Residents at high altitude show a lower glucose profile than sea-level residents throughout 12-hour blood continuous monitoring

A narrative review of periodic breathing during sleep at high altitude: From acclimatizing lowlanders to adapted highlanders

Periodic breathing during sleep at high altitude is almost universal among sojourners. Here, in the context of acclimatization and adaptation, we provide a contemporary review on periodic breathing at high altitude, and explore whether this is an adaptive or maladaptive process. The mechanism(s), prevalence and role of periodic breathing in acclimatized lowlanders at high altitude are contrasted with the available data from adapted indigenous populations (e.g. Andean and Tibetan highlanders). It is concluded that (1) periodic breathing persists with acclimatization in lowlanders and the severity is proportional to sleeping altitude; (2) periodic breathing does not seem to coalesce with poor sleep quality such that, with acclimatization, there appears to be a lengthening of cycle length and minimal impact on the average sleeping oxygen saturation; and (3) high altitude adapted highlanders appear to demonstrate a blunting of periodic breathing, compared to lowlanders, comprising a feature that withstands the negative influences of chronic mountain sickness. These observations indicate that periodic breathing persists with high altitude acclimatization with no obvious negative consequences; however, periodic breathing is attenuated with high altitude adaptation and therefore potentially reflects an adaptive trait to this environment.

Intermittent normobaric hypoxia alters substrate partitioning and muscle oxygenation in individuals with obesity: implications for fat burning

This single-blind, crossover study aimed to measure and evaluate the short-term metabolic responses to continuous and intermittent hypoxic patterns in individuals with obesity. Indirect calorimetry was used to quantify changes in resting metabolic rate (RMR), carbohydrate (CHOox, %CHO), and fat oxidation (FATox, %FAT) in nine individuals with obesity pre and post: 1) breathing normoxic air [normoxic sham control (NS-control)], 2) breathing continuous hypoxia (CH), or 3) breathing intermittent hypoxia (IH). A mean peripheral oxygen saturation ([Formula: see text]) of 80-85% was achieved over a total of 45 min of hypoxia. Throughout each intervention, pulmonary gas exchanges, oxygen consumption (V̇o2) carbon dioxide production (V̇co2), and deoxyhemoglobin concentration (Δ[HHb]) in the vastus lateralis were measured. Both RMR and CHOox measured pre- and postinterventions were unchanged following each treatment: NS-control, CH, or IH (all P > 0.05). Conversely, a significant increase in FATox was evident between pre- and post-IH (+44%, P = 0.048). Although the mean Δ[HHb] values significantly increased during both IH and CH (P < 0.05), the greatest zenith of Δ[HHb] was achieved in IH compared with CH (P = 0.002). Furthermore, there was a positive correlation between Δ[HHb] and the shift in FATox measured pre- and postintervention. It is suggested that during IH, the increased bouts of muscle hypoxia, revealed by elevated Δ[HHb], coupled with cyclic periods of excess posthypoxia oxygen consumption (EPHOC, inherent to the intermittent pattern) played a significant role in driving the increase in FATox post-IH.

Moderate altitude exposure impacts host fasting blood glucose and serum metabolome by regulation of the intestinal flora

Moderate altitude exposure has shown beneficial effects on diabetes incidence but the underlying mechanisms are not understood. Our study aimed to investigate how the human gut microbiome impacted the serum metabolome and associated with glucose homeostasis in healthy Chinese individuals upon moderate-altitude exposure. Faecal microbiome composition was assessed using shotgun metagenomic sequencing. Serum metabolome was acquired by untargeted metabolomics technology, and amino acids (AAs) and propionic acid in serum were quantified by targeted metabolomics technology. The results indicated that the moderate-altitude exposed individuals presented lowered fasting blood glucose (FBG) and propionic acid, increased circulating L-Glutamine but decreased L-Glutamate and L-Valine, which correlated with enriched Bacteroidetes and decreased Proteobacteria. Additionally, the silico causality associations among gut microbiota, serum metabolome and host FBG were analyzed by mediation analysis. It showed that increased Bacteroides ovatus (B. ovatus) and decreased Escherichia coli (E. coli) were identified as the main antagonistic species driving the association between L-Glutamate and FBG in silico causality. Furthermore, the high-fat diet (HFD) fed mice subjected to faecal microbiota transplantation (FMT) were applied to validate the cause-in-fact effects of gut microbiota on the beneficial glucose response. We found that microbiome in the moderate-altitude exposed donor could predict the extent of the FBG response in recipient mice, which showed lowered FBG, L-Glutamate and Firmicutes/Bacteroidetes ratio. Our findings suggest that moderate-altitude exposure targeting gut microbiota and circulating metabolome, may pave novel avenues to counter dysglycemia.

Association between VDR genetic polymorphisms and risk of gestational diabetes mellitus in the Chinese population

BACKGROUND AND AIMS

Abnormal metabolism of vitamin D was the primary mechanism in many pregnancy diseases. Our study was the first to examine the hypothesis that VDR gene polymorphisms contribute to the risk of gestational diabetes mellitus (GDM) in the Chinese population at high altitudes.

MATERIALS AND METHODS

One hundred and eighteen women with GDM and 104 women with normal glucose tolerance (NGT) were included in this study using a case-control design. Four single nucleotide polymorphisms (g.47879112G > A, g.47846052C > T, g.47844974A > G, and g.47845054C > A) of mother and fetus were genotyped.

RESULTS

Maternal and fetal frequency of the A allele of g.47879112G > A was significantly increased in women with GDM than in those with NGT (p < .05). A correlation between the AA homozygous genotype of g.47879112G > A and GDM was noted. Compared with non-carriers, A allele carriers showed higher fasting plasma insulin and two-hour post-challenge plasma glucose (2h-PPG), and lower levels of vitamin D. Furthermore, both maternal and fetal 4-marker haplotype ACCG were found to be significantly associated with GDM (p < .05).

CONCLUSIONS

Association and haplotype analysis indicated that the A allele of g.47879112G > A could be a risk factor for GDM development in the Chinese population at high altitudes. Additionally, the VDR gene polymorphism of the fetus and mother may have a synergistic effect. The VDR polymorphism is associated with an increased risk of GDM and may be useful for predicting the development of the disease.

