European Journal of Cardiovascular Medicine

Hypothyroidism and Type 2 Diabetes Mellitus (T2DM) are two prevalent endocrine disorders that significantly impact global health. Both conditions have a considerable burden on individuals and healthcare systems, and their association has been a subject of growing interest among researchers and clinicians. The intricate interplay between thyroid function and glucose metabolism has been a focus of numerous studies, with emerging evidence suggesting a bidirectional relationship between hypothyroidism and T2DM.1,2

The coexistence of hypothyroidism and T2DM poses unique challenges in clinical management, as these conditions share common risk factors and may influence each other's pathophysiology. Hypothyroidism, characterized by an inadequate production of thyroid hormones, can lead to alterations in glucose homeostasis, insulin resistance, and impaired insulin secretion. Conversely, T2DM, characterized by insulin resistance and impaired insulin secretion, may exert effects on thyroid function.3,4

Several studies have explored the association between hypothyroidism and T2DM, yielding diverse findings that underscore the complexity of their relationship. Some investigations suggest a higher prevalence of hypothyroidism in individuals with T2DM, while others report an increased risk of T2DM in patients with hypothyroidism. However, the precise mechanisms underlying this association remain incompletely understood.3-5

This study aims to contribute to the existing body of knowledge by investigating the association of hypothyroidism in patients with T2DM at Hind Institute of Medical Sciences, Sitapur, Mau, Ataria, Uttar Pradesh. Our primary objective is to assess the prevalence of hypothyroidism in a cohort of T2DM patients attending a tertiary care center. Additionally, we seek to explore potential risk factors, clinical correlations, and the impact of coexisting hypothyroidism on the management and outcomes of T2DM in this population.

The importance of understanding the association between hypothyroidism and T2DM is underscored by its implications for patient care and public health. A clearer understanding of this relationship could inform targeted screening strategies, optimize therapeutic interventions, and improve overall outcomes in individuals affected by these coexisting endocrine disorders

Study Design: A cross-sectional design was employed to investigate the association of hypothyroidism in patients with Type 2 Diabetes Mellitus (T2DM) at Hind Institute of Medical Sciences, Sitapur, Mau, Ataria, Uttar Pradesh. This design was well-suited for examining the prevalence of conditions in a specific population at a given point in time.

Study Setting: The research was conducted at the Hind Institute of Medical Sciences, a tertiary care center in Uttar Pradesh. The choice of this setting ensured access to a diverse patient population and comprehensive medical records.

Sample Size Calculation: The sample size was determined based on statistical considerations to achieve adequate power for detecting the prevalence of hypothyroidism in T2DM patients. A sample size of 50 participants was targeted, ensuring a balance between feasibility and statistical robustness.

Participant Selection: Participants were recruited from the pool of T2DM patients attending the outpatient department of the Hind Institute of Medical Sciences. Inclusion criteria encompassed adult individuals (18 years and above) diagnosed with T2DM. Patients with a known history of thyroid disorders and those on thyroid medication were included.

Data Collection:

1. Clinical Assessment: Each participant underwent a comprehensive clinical assessment, including demographic details, medical history, and anthropometric measurements (e.g., weight, height, waist circumference).
2. Thyroid Function Tests: Blood samples were collected to assess thyroid function, including serum levels of thyroid-stimulating hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3).
3. Diabetes Parameters: Glycemic control in T2DM patients was evaluated through measurements of fasting blood glucose (FBG) and glycosylated hemoglobin (HbA1c).
4. Other Relevant Variables: Additional data on lifestyle factors, comorbidities, and medication history were collected through structured interviews and medical records.

Ethical Considerations: The study adhered to ethical principles outlined in the Declaration of Helsinki. Ethical approval was sought from the Institutional Review Board of Hind Institute of Medical Sciences before initiating data collection. Informed consent was obtained from all participants, ensuring confidentiality and the right to withdraw at any stage.

Data Analysis: Descriptive statistics were used to summarize demographic and clinical characteristics of the study population. The prevalence of hypothyroidism in T2DM patients was calculated, and subgroup analyses explored potential associations between hypothyroidism and various parameters. Statistical significance was determined using appropriate tests, and a p-value of <0.05 was considered statistically significant.

Quality Control: Rigorous quality control measures were implemented throughout the study, including standardized data collection procedures, regular training sessions for data collectors, and periodic review of collected data to identify and rectify discrepancies.

This table-1 provides an overview of the demographic profile of the study participants. The sample consists of 50 individuals with an equal distribution between males and females. The average age of the participants is 54.6 years, with a standard deviation of 8.2. The mean BMI is 27.3 kg/m², and the average duration of Type 2 Diabetes Mellitus (T2DM) is 7.8 years

Table 1: Demographic Characteristics of Study Participants

This table outlines the prevalence of different thyroid statuses among the T2DM participants. The majority (70%) are euthyroid, while 20% exhibit hypothyroidism, 6% hyperthyroidism, and 4% subclinical hypothyroidism. Importantly, no participants have subclinical hyperthyroidism.

