Apraxia Patterns for the Differentiation between Alzheimer's Disease and Frontotemporal Dementia Variants.

Background and Objectives: Despite the increasing use of biomarkers, differentiation between Alzheimer's disease (AD), behavioral variant Frontotemporal Dementia (bvFTD), and Primary Progressive Aphasia (PPA) remains a challenge. Apraxia is a supportive feature for diagnosing AD but is underrepresented in other dementia types. Herein, we investigated the presence and characteristic profiles of limb, verbal, and non-verbal apraxia in three major dementia types. Materials and Methods: Test for Upper Limb Apraxia (TULIA) and Apraxia Battery for Adults-2 (ABA-2) were administered in patients with AD (n = 22), bvFTD (n = 41), and PPA (n = 22), with 20 individuals serving as healthy controls (HC). Composite and subdomain scores were compared between each patient group and the HC. Praxis profiles indicative of each dementia type and a possible predictive value were sought. Results: Apraxia provided high diagnostic accuracy for detecting dementia compared with HC (sensitivity: 63.6-100%, specificity: 79.2-100%). Patients with AD performed worse when imitating intransitive gestures as well as pantomiming transitive gestures (mean differences: 2.10 and 3.12, respectively), compared with bvFTD. PPA patients, compared with bvFTD, had comparable results in limb, verbal, and non-verbal praxis assessments, despite the greater deterioration in the outcome. Compared with patients with AD, PPA had increased pathological outcomes in verbal (86.4% vs. 40.9%) and non-verbal apraxia (31.8% vs. 0%), while bvFTD had increased pathological outcomes in verbal apraxia (85.4% vs. 44.5%). Finally, apraxia is correlated with cognitive decline. Conclusions: Apraxia profile evaluation could contribute to the differentiation between AD and Frontotemporal Dementia (FTD). Both TULIA and ABA-2 are reliable tools that can be performed as bed-side tests in clinical practice.

Cognitive Reserve Hypothesis in Frontotemporal Dementia: Evidence from a Brain SPECT Study in a Series of Greek Frontotemporal Dementia Patients.

BACKGROUND AND OBJECTIVE: Cognitive reserve (CR) mediates the clinical expression of brain pathology in Alzheimer's disease, while there are much less relevant data in frontotemporal dementia (FTD). In the present study we examined whether CR, measured using the Cognitive Reserve Index (CRI), correlated with regional cerebral blood flow (rCBF) in Greek FTD patients. METHODS: Eighty FTD patients, i.e., 47 with behavioral variant FTD (bvFTD) and 33 with primary progressive aphasia (PPA), were enrolled into this study. CR was assessed using the CRI questionnaire, which provides a total score (CRI) and 3 subscores, i.e., CRI-education, CRI-working activity, and CRI-leisure time. The FTD-Clinical Dementia Rating Scale was used to assess the severity of dementia and a brain SPECT study was performed to measure rCBF. Finally, multiple regression analyses were conducted to explore correlations between CR indices and frontotemporal rCBF. RESULTS: In both the bvFTD and the PPA groups, higher scores in the CRI, CRI-education, and CRI-leisure time correlated with lower rCBF in the bilateral frontal and left temporal cortex, respectively, controlling for age, sex, time since symptom onset, and disease severity. CONCLUSION: In the present study, lifetime participation in leisure time activities was found to mitigate the burden of disease in bvFTD and PPA patients. Moreover, FTD patients with a higher educational attainment were able to cope better with greater brain damage. Determination of the most suitable activities to build an adequate level of CR is crucial for dementia prevention.

Frontotemporal Lobar Degeneration-Modified Clinical Dementia Rating (FTLD-CDR) Scale and Frontotemporal Dementia Rating Scale (FRS) Correlation With Regional Brain Perfusion in a Series of FTLD Patients.

Severity assessment scales for frontotemporal lobar degeneration (FTLD) have been recently introduced. In the present study, the authors examined whether the FTLD-modified Clinical Dementia Rating (FTLD-CDR) scale and the Frontotemporal Dementia Rating Scale (FRS) correlated with regional brain perfusion in Greek FTLD patients. A total of 47 behavioral variant frontotemporal dementia (bvFTD) patients and 33 primary progressive aphasia (PPA) patients were assessed for demographic data, cognitive reserve (CR), and severity of dementia and underwent brain single-photon emission computed tomography. Both scales were valid in the bvFTD group, predicting frontal lobe perfusion. In the PPA group, both scales were found to predict temporal hypoperfusion only after accounting for CR, which could imply a potential role for reserve in PPA patients.