Organ-specific fuel rewiring in acute and chronic hypoxia redistributes glucose and fatty acid metabolism

Oxygen deprivation can be detrimental. However, chronic hypoxia is also associated with decreased incidence of metabolic syndrome and cardiovascular disease in high-altitude populations. Previously, hypoxic fuel rewiring has primarily been studied in immortalized cells. Here, we describe how systemic hypoxia rewires fuel metabolism to optimize whole-body adaptation. Acclimatization to hypoxia coincided with dramatically lower blood glucose and adiposity. Using in vivo fuel uptake and flux measurements, we found that organs partitioned fuels differently during hypoxia adaption. Acutely, most organs increased glucose uptake and suppressed aerobic glucose oxidation, consistent with previous in vitro investigations. In contrast, brown adipose tissue and skeletal muscle became "glucose savers," suppressing glucose uptake by 3-5-fold. Interestingly, chronic hypoxia produced distinct patterns: the heart relied increasingly on glucose oxidation, and unexpectedly, the brain, kidney, and liver increased fatty acid uptake and oxidation. Hypoxia-induced metabolic plasticity carries therapeutic implications for chronic metabolic diseases and acute hypoxic injuries.

Type 2 diabetes mellitus in Peru: A literature review including studies at high-altitude settings

We performed a comprehensive review of recent publications about type 2 diabetes mellitus (T2DM) in Peru, including studies among people living at high altitude above the sea level. An increase in the prevalence of T2DM in Peru has been reported, the reasons are multifactorial and coinciding with the strong economic growth that our country has experienced over the last 20 years along with migration from the Andean regions to the coast and the adoption of a lifestyle that is a known to be a risk factor for obesity and insulin resistance. Scarce information is available in Peru about the prevalence of chronic complications of T2DM such as retinopathy, neuropathy, and nephropathy. There is a need for a health care plan based on early diagnosis of T2DM to reduce social and economic problems, as recommended by the WHO and the United Nations.

Oxygen in Metabolic Dysfunction and Its Therapeutic Relevance

Significance: In recent years, a number of studies have shown altered oxygen partial pressure at a tissue level in metabolic disorders, and some researchers have considered oxygen to be a (macro) nutrient. Oxygen availability may be compromised in obesity and several other metabolism-related pathological conditions, including sleep apnea-hypopnea syndrome, the metabolic syndrome (which is a set of conditions), type 2 diabetes, cardiovascular disease, and cancer. Recent Advances: Strategies designed to reduce adiposity and its accompanying disorders have been mainly centered on nutritional interventions and physical activity programs. However, novel therapies are needed since these approaches have not been sufficient to counteract the worldwide increasing rates of metabolic disorders. In this regard, intermittent hypoxia training and hyperoxia could be potential treatments through oxygen-related adaptations. Moreover, living at a high altitude may have a protective effect against the development of abnormal metabolic conditions. In addition, oxygen delivery systems may be of therapeutic value for supplying the tissue-specific oxygen requirements. Critical Issues: Precise in vivo methods to measure oxygenation are vital to disentangle some of the controversies related to this research area. Further, it is evident that there is a growing need for novel in vitro models to study the potential pathways involved in metabolic dysfunction to find appropriate therapeutic targets. Future Directions: Based on the existing evidence, it is suggested that oxygen availability has a key role in obesity and its related comorbidities. Oxygen should be considered in relation to potential therapeutic strategies in the treatment and prevention of metabolic disorders. Antioxid. Redox Signal. 35, 642-687.

Diabetes increases the risk of COVID-19 in an altitude dependent manner: An analysis of 1,280,806 Mexican patients

AIMS

The objective of this study is to analyze how the impact of Diabetes Mellitus [DM] in patients with COVID-19 varies according to altitudinal gradient.

METHODS

We obtained 1,280,806 records from adult patients with COVID-19 and DM to analyze the probability of COVID-19, development of COVID-19 pneumonia, hospitalization, intubation, admission to the Intensive Care Unit [ICU] and case-fatality rates [CFR]. Variables were controlled by age, sex and altitude of residence to calculate adjusted prevalence and prevalence ratios.

RESULTS

Patients with DM had a 21.8% higher prevalence of COVID-19 and an additional 120.2% higher prevalence of COVID-19 pneumonia. The adjusted prevalence was also higher for these outcomes as well as for hospitalization, intubation and ICU admission. COVID-19 and pneumonia patients with DM had a 97.0% and 19.4% higher CFR, respectively. With increasing altitudes, the probability of being a confirmed COVID-19 case and the development of pneumonia decreased along CFR for patients with and without DM. However, COVID-19 patients with DM were more likely to require intubation when residing at high altitude.

CONCLUSIONS

The study suggests that patients with DM have a higher probability of being a confirmed COVID-19 case and developing pneumonia. Higher altitude had a protective relationship against SARS-CoV-2 infection; however, it may be associated with more severe cases in patients with and without DM. High altitude decreases CFR for all COVID-19 patients. Our work also shows that women are less affected than men regardless of altitude.

Prevalence of non-communicable diseases risk factors and their determinants: Results from STEPS survey 2019, Nepal

Background

The World Health Organization (WHO) recommends ongoing surveillance of non-communicable diseases (NCDs) and their risk factors, using the WHO STEPwise approach to surveillance (STEPS). The aim of this study was to assess the distribution and determinants of NCD risk factors in Nepal, a low-income country, in which two-thirds (66%) of annual deaths are attributable to NCDs.

Methods

A nationally representative NCD risk factors STEPS survey (instrument version 3.2), was conducted between February and May 2019, among 6,475 eligible participants of age 15–69 years sampled from all 7 provinces through multistage sampling process. Data collection involved assessment of behavioral and biochemical risk factors. Complex survey analysis was completed in STATA 15, along with Poisson regression modelling to examine associations between covariates and risk factor prevalence.

Results

The most prevalent risk factor was consumption of less than five servings of fruit and vegetables a day (97%; 95% CI: 94.3–98.0). Out of total participants, 17% (95% CI: 15.1–19.1) were current smoker, 6.8% (95% CI: 5.3–8.2) were consuming ≥60g/month alcohol per month and 7.4% (95% CI:5.7–10.1) were having low level of physical activity. Approximately, 24.3% (95% CI: 21.6–27.2) were overweight or obese (BMI≥25kg/m²) while 24.5% (95% CI: 22.4–26.7) and 5.8% (95% CI: 4.3–7.3) had raised blood pressure (BP) and raised blood glucose respectively. Similarly, the prevalence of raised total cholesterol was 11% (95% CI: 9.6–12.6). Sex and education level of participants were statistically associated with smoking, harmful alcohol use and raised BP. Participants of age 30–44 years and 45–69 years were found to have increased risk of overweight, raised BP, raised blood sugar and raised blood cholesterol. Similarly, participants in richest wealth quintile had higher odds of insufficient physical inactivity, overweight and raised blood cholesterol. On average, each participant had 2 NCD related risk factors (2.04, 95% CI: 2.02–2.08).

