Khammarnia Mohammad, Siakhulak Fariba Ramezani, Ansari Hossein, Peyvand Mostafa
Ph.D., Assistant Professor, Health Promotion Research Center, Zahedan University of Medical Sciences, Zahedan, Iran.
M.Sc., Department of Epidemiology and Biostatistics, School of Public Health, Health Promotion Research Center, Zahedan University of Medical Sciences, Zahedan, Iran.
Electron Physician. 2018 Feb 25;10(2):6286-6291. doi: 10.19082/6286. eCollection 2018 Feb.
Congenital hypothyroidism (CH) is known as one of the most common preventable cause of mental retardation. This study aimed to determine factors associated with CH in Iran.
This case-control study was conducted on 160 children under one year old in Zahedan in southeast Iran in 2016. The neonates who were born from March 1, 2015 to March 19, 2016 and had undergone a screening program for CH were the study population. The neonates with serum TSH > 10mIu/L and T4 < 6.5 or TSH > 30 mIu/L were considered as a case group. Each case was individually matched for sex, age at birth and place of residence with three neonates with normal TSH and T4 titers as a control group. Data was gathered using a standard checklist and analyzed using SPSS 20 and statistical tests, such as Chi-square and Fisher's exact tests. Multivariable logistic regression analysis was also used to identify independent predictors of CH.
About 25 of the 40 patients with CH (62.5%) were male who, in the univariate analysis, the following explanatory factors had no significant association with CH: history of parental consanguinity, type of delivery, weight at birth, height at birth, age of mother, sampling time, nationality, and birth season (p>0.05). Although, multivariate analysis showed no significant association between the studied factors and risk of CH (p>0.05), the likelihood of CH was greater among neonates born to consanguineous parents (AOR: 1.78, 95% CI: 0.82-3.89), those who were born to lower height at birth (AOR: 1.82, 95% CI: 0.85-3.91), neonates born to mothers younger than 18 years (AOR: 2.43, 95% CI: 0.57-10.29) and those who were born in the summer (AOR: 1.76, 95% CI: 0.57-5.44).
None of the studied factors were predictors for CH. Since consanguineous marriages are frequent in the province, and it may be a major contributory factor, future studies should be conducted on the genetic causes.
先天性甲状腺功能减退症（CH）是已知最常见的可预防的智力发育迟缓病因之一。本研究旨在确定伊朗与CH相关的因素。
2016年在伊朗东南部扎黑丹对160名1岁以下儿童进行了这项病例对照研究。研究对象为2015年3月1日至2016年3月19日出生且接受过CH筛查项目的新生儿。血清促甲状腺激素（TSH）>10mIu/L且甲状腺素（T4）<6.5或TSH>30mIu/L的新生儿被视为病例组。每个病例按性别、出生时年龄和居住地点与三名TSH和T4水平正常的新生儿进行个体匹配，作为对照组。使用标准检查表收集数据，并使用SPSS 20和统计检验（如卡方检验和费舍尔精确检验）进行分析。还采用多变量逻辑回归分析来确定CH的独立预测因素。
40例CH患者中约25例（62.5%）为男性，在单变量分析中，以下解释因素与CH无显著关联：父母近亲结婚史、分娩方式、出生体重、出生身高、母亲年龄、采样时间、国籍和出生季节（p>0.05）。尽管多变量分析显示所研究因素与CH风险之间无显著关联（p>0.05），但近亲结婚的新生儿患CH的可能性更大（比值比[AOR]：1.78，95%置信区间[CI]：0.82 - 3.89），出生时身高较低的新生儿（AOR：1.82，95%CI：0.85 - 3.91），母亲年龄小于18岁的新生儿（AOR：2.43，95%CI：0.57 - 10.29）以及夏季出生的新生儿（AOR：1.76，95%CI：0.57 - 5.44）。
所研究的因素均不是CH的预测因素。由于该省近亲结婚频繁，这可能是一个主要促成因素，未来应针对遗传原因开展研究。