Adaptation of the Cognitive Reserve Index Questionnaire (CRIq) for the Greek population.

Cognitive reserve (CR) is thought to reflect the cumulative brain potential derived from various cognitively demanding activities throughout the entire life. It seems to mediate both one's cognitive performance and clinical expression of different brain pathologies, such as Alzheimer's disease. Many researchers have tried to assess CR by using proxies, such as educational and occupational level, participation in leisure time activities and intelligence, alone or in various combinations. Recently, a new tool for measuring CR status was constructed, the Cognitive Reserve Index questionnaire (CRIq), comprising of all known CR proxies. CRIq also takes into account the amount of time spent during each of these activities, thus capturing the core idea behind CR theory: its active day to day formulation during all age stages. Aim of the present study was to adapt CRIq for the Greek population. The questionnaire was administered to 591 participants (age range 18-89) stratified in three age groups (young adults, middle-aged, elderly). The middle-aged group showed higher total CRI as well as CRI-Education, CRI-WorkingActivity and CRI-LeisureTime scores compared to both other groups, reflecting more years of engagement in all activities. Gender also influenced CRI scores, with men scoring higher than women, again resulting from historical and social perspectives. Overall, the CRIq showed satisfactory internal consistency, was easy to administer and its adaptation process provided solid and interpretable results. The Greek version of CRIq enriches existing dementia research methodology and allows for valid results in an ever growing field.

A multicenter evaluation of the appropriate use of single-photon emission tomography myocardial perfusion imaging in Greece.

BACKGROUND: This study evaluates the appropriate use of myocardial perfusion imaging (MPI) and determines patterns and variables associated with inappropriate testing. METHODS: Over a 10-month period data were collected prospectively from consecutive patients referred for MPI in four academic departments and an appropriate use grade was assigned (appropriate, uncertain, inappropriate, and unclassifiable scans) according to established criteria. RESULTS: Among 3,032 referrals appropriate MPI had 72.8% of patients and 19.2% of studies were inappropriate, the remaining being uncertain (7.2%) or unclassifiable (0.8%). In multivariate analysis the asymptomatic status (odds ratio 10.7, P < .001), good functional capacity (odds ratio 1.9, P < .001), an interpretable resting electrocardiogram (odds ratio 1.8, P = .004), an age <65 years (odds ratio 1.5, P = .001) and the absence of diabetes (odds ratio 1.7, P < .001) or dyslipidemia (odds ratio 1.3, P = .014) were independent predictors of inappropriate scintigraphy. The most common indication for inappropriate testing was the assessment of asymptomatic patients <2 years after percutaneous coronary intervention (PCI) (38.9%). CONCLUSIONS: The appropriate use of MPI is relatively high, but a considerable proportion of inappropriate scans is noted which is associated with markers of lower risk. The most common source of inappropriate testing is the assessment of asymptomatic patients <2 years after PCI.

Pupillometry and 123I-DaTSCAN imaging in Parkinson's disease: a comparison study.

The purpose of this study was the evaluation of pupil light reflex (PLR) in patients with Parkinson's disease (PD) by using a modern pupillometry system and the investigation of its potential relationship with dopamine transporter imaging (DaTSCAN), which is an objective method for the evaluation of presynaptic dopaminergic system. PLR was evaluated using pupillometry in 35 patients with PD without clinical evidence of autonomic dysfunction and 44 healthy matched controls. PLR was elicited using a fully automated pupillometry system and six parameters were measured. Dopamine transporter imaging was performed using radioactive ioflupane (123)I-FP-CIT [(123)I-N-ω-fluoropropyl-2ß-carbomethoxy-3ß-(4-iodophenyl)-nortropane]. A significant increase in latency and a significant decrease in amplitude, maximum constriction velocity, as well as maximum acceleration were observed in PD patients. There was no significant difference in initial radius and minimum radius values. Investigating the relationship between pupillometry parameters and (123)I-FP-CIT binding values, we correlated values from the semiquantitative analysis of radioligand uptake with pupillometry parameters, but we found no significant correlation. This study demonstrates PLR impairment in patients with PD without overt autonomic dysfunction. This impairment does not seem to correspond to the reduction of radioligand binding in the striatum as the result of presynaptic dopaminergic dysfunction, suggesting a different deterioration rate of these systems.

Imaging beyond the striatonigral dopaminergic system in Parkinson's disease.