Conclusion

A large portion of the Nepalese population are living with a variety of NCD risk factors. These surveillance data should be used to support and monitor province specific NCD prevention and control interventions throughout Nepal, supported by a multi-sectoral national coordination mechanism.

Prevalence of diabetes and prediabetes in tribal population of Kashmir: Lessons for the future

AIMS

Considering a surge in the incidence of Diabetes mellitus (DM) across all ethnic groups and lack of any representative data from the tribal communities of Jammu and Kashmir, the present study aimed to assess the prevalence of DM and prediabetes in them.

METHODS

Subjects were recruited from five districts of Kashmir valley using multistage cluster sampling by probability proportional to size (PPS) technique. Data collection included recording of socio-demographic, medical facts, assessment of anthropometric parameters and biochemical evaluation HbA1c and random blood glucose measurements as per the American Diabetes Association (ADA) criteria were used for diagnosis of DM.

RESULTS

A total of 6808 subjects were recruited in this study including 2872 (42%) men and 3936 (58%) women with mean age of 39.60 ± 20.19 years and 35.17 ± 16.70 years, respectively. Around 8.60% subjects were obese, 38.9% were found to be hypertensive, 73% had dyslipidemia and 3.75% had metabolic syndrome. About 1.26% (0.5% males and 0.9% females) had DM and 11.64% had prediabetes based on HbA1c cut offs. Increasing age, body mass index and family history portend significant risk factors while smoking and sedentary lifestyle increased the risk marginally.

CONCLUSIONS

Although the prevalence of DM among tribals of Kashmir valley is lower than general population, the higher prediabetes to DM ratio may indicate a future trend of increasing DM prevalence in this disadvantageous subpopulation.

Epidemiological Features of Glycemic Levels and Relative Determinants at Different Altitudes Among Tibetans in China: A Cross-Sectional Population-Based Study

Risk factors associated with diabetes mellitus have been widely researched worldwide, but the determinants of glycemic levels among Tibetans in China are currently unclear. We thus aimed to determine the relationship between altitude and glycemic levels and to identify factors associated with glycemic levels among Tibetans in China. In 2011, a total of 1,659 Tibetans (aged ≥18 years) from Changdu, China, were enrolled to this cross-sectional research. Potential factors associated with postprandial glucose (PPG), fasting plasma glucose (FPG), and insulin (INS) levels were assessed. FPG and PPG levels increased with age and total cholesterol (TC) level. In addition, FPG levels were higher among patients with rural residence and hypertension, while PPG levels increased with increasing BMI. INS levels increased with residence, lower education, higher BMI, and higher TG levels and decreased with higher altitude and TC levels. Moreover, risk factors for FPG, PPG, and INS differed in those residing at a higher altitude. These findings identify several important risk factors that affect glycemic levels and may be used to develop effective strategies for metabolic disease prevention among populations in high-altitude areas. Furthermore, these findings suggest that it is necessary to formulate a standard for PPG, FPG, and INS in high-altitude areas.

Oxygenation of adipose tissue: A human perspective

Obesity is a complex disorder of excessive adiposity, and is associated with adverse health effects such as cardiometabolic complications, which are to a large extent attributable to dysfunctional white adipose tissue. Adipose tissue dysfunction is characterized by adipocyte hypertrophy, impaired adipokine secretion, a chronic low‐grade inflammatory status, hormonal resistance and altered metabolic responses, together contributing to insulin resistance and related chronic diseases. Adipose tissue hypoxia, defined as a relative oxygen deficit, in obesity has been proposed as a potential contributor to adipose tissue dysfunction, but studies in humans have yielded conflicting results. Here, we will review the role of adipose tissue oxygenation in the pathophysiology of obesity‐related complications, with a specific focus on human studies. We will provide an overview of the determinants of adipose tissue oxygenation, as well as the role of adipose tissue oxygenation in glucose homeostasis, lipid metabolism and inflammation. Finally, we will discuss the putative effects of physiological and experimental hypoxia on adipose tissue biology and whole‐body metabolism in humans. We conclude that several lines of evidence suggest that alteration of adipose tissue oxygenation may impact metabolic homeostasis, thereby providing a novel strategy to combat chronic metabolic diseases in obese humans.

Low Elevation and Physical Inactivity are Associated with a Higher Prevalence of Metabolic Syndrome in Ecuadorian Adults: A National Cross-Sectional Study

BACKGROUND

Elevation and health-related lifestyles have been associated with the development of metabolic syndrome (MetS). However, such associations have not been investigated extensively in a global context. The present study aimed to determine the associations among elevation of residence, health-related lifestyles, and the risk of MetS in an Ecuadorian adult population.

SUBJECTS AND METHODS

This cross-sectional study was conducted utilizing secondary data from the 2012 Ecuador National Health and Nutrition Survey (ENSANUT-ECU). A total of 6024 adults (1964 men and 4060 women) 20 to 60 years old were included in the study. Elevation was obtained by georeferencing techniques and categorized into low (0-2000 masl) and high (>2001 masl). Dietary intake was measured using a 24-hour recall and health-related lifestyle via risk and physical activity standardized questionnaire. MetS was defined on the basis of the National Cholesterol Education Program Adult Treatment Panel III and the Latin American Diabetes Association criteria. Multiple logistic regression analyses were used to examine whether elevation of residence and health-related lifestyles can increase the risk of MetS.

RESULTS

Residing at low elevation increased prevalence of MetS in men (1.37; 95% CI, 1.05-1.76) and elevated fasting glucose in both men (1.80; 95% CI, 1.32-2.46) and women (1.55; 95% CI, 1.24-1.93) after adjusting for confounders. Additionally, a lack of physical activity was identified as an important factor that raises the risk of increased waist circumference in both men (2.05; 95% CI, 1.22-3.45) and women (1.38; 95% CI, 1.05-1.83) living at low elevation.

CONCLUSION

Our findings suggest that low elevation of residence and physical inactivity are associated with a higher prevalence of MetS in Ecuadorian adults.

