Core health indicators in countries with high proportion of expatriates: Case study of Qatar

Background

Population size and structure have a huge impact on health indicators. In countries with a high proportion of expatriates, there are some limitations in estimating, aggregating and reporting of the health indicators, and corrections may be required in the established estimation methodologies. We review the case of Qatar to see how its specific population characteristics affect its health indicators.

Methods

We used routinely collected data and reviewed and calculated a selected list of health indicators for Qatari and non-Qatari populations residing in Qatar. Mortality and cancer incidence rates, stratified by nationality, were used for this purpose. Also, a direct method was used to estimate completeness of the death registry, compared to the mortuary data.

Results

Age and sex distribution of Qatari and non-Qatari populations are completely different. Compared to the mortuary data, completeness of death registration for the total population was estimated at 98.9 and 94.3%, with and without considering overseas deaths, respectively. Both estimates were considerably higher than estimates from the indirect methods. Mortality patterns were different even after standardization of age and stratification of sex groups; male age-standardized mortality rates were 502.7 and 242.3 per 100,000 individuals, respectively for Qataris and non-Qataris. The rates were closer in female populations (315.6 and 291.5, respectively). The leading types of cancer incidents were different in Qataris and non-Qataris.

Conclusions

Expatriates are a dynamic population with high-turnover, different from Qatari population in their age-sex structure and health status. They are more likely to be young or middle-aged and are less affected by age related diseases and cancers. Also, they might be at higher risks for specific diseases or injuries. Aggregating indicators of Qatari and non-Qatari populations might be mis-leading for policy making purposes, and common estimation correction approaches cannot alleviate the limitations. High-proportion of expatriate population also imposes significant errors to some of the key demographic estimates (such as completeness of death registry). We recommend a standardized approach to consider nationality in addition to age and sex distributions for analysis of health data in countries with a high proportion of expatriates.

Impact of high-intensity statin therapy on glycemic control post-acute coronary syndrome using real-world data

Background

Statins use has been linked with increased risk of new onset diabetes and impaired glycemic control in the JUPITER trial and meta-analyses of randomized controlled trials. Nevertheless, the evidence is scarce in the real-world clinical settings, particularly among those receiving high-intensity statin post-acute coronary syndrome (ACS).

Methods

We conducted a retrospective observational study to determine the impact of statin use post-ACS on glycosylated hemoglobin (HbA1c) and the incidence of diabetes. The study included adults admitted with ACS between January 1, 2017 and December 31, 2018 and newly started on a high-intensity statin (rosuvastatin or atorvastatin). The outcomes assessed within 12 months of statin initiation were: (a) HbA1c before and after statin use among diabetic and non-diabetic patients; (b) incidence of diabetes. Paired sample t-test was used to compare HbA1c values pre and post statin use.

Results

Of the 1,253 patients included, 627 received rosuvastatin and 626 received atorvastatin following ACS. Most of the patients were Asian (77.3%), male (95.8%) with a median age of 51 years. The baseline HbA1c was 7.2±2.2% and 45% of the study population were diabetic at baseline. Among non-diabetic patients, statin use resulted in HbA1c increase from 5.7±0.7% to 6.0±0.8%, p<0.001, while among diabetic patients who were receiving treatment for diabetes, HbA1c decreased from 8.8±1.9% to 7.8±1.9%, p<0.001. New onset diabetes occurred in 41 (6%) of the non-diabetic patients, of whom 13 (1.9%) were receiving atorvastatin, while 28 (4.1%) were on rosuvastatin, p-value = 0.032. The use of both statins resulted in a significant increase of HbA1c among non-diabetic patients as demonstrated in Figure 1.

Conclusion

High intensity statin post-ACS was associated with increased HbA1c among non-diabetic patients. In particular, rosuvastatin significantly increased the new onset of diabetes compared to atorvastatin which might provide preference of atorvastatin use over rosuvastatin among non-diabetic patients post-acute coronary syndrome.

Funding Acknowledgement

Type of funding sources: None.

Prevalence of physical activity and sedentary-related behaviors among adolescents: data from the Qatar National School Survey

OBJECTIVES

To investigate the prevalence of physical activity (PA) and sedentary behaviors among adolescents in Qatar by selected demographic characteristics.

