Association between body mass index (BMI) and [123I]Ioflupane (DaTSCAN) availabilities in patients with parkinsonism using single-photon emission computed tomography-computed tomography (SPECT-CT)

Puja Parekh; Patrick Begley; Maryam Jessop; Mark Aplin; Elena Missir; Helena McMeekin; Gosia Raczek; Nitasha Singh; Sabina Dizdarevic

doi:10.1186/s41824-023-00181-6

Association between body mass index (BMI) and [¹²³I]Ioflupane (DaTSCAN) availabilities in patients with parkinsonism using single-photon emission computed tomography-computed tomography (SPECT-CT)

Eur J Hybrid Imaging. 2023 Nov 20;7(1):21. doi: 10.1186/s41824-023-00181-6.

Authors

Affiliations

¹ Brighton and Sussex Medical School, Brighton, England.
² Nuclear Medicine Department, Royal Sussex County Hospital, University Hospitals Sussex NHS Foundation Trust, Brighton, England.
³ Hermes Medical Solutions, London, England.
⁴ Clinical Imaging Science Centre, Neuroscience and Medicine, Brighton and Sussex Medical School, Brighton, England. sabina.dizdarevic@nhs.net.
⁵ Brighton and Sussex Medical School, Brighton, England. sabina.dizdarevic@nhs.net.
⁶ Nuclear Medicine Department, Royal Sussex County Hospital, University Hospitals Sussex NHS Foundation Trust, Brighton, England. sabina.dizdarevic@nhs.net.

Abstract

Aim: [¹²³I]Ioflupane (DaTSCAN) has a high binding affinity to the dopamine (DA) transporter (DaT) and tenfold less affinity to serotonin (5-HT) transporter (SERT). Both neurotransmitters are considered to contribute to body weight regulation. This study assesses the association between body mass index (BMI) and DaTSCAN availability in brain.

Method: Scans from 74 consecutive patients who had undergone DaTSCAN single-photon emission computed tomography-computed tomography (SPECT-CT) were used to obtain semi- and absolute quantitative data in several volumes of interest (VOIs). Relative semi-quantitative specific binding ratios (SBRs) from Chang attenuated SPECT were obtained from GE DaTQUANT. Absolute normalised concentration (NC) was calculated from attenuation/scatter corrected SPECT-CT images, using an adapted version of the EARL Ltd (European Association of Nuclear Medicine (EANM) Research 4 Life) template. Scans were subdivided into either degenerative parkinsonism (abnormal = 49), borderline (n = 14) or scan without evidence of dopaminergic deficit (SWEDD = 11) using visual assessment and SBR values by two nuclear medicine consultants.

Results: SBRs did not correlate with BMI. However, NC values correlated negatively in the entire cohort, with the strongest correlation in the frontal (r = - 0.649. p = 0.000), occipital (r = - 0.555, p = 0.000) regions and pons (r = - 0.555, p = 0.000). In the abnormal (n = 49) and SWEDD group (n = 11), NC of the frontal region was the most correlated with BMI (r = - 0.570, p = 0.000; r = - 0.813, p = 0.002, respectively). In the borderline group (n = 14), the left posterior putamen displayed the strongest correlation (r = - 0.765, p = 0.001).

Conclusion: Absolute NC values demonstrate a strong inverse correlation with BMI, strongest in the extrastriatal regions. Due to the predominately non-overlapping distribution of DaT and SERT, this study suggests greater involvement of SERT in obesity with possible interplay with DA transmission.

Keywords: BMI; DaTQUANT; DaTSCAN; Obesity; Specific binding ratios.