Inverse Association Between Metabolic Syndrome and Altitude: A Cross-Sectional Study in an Adult Population of Ecuador

Background: Metabolic syndrome (MetS) is characterized by the clustering of hyperglycemia, hypertension, hypertriglyceridemia, low high-density lipoprotein cholesterol levels and central adiposity. Altitude has been proposed as a protective factor to prevent the development of MetS and its components. Aim: To determine whether living at geographical elevation is associated with MetS and its individual components after adjustment for potential confounders in an Ecuadoran population. Methods: The study included 260 Ecuadoran university graduates over 20 years of age, from the coastal or the Andean Altiplano region. The altitude of residence was imputed with the postal code of each participant residence according to the data of the Ecuadoran Geophysical Institute of the National Polytechnic School. MetS was defined according to the harmonizing definition. Logistic regression models were fitted to assess the relationship between altitude level and the prevalence of MetS and its individual components. To test the internal validity, re-sampling techniques were used (1,000 bootstrap samples). Results: Living at high altitude was associated with less hypercholesterolemia (OR = 0.24; p < 0.001), hyperglycemia (OR = 0.25; p < 0.05) and MetS (OR = 0.24; p < 0.05), after adjusting for potential confounders. At high altitude the bootstrapped logistic regression models showed lower prevalence of hypercholesterolemia (OR = 0.30; p < 0.05), hyperglycemia (OR = 0.22; p < 0.001) and MetS (OR = 0.28; p < 0.05). The MetS score (0-5 points) showed a reduction in the number of MetS components at high altitude compared to sea level (B = -0.34; p = 0.002). A statistically significant lower self-reported energy intake was found in high altitude compared to sea level after adjustment for potential confounders (p < 0.001). Conclusion: In the present study concerning a small Ecuadoran population composed of highly educated adults living at the coast and the Andean Altiplano, living at high altitude (2,758-2,787 m) was associated with a lower prevalence of MetS, hypercholesterolemia and hyperglycemia, compared to the participants at sea level (4-6 m). In addition, an inverse association between altitude and self-reported energy intake was found after adjusting for covariates, suggesting a physiological role of appetite at high altitude even in acclimated subjects.

The Effects of High Altitude on Glucose Homeostasis, Metabolic Control, and Other Diabetes-Related Parameters: From Animal Studies to Real Life

Exposure to high altitude activates several complex and adaptive mechanisms aiming to protect human homeostasis from extreme environmental conditions, such as hypoxia and low temperatures. Short-term exposure is followed by transient hyperglycemia, mainly triggered by the activation of the sympathetic system, whereas long-term exposure results in lower plasma glucose concentrations, mediated by improved insulin sensitivity and augmented peripheral glucose disposal. An inverse relationship between altitude, diabetes, and obesity has been well documented. This is the result of genetic and physiological adaptations principally to hypoxia that favorably affect glucose metabolism; however, the contribution of financial, dietary, and other life-style parameters may also be important. According to existing evidence, people with diabetes are capable of undertaking demanding physical challenges even at extreme altitudes. Still, a number of issues should be taken into account, including the increased physical activity leading to changes in insulin demands and resistance, the performance of measurement systems under extreme weather conditions and the potential deterioration of metabolic control during climbing expeditions. The aim of this review is to present available evidence in the field in a comprehensive way, beginning from the physiology of glucose homeostasis adaptation mechanisms to high altitudes and ending to what real life experience has taught us.

Gestational Diabetes Prevalence at Moderate and High Altitude

BACKGROUND

High-altitude (HA) pregnancies have been associated with decreased glucose levels and increased insulin sensitivity versus sea level. Our objective was to determine if the prevalence of gestational diabetes mellitus (GDM) and the impact of demographic characteristics on GDM diagnosis differed at moderate altitude (MA) versus HA.

METHODS

Using a retrospective cohort design, we compared women living at HA (>8250 ft) and MA (4000-7000 ft) during pregnancy. Exclusion criteria were as follows: multiple gestation, preexisting diabetes, unavailable GDM results, or relocation from a different altitude during pregnancy. GDM diagnosis was determined using Carpenter and Coustan criteria. Data were compared by t-test (continuous variables) or chi-squared tests (categorical variables). Univariate, multivariate, and stepwise regression models were used to assess the impact of various factors on GDM prevalence.

RESULTS

There was no difference in GDM prevalence between altitudes in these populations; the relationship between altitude and GDM was nonsignificant in all regression analyses. At MA, maternal age, Hispanic ethnicity, body mass index (BMI), and gestational age (GA) at testing increased GDM incidence in univariate analyses. At HA, maternal age, Hispanic ethnicity, and multiparity increased GDM incidence in univariate analyses.

CONCLUSION

While GDM prevalence did not differ between MA and HA, the impact of maternal demographic characteristics on GDM risk varied by altitude group. Higher BMI and greater GA at testing increased the incidence of GDM at MA, but not at HA. Multiparity had an effect at HA, but not MA. These differences may represent subtle differences in glucose metabolism at HA.

Nocturnal Hypoxia Improves Glucose Disposal, Decreases Mitochondrial Efficiency, and Increases Reactive Oxygen Species in the Muscle and Liver of C57BL/6J Mice Independent of Weight Change

Although acute exposure to hypoxia can disrupt metabolism, longer-term exposure may normalize glucose homeostasis or even improve glucose disposal in the presence of obesity. We examined the effects of two-week exposure to room air (Air), continuous 10% oxygen (C10%), and 12 hr nocturnal periods of 10% oxygen (N10%) on glucose disposal, insulin responsiveness, and mitochondrial function in lean and obese C57BL/6J mice. Both C10% and N10% improved glucose disposal relative to Air in lean and obese mice without evidence of an increase in insulin responsiveness; however, only the metabolic improvements with N10% exposure occurred in the absence of confounding effects of weight loss. In lean mice, N10% exposure caused a decreased respiratory control ratio (RCR) and increased reactive oxygen species (ROS) production in the mitochondria of the muscle and liver compared to Air-exposed mice. In the absence of hypoxia, obese mice exhibited a decreased RCR in the muscle and increased ROS production in the liver compared to lean mice; however, any additional effects of hypoxia in the presence of obesity were minimal. Our data suggest that the development of mitochondrial inefficiency may contribute to metabolic adaptions to hypoxia, independent of weight, and metabolic adaptations to adiposity, independent of hypoxia.

