism & 9 (16.1)\tabularnewline
Concomitant use of calcium and vitamin D & 41 (73.2)\tabularnewline
\emph{Prevalence of fractures before the appearance of multiple
vertebral fractures} & \emph{Prevalence of fractures before the
appearance of multiple vertebral fractures}\tabularnewline
No vertebral fracture & 41 (73.2)\tabularnewline
1 vertebral fracture & 4 (7.1)\tabularnewline
2 vertebral fractures & 2 (3.6)\tabularnewline
3 vertebral fractures & 1 (1.8)\tabularnewline
4 vertebral fractures & 2 (3.6)\tabularnewline
Non-vertebral fractures & 5 (8.9)\tabularnewline
Hip fracture & 1 (1.8)\tabularnewline
\bottomrule
\end{longtable}

Table 2. Ten years risk of fracture (FRAX) after the appearance of
multiple vertebral fractures, number of fractures and data related to
the use and withdrawal of denosumab.\selectlanguage{english}
\begin{longtable}[]{@{}ll@{}}
\toprule
& Median CI 95\%\tabularnewline
\midrule
\endhead
FRAX (Major) pre multiple vertebral fractures & 11.0 (6.1 -
16.0)\tabularnewline
FRAX (Hip) pre multiple vertebral fractures & 3.9 (1.2 -
6.6)\tabularnewline
Time using denosumab (months) & 30.5 (24.0 - 43.5)\tabularnewline
Number of dose (n) & 6.0 (4.0 -- 8.0)\tabularnewline
Time after last dose of denosumab and multiple vertebral fractures
(months) & 11.0 (7.5 - 13.5)\tabularnewline
Number of vertebral fractures after denosumab withdrawal (n) & 3 (2 --
4)\tabularnewline
Number of vertebral fractures accumulated (n) & 192\tabularnewline
\bottomrule
\end{longtable}

Table 3. Reason for denosumab withdrawal\selectlanguage{english}
\begin{longtable}[]{@{}ll@{}}
\toprule
\textbf{Reason} & \textbf{Number (\%)}\tabularnewline
\midrule
\endhead
Medical recommendation & 23 (41.1)\tabularnewline
Dentist recommendation & 12 (21.5)\tabularnewline
Oversight, forgotten & 5 (8.9)\tabularnewline
Fatigue & 5 (8.9)\tabularnewline
Secondary effects & 5 (8.9)\tabularnewline
Others & 6 (10.7)\tabularnewline
\bottomrule
\end{longtable}

Table 4. Biochemical parameters including bone remodeling markers pre
and post denosumab withdrawal and the appearance of multiple vertebral
fractures.\selectlanguage{english}
\begin{longtable}[]{@{}lllll@{}}
\toprule
Parameter & Pre-withdrawal & Post-withdrawal & p value & Quotient
(Post/Pre)\tabularnewline
\midrule
\endhead
Creatinine (mg/dL) & 0.710 (0.660 ; 0.790) & 0.700 (0.600 ; 0.810) &
0.499 & -\tabularnewline
Calcium (mg/dL) & 9.5 (9.2 ; 9.8) & 9.7 (9.2 ; 10.0) & 0.075 &
-\tabularnewline
Phosphorus (mg/dL) & 3.5 (3.125 ; 3.775) & 3.6 (3.25 ; 3.85) & 0.298 &
-\tabularnewline
Total proteins (g/L) & 7.1 (6.9 ; 7.28) & 7.0 (6.6 ; 7.2) & 0.183 &
-\tabularnewline
Betacrosslaps (ng/mL) & 0.071 (0.052 ; 0.312) & 0.520 (0.440 ; 1.090) &
\textbf{\textless{} 0.001} & 14.7 (2.1 ; 19.7)\tabularnewline
P1NP* (ng/mL) & 25.3 (15.1 ; 44.7) & 101.2 (74.2 ; 191) & \textbf{0.006}
& 6.5 (2.7 ; 9.9)\tabularnewline
Osteocalcin (ng/mL) & 10.7 (8.4 ; 14.1) & 28.1 (21.41 ; 33.0) &
\textbf{0.003} & 3 (2.4 ; 3.44)\tabularnewline
Vitamin D** (ng/mL) & 29.7 (25.9 ; 39.8) & 31 (26.4 ; 44.8) & 0.770 &
-\tabularnewline
PTH (pg/mL) & 50.1 (39; 60) & 46.8 (36.6 ; 56.2) & 0.500 &
-\tabularnewline
\bottomrule
\end{longtable}

Data are medians (IQR)

* Type I procolagen amino-terminal peptipe ** 25 hydroxicholecalciferol
(25-HCC)

Table 5. Association of the number of vertebral fractures with each one
of the showed factors, adjusted by age*.\selectlanguage{english}
\begin{longtable}[]{@{}lll@{}}
\toprule
Factor & Relative risk (95\% CI) & p-value\tabularnewline
\midrule
\endhead
Time using denosumab per month & 1.009 (1.000 - 1.017) &
\textbf{0.044}\tabularnewline
Diabetes mellitus & 0.701 (0.319 - 1.541) & 0.381\tabularnewline
Arterial hypertension & 0.856 (0.613 - 1.193) & 0.362\tabularnewline
Dyslipemia & 0.794 (0.574 - 1.098) & 0.169\tabularnewline
Hypothyroidism & 1.054 (0.708 - 1.569) & 0.795\tabularnewline
DXA lumbar spine-before & 2.546 (0.578 - 11.221) & 0.225\tabularnewline
DXA lumbar spine-post & 0.348 (0.087 - 1.394) & 0.144\tabularnewline
Creatinine Post & 0.617 (0.234 - 1.623) & 0.333\tabularnewline
Calcium post & 0.970 (0.900 - 1.046) & 0.433\tabularnewline
Phosphorus Post & 0.973 (0.809 - 1.171) & 0.775\tabularnewline
Total proteins Post & 0.862 (0.598 - 1.243) & 0.431\tabularnewline
\bottomrule
\end{longtable}

(*) Each relative risk was obtained by means of a Poisson regression,
being the dependent variable the number of vertebral fractures and the
covariates, the corresponding factor and the age.

\textbf{Addendum 1. Other researchers:}

Javier Mart\selectlanguage{ngerman}ínez de Victoria Carazo, Daniel Fernández-Reyes, Carmen
García-Ibarbia, Alejandro Domínguez-Regueiro, Mª Jesús Moro-Álvarez,
Miguel Ángel Mangas, Rafael Martín-Helguera, Javier del Pino-Montes,
Olga Martínez, Miguel Ángel Tremiño-Arí, Diego Hernandez-Hernández.

\selectlanguage{english}
\FloatBarrier
\end{document}