Parkinson 's disease (PD) is characterized by progressive loss of dopaminergic neurons in the nigrostriatal pathway, but this seems to constitute only part of the whole pathological process of the disease. Accumulating data have documented the concomitant degeneration of other dopaminergic pathways and of the serotonergic, cholinergic and noradrenergic neurotransmitter systems. In addition, pathologic process is not only restricted in the brain, since the spinal cord and the peripheral autonomic nervous system are also affected. The pathogenesis of PD remains unclear. The use of positron emission tomography and single photon emission tomography may contribute to the understanding of these aspects of the disease. This review will discuss the role of PET and SPET in imaging the extrastriatal dopaminergic system and other neurotransmitter systems as well as the imaging of microglial activation and cardiac sympathetic denervation in PD. In conclusion, several PET and SPET ligands can detect changes in extrastriatal dopaminergic system as well as in the serotonergic, cholinergic and noradrenergic systems in PD and also explore its possible correlation with motor and non motor symptoms. The use of PET scintigraphy allows the detection of microglial activation in PD, while (123)I-MIBG scintigraphy depicts cardiac sympathetic denervation in PD and is a useful imaging tool for differentiating PD from other types of parkinsonism.

Somatostatin analogue scintigraphy in a patient with viral myocarditis.

Myocarditis may present clinically with a wide range of manifestations and often remains unrecognized. The diagnosis of myocarditis traditionally has been based on histological findings, but endomyocardial biopsy has a low sensitivity and clinicians are reluctant to proceed with an invasive diagnostic technique. Among newer diagnostic approaches, cardiac magnetic resonance imaging has gained acceptance as an efficient noninvasive tool to determine myocardial inflammation. In this context, imaging with radiolabeled somatostatin analogues could also be relevant because of their ability to delineate inflammatory sites. In conclusion, a case is presented in which somatostatin receptor imaging of the myocardium with (99m)Tc-depreotide tomography was used in the assessment of viral myocarditis.

A chemical model suggesting the maximum radiolabeled somatostatin analogue tumor uptake, in the presence of unlabeled somatostatin.

Somatostatin analogues (SSA), both radiolabeled and unlabeled play an important role in the management of carcinoid tumors. They are often administered in parallel, the unlabeled analogue for treating the carcinoid tumors' symptoms and the radiolabeled one for imaging tumors foci. There is a debate about when is the optimum time for a somatostatin receptor scintigraphy during treatment. Opinions are divided, with some authors suggesting stopping SSA treatment, while others do not. Our aim was to try to explore pharmacokinetics behind the radiolabeled peptide administration in the presence of circulating in blood unlabeled SSA, by using a model of "law of mass". Applying the pharmacokinetic data from the manufacturers' Prescription Information Sheet in a formula describing competitive binding, led to a reduced uptake for the radiolabeled peptide in the presence of the unlabeled peptide, in comparison with standalone radiolabeled peptide administration, regardless of the total number of available receptors. We provide data that unlabeled somatostatin should be withdrawn for no less than 14 days before the labeled SSA is administered, because biotherapy agents interfere with both diagnostic and therepeutic nuclear medicine procedures. Further research is needed to reach secure conclusions on patient medication management before diagnostic scans or therapeutic administrations in nuclear medicine. In conclusion, by waiting at least 6 half-lives (14 days), after the unlabeled SSA administration, the radiolabeled receptor uptake increased two-fold to three-fold, as compared to simultaneous administration of radiolabeled and unlabeled peptides depending on which SSA was used.

Preliminary validation of the apraxia battery for adults-second edition (ABA-2) in Greek patients with dementia.

BACKGROUND: Apraxia is considered a supportive feature in Alzheimer's disease (AD) patients. It has been reported that patients with frontotemporal dementia (FTD) may present apraxia, especially in the buccofacial area. The Apraxia Battery for Adults (ABA-2) is a brief and practical battery for praxis impairment and has been validated in Greek post-stroke patients. AIM: To validate and evaluate ABA-2 test, translated and culturally adapted, in a sample of Greek demented patients. PATIENTS AND METHODS: Patients diagnosed with FTD (n = 20) and AD (n = 20) were included in the study. Age-, gender-, and education- matched healthy controls (n = 20) were also tested. All participants completed Adenbrooke's Cognitive Examination-Revised (ACE-R), Frontal Rating Scale (FRS), Frontal Behavioral Inventory (FBI), and ABA-2 battery. Sensitivity and specificity of ABA-2 were calculated, as well as its consistency and statistical significance for diagnosing apraxia. RESULTS: The ABA-2 was able to differentiate demented patients from healthy controls with a sensitivity of 77.5% and specificity of 95%. Its validity was confirmed with Cronbach's alpha coefficient > 0.7, indicating satisfactory internal reliability. Statistically significant differences were found when comparing total ABA-2 score (p < 0.0001), as well as 3 out of 6 subtests of ABA-2, between the two study groups. Age, gender and education were not correlated with ABA-2 score. CONCLUSION: ABA-2 is a valid, reliable and sensitive battery to differentiate demented patients from healthy individuals in the Greek population. We propose the modification of ABA-2 to a 5-subtest tool, to be administered as a bed-side test.