The prevalence of and risk factors for diabetes mellitus and impaired glucose tolerance among Tibetans in China: a cross-sectional study

The prevalence of diabetes mellitus (DM) and impaired glucose tolerance (IGT) has increased worldwide, although their prevalence and determinants among Tibetans are currently unknown. We thus aimed to explore the prevalence of and risk factors for DM and IGT among Tibetans in China. In 2011, 1659 Tibetan adults (aged ≥ 18 years) from Changdu, China, were recruited to this cross-sectional study. They completed a questionnaire and underwent physical examinations and laboratory testing to assess risk factors for DM and IGT. The age-standardized prevalence of DM and IGT among Tibetans was 6.2% and 19.7%, respectively. A higher annual family income, alcohol consumption, and higher fasting plasma glucose (FPG) level were risk factors for DM, with odds ratio (ORs) and 95% confidence intervals (CIs) of 3.48 (1.43-8.48; P = 0.006) for those with family incomes of > 1600 USD/year, 3.06 (1.31-7.17; P = 0.010) for alcohol consumption, and 13.99 (7.76-25.22; P < 0.001) for FPG level. However, altitude was found to be negatively associated with the risk of DM; compared to individuals living at < 3500 meters, the risk of DM decreased by 65% for those living at 3500-3999 meters (P = 0.034) and by 89% for those living at ≥ 4000 meters (P = 0.015). Age, FPG levels, and low-density lipoprotein cholesterol levels were significantly associated with IGT among Tibetans aged ≥ 18 years. These findings suggest that the prevalence of DM in Tibetans may continue to increase in future decades following rapid economic development, and it is crucial to address the management of conventional risk factors for reducing the disease burden of DM among Tibetans.

Risk of Type 2 Diabetes Mellitus Development in the Native Population of Low- and High-Altitude Regions of Kyrgyzstan: Finnish Diabetes Risc Score Questionnaire Results

Moldobaeva, Marina S., Anastasiya V. Vinogradova, and Marina K. Esenamanova. Risk of type 2 diabetes mellitus development in the native population of low- and high-altitude regions of Kyrgyzstan: Finnish Diabetes Risc Score questionnaire results. High Alt Med Biol. 18:428-435, 2017.

OBJECTIVE

The number of patients with diabetes is steadily growing, but likely only half of all cases are ever identified. The Kyrgyz, native inhabitants of Central Asia, live in the mountainous area and have a particular lifestyle and nutrition. However, the risk of type 2 diabetes mellitus (T2DM) in our population is not well defined. Therefore, we aimed at determining the risk of T2DM development in the Kyrgyz population residing in low- and high-altitude (HAlt) regions by using the Finnish Diabetes Risc Score (FINDRISC) questionnaire.

METHODS

We included in the study 3190 randomly selected participants, including 1780 low-altitude (LAlt) residents (Chu region, 500-1200 m) and 1410 HAlt residents (Naryn region, 2000-4500 m), among whom there were 1207 men and 1983 women. Assessment of T2DM development was conducted by using the FINDRISC questionnaire and risk stratification was performed by region of residency, gender, and age.

RESULTS

An irregular intake of vegetables and fruits, increased waist circumference (WC), and increased body mass index (BMI) were identified as leading risk factors of T2DM development in native residents of Chu and Naryn regions of Kyrgyzstan. The 10-year risk stratification of T2DM development revealed the absence of a very high-risk group; high-risk status was more frequently identified among residents of the LAlt Chu district (4.7% of women and 2.1% of men), as compared with the HAlt population (1.9% of women and 1% of men) (p = 0.0018 for women and p = 0.09 for men).

CONCLUSIONS

In the Kyrgyz population, a 10-year high risk of T2DM development is greater among residents of LAlts as compared with HAlts, irrespective of gender. No very high-risk group was detected in residents of low or HAlts. The leading composites of FINDRISC score are increased WC and BMI, possibly due to irregular intake of vegetables and fruits that are dependent on the altitude of residence and age.

Higher prevalence of unrecognized kidney disease at high altitude

BACKGROUND

High altitude renal syndrome has been described in populations with excessive erythrocytosis. We evaluated whether high altitude (HA) dwellers might be at increased risk for kidney disease.

METHODS

We performed a cross-sectional study to investigate differences in prevalence of kidney function and metabolic syndrome in healthy subjects living at HA vs. sea level (SL) without any known history of hypertension, diabetes or chronic kidney disease.

RESULTS

We examined 293 subjects, aged 40 to 60 years: 125 SL (154 m) and 168 HA (3640 m) dwellers. HA dwellers had higher serum creatinine, lower estimated glomerular function rate (eGFR) (69.5 ± 15.2 vs. 102.1 ± 17.8 ml/min/1.73 m², p < 0.0001), more proteinuria and higher hemoglobin concentrations compared to SL subjects. HA subjects had a lower prevalence of metabolic syndrome. Hemoglobin concentrations correlated inversely with eGFR in female (p = 0.001) and male (p = 0.03) HA dwellers. Using logistic regression analysis to compare subjects with eGFR < 90 vs. > 90 ml/min/1.73 m², a lower eGFR was associated with female gender (odds ratio adjusted: 5.65 [95% confidence interval: 2.43-13.13]; p = 0.001), high altitude (14.78 [6.46-33.79]; p = 0.001), hemoglobin (1.68 [1.16-2.43]; p = 0.001) and uric acid (1.93 [1.36-2.72]; p = 0.001).

CONCLUSIONS

Dwellers at high altitude who are considered healthy have worse kidney function, a higher prevalence of proteinuria and a lower prevalence of metabolic syndrome compared to people living at SL.

Enhanced hepatic insulin signaling in the livers of high altitude native rats under basal conditions and in the livers of low altitude native rats under insulin stimulation: a mechanistic study

This study was designed to investigate the role of the liver in lowering fasting blood glucose levels (FBG) in rats native to high (HA) and low altitude (LA) areas. As compared with LA natives, besides the improved insulin and glucose tolerance, HA native rats had lower FBG, at least mediated by inhibition of hepatic gluconeogenesis and activation of glycogen synthesis. An effect that is mediated by the enhancement of hepatic insulin signaling mediated by the decreased phosphorylation of TSC induced inhibition of mTOR function. Such effect was independent of activation of AMPK nor stabilization of HIF1α, but most probably due to oxidative stress induced REDD1 expression. However, under insulin stimulation, and in spite of the less activated mTOR function in HA native rats, LA native rats had higher glycogen content and reduced levels of gluconeogenic enzymes with a more enhanced insulin signaling, mainly due to higher levels of p-IRS1 (tyr612).

