Blood pressure and coronary heart disease in NIDDM subjects at diagnosis: prevalence and risks in a Bangladeshi population

Do obesity, hypertension and dyslipidemia pose significant risks for coronary artery disease among Bangladeshi diabetics?

Background and objectives: For decades the global population has been experiencing diabetic epidemic. The risks related to obesity, diabetes mellitus (DM) and coronary artery diseases (CAD) are well known. This study aimed to assess the prevalence of coronary artery disease (CAD) and its related risks in Bangladeshi diabetics. Materials and methods: The study was conducted at Bangladesh Institute of Research and Rehabilitation in Diabetes, Endocrine and Metabolic Disorders (BIRDEM), a largest referral center for diabetes in Bangladesh. Socio-demographic and clinical history including biochemical investigation report were collected from the BIRDEM registry. The eligible criteria of study participants were: age 30 – 60 year, having DM, non-smoker, free from retinopathy, nephropathy and neuropathy. The prevalence of CAD, systolic hypertension (SHTN) and diastolic hypertension (DHTN) in the registered diabetic patients were estimated. Additionally, the study addressed the risk and predictors of CAD among those with DM. Investigations included – anthropometry, blood pressure, blood glucose, serum lipids and electrocardiogram (ECG). CAD was diagnosed on: (a) history of angina plus positive ECG - either on rest or on stress, post-myocardial infarction (MI) with Q-wave MI or non-Q-MI or echocardiographic evidences. Lipids namely triglycerides (TG), total cholesterol (T-Chol), high density lipoproteins (HDL) and low-density lipoproteins (LDL) were estimated by Hitachi-704 auto-analyzer using enzymatic method. Results: A total of 693 (M /W =295/398) participants volunteered. The prevalence of CAD, SHTN, DHTN and mean arterial hypertension (MAH) were 18.6%, 23.2%, 13.6% and 17.7%, respectively. Their mean (±SD) values of age, body mass index (BMI - kg/m2), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR) and mean arterial pressure (MAP) were 47 (8.6) years, 24.6 (3.5), 0.98(0.05), 0.56(0.06) and 101(11.3) mmHg, respectively. The mean (±SD) of FBG (mmol/L), T-Chol, TG and HDL (mg/dl) were 10.2 ± 4.0, 206 ± 44, 218 ± 86 and 47.5 ± 9.3 respectively. The women had significantly higher BMI (p<0.001), WHtR (p<0.001), SBP (<0.001), MAP (p<0.001), T-Chol (p<0.001) and TG (p=0.043) than men. The risk variables were categorized into quartiles and Chi-sq trend determined whether the increasing prevalence of CAD were significant. Higher quartile of age was found consistently significant (p<0.001). Of the obesity indices, only higher quartile of WHtR was significant (p< 0.05). For BP measures, higher MAP quartiles showed the trend significant (p<0.001). Likewise, for lipids, higher quartiles of TG (p<0.001) and lower quartile of HDL (p<0.001) were significant. Finally, logistic regression estimated the risk related to CAD. The highest age-quintile (>55y: 95% CI: 1.09 - 43.7) and highest TG-quintile (281mg/dl: 95% CI: 1.45-59.7) were proved to be significant predictor of CAD and HDL highest quintile (>54mg/dl) was proved to be significant protecting factor for CAD (95% CI: 0.005-0.583). Conclusion: The study observed the importance of MAP, TG, HDL, T-Chol/HDLR (T-Chol -to HDL ratio) and TG/HDLR (triglycerides-to HDL ratio) as risks for CAD among diabetics. Further study with investigations of echocardiogram, ETT, coronary angiogram and coronary calcium scoring would be helpful in confirming these findings related to CAD risks. IMC J Med Sci. 2023; 17(1): 002. DOI: https://doi.org/10.55010/imcjms.17.002 *Correspondence: M Abu Sayeed, Department of Community Medicine, Ibrahim Medical College, 1/A, Ibrahim Sarani, Segunbagicha, Dhaka 1000, Bangladesh. Email: sayeed1950@gmail.com