STUDY DESIGN

Cross-sectional study.

METHODS

A total of 5862 students (2938 boys and 2924 girls) in the age group 12-17 years were included in the analyses. PA and sedentary-related measures were obtained from the self-reported survey questions.

RESULTS

Only 35.4% of students were performing 60 min of PA ≥3 days/week. The proportion of students with >2 hr screentime ranged from 43% to 57% (weekdays) and 50% to 62.5% (weekends). Girls had less odds of being physically active than the boys (odds ratio [OR] = 0.61, P < 0.001). Qatari students were less likely to be physically active than non-Qataris (OR = 0.79, P < 0.001). Age was inversely correlated with PA ([r = -0.113, P < 0.001 for participation with sports team] and [r = -0.139, P < 0.001 for school physical education classes]). Participation in sports teams positively correlated with 60 min of PA number of days in a week (r = 0.317, P < 0.001).

CONCLUSIONS

The study describes insufficient PA among youth as a public health issue of concern in the State of Qatar that requires multipronged health promotion initiatives.

The prevalence and characteristics of overweight and obesity among students in Qatar

OBJECTIVES

To estimate the prevalence of overweight and obesity using World Health Organisation (WHO) cut-offs for the body mass index (BMI) among students of the general population living in Qatar in the period 2015-2016.

STUDY DESIGN

Cross-sectional study.

METHODS

The study includes 164,963 students aged 5-19 years. The body weight and height were measured to calculate the BMI. The WHO standard cut-offs were used to categorise the BMI into severe thinness (BMI z-score <-3), thinness (BMI z-score ≥-3 to <-2), normal (BMI z-score ≥-2 to <1), overweight (BMI z-score ≥+1 to <+2) and obese (BMI z-score >+2).

RESULTS

Overweight and obesity prevalence was 44.8% and 40.4% among males and females and 45.6% and 40.9% among Qatari and non-Qatari students, respectively. Odds of obesity and overweight status were significantly higher among 10-14 and 15-19 age groups than 5-9 years age group (P < 0.001). By sex, males had 1.48 times higher odds of having obesity than females (P < 0.001), and Qatari nationals had 1.4 times higher odds of obesity than non-Qataris (P < 0.001). Although non-Qatari males also had higher odds of being overweight than females (odds ratio [OR] = 1.05, P = 0.0006), the opposite was seen among Qatari students (OR = 0.95, P = 0.01).

CONCLUSION

The result of this survey provides evidence of a high prevalence of overweight and obese students living in Qatar. Therefore, preventive strategies are essential in this population to lower the incidence of being overweight and obesity.

Detection of malignant tumors: whole-body PET with fluorine 18 alpha-methyl tyrosine versus FDG--preliminary study

PURPOSE

To compare the diagnostic potential of whole-body positron emission tomography (PET) with fluorine 18 alpha-methyl tyrosine (FMT) with that of whole-body PET with 2-[fluorine 18]fluoro-2-deoxy-D-glucose (FDG).

MATERIALS AND METHODS

Nineteen patients with or suspected of having malignant tumors and five healthy volunteers underwent whole-body PET with FMT and FDG.

RESULTS

In comparison with FDG uptake, FMT uptake was significantly less in the brain, heart, lung, liver, and spine. On a lesion-by-lesion basis, the sensitivity of whole-body FMT PET for depicting malignant tumors was inferior to that of whole-body FDG PET, but this difference was not statistically significant (74% [26 of 35 lesions] vs 91% [32 of 35 lesions], P >.05). The positive predictive value of FMT PET was superior to that of FDG PET (87% [26 of 30 lesions] vs 63% [32 of 51 lesions], P <.001). The difference in uptake between benign and malignant lesions was significant with FMT PET (mean +/- SD, 1.64 +/- 0.96 vs 0.79 +/- 0.23; P <.001) but not with FDG PET (5.02 +/- 3.56 vs 4.02 +/- 2.90, P >.05).

CONCLUSION

Whole-body FMT PET is clinically useful in the diagnosis of malignant tumors and may be effective in the depiction of primary and metastatic lesions in the cardiac region or in the brain.

