Secondary hyperparathyroidism: Predictors and relationship with vitamin D status, bone turnover markers and bone mineral density.

INTRODUCTION: Secondary hyperparathyroidism (SHPT) has adverse implications for bone health but is relatively understudied. In this study we examine the prevalence and determinants of SHPT and describe the relationship of SHPT with bone turnover markers and bone mineral density (BMD) in older Irish adults. METHOD: Eligible participants (n = 4139) were identified from the Trinity-Ulster-Department of Agriculture (TUDA) study, a cohort of Irish adults aged ≥60 years. Exclusion criteria included an estimated glomerular filtration rate (eGFR) <30 ml/min and serum calcium >2.5 mmol/l to remove hyperparathyroidism due to advanced chronic kidney disease (CKD) and primary hyperparathyroidism respectively. The relationship between SHPT and bone turnover markers and BMD (measured by densitometry) was examined in a subsample (n = 1488). Vitamin D deficiency was defined as 25-hydroxyvitamin D [25 (OH)D] <30 nmol/l. RESULTS: Participants had a mean age of 73.6 ± 7.9 years, 65.1 % were female and 19.4 % were found to be vitamin D deficient. The prevalence of SHPT decreased as vitamin D increased, from 30.6 % in those deficient to 9.8 % in those with 25(OH)D ≥ 50 nmol/l and increased with declining kidney function. In non­calcium supplement users, principal determinants of SHPT were vitamin D deficiency (OR 4.18, CI 3.05-5.73, p < 0.001), eGFR 30-44 ml/min (OR 3.69, CI 2.44-5.57, p < 0.001), loop diuretic use (OR 3.52, CI 2.59-4.79, p < 0.001) and to a lesser extent body mass index (p = 0.001), eGFR 45-59 ml/min (p < 0.001) and 25(OH)D level 30-49 nmol/l (p = 0.002). Similar findings were observed in calcium supplement users, though proton pump inhibitors were also associated with SHPT (OR 1.55, CI 1.08-2.22, p = 0.018) while vitamin D 30-49 nmol/l was not. In participants with SHPT versus those without, bone turnover markers were higher: bone alkaline phosphatase (p = 0.017) and tartrate-resistant acid phosphatase (p = 0.033), whilst there was lower BMD at the neck of femur (0.880 vs. 0.903 g/cm2, p = 0.033) and total hip (0.968 vs. 0.995 g/cm2, P = 0.017). DISCUSSION: The results show that up to one in six older Irish adults had SHPT and this was associated with lower BMD and higher concentrations of bone turnover markers. Both vitamin D deficiency and 25(OH)D level 30-49 nmol/l were important predictors of SHPT. Loop diuretics and PPIs may also increase the risk of SHPT, and their use may need to be carefully considered in this population. Further studies examining the potential impact of these factors on bone health in similar populations to our study sample are warranted.

Knowledge gap in a cross section of Irish general practitioners prescribing denosumab for osteoporosis.

BACKGROUND: Denosumab is commonly used by general practitioners (GPs) in Ireland to treat osteoporosis though drug holidays are not recommended with rebound bone loss and risk of vertebral fractures if stopped. We aimed to investigate GP practice and knowledge regarding denosumab including use and reasons for use, therapy duration, blood monitoring and recommended vitamin D status/calcium intake on treatment, staff administering, methods of recall, delays in receiving injections, management of and awarenes of guidelines if stopped, reasons for stopping and concerns about same. METHODS: GPs were contacted (n = 846) by email and invited to complete an online anonymous survey comprising 25 questions in January 2022. We collated responses and explored for differences between GP principals/trainers and GP trainees. RESULTS: There were 146 responses. Sixty-seven percent were female and 50% were GP principal/trainers. Forty-three percent used denosumab as a first line therapy citing convenience in 32% of cases. Half (50%) envisaged therapy for 3-5 years and 15% lifelong use. A fifth (21%) had no concerns about it being stopped (11% trainors vs 31% trainees, P = 0.002). If stopped, 41% cited opting for a drug holiday with monitoring. Forty percent of GPs gave patients a reminder card for the next injection and 27% had an alert system. CONCLUSION: We identified a knowledge gap in denosumab prescribing among a sample of Irish GPs. Findings suggest a need for education to increase awareness around denosumab use and to consider recall systems in GP practices as suggested elsewhere to ensure persistence with therapy.

Falsely elevated parathyroid hormone in a patient with osteoporosis: a case report and review.