Hypertension and its related factors among patients with type 2 diabetes mellitus – a multi-hospital study in Bangladesh

Background

Hypertension and type 2 diabetes are associated with each other, and their coexistence is linked to diabetes-related complications such as stroke, coronary artery disease, kidney disease, retinopathy and diabetic foot. This study aimed to determine the prevalence, awareness and control of hypertension and factors associated with hypertension among people with type 2 diabetes mellitus (T2DM) in Bangladesh.

Methods

A cross-sectional and retrospective study was conducted in 2017, and data from 1252 adults with T2DM were collected from six hospitals that specialise in diabetes care. These hospitals provide primary, secondary and tertiary healthcare and cover the rural and urban populations of Bangladesh. Cross-sectional data were collected from patients via face-to-face interviews, and retrospective data were collected from patients’ past medical records (medical passport), locally known as the patients’ guidebook or record book. The associations between hypertension and its related factors were examined using the bootstrapping method with multiple logistic regression to adjust for potential confounders.

Results

The mean age of participants was 55.14 (± 12.51) years. Hypertension was found to be present among 67.2% of participants, and 95.8% were aware that they had it. Of these, 79.5% attained the blood pressure control. The mean duration of diabetes was 10.86 (± 7.73) years. The variables that were found to be related to hypertension include an age of above 60 years, physical inactivity, being overweight or obese, a longer duration of diabetes and chronic kidney disease.

Conclusion

The prevalence of hypertension as well as its awareness and control were very high among people with known type 2 diabetes. As there is a strong relationship between hypertension and diabetes, patients with diabetes should have their blood pressure regularly monitored to prevent major diabetes-related complications.

Hypertension in Bangladesh: a review

Hypertension (HTN) is an increasingly important medical and public health problem. In Bangladesh, approximately 20% of adult and 40-65% of elderly people suffer from HTN. High incidence of metabolic syndrome, and lifestyle-related factors like obesity, high salt intake, and less physical activity may play important role in the pathophysiology of HTN. The association of angiotensin-converting enzyme (ACE) gene polymorphism and low birth weight with blood pressure has been studied inadequately. Studies have found relationship between mass arsenic poisoning and HTN. Hypovitaminosis D presumably plays role in the aetiopathogenesis of HTN in Bangladeshi population. South Asians appear to respond to antihypertensive therapy in a similar manner to the Whites. The latest National Institute for Health and Clinical Excellence guideline advocates a calcium-channel blocker as step 1 antihypertensive treatment to people aged > 55 years and an ACE inhibitor or a low-cost angiotensin-II receptor blocker for the younger people. Calcium-channel blockers and beta-blockers have been found to be the most commonly prescribed antihypertensive drugs in Bangladesh. Non-adherence to the standard guidelines and irrational drug prescribing are likely to be important. On the other hand, non-adherence to antihypertensive treatment is quite high. At the advent of the new millennium, we are really unaware of our real situation. Large-scale, preferably, nation-wide survey and clinical research are needed to explore the different aspects of HTN in Bangladesh.

Type 2 diabetes in rural and urban population: diverse prevalence and associated risk factors in Bangladesh

AIMS

To describe differences in prevalence of Type 2 diabetes mellitus with its associated risk factors between rural and urban populations in Bangladesh. Diagnostic criteria [fasting blood glucose (FBG) and oral glucose tolerance tests (OGTT)] were compared and reviewed for both populations.

METHODS

A total of 1555 subjects from urban and 4757 from rural communities (age > or = 20 years) with similar cultural and ethnic backgrounds were randomly selected in a cross-sectional survey. FBG values were determined from all and 2-h post-glucose capillary blood samples were determined after a 75-g oral glucose load for a selected number (urban 476, rural 1046).

