Cataract And Risk Of Fracture: A Systematic Review And Bayesian Network Meta-Analysis

The progressive reduction in visual quality and acuity associated with cataract may increase the risk of falls and fractures, especially in older adults. Fractures—in particular those involving weight-bearing bones—often require extensive rehabilitation, increase dependence, and can elevate mortality. Although there is growing recognition of a potential link between cataract and fractures, the existing evidence remains inconclusive. To address this gap, we conducted a meta-analysis and a Bayesian network meta-analysis to estimate the odds ratio (OR) and hazard ratio (HR) of bone fracture in phakic subjects with cataract, compared with phakic individuals without cataract and pseudophakic patients.

This is a systematic review and Bayesian network meta-analysis. The literature search strategy was developed using the patient–intervention–comparator–outcome–study type framework, as follows: patients (P), male and female adults worldwide (> 18 years); investigated condition (I), phakic subjects with cataract; comparator (C), phakic subjects without cataract and pseudophakic individuals; outcome (O), any bone fracture; study type (S), retrospective, prospective, and survey studies.

The results of this systematic review and meta-analysis were reported according to the PRISMA guidelines. The study protocol was prospectively registered on the International Prospective Register of Systematic Reviews (ID: CRD42024587477). Four electronic databases were searched from their inception to May 2024: PubMed, EMBASE, Web of Science, and CINAHL. Two independent reviewers performed title and abstract screening, full-text assessment, and study quality appraisal. Bayesian network meta-analysis (NMA) were conducted to assess OR and HR of fracture among the three groups of interest. The GRADE framework was applied to assess the certainty of evidence for all the outcomes analyzed. 

Sixteen articles were included encompassing a population of 4,713,458 subjects and reporting on 284,811 fractures. Bayesian NMAs indicated that subjects with cataracts have an increased odds and hazard of fractures compared to both phakic subjects without cataracts (OR: 3.0 [95% Credible Interval (95% CrI): 2.8 to 3.3]; HR 1.1 [95%CrI: 1.09 to 1.12]) and pseudophakic individuals (OR: 1.7 [95%CrI: 1.6 to 1.8]; HR: 1.28 [95%CrI: 1.24 to 1.31]). Pseudophakic individuals exhibit a 27% reduction in fracture risk compared to phakic individuals with cataract, with 1 fewer fracture event occurring for every 8 pseudophakic subjects. The certainty of evidence was rated as moderate.

These findings support the hypothesis of a potential association between cataract and an increased risk of fractures, which may occur more frequently (i.e., higher OR) and earlier (i.e., higher HR) compared to phakic individuals without cataracts and pseudophakic subjects. Pseudophakic individuals appeared to have nearly a 30% lower fracture risk, with one fewer fracture estimated per eight cataract surgeries. However, the moderate certainty of the evidence suggests that these conclusions should be interpreted with caution. Further research is necessary to explore the underlying mechanisms driving this association, and assess the impact of cataract surgery on the prevention of bone fractures.