The prevalence of obesity and metabolic syndrome in Tibetan immigrants living in high altitude areas in Ladakh, India

OBJECTIVE

To examine the prevalence of obesity and related cardiovascular disease risk factors among Tibetan immigrants living in high altitude areas.

RESEARCH METHODS & PROCEDURES

A total of 149 Tibetan immigrants aged 20 years and over were recruited in 2016 in Ladakh, India. Anthropometric indices and biochemical factors were measured. Using the provided Asia-Pacific criteria from the World Health Organization, overweight and obese status were determined. Metabolic syndrome (MetS) was defined according to the American Heart Association.

RESULTS

In general, men were older, taller, and had a greater amount of fasting glucose, and uric acid when compared to women. The prevalence of overweight, general obesity, and central obesity was 23.4, 42.6, and 42.6% in men and 7.8, 64.7, and 69.6% in women, respectively. The prevalence of MetS was 10.6% in men and 33.3% in women, respectively. In older subjects, the prevalence of obesity and MetS was found to be greater. In both genders, the prevalence of hypertension, central obesity, and MetS was significantly different among these body mass index (BMI) groups. Compared to the non-central obesity group, the central obesity group has higher weight, BMI, body fat, hip circumference, systolic and diastolic BP, and prevalence of hypertension. No relationship was found between the prevalence of diabetes and fasting glucose and BMI groups or central obesity groups in both genders.

CONCLUSIONS

Among this group of Tibetan immigrants living in high altitude areas, women have a higher prevalence of obesity and MetS than men. No relationship was found between diabetes and obesity.

Diabetes in Immigrant Tibetan Muslims in Kashmir, North India

Tibetan Muslims have migrated from Lhasa (3000 m altitude) to Srinagar, India (altitude 1500 m) about 55 years back. We set out to study the prevalence of diabetes and prediabetes among this immigrant population. All consenting adults aged ≥18 years were questioned about a previous history of diabetes or any other medical history. Anthropometric data were recorded. Fasting blood glucose was measured in duplicate by Accu-check glucometer and HbA1C levels were measured. Of the 281 participants, 26 (9.25%) had diabetes whereas 46 (16.4%) had pre-diabetes; 24 reporting doctor-diagnosed diabetes. Participants with diabetes/pre-diabetes were more likely to be obese, smokers and hypertensive. Multiple logistic regression analysis revealed age to be significantly associated with a higher prevalence of diabetes. One in four adults ≥18 years among Tibetan Muslims have diabetes or prediabetes. Migration to lower altitude could have contributed to this high prevalence.

Synergistic Inhibitory Effects of Hypoxia and Iron Deficiency on Hepatic Glucose Response in Mouse Liver

Hypoxia and iron both regulate metabolism through multiple mechanisms, including hypoxia-inducible transcription factors. The hypoxic effects on glucose disposal and glycolysis are well established, but less is known about the effects of hypoxia and iron deficiency on hepatic gluconeogenesis. We therefore assessed their effects on hepatic glucose production in mice. Weanling C57BL/6 male mice were fed an iron-deficient (4 ppm) or iron-adequate (35 ppm) diet for 14 weeks and were continued in normoxia or exposed to hypoxia (8% O2) for the last 4 weeks of that period. Hypoxic mice became hypoglycemic and displayed impaired hepatic glucose production after a pyruvate challenge, an effect accentuated by an iron-deficient diet. Stabilization of hypoxia-inducible factors under hypoxia resulted in most glucose being converted into lactate and not oxidized. Hepatic pyruvate concentrations were lower in hypoxic mice. The decreased hepatic pyruvate levels were not caused by increased utilization but rather were contributed to by decreased metabolism from gluconeogenic amino acids. Pyruvate carboxylase, which catalyzes the first step of gluconeogenesis, was also downregulated by hypoxia with iron deficiency. Hypoxia, and more so hypoxia with iron deficiency, results in hypoglycemia due to decreased levels of hepatic pyruvate and decreased pyruvate utilization for gluconeogenesis. These data highlight the role of iron levels as an important determinant of glucose metabolism in hypoxia.

PlanHab: the combined and separate effects of 16 days of bed rest and normobaric hypoxic confinement on circulating lipids and indices of insulin sensitivity in healthy men

PlanHab is a planetary habitat simulation study. The atmosphere within future space habitats is anticipated to have reduced Po2, but information is scarce as to how physiological systems may respond to combined exposure to moderate hypoxia and reduced gravity. This study investigated, using a randomized-crossover design, how insulin sensitivity, glucose tolerance, and circulating lipids were affected by 16 days of horizontal bed rest in normobaric normoxia [NBR: FiO2 = 0.209; PiO2 = 133.1 (0.3) mmHg], horizontal bed rest in normobaric hypoxia [HBR: FiO2 = 0.141 (0.004); PiO2 = 90.0 (0.4) mmHg], and confinement in normobaric hypoxia combined with daily moderate intensity exercise (HAMB). A mixed-meal tolerance test, with arterialized-venous blood sampling, was performed in 11 healthy, nonobese men (25-45 yr) before (V1) and on the morning ofday 17of each intervention (V2). Postprandial glucose and c-peptide response were increased at V2 of both bed rest interventions (P< 0.05 in each case), with c-peptide:insulin ratio higher at V2 in HAMB and HBR, both in the fed and fasted state (P< 0.005 in each case). Fasting total cholesterol was reduced at V2 in HAMB [-0.47 (0.36) mmol/l;P< 0.005] and HBR [-0.55 (0.41) mmol/l;P< 0.005]. Fasting HDL was lower at V2 in all interventions, with the reduction observed in HBR [-0.30 (0.21) mmol/l] greater than that measured in HAMB [-0.13 (0.14) mmol/l;P< 0.005] and NBR [-0.17 (0.15) mmol/l;P< 0.05]. Hypoxia did not alter the adverse effects of bed rest on insulin sensitivity and glucose tolerance but appeared to increase insulin clearance. The negative effect of bed rest on HDL was compounded in hypoxia, which may have implications for long-term health of those living in future space habitats.

