Ehlers-Danlos Syndrome and Narcolepsy: An Incidental Relationship?

A 12-year-old African-American female presented with a complaint of ES (Epworth Sleepiness Scale ^ESS = 15), with an onset of about two years prior to her initial evaluation. Her typical sleep patterns included going to sleep at 4pm and waking up at 6am. She would typically come home from school preferring to sleep rather than eat; her mother’s attempts to wake her up for dinner were often unsuccessful. She would sometimes fall asleep during school, usually 5 times per day for about 15 minutes, at which time her teacher would wake her up. Eye lid drooping was noticed when she cried as well as when she laughed hard. This was sometimes associated with dizziness. The patient also experienced hypnagogic hallucination described as a “black shadow at the corner of the room”. She reported infrequent sleep paralysis occurring once a month. Her swiss narcolepsy scale is -88 suggestive of narcolepsy with cataplexy.

The patient’s body mass index ^BMI was within the normal range for her height (weight=49.40 kg, height=1.68 m, BMI=17.6) and aside from history of delayed speech requiring speech therapy at age 3, her neurological and other medical history was unremarkable. During examination, it was noticed that the patient also had elastic skin, long fingers, extensibility of the elbow, and symptoms of postural orthostatic tachycardia syndrome (POTS) with feeling dizzy if she was lying down and stood up too fast. She was referred to geneticist who diagnosed her with EDS. Leg length discrepancy, arachnodactyly, pes planus of both feet, tall stature and valgus deformity of the great toe were also noted. Genetic testing revealed a heterozygous variant in the COL9A2 gene (c.1061C>T). Her echocardiogram showed mild to moderate mitral insufficiency.

Due to suspected narcolepsy, polysomnography (PSG) with MSLT was conducted. At the time of the evaluation, she was not taking any medications other than multivitamins and an iron supplement. Results showed a normal PSG (total sleep time ^TST=438.5 minutes; sleep efficiency ^SE=90.1; REM latency=234.0 minutes) with no OSA (apnea hypopnea index ^AHI was 1.6). MSLT showed an average sleep latency of 2:08 minutes, with three SOREMs confirming the presence of narcolepsy. While her sleep during PSG was about 7 hours, that is not unusual given the routine starting of the procedure at around 8pm, with about an hour for PSG setting and the arousal at 6am. Although neuroimaging and urine drug screen were not performed, both patient and her mother denied drug usage. Due to the lack of centers testing for cerebrospinal fluid (CSF) hypocretin, this investigation was not performed.

Initially, daily extended release amphetamine/dextroamphetamine 10mg was initiated; however, the patient continued to feel tired during the day and even more so at 15mg. Her prescription was switched to long-acting methylphenidate hydrochloride 27mg, but initially helpful, it stopped working after two months. Lisdexamfetamine 40mg was also tried but discontinued due to palpitations and chest pain. A retrial of the long-acting mixed amphetamine salts at a dose of 15mg yielded a good response.

A 15 year-old Caucasian female was referred by her psychiatrist due to difficulty sleeping at night and ES. She struggled with depression after her father died in his sleep when she was seven. Although she would only see him on the weekends, they were close to each other. Around the anniversary of his death, she would often struggle more with her depression, having crying spells. Her appetite has been decreased and she lost 10 pounds over a six month duration, a year prior to her presentation. She was placed on sertraline 50mg daily by her psychiatrist and reported efficacy. Other stressors included losing her paternal grandparents and being bullied in school.