BACKGROUND: Parathyroid hormone (PTH) measurements can be falsely elevated due to the hormone binding to other molecules (macro-PTH) or immunoassay interference with heterophile, human anti-animal or other antibodies. This is rare but could lead to incorrect diagnosis, unnecessary investigations or avoidance of teriparatide treatment. We report a case of falsely high PTH levels due to assay interference and review the literature on cases of spuriously elevated PTH. CASE REPORT: An 87-year-old woman attending our bone health clinic with osteoporosis had persistently elevated PTH (383-784 pg/ml) using the Roche Cobas e801 immunoassay despite having normal serum calcium, phosphate, 25 hydroxyvitamin D (> 50 nmol/l) and eGFR (> 60 ml/min). To rule out falsely elevated PTH, a polyethylene glycol precipitation (PEG) test was performed which recovered less than 10% of the hormone resulting in a normal level. PTH was also tested on a different assay (Atellica Siemens) that identified a result of 27 pg/ml. The findings were consistent with immunoassay interference likely due to heterophile antibodies giving rise to a spuriously high PTH. DISCUSSION: The presence of unexpectedly high PTH levels should alert physicians to the possibility of false results due to assay interference or macro-PTH. This highlights the importance of clinically correlating results and of good communication with the testing laboratory. Here, we present the case of an 87-year-old woman with spuriously elevated PTH levels due to immunoassay interference likely mediated by heterophile antibodies. The presence of unexpectedly high PTH levels should prompt consideration of the possibility of false results due to assay interference or macro-PTH.

The association between proton pump inhibitors and hyperparathyroidism: a potential mechanism for increased fracture-results of a large observational cohort study.

Proton pump inhibitors (PPIs) are associated with increased risk of osteoporotic fracture; however, the mechanism is unclear. PPI users taking calcium supplements were more likely to have hyperparathyroidism compared to non-users (OR 1.56, CI 1.08-2.23, p = 0.018). This highlights the importance of monitoring PPI use, especially in older adults. PURPOSE: Proton pump inhibitors (PPIs) are associated with increased risk of osteoporotic fracture. Hyperparathyroidism may be implicated, but few studies have considered this relationship. This study evaluated the relationship between PPI use and hyperparathyroidism in older adults. METHODS: Participants were from the TUDA study, a large cross-sectional cohort of older Irish adults. Participants with an estimated glomerular filtration rate (eGFR) < 30 ml/min and serum calcium > 2.5 mmol/l were excluded to avoid hyperparathyroidism due to chronic renal disease and primary hyperparathyroidism. Hyperparathyroidism was defined as a parathyroid hormone (PTH) > 65 pg/ml. Multivariate regression models were used to analyse the relationship between PPI use and hyperparathyroidism. RESULTS: A total of 4139 participants met the inclusion criteria, of whom 37.8% (n = 1563) were taking PPI medication. PPI use was identified in 41.4% of calcium supplement users and 35.4% of non-calcium supplement users. Overall, compared to non-users of PPIs, those taking PPIs were older (74.8 vs 72.9 years, p < 0.001) and had a higher prevalence of hyperparathyroidism (17.8 vs 11.0%, p < 0.001). In those taking calcium supplements (but not in non-users), PPI use was significantly associated with hyperparathyroidism (OR 1.56, CI 1.08-2.23, p = 0.018) after adjusting for age, sex, body mass index, serum vitamin D, eGFR, timed-up-and-go, dairy intake, medications, and comorbidities. DISCUSSION: The results are consistent with the hypothesis of PPIs reducing calcium absorption, leading to a rise in PTH which could mediate increased fracture risk. No relationship of PPI use with hyperparathyroidism was observed in non-users of calcium supplements, possibly owing to lower dietary calcium intake. These results highlight the importance of monitoring PPI use, especially in older adults at risk of fracture.

Progressive resistance training in a post-acute, older, inpatient setting: A randomised controlled feasibility study.

OBJECTIVES: Progressive resistance training can successfully target functional decline in healthy older community-dwelling adults. There are concerns about the safety and acceptance of its use in frail older populations. The aim of this study was to evaluate the feasibility of using progressive resistance training in an older, post-acute, inpatient setting. METHODS: A randomised controlled feasibility study was conducted. Appropriate older inpatients undergoing post-acute rehabilitation were recruited. Feasibility measures examined were safety, recruitment, outcome measurement, adherence and retention rates and satisfaction. A range of clinical measures were used to capture changes in body structure and function, activity and participation. Assessments were performed on admission to the study and six weeks later. RESULTS: A sample of 33 patients were included and randomised to the treatment group (n=16) or the control group (n=17). There were no serious adverse events, adherence rates were 63% and retention rates were 82%. While both groups improved between time 1 and 2, there were no significant differences in clinical measures between the groups. CONCLUSION: Progressive resistance training is a safe and acceptable intervention for use with this population. Further work on the effectiveness of progressive resistance training in this setting is now required.

Relapse of postictal psychosis following 14-year symptom-free period.

Neuropsychiatric sequelae in patients with epilepsy have been vastly studied and documented. These may be affective, cognitive or psychotic. Certain risk factors may predispose some epileptics more to these sequelae. In general, good epileptic control may minimize these outcomes. We present in this report, a case of postictal psychosis (PIP), superimposed on delirium, in a 68-year-old woman, with history of a single previous psychotic illness following a cluster of seizures. This report shows a collaborative management of the neuropsychiatric complications of temporal lobe epilepsy (TLE), by the neurology, geriatric medicine and psychiatry teams.