Acute neurological symptoms secondary to hypomagnesemia induced by proton pump inhibitors: a case series

Movement Disorders and Other Neurologic Impairment Associated With Hypomagnesemia: A Systematic Review

Purpose of Review

The objective of this study was to explore the clinical spectrum of movement disorders and associated neurologic findings in hypomagnesemia and challenges in diagnosis and treatment.

Recent Findings

Sixty patients were identified in the literature for analysis. Movement disorders observed were postural tremor (23.3%, n = 14), resting tremor (8.3%, n = 5), intention tremor (10%, n = 6), ataxia involving the trunk (48.3%, n = 29) or limbs (25%, n = 15) and dysarthria (21.7%, n = 13), athetosis (8.3%, n = 5), myoclonus (6.7%, n = 4), and chorea (1.8%, n = 1). Symptoms may be accompanied by downbeat nystagmus, tetany, drowsiness, vertigo, and proximal muscle weakness. Residual deficits were noted in 16 (26.67%) patients. Serum magnesium was 1.3 mg/dL or lower in 53 patients (88.3%). Imaging findings include bilateral cerebellar (20%, n = 11) and vermis hyperintensities (9.09%, n = 5) and normal imaging. Proton pump inhibitors are the commonest etiology.

Summary

The movement disorders linked with hypomagnesemia can be associated with varied neurologic symptoms. A high degree of suspicion will enable early diagnosis to prevent residual deficits.

Proton-pump inhibitor use amongst patients with severe hypomagnesemia

Introduction: Long-term proton pump inhibitor (PPI) use has been associated with hypomagnesemia. It is unknown how frequently PPI use is implicated in patients with severe hypomagnesemia, and its clinical course or risk factors. Methods: All patients with severe hypomagnesemia from 2013 to 2016 in a tertiary center were assessed for likelihood of PPI-related hypomagnesemia using Naranjo algorithm, and we described the clinical course. The clinical characteristics of each case of PPI-related severe hypomagnesemia was compared with three controls on long-term PPI without hypomagnesemia, to assess for risk factors of developing severe hypomagnesemia. Results: Amongst 53,149 patients with serum magnesium measurements, 360 patients had severe hypomagnesemia (<0.4 mmol/L). 189 of 360 (52.5%) patients had at least possible PPI-related hypomagnesemia (128 possible, 59 probable, two definite). 49 of 189 (24.7%) patients had no other etiology for hypomagnesemia. PPI was stopped in 43 (22.8%) patients. Seventy (37.0%) patients had no indication for long-term PPI use. Hypomagnesemia resolved in most patients after supplementation, but recurrence was higher in patients who continued PPI, 69.7% versus 35.7%, p = 0.009. On multivariate analysis, risk factors for hypomagnesemia were female gender (OR 1.73; 95% CI: 1.17-2.57), diabetes mellitus (OR, 4.62; 95% CI: 3.05-7.00), low BMI (OR, 0.90; 95% CI: 0.86-0.94), high-dose PPI (OR, 1.96; 95% CI: 1.29-2.98), renal impairment (OR, 3.85; 95% CI: 2.58-5.75), and diuretic use (OR, 1.68; 95% CI: 1.09-2.61). Conclusion: In patients with severe hypomagnesemia, clinicians should consider the possibility of PPI-related hypomagnesemia and re-examine the indication for continued PPI use, or consider a lower dose.

The Janus-like Association between Proton Pump Inhibitors and Dementia

Early pharmacoepidemiological studies suggested that Proton Pump Inhibitors (PPIs) might increase the risk of Alzheimer’s Disease (AD) and non-AD related dementias. These findings were supported by preclinical studies, specifically stressing the proamyloidogenic and indirect anticholinergic effects of PPIs. However, further large-scale pharmacoepidemiological studies showed inconsistent results on the association between PPIs and dementia. Pharmacodynamically, these findings might be related to the LXR/RXR-mediated amyloid clearance effect and anti-inflammatory action of PPIs. Further aspects that influence PPI effects on AD are related to patient-specific pharmacokinetic and pharmacogenomic characteristics. In conclusion, a personalized (individualized) medicinal approach is necessary to model and predict the potential harmful or beneficial effects of PPIs in AD and non-AD-related dementias in the future.

Posterior Reversible Encephalopathy Syndrome due to Hypomagnesemia: A Case Report and Literature Review

Background

Hypomagnesemia can cause various unspecific neurological complications, which can lead to diagnostic confusion. One of these complications is the posterior reversible encephalopathy syndrome (PRES), which is extremely uncommon and has been reported only twice in the English-language literature.

