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. 2022 Oct;37(13):3283-3288.
doi: 10.1007/s11606-021-07241-2. Epub 2022 Apr 11.

Ankylosing Spondylitis and the Risk of Hip Fractures: a Matched Cohort Study

Avishai M Tsur  1   2   3   4 , Paula David  1   2 , Abdulla Watad  1   2 , Daniel Nissan  5 , Arnon D Cohen  6   7 , Howard Amital  8   9
Affiliations

Ankylosing Spondylitis and the Risk of Hip Fractures: a Matched Cohort Study

Avishai M Tsur et al. J Gen Intern Med. 2022 Oct.

Abstract

Backgrounds: It has been hypothesized that ankylosing spondylitis is associated with an increased risk of incident hip fractures due to osteoporosis and risk of falls but the supporting evidence is limited and mixed.

Objectives: To assess the risk of hip fractures in a large cohort of patients with ankylosing spondylitis compared to a matched cohort.

Design: A retrospective cohort study.

Subjects: Men and women diagnosed with ankylosing spondylitis from 1 January 2002 to 31 December 2018. Matching in a 5:1 ratio was based on age and sex. Follow-up ended on 23 June 2019.

Main measures: Cox regression models adjusting for confounders defined in a causal inference framework were used to determine the hazard ratio for hip fractures.

Key result: The final cohorts included 5,909 ankylosing spondylitis patients and 28,671 matched patients. The ankylosing spondylitis cohort had a mean age of 49 (17) years and was composed of 3,762 (64%) men, 3,638 (62%) patients born in Israel, and 1,532 (26%) patients of low residential socioeconomic status. During 45,388 and 224,192 cumulative person-years of follow-up, the ankylosing spondylitis and matched cohorts had 2.47 and 1.63 cases of hip fractures per 1,000 person-years, respectively. Ankylosing spondylitis patients also developed hip fractures earlier (74 [13] vs. 79 [10] years, p = 0.002). Ankylosing spondylitis was associated with hip fractures in the unadjusted (HR = 1.52, 95% CI [1.23-1.88]) and adjusted (HR = 1.56, 95% CI [1.27-1.93]) models. The association was evident in men (HR = 1.65, 95% CI [1.25-2.18]) and women (HR = 1.48, 95% CI [1.07-2.05]).

Conclusion: This study found that ankylosing spondylitis patients developed hip fractures earlier and more often compared to a matched cohort. This study suggests that ankylosing spondylitis patients might benefit from more proactive screening, mitigation, and prevention of risk factors for hip fractures.

Keywords: ankylosing spondylitis; falls; hip fracture; osteoporosis.

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Conflict of interest statement

The authors report no conflict of interest.

Figures

Fig. 1
Fig. 1
Cohort buildup. Matching in a 5:1 ratio was based on age and sex. In some instances, less than five matches were available.
Fig. 2
Fig. 2
Cumulative incidence of hip fractures in patients with and without ankylosing spondylitis (n = 34,580). Log-rank p < 0.001.
Fig. 3
Fig. 3
The association between ankylosing spondylitis and hip fractures in different Cox models. Residential socioeconomic status was based on residential locality. Smoking status was based on documentation of smoking status before study entry. The hazard ratio is on a logarithmic scale.
See this image and copyright information in PMC

References

    1. Huddleston JM, Whitford KJ. Medical Care of Elderly Patients With Hip Fractures. Mayo Clin Proc. 2001;76(3):295–298. doi: 10.4065/76.3.295. - DOI - PubMed
    1. Lyons AR. Clinical outcomes and treatment of hip fractures. Am J Med. 1997;103(2):S51–S64. doi: 10.1016/S0002-9343(97)90027-9. - DOI - PubMed
    1. Cummings SR, Rubin SM, Black D. The future of hip fractures in the United States. Numbers, costs, and potential effects of postmenopausal estrogen. Clin Orthop Relat Res. 1990;(252):163-166. http://www.ncbi.nlm.nih.gov/pubmed/2302881 - PubMed
    1. Gullberg B, Johnell O, Kanis JA. World-wide Projections for Hip Fracture. Osteoporos Int. 1997;7(5):407–413. doi: 10.1007/PL00004148. - DOI - PubMed
    1. Barnea R, Weiss Y, Abadi-Korek I, Shemer J. The epidemiology and economic burden of hip fractures in Israel. Isr J Health Policy Res. 2018;7(1):38. doi: 10.1186/s13584-018-0235-y. - DOI - PMC - PubMed

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