Cinacalcet-induced hypocalcemia in a cohort of European haemodialysis patients: predictors, therapeutic approaches and outcomes.

BACKGROUND: Calcimimetic treatment of secondary hyperparathyroidism in chronic dialysis patients is often followed by hypocalcemia. METHODS: We investigated the frequency, predictors, consequences and therapeutic responses following cinacalcet-induced hypocalcemia in an incident European hemodialysis cohort of 1068 patients with a cinacalcet prescription. RESULTS: Of 905 normocalcemic patients initiating cinacalcet, 67% developed hypocalcemia within 12 months: 68% mild, 23% moderate, 9% severe. Compared to persistently normocalcemic patients, those with severe hypocalcemia were more often diabetic, overweight, had cardiovascular disease, shorter dialysis vintage, used a catheter dialysis access, had fewer active vitamin-D sterols, and exhibited higher CRP and iPTH and lower calcium levels. Multivariate predictors of hypocalcemia included a catheter for vascular access, low albumin and high iPTH. Generally, no therapeutic intervention to prevent hypocalcemia was taken prior to cinacalcet initiation. After the hypocalcemic event, the most common clinical response was no change of the dialysis or medical regimen. Following the hypocalcemic event, iPTH remained low even in those with severe hypocalcemia. The number of deaths and cardiovascular events did not differ between patients with and without hypocalcemia within six months following cinacalcet initiation. CONCLUSION: Two-thirds of cinacalcet initiated patients experienced hypocalcaemia with 9% being severe. Hypocalcemia was mostly asymptomatic, transient (with and without targeted intervention to correct it) and not associated with an increase in cardiovascular events or deaths.

The economic burden of tuberous sclerosis complex in the UK: A retrospective cohort study in the Clinical Practice Research Datalink.

BACKGROUND: Tuberous sclerosis complex (TSC) is a multi-system genetic disorder characterized by the development of diverse clinical manifestations. The complexity of this disease is likely to result in substantial challenges and costs in disease management throughout the patient's lifetime. This retrospective database study aims to quantify healthcare resources utilized by TSC patients. METHODS: TSC patients in the Clinical Practice Research Datalink linked to the Hospital Episodes Statistics database were identified between January 1987 and June 2013. Analyses were conducted over the most recent 3-year period of data and stratified by pediatric (< 18) and adult patients. Prescriptions, procedures, diagnostic tests, and healthcare encounters were reported in comparison with a matched comparator cohort. Costs and key economic drivers by primary organ system manifestations were also examined. RESULTS: A total of 286 patients with TSC were identified and consistently reported 2-fold greater resource use than the matched presumably healthy controls. Despite this comparatively greater resource use, half of TSC patients did not record any procedures, and 20% of patients did not record any diagnostic tests; however, inpatient hospitalizations were greater for the TSC cohort (3.1 vs 1.3), but length of stay was comparable. TSC patients had costs totaling £12,681 per patient over the 3-year period, a figure 2.7-fold greater than the total costs in the comparator cohort (£4,777). Costs for patients with specific primary manifestations were even greater, with brain manifestations incurring £22,139 per affected patient. Kidney and nervous system manifestations were the main cost drivers. CONCLUSIONS: The economic burden of TSC and its impact on NHS healthcare resources is mostly attributable to the broad spectrum of manifestations that develop within multiple organ systems. TSC patients may benefit from co-ordinated care based on their requirement for high numbers of healthcare visits across specialties.