Case presentation

We report the case of a 60-year-old man who presented with PRES involving only the cerebellar hemispheres and associated with hypomagnesemia. After excluding all the other possible etiologies of PRES, we started magnesium replacement therapy, which led to a remarkable but fluctuating clinical and chemical improvement. A full recovery with no need for further supplementation was achieved only after discontinuation of a proton pump inhibitor.

Conclusions

This case highlights the role of magnesium in the pathophysiology of PRES; thereby, underlying hypomagnesemia should be considered in every PRES case with unclear etiology.

Proton Pump Inhibitors and Dementia: Physiopathological Mechanisms and Clinical Consequences

Alzheimer's disease (AD) is the most common type of dementia, mainly encompassing cognitive decline in subjects aged ≥65 years. Further, AD is characterized by selective synaptic and neuronal degeneration, vascular dysfunction, and two histopathological features: extracellular amyloid plaques composed of amyloid beta peptide (Aβ) and neurofibrillary tangles formed by hyperphosphorylated tau protein. Dementia and AD are chronic neurodegenerative conditions with a complex physiopathology involving both genetic and environmental factors. Recent clinical studies have shown that proton pump inhibitors (PPIs) are associated with risk of dementia, including AD. However, a recent case-control study reported decreased risk of dementia. PPIs are a widely indicated class of drugs for gastric acid-related disorders, although most older adult users are not treated for the correct indication. Although neurological side effects secondary to PPIs are rare, several preclinical reports indicate that PPIs might increase Aβ levels, interact with tau protein, and affect the neuronal microenvironment through several mechanisms. Considering the controversy between PPI use and dementia risk, as well as both cognitive and neuroprotective effects, the aim of this review is to examine the relationship between PPI use and brain effects from a neurobiological and clinical perspective.

Dementia, cognitive impairment and proton pump inhibitor therapy: A systematic review

BACKGROUND AND AIM

Proton pump inhibitors (PPIs) are among the most widely used medications worldwide. Dementia is an increasingly common cause of disability in older populations. Recent studies have suggested an increased risk of cognitive impairment and dementia diagnosis among people who consume PPIs. This systematic review explores dementia, cognitive impairment, and the use of PPIs.

METHODS

Systematic searches were conducted in the databases of MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), PSYCinfo, Scopus, Web of Science, and ClinicalTrials.gov for articles published from inception to June 30, 2016. Primary outcomes of interest were the use of PPIs and diagnosis of dementia or acute cognitive impairment. Studies conducted on people aged less than 18 years old were excluded. All study designs were eligible for inclusion. Two reviewers independently assessed study quality and extracted data from included studies.

RESULTS

The systematic search strategy and screening process yielded 11 studies for inclusion in the systematic review. Four studies explored PPI use and dementia, and seven studies explored PPI use and acute cognitive impairment. Three of the four studies exploring dementia identified a positive association with PPI use. A positive association was also observed in the majority of studies exploring acute cognitive impairment.

CONCLUSIONS

Based on the current published literature, this systematic review has identified that the reported association between PPI use and dementia is limited by methodological issues and conflicting results. Further longitudinal studies with robust bias limitation are required to explore the use of PPIs and dementia or acute cognitive impairment, and to ascertain the existence of any causal relationships.

Genetics of Magnesium Disorders

Background

Magnesium (Mg²⁺), the second most abundant cation in the cell, is woven into a multitude of cellular functions. Dysmagnesemia is associated with multiple diseases and, when severe, can be life-threatening.

Summary

This review discusses Mg²⁺ homeostasis and function with specific focus on renal Mg²⁺ handling. Intrarenal channels and transporters related to Mg²⁺ absorption are discussed. Unraveling the rare genetic diseases with manifestations of dysmagnesemia has greatly increased our understanding of the complex and intricate regulatory network in the kidney, specifically, functions of tight junction proteins including claudin-14, -16, -19, and -10; apical ion channels including: TRPM6, K_v1.1, and ROMK; small regulatory proteins including AC3 and ANK3; and basolateral proteins including EGF receptor, γ-subunit (FXYD2) of Na-K-ATPase, K_ir4.1, CaSR, CNNM2, and SLC41A. Although our understanding of Mg²⁺ handling of the kidney has expanded considerably in the last two decades, many questions remain. Future studies are needed to elucidate a multitude of unknown aspects of Mg²⁺ handling in the kidney.

Key Message

Understanding rare and genetic diseases of Mg²⁺ dysregulation has expanded our knowledge and furthers the development of strategies for preventing and managing dysmagnesemia.