Her initial insomnia started when she was nine, after the death of her father. However, it later improved without treatment. It worsened again few months prior to her presentation, possibly precipitated by concussion associated with loss of consciousness while cheerleading. Her grades deteriorated to failing after being a B/C student. She reported going to bed around 10:30 or 11 pm, sleeping for about 2 hours at a time with at least 3-4 arousals per night. On weekdays, she would wake up at 5 am but on weekends would sometimes sleep until 3 pm if her mom did not disturb her. Due to her intermittent snoring at night, waking up gasping for air and trouble sleeping, PSG was conducted and showed an AHI of 11.3, with lowest oxygen at 85%. This highlighted moderate to severe OSA and due to her large adenoids and tonsils, she had adenotonsillectomy. However, there was minimal change in her signs and symptoms. Over the course of treatment, medication trials included melatonin at 5mg, clonidine 0.1mg, doxepine at 20mg and even zolpidem 2.5mg nightly; all were unsuccessful. She complained of leg cramps and uncomfortable sensations mainly in her thighs. This was improved by rocking. In addition, there was family history of restless leg syndrome (RLS) in her paternal grandfather; thus, her ferritin level was tested and found to be at 22, and iron repletion was initiated. After normalization of the iron stores and due to continued RLS symptoms, ropinirole initially at 0.25mg was titrated slowly over a 2 month period to 2mg nightly which partially helped. Her initial PSG revealed mild to moderate periodic limb movements (PLMS) and a repeat sleep study after adjustment of medication resulted in a normal PLMS. Her blood work including complete blood work (CBC), basic metabolic panel (BMP) and thyroid stimulating hormone (TSH) were all within normal range. Due to her previous concussion history, magnetic resonance imagining of the head was performed and showed no abnormalities.

Due to her reported 14-16 hours of sleep, confirmed by fitbit data even in the two weeks prior to her PSG, narcolepsy was suspected. Symptoms consisted of weakness in her leg muscles and thighs when crying, followed by a feeling of needing to sit and later having to sleep (once every few weeks). Hypnagogic hallucination of seeing “black stuff” as if something went across the room occurring every few nights were also noted. However, no sleep paralysis was reported.

The patient’s BMI was within normal range (height=1.65 m, weight=55.34 kg, BMI=20.3) and mental status exam revealed a well-kempt, cooperative young woman with depressed mood and slightly diminished alertness. In addition, examination revealed hyperextension of the fingers on both hands. She also had a history of joint pain, joint dislocation and frequent sprains and fractures as well overall discomfort with a need to stretch and “crack” various joints for relief. Other symptoms include orthostatic dizziness, mild scoliosis, and vomiting. She was referred to genetics where she was diagnosed with Ehlers Danlos syndrome – hypermobile type. She had previously had a visual field and neurological exam done as part of a post-concussion evaluation, which noted no visual field defects or neurological abnormalities. Her second PSG was conducted after 4 months after surgery showing TST was 384 min, SE at 88%, AHI 1.6 and lowest oxygen was 96%. Although there was no snoring, frequent arousals were noticed. The third PSG with MSLT was conducted showing TST of 290.5 with REM latency of 57.5, SL of 2.9, and AHI was 3.1 with no oxygen desaturations. However, her arousal index was 24. Her MSLT showed moderate daytime hypersomnolence (average sleep latency of 6:45 minutes) with two SOREMs consistent with narcolepsy. Prior to the PSG, the patient was medicated with certerizine HCl, cholecalciferol, ferrous sulfate, hydroxyzine pamoate, mometasone furoate, Montelukast sodium, norethidrone ethinyl estradiol, omeprazole, ropinirole HCl, sertraline HCl, and zolpidem tartrate. However, to avoid the effects of her psychotropic medications on the sleep study, sertraline and zolpidem were discontinued two weeks prior to the study. It is not clear of why her third study showed a sleep duration of about 5 hours, compared to the previously conducted studies which were more than six.

Due to the confirmed narcolepsy, extended release mixed amphetamine salts at a dose of 10mg daily was initiated and showed significant improvement of symptoms. Although initially she had significant missed school days due to ES, after medication initiation, she did not miss any days and started to function better. The dose was later increased to 15mg because it was wearing off around noon. Her sleep pattern improved. She reported going to sleep at 10 pm after her cheerleading practice which occurred between 6-8:30 pm. She would go to sleep fast and would wake up at 6:20 am. Although she continued to nap daily (up to 2-3 hours), her daytime alertness improved, as did her grades.