[Pharmacogenic osteoporosis beyond cortisone. Proton pump inhibitors, glitazones and diuretics]

Thiazide use and skeletal microstructure: Results from a multi-ethnic study

Background

Thiazide diuretics, a commonly used class of anti-hypertensives, have been associated with increased areal bone mineral density (aBMD). Data regarding effects on fracture are conflicting and no information is available regarding effects on skeletal microstructure and mechanical competence.

Methods

We compared skeletal microstructure, volumetric BMD (vBMD), stiffness and prevalent fractures in current thiazide diuretic users and non-users from a population-based multiethnic cohort of elderly adults age ≥ 65 years (N = 599) with high resolution peripheral quantitative computed tomography (HR-pQCT) and micro-finite element analysis.

Results

Female current thiazide diuretic users had higher weight and BMI and were more likely to be non-Caucasian compared to non-users. There were no differences in age, historical fractures or falls between female users and non-users. Female thiazide users tended to have lower calcium and vitamin d intake compared to non-users. After adjusting for age, weight, race and other covariates, 1/3-radius mean aBMD by dual energy x-ray absorptiometry (DXA) was 3.2% (p = 0.03) higher in female users vs. non-users. By HRpQCT, adjusted mean cortical vBMD was 2.4% (p = 0.03) higher at the radius in female users vs. non-users, but there was no difference in stiffness. DXA results were similar in the subset of Black females. There was no difference in any adjusted aBMD or cortical skeletal parameters by DXA or HRpQCT respectively in males.

Conclusions

Thiazide use was associated with a modestly higher aBMD at the predominantly cortical 1/3-radius site and radial cortical vBMD by HRpQCT in females. The effect on cortical bone may offer skeletal benefits in women taking thiazides for other indications such as hypertension, hypercalciuria or recurrent nephrolithiasis.

High incidence of fracture events in patients with Long-Gap Esophageal Atresia (LGEA): A retrospective review prompting implementation of standardized protocol

PURPOSE

To identify factors associated with an increased risk of fractures in Long-Gap Esophageal Atresia (LGEA) patients. Following implementation of a risk-stratified program, we hypothesized a reduction in fracture incidence within this potentially high-risk population.

METHODS

A retrospective review of LGEA-patients admitted between 2005 and 2014 was conducted. Symptomatic fractures with radiographic confirmation were defined as events. Univariate and multivariable analysis evaluated factors including admission weight-for-age z-score, primary versus secondary Foker process (FP), weight at Foker Stage I, days and episodes of paralysis, number of parenteral nutrition (PN) days, cumulative dose of loop diuretics adjusted for body weight and days exposed, and exposure to non-loop diuretics. A fracture-prevention protocol was initiated in 2012; incidence was evaluated pre and post-intervention.

RESULTS

Fifty-nine patients met inclusion criteria. Twenty-three (39%) patients in the entire cohort incurred at least one fracture during their hospitalization utilizing the Foker process. Given this high percentage, a targeted fracture-prevention protocol was initiated in 2012. Fracture incidence decreased from 48% prior to the protocol to 21% following the protocol (P = 0.046). Several variables that were associated with an increased risk of fractures on univariate analysis included prior esophageal anastomosis attempt (P = 0.008), number of separate episodes of paralysis (P = 0.002), exposure to non-loop diuretics (P = 0.006), cumulative loop diuretic dose (P < 0.001), as well as cumulative loop diuretic over days exposed (P < 0.001). Intensive care unit (ICU) stay (P = 0.002) and total length of hospitalization (P < 0.001) were also significantly longer among patients with a fracture. Number of separate episodes of paralysis was the only independent risk factor for the development of a fracture; patients having more than 3 episodes of paralysis had an estimated risk of fracture 15 times higher than those patients paralyzed only once or twice (O.R. 15.87, 95% C.I.: 1.47-171.23, P = 0.008).

CONCLUSION

Episodes of paralysis appeared to be the most significant risk factor for fractures in patients with LGEA who underwent the Foker procedure. The incidence of symptomatic fractures decreased significantly following implementation of a standardized protocol in this series of LGEA patients with continued prospective evaluation.