Mortality in neurofibromatosis 1: An analysis using US death certificates

Although neurofibromatosis 1 (NF1) is a relatively common autosomal dominan t condition, information about its effect on mortality is limited. We used Multiple-Cause Mortality Files, compiled from U.S. death certificates by th e National Center for Health Statistics, for 1983 through 1997. We identifi ed 3,770 cases of presumed NF1 among 32,722,122 deaths in the United States , a frequency of 1/8,700, which is one-third to one-half the estimated prev alence. Mean and median ages at death for persons with NF1 were 54.4 and 59 years, respectively, compared with 70.1 and 74 years in the general popula tion. Results of proportionate mortality ratio (PMR) analyses showed that p ersons with NF1 were 34 times more likely (PMR = 34.3, 95% confidence inter val [CI] 30.8-38.0) to have a malignant connective or other soft-tissue neo plasm listed on their death certificates than were persons without NF1. Ove rall, persons with NF1 were 1.2 times more likely than expected (PMR = 1.21 , 95% CI 1.14-1.28) to have a malignant neoplasm listed on their death cert ificates, but the PMR was 6.07 (95% CI 4.88-7.45) for persons who died at 1 0-19 years of age and was 4.93 (95% CI 4.14-5.82) for those who died at 20- 29 years of age. Similarly, vascular disease was recorded more often than e xpected on death certificates of persons with NF1 who died at <30 years of age (PMR = 3.26, 95% CI 1.31-6.71 at age <10 years; PMR = 2.68, 95% CI 1.38 -4.68 at age 10-19 years; and PMR = 2.25, 95% CI 1.46-3.32 at 20-29 years) but not in older persons. This study PMR supports previous findings of decr eased life expectancy for persons with NF1 and, within the limitations of d eath certificates, provides population-based data about NF1 morbidity and m ortality that are useful to clinicians caring for patients with NF1.