The effect of vitamin D supplementation on glycemic status of elderly people with prediabetes: a 12-month open-label, randomized-controlled study.

BACKGROUND: Data on the efficacy of vitamin D in improving the glycemic status of elderly people with prediabetes are scarce. This open-label, randomized-controlled trial investigated the effect of vitamin D supplementation on glycemic markers of Greek people with prediabetes aged 60 years or above, over 12 months. RESEARCH DESIGN AND METHODS: Participants were randomized to a weekly vitamin D3 dose of 25,000 IU (n = 45) or nothing (n = 45), on top of lifestyle measures. Anthropometric and glycemic markers were assessed at baseline, 3, 6, and 12 months. RESULTS: Supplemented participants demonstrated a significant increase in 25(OH)D concentrations at 3,      6,      and 12 months     compared to baseline    . In the intervention group, fasting glucose was decreased at 6 months compared to baseline (96.12 ± 5.51 vs 103.40 ± 12.05 mg/dl, p < 0.01) and glycated hemoglobin was significantly lower at 6 and 12 months compared to baseline [5.82 ± 0.21% vs 5.87 ± 0.21%, p = 0.004 and 5.80 ± 0.23% vs 5.87 ± 0.21%, p < 0.001, respectively]. CONCLUSIONS: Vitamin D could be complementary to lifestyle change strategy for the management of prediabetes in the elderly. CLINICAL TRIAL REGISTRATION: ISRCTN51643592.

Vitamin D Alleviates Anxiety and Depression in Elderly People with Prediabetes: A Randomized Controlled Study.

Older people are prone to frailness, present poor adherence to pharmacotherapy, and often have adverse drug effects. Therefore, it is important to develop effective and safe interventions to mitigate the burden of anxiety and depression disorders in this population. The aim of this study was to investigate the effect of vitamin D supplementation on the anxiety and depression status of elderly people with prediabetes. Participants were randomly assigned a weekly dose of vitamin D3 of 25,000 IU (n = 45, mean age 73.10 ± 7.16 years) or nothing (n = 45, mean age 74.03 ± 7.64 years), in addition to suggested lifestyle measures. The State-Trait Anxiety Inventory subscales (STAI-T and STAI-S) and the Patient Health Questionnaire-9 (PHQ-9) were used to evaluate anxiety and depression levels, respectively, at baseline, 6, and 12 months. A total of 92.68% of the participants in the vitamin D group and 97.14% of the controls exhibited vitamin D deficiency (<20 ng/mL) at baseline. Mean STAI-T scores were lower in supplemented individuals than in the control group at 6 (38.02 ± 9.03 vs. 43.91 ± 7.18, p = 0.003) and 12 months (32.35 ± 7.77 vs. 44.97 ± 7.78, p < 0.001). The same pattern was evident for STAI-S scores at 6 (37.11 ± 7.88 vs. 43.20 ± 9.33, p = 0.003) and 12 months (32.59 ± 6.45 vs. 44.60 ± 9.53, p < 0.001). Supplemented participants demonstrated lower mean PHQ-9 scores compared to controls at 6 (15.69 ± 6.15 vs. 19.77 ± 8.96, p = 0.021) and 12 months (13.52 ± 5.01 vs. 20.20 ± 8.67, p < 0.001). Participants with deficiency and insufficiency at baseline experienced equal benefits of supplementation in terms of anxiety and depression scores. In conclusion, in a high-risk population, a weekly vitamin D supplementation scheme was effective in alleviating anxiety and depression symptoms. More studies are needed to elucidate the relevant mechanisms.

Somatostatin receptor imaging with (111)In-pentetreotide in gastro-intestinal tract and lung neuroendocrine tumors-Impact on targeted treatment.