Table 2: Prevalence of Hypothyroidism in T2DM Patients

These are the results of thyroid function tests, providing insights into the mean values of key parameters. The average Thyroid Stimulating Hormone (TSH) level is 2.5 mIU/L, Free Thyroxine (FT4) is 1.2 ng/dL, and Free Triiodothyronine (FT3) is 2.8 pg/mL.

Table 3: Thyroid Function Test Results in T2DM Patients

This table-4 compares glycemic parameters between T2DM patients with and without hypothyroidism. Euthyroid individuals have a significantly lower fasting blood glucose (FBG) level (130 mg/dL) compared to hypothyroid individuals (145 mg/dL), with a p-value of 0.042. Similarly, the HbA1c level is significantly higher in hypothyroid individuals (7.2%) compared to euthyroid individuals (6.5%) with a p-value of 0.018.

Table 4: Glycemic Control in T2DM Patients with and without Hypothyroidism

This table-5 explores the association between hypothyroidism and various clinical parameters. The odds ratio (OR) indicates the likelihood of certain conditions based on the presence of hypothyroidism. Individuals over 50 years of age have a 2.1 times higher odds of having hypothyroidism compared to those under 50. Similarly, participants with a BMI of 25 or higher have 1.8 times higher odds of having hypothyroidism. Additionally, those with T2DM duration over 5 years have 3.5 times higher odds of hypothyroidism.

Table 5: Association Between Hypothyroidism and Clinical Parameters

This table-6 details the medication usage pattern in T2DM patients with and without hypothyroidism. Notably, all hypothyroid individuals (100%) are on thyroid medication, while 80% of euthyroid individuals are on oral antidiabetic agents. The differences in medication usage are statistically significant.

Table 6: Medication Usage in T2DM Patients with Hypothyroidism

This table-7 explores the correlation between thyroid hormone levels and the duration of T2DM. TSH shows a positive correlation (0.25) with a p-value of 0.042, indicating that as T2DM duration increases, TSH levels also tend to increase. However, FT4 and FT3 do not show significant correlations with T2DM duration.

Table 7: Correlation Between Thyroid Hormone Levels and Diabetes Duration

Hypothyroidism and Type 2 Diabetes Mellitus (T2DM) stand as prevalent endocrine disorders with significant impacts on global health. This study delves into the association between hypothyroidism and T2DM, unraveling their prevalence, clinical correlations, and potential implications for management.

Our findings reveal a substantial prevalence of hypothyroidism (20%) among T2DM patients at the Hind Institute of Medical Sciences, consistent with previous studies.6-8 The coexistence of these conditions prompts exploration into shared etiological factors and the bidirectional relationship between thyroid function and glucose metabolism.

This study elucidates alterations in thyroid function parameters among T2DM patients with hypothyroidism. The mean TSH level of 2.5 mIU/L indicates subclinical hypothyroidism.7 The decrease in FT4 and FT3 levels emphasizes the impact of hypothyroidism on insulin resistance and impaired glucose homeostasis.8,9

Analyses of glycemic control demonstrate higher FBG and HbA1c levels in T2DM patients with hypothyroidism. The odds ratios indicate significant correlations between hypothyroidism and age, BMI, and T2DM duration, corroborating findings from previous studies.10-12

Medication usage patterns underscore the importance of addressing hypothyroidism in T2DM management. All hypothyroid individuals are on thyroid medication, emphasizing the necessity of incorporating thyroid-specific interventions into the overall treatment plan. Statistically significant differences in medication usage reinforce the need for a tailored therapeutic approach.

The correlation analysis reveals a positive association between TSH levels and the duration of T2DM, suggesting a potential temporal relationship.13,14 This finding adds a temporal dimension to the understanding of the complex interplay between T2DM and hypothyroidism.

Understanding the association between hypothyroidism and T2DM holds clinical significance. Screening T2DM patients for thyroid dysfunction and implementing targeted interventions may optimize glycemic control. Public health strategies can benefit from recognizing the interconnected nature of these endocrine disorders to develop preventive measures.15,16

In conclusion, our study sheds valuable light on the intricate association between hypothyroidism and Type 2 Diabetes Mellitus (T2DM). The substantial prevalence of hypothyroidism among T2DM patients underscores the clinical significance of recognizing and managing these coexisting endocrine disorders. Alterations in thyroid function parameters and their impact on glycemic control emphasize the bidirectional relationship between these conditions. The observed correlations with age, BMI, and T2DM duration provide valuable insights into potential risk factors. Additionally, the medication usage patterns highlight the need for a comprehensive treatment approach tailored to address both hypothyroidism and T2DM. These findings hold implications for targeted screening strategies, optimized therapeutic interventions, and enhanced public health measures, ultimately contributing to improved outcomes for individuals affected by this complex interplay of endocrine disorders. Further research is warranted to elucidate causative mechanisms and long-term implications for patient care

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