Association of Age at Menarche with Body Mass Index, Age of Asthma Onset, and Asthma Severity Nora Kabil MD1, Randall M. Goldblum MD2, Terumi Midoro-Horiuti MD, PhD2 Department of Pediatrics1, Clinical and Experimental Immunology and Infectious Disease2 University of Texas Medical Branch, Galveston, Texas, USA Abstract Results Previous studies have shown that during childhood, asthma is more prevalent in boys; however after puberty asthma rates increase in girls. Evidence indicates sex steroid hormones in females may play an influential role in the variation of asthma susceptibility by sex. These findings are consistent with estrogen and/or progestin playing a role in asthma incidence after puberty. During the last century, the median age at menarche has decreased from 16-17 years to less than 13 years. The median age of menarche in the United States is 12.8 years. A few studies in the United States, Canada, and Europe have shown the association between early menarche and asthma. We conducted a retrospective medical chart review of females aged 10-21 years of age seen at the UTMB Pediatric Allergy/Asthma clinic in 2015. Early menarche was defined as menarche occurring ≤ 11 years of age. Correlation coefficients were used to analyze data on body mass index (BMI), age of asthma onset, and asthma severity with age at menarche. A moderate association was shown when comparing age at menarche with body mass index (r= -0.5477, p < 0.005). A weak association was shown when comparing age at menarche with age of asthma onset (r= -0.17169, p < 0.05) and asthma severity (r= -0.26761, p < 0.005). These findings support the hypothesis that early menarche is associated with an elevated BMI, adult onset asthma, and severe asthma. Figure 1. Association of Age at Menarche with Body Mass Index Figure 2. Association of Age at Menarche with Age of Asthma Onset Background Asthma is one of the most common chronic childhood diseases. An estimated 10.5 million children in the United States have been diagnosed with asthma in their lifetime. Of the 10.5 million, 7.1 million children suffer from asthma. In 2007, asthma cost the United States approximately $56 billion dollars in medical costs, lost school and work days, and early deaths. In 2008, more than half of children who had an asthma attack missed school. On average, 4 days of school were missed. The objective of this study is to examine the association of age at menarche with BMI, age of asthma onset, and asthma severity. Figure 3. Association of Age of Menarche with Asthma Severity Description of Study Study participants (n=119) were selected from among females seen at the UTMB Pediatric Allergy/Asthma clinic in 2015. A retrospective electronic medical record chart review was conducted and information on BMI, age at menarche, age at asthma onset, and asthma severity was collected. Early menarche was defined as menarche occurring ≤ 11 years of age. BMI was categorized into underweight (BMI <18.5 kg/m2), normal (BMI 18.5-24.9 kg/m2), overweight (BMI 25-29.9 kg/m2), and obese (BMI ≥30 kg/m2). Adult onset asthma was defined as asthma occurring after age of menarche. Asthma severity was categorized into intermittent asthma, mild persistent asthma, moderate persistent asthma, and severe persistent asthma. Correlation coefficients were used to analyze data on BMI, age of asthma onset, and asthma severity with age at menarche. Figure 4. Correlation Between Age at Menarche with Body Mass Index (r = - 0.5477) Figure 5. Correlation Between Age at Menarche with Age of Asthma Onset (r = - 0.17169) Table 1. Demographic characteristics and risk factors of study participants Demographics n= % Age group, y   10-14 61 51.3 15-20 56 47 21 2 1.7 BMI (kg/m2) < 18.5 17 14.3 18.5-24.9 50 42 25-29.9 31 26.1 ≥ 30 17.6 Race/Ethnicity NonHispanic White 29 24.4 Hispanic White 43 36.1 African American 46 38.7 Other 1 0.8 Physical Activity Yes 28 23.5 No 91 76.5 Smoking Self 4 3.4 Passive None 72 60.5 Age at Menarche, y Premenarchal 22 18.5 ≤10 15 12.6 11 25 12 51 42.9 13 6 5 Cycle length group, days ≤ 24 25-30 31-35 ≥ 36 4.2 N/A 40 33.6 OCP, injections, and implants 19 16 100 84 Other allergic diseases Allergic Rhinitis 93 78.2 Atopy/Eczema 37 31.1 Food Allergies 10.9 Parental Asthma 90 75.6 Figure 6. Correlation Between Age at Menarche with Asthma Severity (r = - 0.26761) Conclusions Early age at menarche is associated with an elevated BMI. Early age at menarche is associated with adult onset asthma. Early age at menarche is associated with severe asthma. These findings provide partial insight into the rapid increase in asthma rates, which coincides with declining trends in menarcheal age. Therefore, we recommend promoting physical activity and nutrition counseling at a young age. Further studies within different contexts are needed to assess the generalizability of the these findings. References Salam MT, Wenten M, Gilliland FD. Endogenous and exogenous sex steroid hormones and asthma and wheeze in young women. J Allergy Clin Immunol. 2006; 117(5):1001–1007. Fida NG, Williams MA, Daniel A Enquobahrie (2012) Association of Age at Menarche and Menstrual Characteristics with Adult Onset Asthma among Reproductive Age Women. Reprod Sys Sexual Disorders 1:111. doi:10.4172/2161-038X.1000111 Al-Sahab B, Hamadeh MJ, Ardern CI, Tamim H (2011) Early menarche predicts incidence of asthma in early adulthood. Am J Epidemiol 173: 64-70. Macsali F, Real FG, Plana E, Sunyer J, Anto J, et al. (2011) Early age at menarche, lung function, and adult asthma. Am J Respir Crit Care Med 183: 8-14. Varraso R, Siroux V, Maccario J, et al. Asthma severity is associated with body mass index and early menarche in women. Am J Respir Crit Care Med. 2005; 171(4):334–339. Results Among study participants, 33% were considered to have early menarche. A moderate association was shown when comparing body mass index with age at menarche (r= -0.5477, p < 0.005). A weak association was shown when comparing age at menarche with age of asthma onset (r= -0.17169, p < 0.05) and asthma severity (r= - 0.26761, p < 0.005). Texas Pediatric Society Electronic Poster Contest Insert Program or Hospital Logo