A Molecular and Whole Body Insight of the Mechanisms Surrounding Glucose Disposal and Insulin Resistance with Hypoxic Treatment in Skeletal Muscle

Although the mechanisms are largely unidentified, the chronic or intermittent hypoxic patterns occurring with respiratory diseases, such as chronic pulmonary disease or obstructive sleep apnea (OSA) and obesity, are commonly associated with glucose intolerance. Indeed, hypoxia has been widely implicated in the development of insulin resistance either via the direct action on insulin receptor substrate (IRS) and protein kinase B (PKB/Akt) or indirectly through adipose tissue expansion and systemic inflammation. Yet hypoxia is also known to encourage glucose transport using insulin-dependent mechanisms, largely reliant on the metabolic master switch, 5' AMP-activated protein kinase (AMPK). In addition, hypoxic exposure has been shown to improve glucose control in type 2 diabetics. The literature surrounding hypoxia-induced changes to glycemic control appears to be confusing and conflicting. How is it that the same stress can seemingly cause insulin resistance while increasing glucose uptake? There is little doubt that acute hypoxia increases glucose metabolism in skeletal muscle and does so using the same pathway as muscle contraction. The purpose of this review paper is to provide an insight into the mechanisms underpinning the observed effects and to open up discussions around the conflicting data surrounding hypoxia and glucose control.

Prevalence of diabetes and impaired fasting glucose in Peru: report from PERUDIAB, a national urban population-based longitudinal study

OBJECTIVES

We aimed to estimate the prevalences of diabetes and impaired fasting glucose (IFG) in a national sample in Peru and assess the relationships with selected sociodemographic variables.

METHODS

We estimated prevalence in PERUDIAB study participants, a nationwide, stratified urban and suburban population selected by random cluster sampling. Between 2010 and 2012, questionnaires were completed and blood tests obtained from 1677 adults ≥25 years of age. Known diabetes was defined as participants having been told so by a doctor or nurse and/or receiving insulin or oral antidiabetic agents. Newly diagnosed diabetes was defined as fasting plasma glucose ≥126 mg/dL determined during the study and without a previous diabetes diagnosis. IFG was defined as fasting plasma glucose of 100-125 mg/dL.

RESULTS

The estimated national prevalence of diabetes was 7.0% (95% CI 5.3% to 8.7%) and it was 8.4% (95% CI 5.6% to 11.3%) in metropolitan Lima. No gender differences were detected. Known and newly diagnosed diabetes prevalences were estimated as 4.2% and 2.8%, respectively. A logistic regression response surface model showed a complex trend for an increased prevalence of diabetes in middle-aged individuals and in those with no formal education. Diabetes prevalence was higher in coastal (8.2%) than in highlands (4.5%; p=0.03), and jungle (3.5%; p<0.02) regions. The estimated national prevalence of IFG was 22.4%, higher in males than in females (28.3% vs 19.1%; p<0.001), and higher in coastal (26.4%) than in highlands (17.4%; p=0.03), but not jungle regions (14.9%; p=0.07).

CONCLUSIONS

This study confirms diabetes as an important public health problem, especially for middle-aged individuals and those with no formal education. 40% of the affected individuals were undiagnosed. The elevated prevalence of IFG shows that nearly a quarter of the adult population of Peru has an increased risk of diabetes.

Glucose homeostasis during short-term and prolonged exposure to high altitudes

Most of the literature related to high altitude medicine is devoted to the short-term effects of high-altitude exposure on human physiology. However, long-term effects of living at high altitudes may be more important in relation to human disease because more than 400 million people worldwide reside above 1500 m. Interestingly, individuals living at higher altitudes have a lower fasting glycemia and better glucose tolerance compared with those who live near sea level. There is also emerging evidence of the lower prevalence of both obesity and diabetes at higher altitudes. The mechanisms underlying improved glucose control at higher altitudes remain unclear. In this review, we present the most current evidence about glucose homeostasis in residents living above 1500 m and discuss possible mechanisms that could explain the lower fasting glycemia and lower prevalence of obesity and diabetes in this population. Understanding the mechanisms that regulate and maintain the lower fasting glycemia in individuals who live at higher altitudes could lead to new therapeutics for impaired glucose homeostasis.

Inverse association between diabetes and altitude: a cross-sectional study in the adult population of the United States

OBJECTIVE

To determine whether geographical elevation is inversely associated with diabetes, while adjusting for multiple risk factors.

METHODS

This is a cross-sectional analysis of publicly available online data from the Behavioral Risk Factor Surveillance System, 2009. Final dataset included 285,196 US adult subjects. Odds ratios were obtained from multilevel mixed-effects logistic regression analysis.

RESULTS

Among US adults (≥20 years old), the odds ratio for diabetes was 1.00 between 0 and 499 m of altitude (reference), 0.95 (95% confidence interval, 0.90-1.01) between 500 and 1,499 m, and 0.88 (0.81-0.96) between 1,500 and 3,500 m, adjusting for age, sex, body mass index, ethnicity, self-reported fruit and vegetable consumption, self-reported physical activity, current smoking status, level of education, income, health status, employment status, and county-level information on migration rate, urbanization, and latitude. The inverse association between altitude and diabetes in the US was found among men [0.84 (0.76-0.94)], but not women [1.09 (0.97-1.22)].

CONCLUSIONS

Among US adults, living at high altitude (1,500-3,500 m) is associated with lower odds of having diabetes than living between 0 and 499 m, while adjusting for multiple risk factors. Our findings suggest that geographical elevation may be an important factor linked to diabetes.

Successive exposure to moderate hypoxia does not affect glucose metabolism and substrate oxidation in young healthy men

Introduction

Exposure to hypoxia has been suggested to acutely alter glucose regulation. However, the effects of successive exposure to moderate hypoxia on postprandial glucose regulation and substrate oxidation pattern after multiple meals have not been elucidated.

Purpose

We examined the effects of successive exposure to moderate hypoxia on metabolic responses and substrate oxidation pattern.

Methods

Eight healthy men (21.0 ± 0.6 yrs, 173 ± 2.3 cm, 70.6 ± 5.0 kg, 23.4 ± 1.1 kg/m²) completed two experimental trials on separate days: a rest trial under normoxic conditions (FiO₂ = 20.9%) and a rest trial under hypoxic conditions (FiO₂ = 15.0%). Experimental trials were performed over 7 h in an environmental chamber. Blood and respiratory gas samples were collected over 7 h. Standard meals were provided 1 h (745 kcal) and 4 h (731 kcal) after entering the chamber.

Results

Although each meal significantly increased blood glucose and serum insulin concentrations (P < 0.05), these responses did not differ significantly between the trials. There were no significant differences in areas under the curves for glucose or insulin concentrations over 7 h between the trials. No significant differences were observed in blood lactate, serum cortisol, free fatty acid, or glycerol concentrations over 7 h between the trials. The oxygen consumption ( ) and carbon dioxide production ( ) 3 h after entering the chamber were significantly higher in the hypoxic trial than in the normoxic trial (P < 0.05). However, the differences did not affect respiratory exchange ratio (RER). The average values of , , and RER did not differ between the trials.