RESULTS

A higher prevalence of diabetes was found in urban (8.1%) compared with rural populations (2.3%). Age, sex and waist-to-hip ratio for men were significant risk factors for both urban and rural subjects following fasting and 2-h post-glucose values adjusted for a number of confounding variables. Poor agreement was observed between FBG and OGTT for both urban (kappa 0.41) and rural (kappa 0.40) areas.

CONCLUSIONS

A higher prevalence of diabetes mellitus (DM) in the urban population was observed compared with rural subjects despite similar body mass indexes (BMI). Differences in obesity, waist/hip ratio or hypertension failed to explain the increasing occurrence of T2DM in the urban population.

Ethnic subgroup differences in hypertension in Pakistan

OBJECTIVE

Cardiovascular risks are globally elevated in South Asians, but this masks important ethnic subgroup differences in risk factors, such as hypertension, which have not been fully explored. We conducted this study to explore the variations in hypertension within ethnic subgroups among South Asians.

DESIGN

Cross-sectional survey [National Health Survey of Pakistan (NHSP) (1990-1994)].

SETTING

Population based.

PARTICIPANTS

A total of 9442 individuals aged 15 years or over.

METHODS

Data on sociodemographic and clinical variables were collected. Distinct ethnic subgroups - Muhajir, Punjabi, Sindhi, Pashtun and Baluchi - were defined by mother tongue.

MAIN OUTCOME MEASURE

Hypertension defined as systolic blood pressure >or= 140 mmHg or diastolic blood pressure >or= 90 mmHg, or currently receiving antihypertensive therapy.

RESULTS

The age-standardized prevalence of hypertension was highest among Baluchis (25.3% in men and 41.4% in women), then Pashtuns (23.7% in men and 28.4% in women), Muhajirs (24.1% in men and 24.6% in women), and lowest among Punjabis (17.3% in men and 16.4% in women) and Sindhis (19.0% in men and 9.9% in women) (P = 0.001). While hypertension was more prevalent in urban (22.7%) versus rural dwellers (18.1%) [odds ratio (OR) 1.34; 95% confidence interval (CI), 1.20, 1.49], this difference was no longer significant after adjusting for body mass and waist circumference (OR 1.03; 95% CI, 0.91, 1.16). However, ethnic differences persisted after adjusting for major sociodemographic, dietary and clinical risk factors (unadjusted OR for Baluchi versus Sindhi, 2.92; 95% CI, 2.20-3.89; adjusted OR, 2.71; 95% CI, 1.97-3.75).

CONCLUSIONS

A threefold difference in prevalence of hypertension exists between people of South Asian descent, which, unlike the urban/rural difference, cannot be accounted for by measured risk factors. Further study would provide valuable etiological and therapeutic clues.

Pressor effects of orexins injected intracisternally and to rostral ventrolateral medulla of anesthetized rats

Orexin A and B, two recently isolated hypothalamic peptides, have been reported to increase food consumption upon intracerebroventricular injections in rats. In addition to the hypothalamus, orexin A-immunoreactive fibers have been observed in several areas of the medulla that are associated with cardiovascular functions. The present study was undertaken to evaluate the hypothesis that orexins may influence cardiovascular response by interacting with neurons in the medulla. Intracisternal injections of orexins A (0.0056-7.0 nmol) or B (0.028-0.28 nmol) dose dependently increased mean arterial pressure (MAP) by 4-27 mmHg and heart rate (HR) by 26-80 beats/min in urethan-anesthetized rats, with orexin A being more effective in this regard. MAP and HR were not changed by intravenous injection of orexins at higher concentrations. Microinjection of orexin A (14 pmol/50.6 nl) to the rostral ventrolateral medulla, which was confirmed by histological examination, increased MAP and HR. Our results indicate that, in addition to a role in positive feeding behavior, orexins may enhance cardiovascular response via an action on medullary neurons.