Narcolepsy with cataplexy and pregnancy: a case–control study
The prevalence of narcolepsy with cataplexy is 25–50 per 100 000 individuals, with an incidence of 0.3–0.6 per 100 000 individuals per year (Longstreth et al., 2007). The disease is caused by a deficiency in hypothalamic neurotransmission, through a selective loss of hypocretin‐producing neurons (De Lecea et al., 1998). This very specific mechanism of neural destruction potentially indicates an autoimmune pathogenesis, although the existence of a specific autoantibody has not been demonstrated until now. The best biological marker for human narcolepsy is the reduction of hypocretin in the cerebrospinal fluid (Nishino et al., 2000). Narcolepsy typically begins in the teens and early 20s, but may occur as early as 5 years old or older than 40 years, as with other autoimmune diseases. Despite major advances in understanding the pathogenesis and physiopathology of the disease, many cases remain underdiagnosed. The variability of symptoms and the fact that these appear gradually might contribute to misdiagnosis. Thus, during women's fertility age, pregnancy and NT1 can coexist (Alijotas‐Reig and Esteve‐Valverde, 2017).
The management of pregnancy in patients with narcolepsy including the risk to the mother and the fetus related to the disease is challenging as far as the medication is concerned (Hoover‐Stevens and Kovaceic‐Ristanovic, 2000). Congenital abnormalities cannot be excluded. Indeed, how pregnancy affects the course of narcolepsy (and vice versa) has been partially investigated until recently.
A retrospective study in 47 women with narcolepsy, 29 with clear‐cut symptoms prior to pregnancy and 18 after pregnancy, showed no significant differences during pregnancy, or in newborn babies in both groups of women (Maurovich‐Horvat et al., 2010). Despite the small sample size, no severe complications were seen in patients with narcolepsy compared with the women diagnosed with narcolepsy after delivery.
It is important to focus on delivery and possible complications. Cataplexy may interfere with delivery (Williams et al., 2008), but if a Caesarean section is required, it does not seem to cause increased anaesthetic or surgical risks (Dounas et al., 2002; Ping et al., 2007; Soltanifar and Russell, 2010). The discussion issues surrounding pregnant women with narcolepsy include drug therapy and choice of anaesthetic technique. Patients with narcolepsy and apneic episodes might be at risk if general anaesthesia is used (Wise et al., 2006).
Thorpy et al. (2013) and Thorpy and Dauvilliers (2014) have reported the results of a survey of narcolepsy specialists from around the world that focused on clinical experience in the management of narcolepsy at the time of the conception, during pregnancy and while breastfeeding. Although there is insufficient evidence, the findings suggest that the perceived risks of taking narcolepsy medication during pregnancy are overestimated, as the risk for teratogenic effects from narcolepsy medications in therapeutic doses and based on current data could be essentially non‐existent. The need for discontinuation must be fully explained to each patient. The patient and her physician together, depending on estimate risks and benefits of the treatment, must decide withdrawal or continuation of therapy (Hoque and Chesson 2008). The patients decided to stop medication during the first trimester according to specialist advice; however, they could not remember specifically in which week or month. The obstetrician will be informed about the narcolepsy with cataplexy, the symptoms of the patient and the medication.