Conclusion

Seven hours of moderate hypoxia did not alter postprandial glucose responses or substrate oxidation in young healthy men.

Time-dependent changes in glucose and insulin regulation during intermittent hypoxia and continuous hypoxia

Hypoxia manifests in many forms including the short repetitive intermittent hypoxia (IH) of sleep apnoea and the continuous hypoxia (CH) of altitude, both of which may impact metabolic function. Based on our own previous studies and the available literature, we hypothesized that whereas acute exposure to IH and CH would lead to comparable metabolic dysfunction, with longer-term exposure, metabolism would normalize to a greater extent with CH than IH. Studies were conducted in lean C57BL/6J mice exposed to either IH or CH for 1 day or 4 weeks and compared to either intermittent air (IA) or unhandled (UN) controls, respectively. We utilized the frequently sampled intravenous glucose tolerance test and minimal model analyses to determine insulin-dependent (insulin sensitivity; S (I)) and insulin-independent (glucose effectiveness; S (g)) glucose disposal, as well as the insulin response to glucose (acute insulin response to glucose; AIR(g)). Our data show that 1-day exposure impaired the glucose tolerance and caused reductions in S (g) and AIR(g) in both the IH and CH groups, but only IH caused a significant decrease in S (I) (7.5 ± 2.7 vs. 17.0 ± 5.3 μU ml(-1) min(-1); p < 0.05). After 4-week exposure, there was evidence of metabolic adaptation in both hypoxic groups, however, in the CH group, there was a supranormal increase in S (I) relative to both UN and IH groups. We conclude that in lean mice, the marked metabolic dysfunction that occurs with acute exposure to hypoxia is reversed to a greater extent with chronic CH exposure than chronic IH exposure.

Chronic hypoxia increases insulin-stimulated glucose uptake in mouse soleus muscle

People living at high altitude appear to have lower blood glucose levels and decreased incidence of diabetes. Faster glucose uptake and increased insulin sensitivity are likely explanations for these findings: skeletal muscle is the largest glucose sink in the body, and its adaptation to the hypoxia of altitude may influence glucose uptake and insulin sensitivity. This study tested the hypothesis that chronic normobaric hypoxia increases insulin-stimulated glucose uptake in soleus muscles and decreases plasma glucose levels. Adult male C57BL/6J mice were kept in normoxia [fraction of inspired O₂ = 21% (Control)] or normobaric hypoxia [fraction of inspired O₂ = 10% (Hypoxia)] for 4 wk. Then blood glucose and insulin levels, in vitro muscle glucose uptake, and indexes of insulin signaling were measured. Chronic hypoxia lowered blood glucose and plasma insulin [glucose: 14.3 ± 0.65 mM in Control vs. 9.9 ± 0.83 mM in Hypoxia (P < 0.001); insulin: 1.2 ± 0.2 ng/ml in Control vs. 0.7 ± 0.1 ng/ml in Hypoxia (P < 0.05)] and increased insulin sensitivity determined by homeostatic model assessment 2 [21.5 ± 3.8 in Control vs. 39.3 ± 5.7 in Hypoxia (P < 0.03)]. There was no significant difference in basal glucose uptake in vitro in soleus muscle (1.59 ± 0.24 and 1.71 ± 0.15 μmol·g⁻¹·h⁻¹ in Control and Hypoxia, respectively). However, insulin-stimulated glucose uptake was 30% higher in the soleus after 4 wk of hypoxia than Control (6.24 ± 0.23 vs. 4.87 ± 0.37 μmol·g⁻¹·h⁻¹, P < 0.02). Muscle glycogen content was not significantly different between the two groups. Levels of glucose transporters 4 and 1, phosphoinositide 3-kinase, glycogen synthase kinase 3, protein kinase B/Akt, and AMP-activated protein kinase were not affected by chronic hypoxia. Akt phosphorylation following insulin stimulation in soleus muscle was significantly (25%) higher in Hypoxia than Control (P < 0.05). Neither glycogen synthase kinase 3 nor AMP-activated protein kinase phosphorylation changed after 4 wk of hypoxia. These results demonstrate that the adaptation of skeletal muscles to chronic hypoxia includes increased insulin-stimulated glucose uptake.

Comparative study of atherosclerotic parameters in Mongolian and Japanese patients with hypertension and diabetes mellitus

AIM

Cardiovascular disease is becoming increasingly more problematic in Mongolia. The cardioankle vascular index (CAVI) and circulating C-reactive protein (CRP) are new atherosclerosis-related parameters, but no comparative studies of atherosclerotic parameters including CAVI and CRP are available between Mongolian and Japanese populations, such as disease populations of hypertension (HT) and diabetes mellitus (DM). Our study objective was to examine atherosclerotic profiles in HT and DM patients in both countries.

METHODS

From a hospital-based population, 156 Mongolian outpatients with HT and DM (men: 46%, mean age: 57.1 years) and 156 age- and sex-matched Japanese outpatients with HT and DM (men: 46%, age: 57.7) were recruited. Body mass index (BMI), heart rate (HR), blood pressure (BP), pulse pressure (PP), ankle-brachial index (ABI), ultrasonographic carotid intima-media thickness (IMT), blood total cholesterol (T-Cho), glucose, insulin and homeostasis model assessment of insulin resistance (HOMA-IR) were measured, in addition to CAVI and CRP.

RESULTS

The levels of BMI, HR, BP, PP, insulin and IMT were significantly higher and T-Cho and glucose were significantly lower in the Mongolian patients in comparison to the Japanese patients. Particularly, the levels of CAVI (mean+/-SD) (8.1+/-1.1 vs. 8.8+/-1.2) and CRP(median[interquartile range])(0.05[0.03-0.12]vs. 0.19[0.09-0.42]mg/dL)were significantly higher in Mongolian than Japanese patients. These significant differences remained unchanged, even after taking into account multiple variables, including BP and HOMA-IR. In addition, except for CAVI in the subgroup of DM, generally similar trends regarding atherosclerotic parameters were seen in the subgroup by sex and disease (HT, DM and HT plus DM).

CONCLUSION

These findings suggest that Mongolian patients with HT and DM may be at higher risk for cardiovascular disease than Japanese patients.