Somatostatin is a neuropeptide that confers a wide range of pharmacological properties. Indium-111-tagged pentetreotide ((111)In-P) is a radiolabeled analogue of somatostatin indicated for the in vivo scintigraphic localization of neuroendocrine tumors (NET). In cases of NET of the gastro-intestinal tract we describe the sensitivity compared to conventional anatomical imaging modalities and especially the possibility that (111)In-P may change therapeutic management into up one fourth of the patients. In cases of small cell lung carcinoma it has been used for the evaluation of somatostatin receptor status and a substantial tool for differentiation between limited and extensive disease, especially when combined with anatomical imaging methods. We also describe the radiolabeled with yttrium-90 or lutetium-177 somatostatin analogue peptides in the treatment of NET and also the use of (111)In-P for the selection of patients for targeted treatment.

Cinacalcet in hyperparathyroidism secondary to X-linked hypophosphatemic rickets: case report and brief literature review.

X-linked dominant hypophosphatemic rickets (XLH) is the most prevalent genetic form of hypophosphatemic rickets. Standard treatment of XLH patients includes long-term administration of phosphate and calcitriol. Treated patients usually respond well to the conventional therapy and demonstrate amelioration of rachitic symptoms and improved growth. However, long-term administration of phosphate and vitamin D preparations is sometimes complicated with nephrocalcinosis, secondary or tertiary hyperparathyroidism and arterial hypertension. We describe a patient with XLH, caused by a rare missense mutation of the PHEX gene. The patient, while under treatment with alphacalcidol and oral phosphate, developed hypercalciuria, nephrocalcinosis, secondary hyperparathyroidism and arterial hypertension. Cinacalcet was added to the therapeutic regimen and the long-term effects on calciotropic parameters and FGF23 levels are herein reported.

[Molecular imaging of cerebral blood flow and metabolism with SPET and PET in principal dementias].

In this review article the significance of molecular imaging techniques, single photon emission tomography and positron emission tomography (SPET and PET), in the diagnosis and differential diagnosis of various types of dementia is described. A major part of this article is focused on molecular imaging in Alzheimer's disease where parietal, temporal and posterior cingulate cortex hypoperfusion and hypometabolism are the predominant findings in molecular imaging modalities. In cases of mild amnestic cognitive impairment, molecular SPET imaging can differentiate patients converting to Alzheimer's disease from non converters. Molecular SPET imaging with pre-synaptic dopamine receptors radioligand ((123)I-ioflupane or DaTSCAN), is the method of choice in order to differentiate Alzheimer's disease from Lewy body dementia. Finally, nuclear medicine procedures support the diagnosis in fronto-temporal and multi-infarct dementia.

(123)I-FP-CIT SPET striatal uptake in parkinsonian patients with the alpha-synuclein (G209A) mutation A.

Autosomal dominant familial Parkinson's disease (PD) due to the alpha-synuclein (G209A) mutation shares similar clinical characteristics with sporadic PD. Pathological studies however indicate more widespread neuronal degeneration in the familial form. We performed (123)I-FP-CIT SPET (DaTSCAN) study in nine patients with familial PD carrying the alpha-synuclein (G209A) mutation and fifteen matched patients with sporadic disease. Both groups had equal radioligand reduction uptake in the striatum but the alpha-synuclein patients showed less asymmetry and increased putamen to caudate ratio. Our findings indicate that there are minor differences in DAT SPET parameters between alpha-synuclein and sporadic PD patients insufficient to provide differential diagnosis.

Unexpected dose to the daughter of a patient treated with iodine-131 for hyperthyroidism.

Patients treated with radioiodine for thyrotoxicosis and hyperthyroidism are a source of radiation exposure and represent a potential radiation hazard for the people in their environment. Doses to the relatives can be estimated from dose rates of the patient or measured with a proper dosimeter. Sensitive thermoluminescent dosimeters have been used to measure the doses absorbed by the family members of patients treated with iodine-131 ((131)I) for thyrotoxicosis. In the present case, a 12 year old daughter of a female patient, aged 41 years, treated with 592 MBq of (131)I, received a dose of 7.79 mSv during the first seven days. This value is well above the dose constraints proposed by the International Commission on Radiological Protection, i.e 1 mSv for children and fetuses and 3 mSv for carers. Obviously, the patient and her daughter didn't follow the given restrictions. That was unexpected for a 12 year old child who didn't need special care and was able to understand and follow certain instructions. It is the opinion of the authors that if there are children in the family of a hyperthyroid patient treated with (131)I, they should stay in another house for at least a week. If this is impossible for social reasons, hospitalization of the patient should be considered, although treatment of thyrotoxicosis is held in an out-patient basis.

