Study provides insights into narcolepsy treatment and impact on the use of health care in Sweden
Pharmacological treatment trends and degree of care utilization were in focus in an observational study of Swedish patients with narcolepsy.
Narcolepsy, a neurological disorder that affects sleep for rapid eye movement (REM), is a complex disease associated with many comorbidities that can affect patients’ quality of life and have socioeconomic consequences. One recently study published in Acta Neurologica Scandinavica assessed pharmacological treatments and health care use of patients with narcolepsy in Sweden, created a framework for future analyzes and provide insights into healthcare cost trends associated with narcolepsy.
Narcolepsy is characterized by symptoms including daytime sleepiness, disturbed night sleep with nightmares, hypnagogic hallucinations, sleep paralysis and cataplexy – a partial or total loss of muscle tone that is often caused by strong emotions. There are 2 types of narcolepsy. Type 1 is caused by orexin deficiency and includes cataplexy, while type 2 is more common and does not include cataplexy. Narcolepsy is also associated with comorbidities, including obesity, high cholesterol, glucose intolerance, psychiatric disorders, digestive problems, cardiovascular and upper respiratory problems and more.
Pharmaceutical treatment for narcolepsy has been developed in recent years, but treatment was previously symptomatic, or limited to medications to relieve daytime sleepiness or cataplexy, or both. Combination treatments are common, the authors stated. “However, it is important to emphasize that the boundaries between specific effects are not clear. When a patient receives effective treatment for daytime sleepiness, this can also reduce the tendency to develop cataplexy,” they wrote.
A stimulant to relieve daytime sleepiness in combination with an antidepressant to counteract cataplexy is a common example. Sodium oxybate, a drug that relieves daytime sleepiness, cataplexy and nocturnal sleep disorders, has serious side effects ranging from breathing problems to depression and is not reimbursed by the state in Sweden. The study authors also aimed to compare the use of health care between patients receiving standard treatment and those taking sodium oxybate.
The study included 2508 patients diagnosed and treated for narcolepsy. Data from the National Patient Register (NPR), the Swedish Medicines Register and the National Cause of Death Register were used in the study. Pharmacological data from 2005-2017 and data on health care use from 1997-2016 were drawn.
The mean age at diagnosis was 34 years and 56.7% of the cohort were women. The 2508 patients used a total of 3817 drug treatments for narcolepsy. Modafinil, a stimulant to counteract daytime sleepiness, was the most common drug in this cohort, with 1202 (47.9%) of patients prescribing it. This was followed by methylphenidate (33.8%) and amphetamine (26.2%), which are also stimulants. In total, 23.6% of patients used an antidepressant drug.
Study authors also noted that women more often started with modafinil, methylphenidate, amphetamines and antidepressants than men. Approximately 10% of patients used total sodium oxybate, which was prescribed to men and women at a similar rate. Younger patients were more likely to receive sodium oxybate and methylphenidate compared to older patients. A total of 16.5% of the patients in the study group did not receive any of the specified narcolepsy treatments.
Healthcare use data were available for 2493 patients in the study cohort. Patients diagnosed with narcolepsy had an average of 0.2 inpatient visits and 2.6 outpatient visits in the 12 months before the index date. There were data for 2408 patients’ care utilization within 12 months after the index date. On average, narcolepsy patients had 0.3 hospital visits for all reasons and 3.5 outpatient visits for all reasons. Patients prescribed sodium oxybate (n = 238) had an average of 0.1 inpatient visits and 5.6 outpatient visits.
“This may indicate that patients treated with sodium oxybate have more severe symptoms or may have been treated with a more complex pharmacotherapy,” the study authors wrote, noting that sodium oxybate is carefully titrated to allow observation for side effects and may therefore require more visits.
The study is limited by its reliance on NPR data, which does not include data from primary care and may underestimate the actual prevalence, the authors noted. There may also be mild and untreated cases that are not detected.
“This study provides a framework for the evaluation of narcolepsy treatment and health care use in Sweden,” the authors concluded. “Further research is needed to develop the results of the current study and to provide a complete picture of the economic and social consequences.”
Reference
Gauffin H, Fast T, Komkova A, Berntsson S, Boström I, Landtblom A. Narcolepsy treatment in Sweden: an observational study. Acta Neurol Scand. 2022; 145 (2): 185-192. doi: 10.1111 / ane.13532