Anthropometric characteristics and comorbidities in Japanese patients with neurofibromatosis type 1: A single institutional case–control study

Abstract

Neurofibromatosis type 1 (NF1) is a well-known genetic disorder characterized by café-au-lait spots and neurofibromas, but many other clinical characteristics and associated comorbidities also have been reported. This study aimed to characterize NF1 further by investigating its association with anthropometric characteristics and other diseases. We performed a case-control study of 227 NF1 patients (101 male, 126 female) and a randomly selected age- and sex-matched control group of 681 non-NF1 patients (303 male, 378 female) who visited our institution in Japan. We examined adult (≥20 years) height and body mass index (BMI), and, in the total sample, allergic diseases (bronchial asthma [BA], atopic dermatitis [AD] and allergic rhinitis) and other respiratory cardiovascular and psychiatric disorders. In adults, the mean BMI was lower in the NF1 group than in the control group, and was significantly statistically different among men (P = 0.0238). In the whole sample, the prevalences of BA (P = 0.0184), AD (P = 0.0144) and valvular heart disease (P = 0.0166) were significantly greater in the NF1 group than in the control group. To date, no similar research on the BMI or the prevalence of allergic disease in NF1 patients has been reported. Our results suggest that NF1 patients tend to have lower BMI and may have alterations in specific metabolic pathways and altered allergic immunity.

Nutritional, muscular and metabolic characteristics in patients with neurofibromatosis type 1

“…Clinical information is lacking, however, on body mass index (BMI) of NF1 patients and there is currently no consensus about BMI of NF1 patients. We have previously reported that NF1 patients have lower BMI (especially men) than that of other patients with dermatological diseases, although the precise mechanism is yet unclear . In the published work, some reports have identified that muscle size and strength are decreased in NF1 patients and that they have inadequate intake for various nutrients than controls .…”

“…There is no consensus among the few existing studies regarding NF1 and obesity . We previously reported that adult NF1 patients, especially in men, have lower BMI than patients with other dermatological diseases . In the present study, we only selected patients who underwent skin surgery for benign tumors, because such patients were thoroughly screened by blood tests.…”

“…[12][13][14] We previously reported that adult NF1 patients, especially in men, have lower BMI than patients with other dermatological diseases. 7 In the present study, we only selected patients who underwent skin surgery for benign tumors, because such patients were thoroughly screened by blood tests. Therefore, the groups of patients and controls were different from our previous study, with subjects also recruited from another facility.…”

“…We have previously reported that NF1 patients have lower BMI (especially men) than that of other patients with dermatological diseases, although the precise mechanism is yet unclear. 7 In the published work, some reports have identified that muscle size and strength are decreased in NF1 patients 8,9 and that they have inadequate intake for various nutrients than controls. 10 This may explain why NF1 patients are thinner than the general population.…”

Neurofibromin is essential to maintain metabolic function and sustain life in the adult mouse

“…There was no evidence of infection or cardiovascular dysfunction that could explain the acute death. Recent studies show that NF1 patients have a high prevalence of being underweight with short stature accompanied by lower BMI (32)(33)(34). Further studies need to be conducted to assess body composition within NF1 patients that could be underweight due to a decrease in body fat and a similar underlying metabolic condition as compared to this systemic knockout Nf1 model.…”