Investigation Of The Prevalence Of Thyroid Dysfunction In The Middle-age And Elderly Diabetes And Pre-diabetes Populations

IntroductionDiabetes mellitus (DM) is a multi-factor clinical syndrome caused by genetic、 environmental and other reasons, which is mainly characterised by glucose metabolic disorder. Pre-diabetes refers to a high blood glucose status that not reach the DM diagnostic standard, including impaired fasted glucose(IFG)and impaired glucose tolerance (IGT). DM brings great inconvenience and suffering to people life, and makes economic burden. The prevalence of DM and Pre-diabetes kept increasing all over the world.Thyroid Dysfunction (TD) is another kind of clinically common endocrine diseases, which covers four different forms:Hyperthyroidism、Hypothyroidism、Subclinical Hyperthyroidism、Subclinical Hypothyroidism.Studies have found that diabetes and thyroid disorders tend to coexist in patients. Prevalence of thyroid dysfunction in the diabetic population when compared with the normal population is proved higher, especially in subjects with type1diabetes. Studies indicate that unrealized abnormality of thyroid hormone level may be a reason of poorly controlled type2DM. Although so far there is no related large sample epidemiological survey, which compares the incidence of TD in people with normal blood glucose level with that in DM and Pre-diabetes people. We will make it up by analyzing epidemiological survey data of middle aged and elderly people in Ningyang, to have a view of thyroid dysfunction incidence in.diabetes mellitus people and prediabetes people compared with normal population.MethodsIn2011, investigators who had received unified training randomly selected several villages and towns from Tai’an City Ningyang county for epidemiological investigation, there were about11000participants. The investigation was conducted in local hospital and health center. All participants were voluntary and had signed informed consent.Investigators help participant fill out questionnaire, in which age, gender, high,weight, being breast-feeding or not, heart and kidney serious disease history, tumor and surgery history, DM and drug therapy history, thyroid disease and drug therapy history, diet and life style were involved. Participants accepted oral glucose tolerance test (OGTT), to detect fasting plasma glucose (FPG),2h postprandial blood glucose and glycosylated hemoglobin (HbAlc) levels, in addition we detect the serum FT3, FT4, TSH levels. According to elimination standards,finally9743subjects were selected (≥40year). According to the2013American diabetes association (ADA) guidelines, the diagnostic criteria for diabetes:HbAlc≥6.5%, or FPG≥7.0mmol/l, or OGTT2h blood glucose≥11.1mmol/1; Diagnostic criteria for pre-diabetes:HbAlc5.7-6.4%, or FPG5.6-7.0mmol/1, or OGTT2h blood glucose6.8-11.1mmol/1. Thyroid dysfunction diagnostic criteria is as follows: hyperthyroidism:TSH<0.27mmol/1, FT3>6.8mmol/l or FT4>12mmol/1; Subclinical thyroid hyperthyroidism:TSH<0.27mmol/1, FT3, FT4both in normal range; Hypothyroidism:TSH>4.2mmol/1and FT4<12mmo/1; Subclinical hypothyroidism:TSH>4.2mmol/1, and FT4is normal range.Firstly we had a view of the incidence of DM, Pre-diadetes, and TD in our participants, then divided them into groups by gender and age, analyze and compare respectively. Divide participants into3groups by FPG,2h glucose and HbAlc level:DM group, Pre-diabetes group and normal glucose group, to compare incidence of TD and FT3、FT4、TSH level. We used SPSS statistical software for data analysis, table chi-square, R*C sequence table chi-square and other inspection methods were used, with P<0.05for statistically significant.ResultsThe incidence of DM in middle aged and elderly people in Ningyang is26.60%, which of Pre-diabetes is59.15%, higher than domestic existing conclusions. In middle aged and elderly people, the incidence of DM in male is higher than in female,while the incidence of Pre-diabetes is the opposite. For those younger than 70, the risk of DM increases along with the age growth, but when they are70or older, this trend dispares.The incidence of TD in middle aged and elderly people in Ningyang is15.24%, and the incidence of Subclinical Hypothyroidism is12.81, highest of the four. The risk of Hypothyroidism and Subclinical Hypothyroidism in male is smaller than in female. As the age growing, the thyroid dysfunction declines.The differences of thyroid dysfunction incidence between diabetes group、 prediabetes group and normal population have no statistical significance. But the analysis of FT3, FT4, and TSH level indicates that the FT4level of DM group is higher than non-DM people, which can be seen as evidence of the influence of DM on thyroid function.