A basic study on lesion detectability for hot spot imaging of positron emitters with dedicated PET and positron coincidence gamma camera

The aim of this study was to explore the correlations of detectability and the semi-quantification for hot spot imaging with positron emitters in positron emission tomography (PET) and with a positron coincidence detection system (PCD). Phantom study results for the measurement of the lesion-to-background (L/B) ratio ranged from 2.0 to 30.3, and detectability for hot spot lesion of PET and PCD were performed to correspond to clinical conditions. The detectability and semi-quantitative evaluation of hot spots from 4.4 mm to 36.9 mm in diameter were performed from the PET and PCD images. There were strong correlations between the L/B ratios derived from PET and PCD hot spot images and actual L/B ratios; but the L/B ratio derived from PET was higher than that from PCD with a significant difference of 10% to 54.8%. The detectability of hot spot imaging of PCD was lower than that of PET at 64.8% (PCD) versus 77.8% (PET). Even the actual L/B ratio was 8.0, hot spots more than 10.6 mm in diameter could be clearly identified with PCD imaging. The same identification could be achieved with PET imaging even when the actual L/B ratio was 4.0. This detailed investigation indicated that FDG PCD yielded results comparable to FDG PET on visual analysis and semi-quantitative analysis in detecting hot spots in phantoms, but semi-quantitative analysis of the L/B ratio with FDG PCD was inferior to that with FDG PET and the detectability of PCD in smaller hot spots was significantly poor.

Tumour detectability in 2-dimensional and 3-dimensional positron emission tomography using the SET-2400W: a phantom study

The purpose of this study was to investigate the detectability of small hot lesions in 2-dimensional transmission+emission (2D T/E), 2-dimensional simultaneous transmission+emission (2D simultaneous T/E) and 3-dimensional transmission+emission (3D T/E) acquisition modes in an 18F-fluorodeoxyglucose positron emission tomography (FDG PET) scan. The correlation between target detectability, target size, target to non-target uptake ratio (T/N ratio), and standardized uptake value (SUV) were studied. Small hot lesions ranging from 4.4 mm to 36.9 mm in diameter were set in a cylindrical phantom. The images of phantoms with T/N ratios of 2.0, 4.0, 6.0, 8.0, 9.6, 13.2, 17.5, 23.8 and 30.3 were obtained in 2D T/E, 2D simultaneous T/E and 3D T/E scans. Tumour uptake of 2-[18F]fluoro-2-deoxy-d-glucose (FDG) in a rabbit bearing VX-2 tumours was also studied in 2D T/E, 2D simultaneous T/E and 3D T/E scans. The target with a diameter > 10.6 mm and an actual T/N ratio from 6.0 to 30.3 could be identified on the images obtained with all the 2D T/E, 2D simultaneous T/E and 3D T/E acquisition modes. The detectability efficiency of a small hot target was found to be 77.8% in 2D T/E and 3D T/E, but 75.9% in 2D simultaneous T/E. The T/N ratio and recovery coefficient (RC) of the target from the 2D simultaneous T/E image was very similar to that from 2D T/E, and the SUV of the target from the 2D T/E image was almost the same as that from the 2D simultaneous T/E and 3D T/E images. This study indicated that 2D simultaneous T/E scanning and 3D T/E had similar abilities for detecting the tumour as did 2D T/E scanning. 2D T/E, 2D simultaneous T/E and 3D T/E scanning had the same feasibility for semi-quantitative analysis using SUV, as well as using the T/N ratios for 2D T/E and 2D simultaneous T/E. In contrast, the use of the T/N ratio in 3D T/E scanning gave an inferior result in semi-quantative analysis, although there might have been an improvement if a scatter correction had been performed.