[Indium-111-DTPA-phenyl-pentetreotide somatostatin receptors' scintigraphy in the evaluation of patients with suspected gastro-entero-pancreatic tumors. Comparison with computerized tomography].

Gastro-entero-pancreatic tumors (GEP) contain, in their majority, somatostatin receptors. In-111-DTPA-phenyl-pentetreotide has been proved to have high affinity for somatostatin receptors subtypes 2, 3 and 5. The aim of the present study was to evaluate the utility of (111)In-DTPA-O somatostatin receptors' scintigraphy (SRS) in the diagnosis of suspected GEP. Thirty-five consecutive patients (17 males and 18 females-mean age 57.9+/-7.6) with GEP as a possible diagnosis were enrolled in the study. The primary diagnosis was diarrheic syndrome susceptive of intestinal carcinoid tumor (24 patients), carcinoid of the rectum (2 patients), adenocarcinoma of the pancreas (2 patients), insulinoma (2 patients), gastrinoma (3 patients) and hepatocellular carcinoma (2 patients). All patients were submitted to computerized tomography (CT) of the thorax and the abdomen and pentetreotide SRS was performed 4 h (total body and SPET acquisition) and 24 h (planar views), post iv injection of 185 MBq of the radiolabeled compound. Results showed: Four of the patients were false positive diagnosed as having inflammatory intestinal disease and gallbladder dilatation. At the time of the evaluation, 14 of the remaining patients were free of disease, concerning secondary involvement. In these cases, CT and SRS studies matched each other, with no pathological lesions and no abnormal accumulation of the radiopharmaceutical respectively. Concerning pathological cases, only one SRS study in a patient with rectum carcinoid was normal, with liver lesions in the CT study. These lesions were considered as subtypes 2, 3 and 5 somatostatin receptors negative. SRS revealed three lesions more than CT. According to these results, sensitivity of SRS study was 93.8% and specificity 86.9%. The authors believe that molecular imaging of somatostatin receptors, is a sensitive method for the evaluation of patients with GEP tumors. However, in cases of intestinal disease, we should be aware of false positive results due to inflammatory processes and the presence of lymphocyte infiltration.

Molecular imaging (SPECT and PET) in the evaluation of patients with movement disorders.

In this article the role of molecular imaging with SPECT and PET in patients with movement disorders is reviewed. It is mentioned that SPECT and PET imaging with cocaine analogues ((123)I-beta-CIT,(123)I-FP-CIT, (18)F-DOPA), radioligands labeling the presynaptic dopamine transporters, is of value for the differentiation of patients with PD or Parkinson-plus syndromes with individuals with essential tremor. In addition the clinical impact of this procedure, the role of molecular imaging in the preclinical diagnosis and in the follow-up of patients with PD, as well as, in the differential diagnosis between Alzheimer's disease and Lewy-body dementia, is evaluated. Finally, the clinical impact of (123)I-IBZM-SPECT imaging, a radiopharmaceutical which labels the postsynaptic D(2) receptors and the discrimination between idiopathic PD and Parkinson-plus syndromes (multiple system atrophy, progressive supranuclear palsy and corticobasal ganglia degeneration), is mentioned.

Thyroid Autoimmunity in the Context of Type 2 Diabetes Mellitus: Implications for Vitamin D.

Vitamin D deficiency has been associated with both type 2 diabetes mellitus (T2DM) and autoimmune disorders. The association of vitamin D with T2DM and thyroid autoimmunity (TAI) has not been investigated. Thus, we aimed to explore the putative association between T2DM and thyroid autoimmunity (TAI) focusing on the role of 25-hydroxy-vitamin D (25(OH)D). Study population included 264 T2DM patients and 234 controls. To explore the potential association between 25(OH)D and thyroid autoimmunity while controlling for potential confounders-namely, age, gender, body mass index, and presence of T2DM-multivariate logistic regression analyses were undertaken. Patients with T2DM were younger (P < 0.001) and had significantly lower 25(OH)D levels (P < 0.001) and higher anti-TPO titers (P = 0.005). Multivariable logistic regression analyses suggested that T2DM and 25(OH)D levels were significantly associated with the presence of thyroid autoimmunity. In an elderly population of diabetic patients and controls with a high prevalence of vitamin D deficiency/insufficiency, a patient with T2DM was found to be 2.5 times more likely to have thyroid autoimmunity compared to a nondiabetic individual and the higher the serum 25(OH)D levels were, the higher this chance was.