Fundamental study of hot spot detectability in 3-dimensional positron emission tomography

The purpose of this study was to investigate the detectability of small hot lesions with the 3-dimensional transmission/emission (3D T/E) acquisition mode in FDG-PET scan. The correlation of target detectability, target size, target to non-target uptake ratio (T/N ratio) and standardized uptake value (SUV) were studied. Small hot lesions ranged from 4.4 mm to 36.9 mm in diameter were located in cylindrical phantom. The images of phantoms with a T/N ratio of 2.0, 4.0, 6.0, 8.0, 9.6, 13.2, 17.5, 23.8 and 30.3 were obtained with 2-dimensional transmission/emission (2D T/E) scan and 3D T/E scans. Targets in diameter more than 10.6 mm in diameter with an actual T/N ratio ranged from 6.0 to 30.3 could be identified on the images obtained with all the 2D T/E and 3D T/E acquisition modes. The detectability efficiency of small hot target in 2D T/E and 3D T/E scans was as same (77.8%). The T/N ratio of targets from 2D T/E images was 30% to 48.4% different to that from 3D T/E image, and the SUV of the target from the 2D T/E images was almost the same as that from 3D T/E images. This study revealed that 3D T/E scanning had similar hot spot detectability to 2D T/E scanning; 3D T/E and 2D T/E scanning had the same faculty for semiquantitative analysis using SUV. These findings may be helpful for the diagnosis and understanding of 3D T/E FDG-PET in hot lesion detection.

Biodistribution studies of the 186Re complex of 3-amino-1-hydroxypropylidene-1,1-bisphosphonic acid in mice

Preliminary studies of 186Re-labelled 3-amino-1-hydroxypropylidene-1, 1-bisphosphonic acid (APD) were performed to determine its potential for bone pain palliation, and as a treatment for increased bone resorption. The synthesis of 186Re-APD was carried out by reduction of 186Re-perrhenate in the presence of SnCl2. The APD kit, comprising 2.5 mg of APD, 2.5 mg of gentisic acid and 1 mg of Sn++ as SnCl2 2H2O, was prepared in-house. The APD was labelled with 186Re and injected intravenously into normal mice. Mice were subsequently sacrificed at 1, 3, 24, 48, 72, 168 and 240 h post-injection. The greatest accumulation of 186Re-labelled APD was found in bone, resulting in bone-to-blood ratios of 25, 35, 65, 100, 151, 181 and 189, respectively. 186Re-APD showed high uptake in bone, and relatively low uptake in soft tissue, suggesting that 186Re-APD is a potential agent for bone therapy.

Metabolic studies of [18F-alpha-methyl]tyrosine in mice bearing colorectal carcinoma LS-180

Brain and tumor uptake of [18F-alpha-methyl]tyrosine (18F-AMT) and the incorporation into each of four fractions (lipid, RNA, DNA and protein) were investigated in mice bearing LS180 colorectal carcinoma. Homogenized tissues were analyzed by the fractionation method into an acid-soluble fraction (ASF) and an acid-precipitable fraction (APF). The APF was further investigated to assess the incorporation of 18F-AMT into each fraction. Incorporation into four fractions of brain and tumor at 60 min post-injection was 20 and 12%, respectively; 10% of the activity was incorporated to lipid in brain and 5% in tumor. There was 5, 2 and 2% incorporation with RNA, DNA and protein, respectively. Metabolites in ASF were analyzed by high-performance liquid chromatography and thin-layer chromatography. There was only one radioactive peak, which corresponded to 18F-AMT. The incorporation of 18F-AMT into lipid was twice that of 18F-AMT in tumor. The uptake of 18F-AMT in tissues was rapid and accomplished before 30 min, and then slowly diffused in blood. These results implied that 18F-AMT was metabolized to protein to only a small extent and trapped as intact 18F-AMT in cells up to 60 min. We conclude that 18F-AMT is a promising tracer for tumor imaging and quantification of the transport rate using two-compartment models.

Performance stability of SHR-2000 high resolution PET for animal research

The performance of a high resolution positron emission tomography (PET) system SHR-2000 for animal studies was re-evaluated six years after its installation. The system employs a detector array consisting of BGO crystals that are 1.7 mm (transaxially) by 10 mm (axially) by 30 mm (deep). A block detector, which is a position-sensitive photomultiplier tube (PMT) coupled to 4 arrays of BGO crystals has been adopted to the system. There are 15 block detectors positioned to form a 35 cm diameter ring with a field of view (FOV) of 17 cm by 4.6 cm axially, giving the system a 7 slice imaging capability. For six year workload in spatial resolution (FWHM), there were approximately a 2.6% increase at tangential FOV and a 7.5% increase at radial FOV. In axial resolution (FWHM) there was almost no change. The count rate loss for the true count rate increased 1.3% at 200 kBq/ ml. The average slice sensitivity showed a decrease of approximately 4.1%, and in scatters it showed an increase of approximately 1.4%. In animal experiments, the bones of guinea pigs were clearly identified with 18F fluoride ion. These experiments show that after a six year workload, the system also maintains good performance and has good stability.

99mTc-labeled chimeric anti-NCA 95 antigranulocyte monoclonal antibody for bone marrow imaging

Chimeric mouse-human antigranulocyte monoclonal antibody (ch MAb) against non-specific cross-reacting antigen (NCA-95) was labeled with 99mTc (using a direct method) and 125I (using the chloramine T method), and its binding to human granulocytes and LS-180 colorectal carcinoma cells expressing carcinoembryonic antigen on their surfaces, cross-reactive with anti-NCA-95 chimeric monoclonal antibody, increased in proportion to the number of cells added and reached more than 80% and 90%, respectively. In biodistribution studies, 99mTc and 125I-labeled ch anti-NCA-95 MAb revealed high tumor uptake, and the tumor-to-blood ratio was 2.9 after 24 hours. The tumor-to-normal-organ ratio was also more than 3.0 in all organs except for the tumor-to-kidney ratio. Scintigrams of athymic nude mice confirmed the results of biodistribution studies that showed higher radioactivity in tumor and kidney of the mice administered with 99mTc-labeled ch MAb. A normal volunteer injected with 99mTc-labeled ch anti-NCA-95 antigranulocyte MAb showed clear bone marrow images, and a patient with aplastic anemia revealed irregular uptake in his lumbar spine, suggesting its utility for bone marrow scintigraphy and for the detection of hematological disorders, infections, and bone metastasis.

Biodistribution studies on L-3-[fluorine-18]fluoro-alpha-methyl tyrosine: a potential tumor-detecting agent

Iodine-123-alpha-methyl tyrosine has proven to be a promising SPECT agent for imaging amino acid uptake in tumors. We developed L-[3-(18)F]-alpha-methyl tyrosine (FMT) for PET studies. The aim of this study was to investigate its potential use as a tumor-detecting agent by using tumor-bearing mice.

METHODS

We investigated the biodistribution in normal BALB/C mice and BALB/cA nude mice bearing human rectal cancer cell line (LS180) until 120 min postinjection. FMT tumor uptake at 60 min postinjection in mice with LS180 rectal cancer, RPM11788 B-cell lymphoma and MCF7 mammary cell carcinoma was assessed, and the results were compared with 18F-fluoro-2-deoxy-D-glucose (FDG) tumor uptake. The effect of competitive inhibition of large neutral amino acid transport system using unlabeled L-alanine was also investigated.

RESULTS

The amount of FMT in blood fell to 1.05%ID/20 g at 60 min postinjection, whereas that in the pancreas was 15.2%ID/20 g, resulting in a high pancreas-to-blood ratio of 14.5. In other organs, initial uptake peaked at 5 min postinjection and then declined with time. In LS180 tumor-bearing mice, peak FMT uptake in tumor was observed at 60 min postinjection. Tumor-to-blood and tumor-to-muscle ratios ranged from 1.60 to 2.94 and from 2.79 to 3.25 over the 120-min observation period. Tumor uptake of FMT was clearly reduced by inhibition of the amino acid transport system. In mice with LS180 and MCF7 tumors, FMT tumor uptake at 60 min postinjection was significantly higher than FDG tumor uptake, whereas in RPM11788 lymphoma, uptake of FDG was significantly higher than FMT tumor uptake. Tumor-to-blood ratios of FMT in mice with LS180, RPMI1788 and MCF7 tumor at 60 min postinjection were 1.82, 5.88 and 3.56, respectively.

CONCLUSION

FMT, like other fluorinated amino acids, may become a promising tumor-detecting agent for PET, assuming that efficient methods of radiosynthesis are developed.